MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Annalen der Physik' source. Mon, 06 Feb 2012 20:24:43 +0100 http://www.medworm.com/index.php?rid=5664543&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100269 AbstractThe Heisenberg exchange parameters for the Heusler compound Co2NiGa with L21 structure were calculated using the Korringa–Kohn–Rostoker method and by employing the magnetic‐force theorem to obtain the total energy changes associated with the local rotation of magnetization direction. The crystal structure was subjected to pressure and the corresponding dependence of the magnetic exchange couplings were determined. Curie temperatures obtained by applying mean field theory (MFT) reveals a slightly nonlinear decrease with pressure and it is related to the changes of the magnetic moment and the electronic density of states. Further investigation of the pressure dependence of the Curie temperature and magnetization suggests that this particular compound is a weak itinerant ferroma... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664543 Mon, 06 Feb 2012 05:00:00 +0100 5664543 http://www.medworm.com/index.php?rid=5664542&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100271 AbstractA new mechanism is proposed for the magnetization reversal of molecular nanomagnets such as Fe8. In this process the spin tunnels from the lowest state near one easy direction to the first excited state near the opposite easy direction, and subsequently decays to the second easy direction with the emission of a phonon, or it first emits a phonon and then tunnels to the final state. This mechanism is the simplest imaginable one that allows magnetization relaxation in the presence of a longitudinal magnetic field that is so large that the nuclear spin environment cannot absorb the energy required for energy conservation to hold. It is proposed as a way of understanding both magnetization realaxation and Landau‐Zener‐Stückelberg (LZS) experiments. The requisite Fermi golden rule ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664542 Mon, 06 Feb 2012 05:00:00 +0100 5664542 http://www.medworm.com/index.php?rid=5657048&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100328 AbstractA three‐level system with partially broken SU(3) symmetry immersed in a metal, comprised of a unique non‐interacting ground state and two‐fold degenerate excited states, exhibits a stable two‐channel Kondo fixed point within a wide range of parameters, as has been shown in previous work. Such systems can, for instance, be realized by protons dissolved in a metal and bound in the interstitial space of the host lattice, where the degeneracy of excited rotational states is guaranteed by the space inversion symmetry of the lattice. We analyze the robustness of the 2CK fixed point with respect to a level splitting of the excited states and discuss how this may explain the behavior of the well‐known dI/dV spectra measured by Ralph and Buhrman on ultrasmall quantum point contact... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5657048 Thu, 02 Feb 2012 05:00:00 +0100 5657048 http://www.medworm.com/index.php?rid=5657047&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100287 AbstractA model system for the injection of fermionic particles from filled source sites into an empty chain is investigated. The ensuing dynamics for Hermitian as well as for non‐Hermitian time evolution, where the particles cannot return to the bath sites (quantum ratchet), is studied. A non‐homogeneous hybridization between bath and chain sites permits transient currents in the chain. Non‐interacting particles show decoherence in the thermodynamic limit: the average particle number and the average current density in the chain become stationary for long times, whereas the single‐particle density matrix displays large fluctuations around its mean value. Using the numerical time‐dependent density‐matrix renormalization group (t‐DMRG) method it is demonstrated, on the other ha... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5657047 Thu, 02 Feb 2012 05:00:00 +0100 5657047 http://www.medworm.com/index.php?rid=5657046&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100274 AbstractWe develop an inhomogeneous mean‐field theory for the extended Bose‐Hubbard model with a quadratic, confining potential. In the absence of this potential, our mean‐field theory yields the phase diagram of the homogeneous extended Bose‐Hubbard model. This phase diagram shows a superfluid (SF) phase and lobes of Mott‐insulator (MI), density‐wave (DW), and supersolid (SS) phases in the plane of the chemical potential µ and on‐site repulsion U; we present phase diagrams for representative values of V, the repulsive energy for bosons on nearest‐neighbor sites. We demonstrate that, when the confining potential is present, superfluid and density‐wave order parameters are nonuniform; in particular, we obtain, for a few representative values of parameters, spherical shell... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5657046 Thu, 02 Feb 2012 05:00:00 +0100 5657046 http://www.medworm.com/index.php?rid=5657045&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100258 We present results for the temperature dependence of the weak localization correction to the conductance for the experimentally relevant parameter range and discuss the possibility to observe the elusive 0D‐regime of dephasing in different mesoscopic systems. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5657045 Thu, 02 Feb 2012 05:00:00 +0100 5657045 http://www.medworm.com/index.php?rid=5664552&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100710 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664552 Wed, 01 Feb 2012 05:00:00 +0100 5664552 http://www.medworm.com/index.php?rid=5664551&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100708 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664551 Wed, 01 Feb 2012 05:00:00 +0100 5664551 http://www.medworm.com/index.php?rid=5664550&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100712 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664550 Wed, 01 Feb 2012 05:00:00 +0100 5664550 http://www.medworm.com/index.php?rid=5664549&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201290002 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664549 Wed, 01 Feb 2012 05:00:00 +0100 5664549 http://www.medworm.com/index.php?rid=5664548&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100709 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664548 Wed, 01 Feb 2012 05:00:00 +0100 5664548 http://www.medworm.com/index.php?rid=5664547&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201200702 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664547 Wed, 01 Feb 2012 05:00:00 +0100 5664547 http://www.medworm.com/index.php?rid=5664546&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201290001 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664546 Wed, 01 Feb 2012 05:00:00 +0100 5664546 http://www.medworm.com/index.php?rid=5664545&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201252402 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664545 Wed, 01 Feb 2012 05:00:00 +0100 5664545 http://www.medworm.com/index.php?rid=5664544&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201290000 The center graph shows the tunable double‐control quantum interference as the detuning frequencies vary. As the two‐photon resonance occurs (i.e., δp‐ δc = 0 or δp‐ δc' = 0), the “double‐control interference” parameter Δ drastically changes. Picture: J. Qi Shen, p. 85 in this issue. Background graph taken from C. Emary, C. Pöltl, T. Brandes, Phys. Rev. B 80, 235321 (2009) http://prb.aps.org/abstract/PRB/v80/i23/e235321, © 2009 by The American Physical Society). Readers may view, browse, and / or download material for temporary copying purposes only, provided these uses are for noncommercial personal purposes. Except as provided by law, th is material may not be further reproduced, distributed, transmitted, modified, adapted, performed, displayed, published, or sold in ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664544 Wed, 01 Feb 2012 05:00:00 +0100 5664544 http://www.medworm.com/index.php?rid=5664541&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100275 AbstractIn recent years, an increasing number of systems displaying exotic quantum states like unconventional superconductivity, quantum spin‐liquids, or topological states were experimentally found. Here we summarize findings in quantum Monte Carlo simulations of correlated electrons on a honeycomb lattice, the structure of graphene, that revealed an unexpected spin‐liquid emerging between a state described by massless Dirac fermions and an antiferromagnetically ordered Mott insulator. Moreover, we found that this quantum‐disordered state is a resonating valence‐bond (RVB) liquid, akin to the one proposed for high temperature superconductors. This was the first unbiased determination of a RVB‐liquid in an electronic system. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5664541 Wed, 01 Feb 2012 05:00:00 +0100 5664541 http://www.medworm.com/index.php?rid=5635834&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100197 AbstractRadial slave boson representations have the particular advantage that the expectation values of their respective fields are finite even without the formal introduction of spurious Bose condensates for each of the bosonic fields. The expectation values of the radial (real) fields are in fact to be interpreted as the density of empty or singly occupied sites. Whereas the radial representation of the Barnes slave bosons has been investigated before, a setup for the functional integral of radial bosonic fields in the more physical Kotliar‐Ruckenstein representation has not been accomplished to date. We implement a path integral procedure with suitable renormalization factors for a strongly correlated two‐site model which allows to control the formal steps in the intricate evaluatio... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5635834 Thu, 26 Jan 2012 05:00:00 +0100 5635834 http://www.medworm.com/index.php?rid=5635833&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100244 AbstractBirkhoff's theorem is discussed in the frame of f(R) gravity by using its scalar–tensor representation. Modified gravity has become very popular in recent times as it is able to reproduce the unification of inflation and late‐time acceleration with no need of a dark energy component or an inflation field. Here, another aspect of modified f(R) gravity is studied, specifically the range of validity of Birkhoff's theorem, compared with another alternative to general relativity, the well‐known Brans–Dicke theory. As a novelty, here both theories are studied using a conformal transformation and writing the actions in the Einstein frame, where spherically symmetric solutions are studied using perturbation techniques. The differences between both theories are analyzed as well as t... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5635833 Thu, 26 Jan 2012 05:00:00 +0100 5635833 http://www.medworm.com/index.php?rid=5657044&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100298 AbstractIn this brief communication, the charge susceptibility, χc,imp, is calculated for the single impurity Anderson model in the Kondo regime with the density matrix renormalization group theory (DMRG). Excellent agreement with the Bethe‐Ansatz (BA) results is found in the appropriate limit where the (effective) level broadening Γ☆ and the charging energy, U, are much smaller than the conduction electron bandwidth, D. Deviations occur for large interactions U>D, where we find that χc,imp decays faster, approximately by a factor D/U, as compared to the BA‐prediction. Our work is of methodological relevance, e.g., for studies of the Kondo‐effect in molecular systems, in the sense that it prepares treatments of (spinful) few‐orbital models in the Kondo regime. (Source: Anna... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5657044 Mon, 02 Jan 2012 05:00:00 +0100 5657044 http://www.medworm.com/index.php?rid=5635832&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100246 AbstractIn recent years germanium has been emerging as a mainstream material that could have important applications in the microelectronics industry. The principle aim of this study is to review investigations of the diffusion of technologically important p‐ and n‐type dopants as well as surface and interface passivation issues in germanium. The diffusion of impurities in germanium is interrelated to the formation of clusters whenever possible, and possibilities for point defect engineering are discussed in view of recent results. The importance of electrically active defects on the Ge surface and interfaces is addressed considering strategies to suppress them and to passivate the surfaces/interfaces, bearing in mind their importance for advanced devices. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5635832 Mon, 02 Jan 2012 05:00:00 +0100 5635832 http://www.medworm.com/index.php?rid=5604403&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100260 AbstractThe linear electromagnetic response of a uniform three‐dimensional electron gas to a longitudinal electric field is determined by the known Lindhard dielectric function ϵqω. Using a similar approach, we derive exact analytical expressions for the second‐order nonlinear electromagnetic response of the electron gas. We calculate the second‐order polarizability α(2)qω of the system and, within the self‐consistent‐field approach, the second‐order response function, analogous to ϵqω. The best conditions for the observation of the second‐harmonic generation are analyzed. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5604403 Mon, 02 Jan 2012 05:00:00 +0100 5604403 http://www.medworm.com/index.php?rid=5593761&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000168 AbstractThe paper is devoted to an explanation of the accelerated rate of expansion of the Universe. Usually the acceleration of the Universe, which is described by FRW metric, is due to dark energy. It is shown that this effect may be considered as a manifestation of torsion tensor for a flat Universe in the realm of Teleparallel gravity. An observer with radial field velocity obey Hubble's Law. As a consequence it is established that this is radial acceleration in a flat Universe. In Eq. (35) the acceleration is written in terms of the deceleration parameter, the Hubble’s constant and the proper distance. This may be interpreted as an acceleration of the Universe. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5593761 Mon, 02 Jan 2012 05:00:00 +0100 5593761 http://www.medworm.com/index.php?rid=5577052&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100305 AbstractBarbour's response to our recent paper on “Mach's principle and higher‐dimensional dynamics” describes an approach to Mach's principle in which the universe as a whole is involved in the definition of inertial frames of reference. Moreover, Barbour's theoretical procedure is in agreement with general relativity for a finite universe that is spatially closed. However, we prefer an operational approach that relies ultimately on observational data. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5577052 Mon, 02 Jan 2012 05:00:00 +0100 5577052 http://www.medworm.com/index.php?rid=5534075&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100279 AbstractIn Josephson junction arrays, vortices form stable topological excitations. A key step towards the understanding of their properties was the observation made by Eckern and Schmid that in low‐capacitance junction arrays a vortex behaves as a massive particle moving in a periodic potential and subject to dissipation. The mass is low and quantum effects become observable. The present contribution provides a review of these properties together with a discussion of similar scenarios realized in optical lattices. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5534075 Fri, 23 Dec 2011 14:18:41 +0100 5534075 http://www.medworm.com/index.php?rid=5534077&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100277 AbstractMethods of charge projectors using special gauge transformations for tagging particles are presented. Such engineering of a many‐body wave function allows extracting information regarding properties of a physical system beyond average values. The method is first used to establish under which circumstances the properties of particle currents can be understood as discrete transfers of particles from one region to another. Next, the method is extended to show that in a tunnel junction coupled to a two‐level system, the transmission of electrical noise causes decoherence and thereby a projective measurement of the two‐level system as encoded by the amount of tunnelled charge. Finally the method is extended to deal with the exceptional circumstance where a measurement on a system ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5534077 Fri, 23 Dec 2011 05:00:00 +0100 5534077 http://www.medworm.com/index.php?rid=5534076&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100253 AbstractSpin‐orbit interaction is usefully classified as extrinsic or intrinsic, depending on its origin: the potential due to random impurities (extrinsic), or the crystalline potential associated with the band or device structure (intrinsic). In this paper we will show how, by using a SU(2) formulation, the two sources may be described in an elegant and unified way. As a result we obtain a simple description of the interplay of the two types of spin‐orbit interaction, and a physically transparent explanation of the vanishing of the d.c. spin Hall conductivity in a Rashba two‐dimensional electron gas when spin relaxation is neglected, as well as its reinstatement when spin relaxation is allowed. Furthermore, we obtain an explicit formula for the transverse spin polarization created ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5534076 Fri, 23 Dec 2011 05:00:00 +0100 5534076 http://www.medworm.com/index.php?rid=5520830&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100707 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520830 Tue, 20 Dec 2011 13:21:20 +0100 5520830 http://www.medworm.com/index.php?rid=5520829&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100706 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520829 Tue, 20 Dec 2011 13:21:19 +0100 5520829 http://www.medworm.com/index.php?rid=5520828&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100705 AbstractOn his way to general relativity, Einstein used the equivalence principle to formulate a theory of the static gravitational field. In this context he introduced an approximate coordinate transformation to an accelerated frame which turns out to be closely related to Rindler coordinates, widely used in modern general relativity. This work, published in the Annalen, led him directly to interpret gravitation in terms of spacetime curvature. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520828 Tue, 20 Dec 2011 13:21:18 +0100 5520828 http://www.medworm.com/index.php?rid=5520827&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190015 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520827 Tue, 20 Dec 2011 13:21:17 +0100 5520827 http://www.medworm.com/index.php?rid=5520826&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100704 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520826 Tue, 20 Dec 2011 13:21:16 +0100 5520826 http://www.medworm.com/index.php?rid=5520825&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100702 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520825 Tue, 20 Dec 2011 13:21:15 +0100 5520825 http://www.medworm.com/index.php?rid=5520824&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100701 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520824 Tue, 20 Dec 2011 13:21:14 +0100 5520824 http://www.medworm.com/index.php?rid=5520823&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190014 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520823 Tue, 20 Dec 2011 13:21:13 +0100 5520823 http://www.medworm.com/index.php?rid=5520822&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201252401 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520822 Tue, 20 Dec 2011 13:21:11 +0100 5520822 http://www.medworm.com/index.php?rid=5520821&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190013 Color contour plot of the momentum resolved total spectral function of the iron pnictide compound BaFe2As2 near the X and Γ points, respectively, of the Brillouin zone. The results were obtained within the LDA+DMFT approach, a computational scheme for the realistic modelling of correlated electron materials based on the combination of density functional theory in the local density approximation (LDA) with dynamical mean‐field theory (DMFT). Picture: After S. L. Skornyakov, A. V. Efremov, N. A. Skorikov, M. A. Korotin, Yu. A. Izyumov, V. I. Anisimov, A. V. Kozhevnikov, and D. Vollhardt; Phys. Rev. B 80, 092501 (2009) (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520821 Tue, 20 Dec 2011 13:21:10 +0100 5520821 http://www.medworm.com/index.php?rid=5520820&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100183 AbstractMultilevel quantum coherence and its quantum‐vacuum counterpart, where a three‐level dark state is involved, are suggested in order to achieve new photonic and quantum optical applications. It is shown that such a three‐level dark state in a four‐level tripod‐configuration atomic system consists of three lower levels, where constructive and destructive quantum interference between two control transitions (driven by two control fields) arises. We point out that the controllable optical response due to the double‐control tunable quantum interference can be utilized to design some fascinating new photonic devices such as logic gates, photonic transistors and switches at quantum level. A single‐photon two‐input XOR logic gate (in which the incident “gate” photons ar... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5520820 Tue, 20 Dec 2011 13:21:03 +0100 5520820 http://www.medworm.com/index.php?rid=5473899&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190011 A closer look into the grand history of Annalen der Physik: themes which ccupied the minds of physicists one century ago (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5473899 Mon, 05 Dec 2011 14:37:42 +0100 5473899 http://www.medworm.com/index.php?rid=5473898&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100141 AbstractThis paper describes equilibrium ensembles of thermally excited electromagnetic fields in layered media. The obtained results complement Planck's law of thermal radiation that determines the spectrum of the radiation but supplies little information about the ensemble of eigenfields (normal modes) excited in the medium. The developments regarding these ensembles presented in this paper make it possible to apply perturbation techniques for the analysis of the ensembles of radiated fields in layered media with a steady heat flux.This paper describes equilibrium ensembles of thermally excited electromagnetic fields in layered media. The obtained results complement Planck's law of thermal radiation that determines the spectrum of the radiation but supplies little information about the e... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5473898 Mon, 05 Dec 2011 14:37:40 +0100 5473898 http://www.medworm.com/index.php?rid=5473897&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152323 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5473897 Mon, 05 Dec 2011 14:37:34 +0100 5473897 http://www.medworm.com/index.php?rid=5473896&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152312 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5473896 Mon, 05 Dec 2011 14:37:33 +0100 5473896 http://www.medworm.com/index.php?rid=5473895&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152334 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5473895 Mon, 05 Dec 2011 14:37:31 +0100 5473895 http://www.medworm.com/index.php?rid=5473894&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190012 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5473894 Mon, 05 Dec 2011 14:37:30 +0100 5473894 http://www.medworm.com/index.php?rid=5418327&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100166 AbstractIn a general spacetime, the possible choices for the field of orthonormal tetrads lead (in standard conditions) to equivalent Dirac equations. However, the Hamiltonian operator is got from rewriting the Dirac equation in a form adapted to a particular reference frame, or class of coordinate systems. That rewriting does not commute with changing the tetrad field (uα ). The data of a reference frame F fixes a four‐velocity field v, and also fixes a rotation‐rate field Ω. It is natural to impose that u0 = v. We show that then the spatial triad (up) can only be rotating w.r.t. F, and that the title problem is solved if one imposes that the corresponding rotation rate Ξ be equal to Ω – or also, if one imposes that Ξ = 0. We also analyze other proposals which were aimed at sol... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5418327 Tue, 15 Nov 2011 05:00:00 +0100 5418327 http://www.medworm.com/index.php?rid=5397328&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100226 AbstractIt is proposed that the mathematical models for any physical systems that are based in first principles, such as conservation laws or balance principles, have some common elements, namely, a space of kinematical states, a space of dynamical states, a constitutive law that associates dynamical states with kinematical states, as well as a duality principle. The equations of motion or statics then come about from, on the one hand, specifying the integrability of the kinematical state, and on the other hand, specifying a statement that is dual to it for the dynamical states. Examples are given from various fundamental physical systems. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5397328 Tue, 08 Nov 2011 05:00:00 +0100 5397328 http://www.medworm.com/index.php?rid=5437613&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100235 AbstractIn their recent “Mach's principle and higher‐dimensional dynamics”, Mashhoon and Wesson argue that Mach's principle is not properly incorporated into general relativity and that in Einstein's theory “the origin of inertia remains essentially the same as in Newtonian physics”. While it is true that the motion of a single test particle in a Newtonian inertial frame of reference appears essentially the same as in an Einsteinian local inertial frame, this misses the point. The issue is not what motion looks like in an inertial frame of reference but what is the origin of the inertial frame. Unlike Newtonian dynamics, general relativity does implement Mach's principle when considered from this correctly formulated point of view. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5437613 Fri, 04 Nov 2011 04:00:00 +0100 5437613 http://www.medworm.com/index.php?rid=5428567&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100156 AbstractA magnon‐phonon interaction model is set up in a two‐dimensional ferromagnetic compound square‐lattice system. Using the Matsubara Green function theory we calculated the magnon dispersion curves on the main symmetric line in Brillouin zone, compared the influences of the magnetic ion optical phonon with non‐magnetic ion optical phonon on the magnetic excitation of the system and discussed the influences of various parameters on the magnon softening. The lower Debye temperature of ferromagnetic materials is, the more likely the magnon softening occurs. It turned out that the optical phonon‐magnon coupling plays an important role on the magnon softening, the longitudinal optical phonon contributes the most to the magnon softening and magnon damping. It is also found that t... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5428567 Fri, 04 Nov 2011 04:00:00 +0100 5428567 http://www.medworm.com/index.php?rid=5418326&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100228 AbstractWe review the work and life of Otto Stern who developed the molecular beam technique and with its aid laid the foundations of experimental atomic physics. Among the key results of his research are: the experimental test of the Maxwell‐Boltzmann distribution of molecular velocities (1920), experimental demonstration of space quantization of angular momentum (1922), diffraction of matter waves comprised of atoms and molecules by crystals (1931) and the determination of the magnetic dipole moments of the proton and deuteron (1933). (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5418326 Fri, 04 Nov 2011 04:00:00 +0100 5418326 http://www.medworm.com/index.php?rid=5397327&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100133 AbstractFerromagnet/Superconductor/Ferromagnet (F/S/F) trilayers, in which the establishing of a Fulde‐Ferrell Larkin‐Ovchinnikov (FFLO) like state leads to interference effects of the superconducting pairing wave function, form the core of the superconducting spin valve. The realization of strong critical temperature oscillations in such trilayers, as a function of the ferromagnetic layer thicknesses or, even more efficient, reentrant superconductivity, are the key condition to obtain a large spin valve effect, i.e. a large shift in the critical temperature. Both phenomena have been realized experimentally in the Cu41Ni59/Nb/Cu41Ni59 trilayers investigated in the present work. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5397327 Fri, 04 Nov 2011 04:00:00 +0100 5397327 http://www.medworm.com/index.php?rid=5376256&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100194 AbstractRecently, the Elementary Process Theory has been introduced as an axiomatic system with a potential application as a foundational framework for physics. This addendum clarifies the primitive concepts ‘phase quantum’ and ‘monad’ that play a central role in the physical picture that arises from the axiomatic system. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5376256 Fri, 04 Nov 2011 04:00:00 +0100 5376256 http://www.medworm.com/index.php?rid=5376257&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100250 AbstractElectronic correlations strongly influence the properties of matter. For example, they can induce a discontinuous transition from conducting to insulating behavior. In this paper basic terms of the physics of correlated electrons are explained. In particular, I describe some of the steps that led to the formulation of a comprehensive, non‐perturbative many‐body approach to correlated quantum many‐body systems, the dynamical mean‐field theory (DMFT). The DMFT becomes exact in the limit of high lattice dimensions (d → ∞) and allows one to go beyond the investigation of simple correlation models and thereby better understand, and even predict, the properties of electronically correlated materials. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5376257 Thu, 03 Nov 2011 04:00:00 +0100 5376257 http://www.medworm.com/index.php?rid=5355857&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100165 AbstractThrough the motivation of the recent discovery of dispersionless regions in the band structure of the delafossites, a model density of states of free fermions including a d anomaly is studied. The resulting temperature dependence of the chemical potential is obtained both exactly and by different approximation schemes which are then discussed thoroughly. This includes the introduction of an approximation of the polylogarithm difference which is capable of accessing a parameter range neither covered by Sommerfeld expansion nor by Boltzmann approximation. It is found that the Fermi temperature and several other temperature scales may be very low, giving rise to experimentally observable behaviours differing from the one described by Fermi liquid theory. In particular, two kinds of ap... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5355857 Fri, 28 Oct 2011 06:35:14 +0100 5355857 http://www.medworm.com/index.php?rid=5311335&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100180 The set of InN nanocolumn samples discussed in the article was not grown using Au as a catalyst. Instead, the growth was performed catalyst‐free by plasma‐assisted molecular beam epitaxy. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5311335 Thu, 13 Oct 2011 15:15:23 +0100 5311335 http://www.medworm.com/index.php?rid=5311334&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100096 AbstractWe study neutron bound states in a particular (1+1)‐supersymmetric configuration. A simple physical setup is chosen so that the effective interaction becomes a particular kind of double Dirac delta potential. In this configuration it is shown that the neutron distinguishes between positive and negative electric charge as a consequence of a purely quantum mechanical effect. The theoretical background is presented and a possible application to a real‐life physical system is discussed.The authors study neutron bound states in a particular (1+1)‐supersymmetric configuration. A simple physical setup is chosen so that the effective interaction becomes a particular kind of double Dirac delta potential. In this configuration it is shown that the neutron distinguishes between positive... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5311334 Thu, 13 Oct 2011 15:15:18 +0100 5311334 http://www.medworm.com/index.php?rid=5311333&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100078 AbstractIt has been suggested that consciousness plays an important role in quantum mechanics as it is necessary for the collapse of wave function during the measurement. Here we formulated several predictions that follow from this hypothetical relationship and that can be empirically tested. Experimental results that are already available suggest falsification of these predictions. Thus, the suggested link between human consciousness and collapse of wave function does not seem viable. We discuss the implications of these conclusions on the role of the human observer for quantum mechanics and on the role of quantum mechanics for the observer's consciousness. It has been suggested that consciousness plays an important role in quantum mechanics as it is necessary for the collapse of wave fun... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5311333 Thu, 13 Oct 2011 15:15:16 +0100 5311333 http://www.medworm.com/index.php?rid=5311332&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152333 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5311332 Thu, 13 Oct 2011 15:15:05 +0100 5311332 http://www.medworm.com/index.php?rid=5311331&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152322 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5311331 Thu, 13 Oct 2011 15:15:03 +0100 5311331 http://www.medworm.com/index.php?rid=5311330&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190010 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5311330 Thu, 13 Oct 2011 15:15:01 +0100 5311330 http://www.medworm.com/index.php?rid=5246776&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100179 AbstractAn analysis of ground‐based observations of solar irradiance was recently published in this journal, reporting an apparent increase of solar irradiance on the ground of the order of 1 % between solar minima and maxima [1]. Since the corresponding variations in total solar irradiance on top of the atmosphere are accurately determined from satellite observations to be of the order of 0.1 % only [2], the one order of magnitude stronger effect in the terrestrial insolation data was interpreted as evidence for cosmic‐ray induced aerosol formation in the atmosphere. In my opinion, however, this result does not reflect reality. Using the energy budget of Earth's surface, I show that changes of ground‐based insolation with the solar cycle of the order of 1 % between solar minima and ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5246776 Fri, 23 Sep 2011 14:23:56 +0100 5246776 http://www.medworm.com/index.php?rid=5234001&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201110470 KCuF3 is the paradigmatic compound for the co‐operative Jahn‐Teller effect. But do we really know its structure? (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5234001 Tue, 20 Sep 2011 04:25:54 +0100 5234001 http://www.medworm.com/index.php?rid=5234000&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152310 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5234000 Tue, 20 Sep 2011 04:25:45 +0100 5234000 http://www.medworm.com/index.php?rid=5233999&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152399 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5233999 Tue, 20 Sep 2011 04:25:44 +0100 5233999 http://www.medworm.com/index.php?rid=5233998&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190009 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5233998 Tue, 20 Sep 2011 04:25:43 +0100 5233998 http://www.medworm.com/index.php?rid=5246781&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100087 AbstractWe study the influence of a classical background based on the violation of the Lorentz symmetry on the relativistic Anandan quantum phase. We show that the choice of the Lorentz symmetry violation background provides an abelian contribution for the relativistic Anandan quantum phase. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5246781 Tue, 20 Sep 2011 04:00:00 +0100 5246781 http://www.medworm.com/index.php?rid=5246780&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100171 AbstractIn my reply I present a re‐analysis of the data of the Smithsonian Astrophysical Observatory (SAO). For this, a new data reduction method is introduced, allowing a drastic lowering of data scatter, so that the time series of the reduced data clearly shows the ≈︁ 1 % variation of the terrestric solar irradiance in parallel with solar activity. The implications are discussed. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5246780 Tue, 20 Sep 2011 04:00:00 +0100 5246780 http://www.medworm.com/index.php?rid=5246779&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100163 We present the next‐to‐next‐to‐leading order post‐Newtonian (PN) spin(1)‐spin(2) Hamiltonian for two self‐gravitating spinning compact objects. If both objects are rapidly rotating, then the corresponding interaction is comparable in strength to a 4PN effect. The Hamiltonian is checked via the global Poincaré algebra with the center‐of‐mass vector uniquely determined by an ansatz. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5246779 Tue, 20 Sep 2011 04:00:00 +0100 5246779 http://www.medworm.com/index.php?rid=5246778&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000158 AbstractIn this work we study the effects of the geometry and topology of a cylinder on the energy levels of an electron moving in a homogeneous magnetic field. We consider the existence of topological defects as a screw dislocation and a disclination. When we take the region of movement as the full cylindrical surface, we find that, by increasing the strength of the screw dislocation, the dispersion on the electronic energy levels is affected and monotonically increasing. For an electron moving in an almost flat region we show that the dispersion on the Landau levels decrease monotonically as we increase the strength of the screw dislocation. The lowest Landau level can reach a zero value, leaving the energy of the system solely given by the geometry of the cylinder, which does not depend... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5246778 Tue, 20 Sep 2011 04:00:00 +0100 5246778 http://www.medworm.com/index.php?rid=5246777&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100136 AbstractWe show the existence of an anticentrifugal force for a quantum particle in a bent waveguide. This effect may be observed in interference experiments which are sensitive to the additional phase of the wavefunction gained in the bent regions and can find application in distinguishing between straight and bent geometries. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5246777 Tue, 20 Sep 2011 04:00:00 +0100 5246777 http://www.medworm.com/index.php?rid=5218044&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100017 AbstractIn the Fractional Quantum Hall Effect (FQHE), in the noninteracting limit, only a fraction ν of the Lowest Landau Level (LLL) is occupied, producing a huge degeneracy. Interactions lift this degeneracy and mix in higher LL's. In the limit in which we ignore all but the LLL (i.e., let the inverse electron mass 1/m → ∞), the kinetic energy is an irrelevant constant and the ratio of potential to kinetic energy is essentially infinite, making this the most strongly correlated problem imaginable. I give a telegraphic review of the Hamiltonian Theory of the FQHE developed with Ganpathy Murthy that deals with this problem with some success. A nodding acquaintance with FQHE physics is presumed. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218044 Fri, 26 Aug 2011 04:00:00 +0100 5218044 http://www.medworm.com/index.php?rid=5218043&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100022 AbstractA technique based on positive semidefinite operator properties has been used in deducing exact ground states for hexagon chains of polyphenylene type (hexagons interconnected by bonds build up the 1D periodic structure), placed in a constant external magnetic field B perpendicular to the surface containing the system. The used Hubbard type of model takes into account B by Peierls phase factors, and has the peculiar property to provide only flat bands in the bare band structure for elevated external field values independent on the parameters entering in the kinetic part of the Hamiltonian. The deduced ground states are non‐magnetic or ferromagnetic in character, localized in the thermodynamic limit, and besides the fact that B is able to switch the system between different phases,... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218043 Fri, 26 Aug 2011 04:00:00 +0100 5218043 http://www.medworm.com/index.php?rid=5218042&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100023 AbstractThe simple Gutzwiller approximation, applied to the approach to Mott localization in a half‐filled band Hubbard model, gives a remarkably good description of the properties of liquid 3He as the liquid‐solid transition is approached under pressure. The key variable, the density of unbound doubly occupied and empty sites is evaluated keeping only single site correlations. We extend the Gutzwiller approximation to incorporate nearest neighbor correlations. This extension improves the agreement with the experimental evolution of the spin susceptibility and effective mass with pressure, but does not remove the large discrepancy in the compressibility.The simple Gutzwiller approximation, applied to the approach to Mott localization in a half‐filled band Hubbard model, gives a remar... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218042 Fri, 26 Aug 2011 04:00:00 +0100 5218042 http://www.medworm.com/index.php?rid=5218041&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100044 AbstractVariational wave functions are very useful for describing the panoply of ground states found in interacting many‐electron systems. Some particular trial states are “adiabatically” linked to a reference state, from which they borrow the essential properties. A prominent example is the Gutzwiller ansatz, where one starts with the filled Fermi sea. A simple soluble example, the anisotropic XY chain, illustrates the adiabatic continuity of this class of wave functions. To describe symmetry breaking, one has to modify the reference state accordingly. Alternatively, a quantum phase transition can be described by a pair of variational wave functions, starting at weak and strong coupling, respectively. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218041 Fri, 26 Aug 2011 04:00:00 +0100 5218041 http://www.medworm.com/index.php?rid=5218040&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100025 AbstractWe study effects of quantum coherence due to scatterings of electrons on impurities on two‐particle vertex functions. We use the diagrammatic perturbation expansion in the impurity potential and analyze possible ways how to introduce renormalizations on the two‐particle level. We discuss the differences between the low‐dimensional self‐consistent theory of Vollhardt and Wölfle and the high‐dimensional one of Janiš and Kolorenč. Finally we demonstrate, using the latter approach, the emergence of the localized phase in the Falicov‐Kimball model. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218040 Fri, 26 Aug 2011 04:00:00 +0100 5218040 http://www.medworm.com/index.php?rid=5218039&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100043 AbstractIn this article we formulate the superperturbation theory for the Anderson impurity model on the real axis. The resulting impurity solver allows to evaluate dynamical quantities without numerical analytical continuation by the maximum entropy method or Padé approximants. This makes the solver well suited to study multiplet effects in solids within the dynamical mean field theory. First examples including multi‐orbital problems are discussed.In this article the authors formulate the superperturbation theory for the Anderson impurity model on the real axis. The resulting impurity solver allows to evaluate dynamical quantities without numerical analytical continuation by the maximum entropy method or Padé approximants. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218039 Fri, 26 Aug 2011 04:00:00 +0100 5218039 http://www.medworm.com/index.php?rid=5218038&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100036 AbstractWe propose an approach for the ab initio calculation of materials with strong electronic correlations which is based on all local (fully irreducible) vertex corrections beyond the bare Coulomb interaction. It includes the so‐called GW and dynamical mean field theory and important non‐local correlations beyond, with a computational effort estimated to be still manageable.The authors propose an approach for the ab initio calculation of materials with strong electronic correlations which is based on all local (fully irreducible) vertex corrections beyond the bare Coulomb interaction. It includes the so‐called GW and dynamical mean field theory and important non‐local correlations beyond, with a computational effort estimated to be still manageable. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218038 Fri, 26 Aug 2011 04:00:00 +0100 5218038 http://www.medworm.com/index.php?rid=5218037&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100021 AbstractThe anisotropic two‐orbital Hubbard model with different bandwidths and degrees of frustration in each orbital is investigated in the framework of both single‐site dynamical mean‐field theory (DMFT) as well as its cluster extension (DCA) for clusters up to four sites combined with a continuous‐time quantum Monte Carlo algorithm. This model shows a rich phase diagram which includes the appearance of orbital selective phase transitions, non‐Fermi liquid behavior as well as antiferromagnetic metallic states. We discuss the advantages and drawbacks of employing the single‐site DMFT with respect to DCA and the consequences for the physical picture obtained out of these calculations. Finally, we argue that such a minimal model may be of relevance to understand the nature of t... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218037 Fri, 26 Aug 2011 04:00:00 +0100 5218037 http://www.medworm.com/index.php?rid=5218036&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100027 AbstractWe review our investigations of electronic properties of strongly correlated materials using the combination of first principles electronic band structures and the dynamical mean‐field theory, so called LDA+DMFT method. Our investigations focus on two phenomena, the spin state transitions and their relationship to the metal‐insulator transition, and the effect of hybridization between correlated and ligand orbitals in charge‐transfer type materials. The pressure driven spin transitions are studied for a group of materials containing MnO, FeO and Fe2O3. To investigate the hybridization effects we focus on NiO and NiS(Se)2. We identify various mechanisms of the metal‐insulator transition, which can take place in multi‐band systems, in addition to the band‐width control kn... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218036 Fri, 26 Aug 2011 04:00:00 +0100 5218036 http://www.medworm.com/index.php?rid=5218035&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100042 AbstractWhen spatial correlations are short‐range, the physics of strongly correlated systems is controlled by local quantum fluctuations. In those regimes, Dynamical Mean‐Field Theory can be viewed as a `compass' which provides guidance on the relevant degrees of freedom and their effective dynamics over intermediate energy scales. These intermediate energy scales and associated crossovers play a crucial role in the physics of strongly correlated materials. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218035 Fri, 26 Aug 2011 04:00:00 +0100 5218035 http://www.medworm.com/index.php?rid=5218034&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100031 AbstractRecent developments on studies of transport through quantum dots obtained by applying the time‐dependent density matrix renormalization group method are summarized. Some new aspects of Kondo physics which appear in nonequilibrium steady states are discussed both for the single dot case and for the serially coupled double‐quantum‐dot case. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218034 Fri, 26 Aug 2011 04:00:00 +0100 5218034 http://www.medworm.com/index.php?rid=5218033&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100040 AbstractInterrelations between global and local structure and magnetism and transport in three‐dimensional perovskite manganites is reviewed and compared with recent studies on thin films and superlattices. The concept of correlated Jahn‐Teller (JT) polarons is discussed within the phase separation scenario; their role in the local and global structural modifications of manganites is demonstrated. Polaron correlations, affected by external control parameters (temperature, electric and magnetic fields, doping, light, strain) may be very efficient to modify the ground state of manganites. Examples of electronic control of the structure by means of interface modifications, electric field and mechanical strain are highlighted.Interrelations between global and local structure and magnetism ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218033 Fri, 26 Aug 2011 04:00:00 +0100 5218033 http://www.medworm.com/index.php?rid=5218032&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100026 We report on polarization dependent reflectivity measurements in KCuF3 in the far‐infrared frequency regime. The observed IR active phonons at room temperature are in agreement with the expected modes for tetragonal symmetry. We observe a splitting of one mode already at 150 K and the appearance of a new mode in the vicinity of the Néel temperature.The authors report on polarization dependent reflectivity measurements in KCuF3 in the far‐infrared frequency regime. The observed IR active phonons at room temperature are in agreement with the expected modes for tetragonal symmetry. A splitting of one mode already at 150 K and the appearance of a new mode in the vicinity of the Néel temperature is observed. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218032 Fri, 26 Aug 2011 04:00:00 +0100 5218032 http://www.medworm.com/index.php?rid=5218031&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100035 AbstractUsing general arguments of an optimization taking place between the pair wave function and the repulsive part of the electron‐electron interaction, we analyze the superconducting gap in materials with multiple Fermi‐surface (FS) pockets, with exemplary application to two proto‐type ferropnictide setups. The main point of our work is to show that the SC state, its gap, and, in particular, its anisotropy in momentum space is determined by an optimization which determines and optimizes the interplay between the attractive interaction in the SC‐channel and the Coulomb repulsion. This optimization problem is unavoidable in a multi‐band SC situation: for the pnictides, it appears because of a frustration in the s±‐channel, when more than two FS‐pockets are involved in sett... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218031 Fri, 26 Aug 2011 04:00:00 +0100 5218031 http://www.medworm.com/index.php?rid=5218030&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100028 AbstractUnderdoped Mott insulators provide us with a challenge of many‐body physics. Recent renewed understanding is discussed in terms of the evolution of pole and zero structure of the single‐particle Green's function. Pseudogap as well as Fermi arc/pocket structure in the underdoped cuprates is well reproduced from the recent cluster extension of the dynamical mean‐field theory. Emergent coexisting zeros and poles set the underdoped Mott insulator apart from the Fermi liquid, separated by topological transitions. The cofermion proposed as a generalization of exciton in the slave‐boson framework accounts for the origin of the zero surface formation. The cofermion‐quasiparticle hybridization gap offers a natural understanding of the pseudogap and various unusual Mottness. Furthe... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218030 Fri, 26 Aug 2011 04:00:00 +0100 5218030 http://www.medworm.com/index.php?rid=5218029&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100039 AbstractWe analyze the scaling behavior at and near a quantum critical point separating a semimetallic from a superfluid phase. To this end we compute the renormalization group flow for a model of attractively interacting electrons with a linear dispersion around a single Dirac point. We study both ground state and finite temperature properties. In two dimensions, the electrons and the order parameter fluctuations exhibit power‐law scaling with anomalous scaling dimensions. The quasi‐particle weight and the Fermi velocity vanish at the quantum critical point. The order parameter correlation length turns out to be infinite everywhere in the semimetallic ground state. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218029 Fri, 26 Aug 2011 04:00:00 +0100 5218029 http://www.medworm.com/index.php?rid=5218028&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100033 AbstractFeSb2 has been recently identified as a new model system for studying many‐body renormalizations in a d‐electron based narrow gap semiconducting system, strongly resembling FeSi. The electron‐electron correlations in FeSb2 manifest themselves in a wide variety of physical properties including electrical and thermal transport, optical conductivity, magnetic susceptibility, specific heat and so on. We review some of the properties that form a set of experimental evidences revealing a significant role of correlation effects in FeSb2. The metallic state derived from slight Te doping in FeSb2, which exhibits a large quasiparticle mass, will also be introduced. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218028 Fri, 26 Aug 2011 04:00:00 +0100 5218028 http://www.medworm.com/index.php?rid=5218027&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100034 AbstractThe metal‐insulator (MI) transition in Si:P can be tuned by varying the P concentration or – for barely insulating samples – by application of uniaxial stress S. On‐site Coulomb interactions lead to the formation of localized magnetic moments and the Kondo effect on the metallic side, and to a Hubbard splitting of the donor band on the insulating side. Continuous stress tuning allows the observation of finite‐temperature dynamic scaling of σ (T,S) and hence a reliable determination of the critical exponent μ of the extrapolated zero‐temperature conductivity σ (0) ∼ | S ‐ Sc |μ, i.e., μ = 1, and of the dynamical exponent z = 3. The issue of half‐filling vs. away from half‐filling of the donor band (i.e., uncompensated vs. compensated semiconductors) is discu... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218027 Fri, 26 Aug 2011 04:00:00 +0100 5218027 http://www.medworm.com/index.php?rid=5218026&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100015 AbstractLandau quasiparticle (qp) theory may be extended into the non‐Fermi liquid regime of metallic compounds near a quantum critical point (QCP), provided the width of the quasiparticle states is less than their energy. Sufficiently far from the QCP, when the critical fluctuations are non‐interacting, their influence on the qp properties may be calculated in a controlled way. A prominent example is the `marginal Fermi liquid,' characterized by a logarithmic variation of the specific heat coefficient and a linear variation of the resistivity with temperature. The latter is induced by the interaction of qps with three‐dimensional ferromagnetic (FM) or, in a disordered system, with quasi‐two‐dimensional antiferromagnetic (AFM) spin fluctuations. It is argued that both types of fl... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218026 Fri, 26 Aug 2011 04:00:00 +0100 5218026 http://www.medworm.com/index.php?rid=5218025&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201010471 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218025 Fri, 26 Aug 2011 04:00:00 +0100 5218025 http://www.medworm.com/index.php?rid=5218024&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152308 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218024 Fri, 26 Aug 2011 04:00:00 +0100 5218024 http://www.medworm.com/index.php?rid=5218023&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152398 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218023 Fri, 26 Aug 2011 04:00:00 +0100 5218023 http://www.medworm.com/index.php?rid=5218022&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190008 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218022 Fri, 26 Aug 2011 04:00:00 +0100 5218022 http://www.medworm.com/index.php?rid=5218021&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100062 AbstractThis paper is intended to show that a review in the concept of the game theoretical utility, the revised utility to be applied to the definition of the utility of a wave function representing an object subsystem relative to its observer subsystem, both within an isolated system, leads to the emergence of Max Born's rule as a profit under a von Neumann good measure game. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5218021 Fri, 26 Aug 2011 04:00:00 +0100 5218021 http://www.medworm.com/index.php?rid=5094526&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100101 AbstractWe are investigating the dynamics of a new Poincaré gauge theory of gravity model, which has cross coupling between the spin‐0+ and spin‐0‐ modes. To this end we are considering a very appropriate situation – homogeneous‐isotropic cosmologies – which is relatively simple, and yet all the modes have non‐trivial dynamics which reveals physically interesting and possibly observable results. More specifically we consider manifestly isotropic Bianchi class A cosmologies. Here the first order equations obtained from an effective Lagrangian are linearized and the normal modes are found. These turn out to control the asymptotic late time cosmological normal modes. Numerical evolution confirms the late time asymptotic approximation and shows the expected effects of the cross ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5094526 Wed, 03 Aug 2011 23:00:00 +0100 5094526 http://www.medworm.com/index.php?rid=5094525&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100067 AbstractWe show that in the trapped ion‐laser interaction all the regimes may be considered analytically. We may solve not only for different laser intensities, but also away from resonance and from the Lamb‐Dicke regime. It is found a dispersive Hamiltonian for the high intensity regime, that, being diagonal, its evolution operator may be easily calculated. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5094525 Wed, 03 Aug 2011 23:00:00 +0100 5094525 http://www.medworm.com/index.php?rid=5048680&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100007 AbstractThe article provides full‐analytic gravitational wave (GW) forms for eccentric nonspinning compact binaries of arbitrary mass ratio in the time Fourier domain. The semi‐analytical property of recent descriptions, i.e. the demand of inverting the higher‐order Kepler equation numerically but keeping all other computations analytic, is avoided for the first time. The article is a completion of a previous one (M. Tessmer and G. Schäfer, Phys. Rev. D 82, 124064 (2010)) to second post‐Newtonian (2PN) order in the harmonic GW amplitude and conservative orbital dynamics. A fully analytical inversion formula of the Kepler equation in harmonic coordinates is provided, as well as the analytic time Fourier expansion of trigonometric functions of the eccentric anomaly in terms of sines... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5048680 Sun, 17 Jul 2011 23:00:00 +0100 5048680 http://www.medworm.com/index.php?rid=5156287&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201110472 AbstractIn a generalized Schrödinger picture, we consider the motion of a relativistic particle in an external field (like in the case of a harmonic oscillator). In this picture the analogs of the Schrödinger operators of the particle are independent of both the time and the space coordinates. These operators induce operators which are related to Killing vectors of the Anti de Sitter (AdS) space. We also consider the nonrelativistic limit. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5156287 Wed, 06 Jul 2011 23:00:00 +0100 5156287 http://www.medworm.com/index.php?rid=5117640&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100006 AbstractWe study f(R)‐gravity with torsion in presence of the most general ELKO matter, checking the consistency of the conservation laws with the matter field equations; we discuss some mathematical features of the field equations in connection with a cosmological application. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5117640 Wed, 06 Jul 2011 23:00:00 +0100 5117640 http://www.medworm.com/index.php?rid=5094524&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100119 AbstractThere are solutions of Maxwell equations in vacuum in which the magnetic and the electric lines have a nontrivial topology. This behaviour has physical consequences since it is related to classical expressions indicating aspects of the photon content of the electromagnetic field. In this work we present for the first time an exact solution of Maxwell equations in vacuum, having non trivial topology, in which there is an exchange of helicity between the electric and magnetic part of such field. We calculate the temporal evolution of the magnetic and electric helicities, and explain the exchange of helicity making use of the Chern‐Simon form. We also have found and explained that, as time goes to infinity, both helicities reach the same value and the exchange between the magnetic a... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5094524 Wed, 06 Jul 2011 23:00:00 +0100 5094524 http://www.medworm.com/index.php?rid=5048679&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100100 AbstractWe briefly discuss the current status of Mach's principle in general relativity and point out that its last vestige, namely, the gravitomagnetic field associated with rotation, has recently been measured for the earth in the GP‐B experiment. Furthermore, in his analysis of the foundations of Newtonian mechanics, Mach provided an operational definition for inertial mass and pointed out that time and space are conceptually distinct from their operational definitions by means of masses. Mach recognized that this circumstance is due to the lack of any a priori connection between the inertial mass of a body and its Newtonian state in space and time. One possible way to improve upon this situation in classical physics is to associate mass with an extra dimension. Indeed, Einstein's the... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5048679 Wed, 06 Jul 2011 23:00:00 +0100 5048679 http://www.medworm.com/index.php?rid=5006941&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100094 We present the next‐to‐next‐to‐leading order post‐Newtonian (PN) spin‐orbit Hamiltonian for two self‐gravitating spinning compact objects. If at least one of the objects is rapidly rotating, then the corresponding interaction is comparable in strength to a 3.5PN effect. The result in the present paper in fact completes the knowledge of the post‐Newtonian Hamiltonian for binary spinning black holes up to and including 3.5PN. The Hamiltonian is checked via known results for the test‐spin case and via the global Poincaré algebra with the center‐of‐mass vector uniquely determined by an ansatz. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=5006941 Wed, 06 Jul 2011 23:00:00 +0100 5006941 http://www.medworm.com/index.php?rid=4983802&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100013 AbstractA recent assertion that inertial and gravitational forces are entropic forces is discussed. A more conventional approach is stressed herein, whereby entropy is treated as a result of relative motion between observers in different frames of reference. It is demonstrated that the entropy associated with inertial and gravitational forces is dependent upon the well known lapse function of general relativity. An interpretation of the temperature and entropy of an accelerating body is then developed, and used to relate the entropic force to Newton's second law of motion. The entropic force is also derived in general coordinates. An expression of the gravitational entropy of in‐falling matter is then derived by way of Schwarzschild coordinates. As a final consideration, the entropy of a... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4983802 Thu, 30 Jun 2011 14:15:02 +0100 4983802 http://www.medworm.com/index.php?rid=4983804&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100135 AbstractPlanck's law of thermal radiation is limited to equilibrium systems that have a definite temperature and do not carry any heat flux. Here we extend it to steady‐state systems with a constant heat flux. The obtained formulas explicitly describe the spectrum of thermal radiation in every direction and provide a sound basis for the self‐consistent analysis of radiative heat transport across interfaces, gaps, layered and other important structures. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4983804 Tue, 28 Jun 2011 23:00:00 +0100 4983804 http://www.medworm.com/index.php?rid=4983803&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100045 We present a generalization of the recently developed dual‐fermion approach introduced for correlated lattices to non‐equilibrium problems. In its local limit, the approach has been used to devise an efficient impurity solver, the superperturbation solver for the Anderson impurity model (AIM). Here we show that the general dual perturbation theory can be formulated on the Keldysh contour. Starting from a reference Hamiltonian system, in which the time‐dependent solution is found by exact diagonalization, we make a dual perturbation expansion in order to account for the relaxation effects from the fermionic bath. Simple test results for closed as well as open quantum systems in a fermionic bath are presented. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4983803 Tue, 28 Jun 2011 23:00:00 +0100 4983803 http://www.medworm.com/index.php?rid=4974882&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201110469 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4974882 Tue, 28 Jun 2011 19:50:47 +0100 4974882 http://www.medworm.com/index.php?rid=4974881&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100060 AbstractThe Dirac equation in a curved spacetime depends on a field of coefficients (essentially the Dirac matrices), for which a continuum of different choices are possible. We study the conditions under which a change of the coefficient fields leads to an equivalent Hamiltonian operator H, or to an equivalent energy operator E. We do that for the standard version of the gravitational Dirac equation, and for two alternative equations based on the tensor representation of the Dirac fields. The latter equations may be defined when the spacetime is four‐dimensional, noncompact, and admits a spinor structure. We find that, for each among the three versions of the equation, the vast majority of the possible coefficient changes do not lead to an equivalent operator H, nor to an equivalent ope... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4974881 Tue, 28 Jun 2011 19:50:45 +0100 4974881 http://www.medworm.com/index.php?rid=4974880&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152307 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4974880 Tue, 28 Jun 2011 19:50:44 +0100 4974880 http://www.medworm.com/index.php?rid=4974879&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152397 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4974879 Tue, 28 Jun 2011 19:50:44 +0100 4974879 http://www.medworm.com/index.php?rid=4974878&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190007 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4974878 Tue, 28 Jun 2011 19:50:43 +0100 4974878 http://www.medworm.com/index.php?rid=4951663&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100018 AbstractWe show that the relativistic analogue of the Landau‐He‐McKellar‐Wilkens quantization can be achieved through the noninertial effects of the Fermi‐Walker reference frame without assuming the existence of a magnetic charge density and discuss the nonrelativistic limit of the energy levels. We also obtain the Dirac spinors for positive‐energy values parallel and antiparallel to the z axis of the spacetime and obtain the Gordon decomposition of the Dirac probability current Jμ (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4951663 Mon, 20 Jun 2011 23:00:00 +0100 4951663 http://www.medworm.com/index.php?rid=4932726&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100080 AbstractWe study the deterministic dynamics of non‐interacting classical gas particles confined to a one‐dimensional box as a pedagogical toy model for the relaxation of the Boltzmann distribution towards equilibrium. Hard container walls alone induce a uniform distribution of the gas particles at large times. For the relaxation of the velocity distribution we model the dynamical walls by independent scatterers. The Markov property guarantees a stationary but not necessarily thermal velocity distribution for the gas particles at large times. We identify the conditions for physical walls where the stationary velocity distribution is the Maxwell distribution. For our numerical simulation we represent the wall particles by independent harmonic oscillators. The corresponding dynamical map ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4932726 Tue, 14 Jun 2011 23:00:00 +0100 4932726 http://www.medworm.com/index.php?rid=4951662&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000144 AbstractIn this article, we present proper quantization rule, ∫k(x) dx ‐ ∫k0(x) dx = nπ, where and study solvable potentials. We find that the energy spectra of solvable systems can be calculated only from its ground state obtained by the Sturm‐Liouville theorem. The previous complicated and tedious integral calculations involved in exact quantization rule are greatly simplified. The beauty and simplicity of proper quantization rule come from its meaning – whenever the number of the nodes of the logarithmic derivative ϕ(x) = ψ(x)‐1dψ(x) /dx or the number of the nodes of the wave function ψ(x) increases by one, the momentum integral will increase by π. We apply two different quantization rules to carry out a few typically solvable quantum systems such as the one‐dimensio... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4951662 Wed, 08 Jun 2011 23:00:00 +0100 4951662 http://www.medworm.com/index.php?rid=4932725&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000165 AbstractWe investigate the D‐dimensional Klein‐Gordon equation in the presence of both Coulomb and Cornell potentials by quasi‐exact methodology. The Coulomb potential yields a degenerate result as the dimension increases, i.e. the quantum number l plays no role in the energy relation. For the Cornell potential, however, the behavior is different and no degeneracy exists. Closed form of eigenfunctions is reported and the energy behavior for different states is numerically discussed. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4932725 Wed, 08 Jun 2011 23:00:00 +0100 4932725 http://www.medworm.com/index.php?rid=4882828&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190006 A closer look into the grand history of Annalen der Physik: themes which ccupied the minds of physicists one century ago (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882828 Wed, 01 Jun 2011 00:05:01 +0100 4882828 http://www.medworm.com/index.php?rid=4882827&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000148 AbstractA long‐standing, though ill‐understood problem in rocket dynamics, rocket response to random, altitude‐dependent nozzle side‐loads, is investigated. Side loads arise during low altitude flight due to random, asymmetric, shock‐induced separation of in‐nozzle boundary layers. In this paper, stochastic evolution of the in‐nozzle boundary layer separation line, an essential feature underlying side load generation, is connected to random, altitude‐dependent rotational and translational rocket response via a set of simple analytical models. Separation line motion, extant on a fast boundary layer time scale, is modeled as an Ornstein‐Uhlenbeck process. Pitch and yaw responses, taking place on a long, rocket dynamics time scale, are shown to likewise evolve as OU processe... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882827 Wed, 01 Jun 2011 00:04:59 +0100 4882827 http://www.medworm.com/index.php?rid=4882826&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100081 AbstractThermal modeling of complex systems faces the problems of an effective digitalization of the detailed geometry and properties of the system, calculation of the thermal flows and temperature maps, treatment of the thermal radiation including possible multiple reflections, inclusion of additional external influences, extraction of the radiation pressure from calculated surface data as well as computational effectiveness. In previous publications [1, 2] the solution to these problems have been outlined and a first application to the Pioneer spacecraft have been shown. Here we like to present the application of our thermal modeling to the Rosetta flyby anomaly as well as to the Pioneer anomaly. The analysis outlines that thermal recoil pressure is not the cause of the Rosetta flyby ano... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882826 Wed, 01 Jun 2011 00:04:57 +0100 4882826 http://www.medworm.com/index.php?rid=4882825&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152316 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882825 Wed, 01 Jun 2011 00:04:57 +0100 4882825 http://www.medworm.com/index.php?rid=4882824&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152306 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882824 Wed, 01 Jun 2011 00:04:56 +0100 4882824 http://www.medworm.com/index.php?rid=4882823&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152396 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882823 Wed, 01 Jun 2011 00:04:54 +0100 4882823 http://www.medworm.com/index.php?rid=4882822&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190005 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882822 Wed, 01 Jun 2011 00:04:54 +0100 4882822 http://www.medworm.com/index.php?rid=4882821&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100032 AbstractA Weyl geometric scale covariant approach to gravity due to Omote, Dirac, and Utiyama (1971ff) is reconsidered. It can be extended to the electroweak sector of elementary particle fields, taking into account their basic scaling freedom. Already Cheng (1988) indicated that electroweak symmetry breaking, usually attributed to the Higgs field with a boson expected at 0.1–0.3 TeV, may be due to a coupling between Weyl geometric gravity and electroweak interactions. Weyl geometry seems to be well suited for treating questions of elementary particle physics, which relate to scale invariance and its “breaking”. This setting suggests the existence of a scalar field boson at the surprisingly low energy of ∼ 1 eV. That may appear unlikely; but, as a payoff, the acquirement of mass ar... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4882821 Wed, 01 Jun 2011 00:04:52 +0100 4882821 http://www.medworm.com/index.php?rid=4812285&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100030 AbstractWe calculate energy and momentum of a spherically symmetric dilaton frame using the gravitational energy‐momentum 3‐form within the tetrad formulation of general relativity (GR). The frame we use is characterized by an arbitrary function ϒ with the help of which all the previously found solutions can be reproduced. We show how the effect of inertia (which is mainly reproduced from ϒ) makes the total energy and momentum always different from the well known result when we use the Riemannian connection . On the other hand, when use is made of the covariant formulation of teleparallel gravity, which implies to take into account the pure gauge connection, teleparallel gravity always yields the physically relevant result for the energy and momentum. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4812285 Sun, 08 May 2011 23:00:00 +0100 4812285 http://www.medworm.com/index.php?rid=4732952&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100038 AbstractThe evolution of a flat, isotropic and homogeneous universe is studied. The background geometry in the early phases of the universe is conjectured to be filled with causal bulk viscous fluid and dark energy. The energy density relations obtained from the assumption of covariant conservation of energy‐momentum tensor of the background matter in the early universe are used to derive the basic equation for the Hubble parameter H. The viscous properties described by ultra‐relativistic equations of state and bulk viscosity taken from recent heavy‐ion collisions and lattice QCD calculations have been utilized to give an approximate solution of the field equations. The cosmological constant is conjectured to be related to the energy density of the vacuum. In this treatment, there is... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4732952 Thu, 21 Apr 2011 14:30:43 +0100 4732952 http://www.medworm.com/index.php?rid=4732951&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152305 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4732951 Thu, 21 Apr 2011 14:30:37 +0100 4732951 http://www.medworm.com/index.php?rid=4732950&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152395 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4732950 Thu, 21 Apr 2011 14:30:37 +0100 4732950 http://www.medworm.com/index.php?rid=4732949&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190004 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4732949 Thu, 21 Apr 2011 14:30:36 +0100 4732949 http://www.medworm.com/index.php?rid=4732948&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201110467 AbstractOn the basis of his ‘Zürich Notebook’ I shall describe a particularly fruitful phase in Einstein's struggle on the way to general relativity. These research notes are an extremely illuminating source for understanding Einstein's main physical arguments and conceptual difficulties that delayed his discovery of general relativity by about three years. Together with the ‘Entwurf’ theory in collaboration with Marcel Grossmann, these notes also show that the final theory was missed late in 1912 within a hair's breadth. The Einstein‐Grossmann theory, published almost exactly hundred years ago, contains, however, virtually all essential elements of Einstein's definite gravitation theory. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4732948 Thu, 21 Apr 2011 14:30:34 +0100 4732948 http://www.medworm.com/index.php?rid=4703875&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000161 We present a new mechanism of spin reversal in nanodots. That is, the microwave field directly induces the reversal of the coherent‐state spins instead of indirectly through the magnetic vortex. We obtain the space distribution of coherent‐state spins in terms of a quantum theory, and calculate the time of spin reversal. This spin‐reversal process may be used to serve as a storage mechanism of binary information. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4703875 Thu, 31 Mar 2011 23:00:00 +0100 4703875 http://www.medworm.com/index.php?rid=4676120&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152315 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4676120 Thu, 31 Mar 2011 23:00:00 +0100 4676120 http://www.medworm.com/index.php?rid=4590774&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000147 AbstractWe study the interaction of many fields. We obtain an effective Hamiltonian for this system by using a method recently introduced that produces a small rotation to the Hamiltonian that allows to neglect some terms in the rotated Hamiltonian. We show that coherent states remain coherent under the action of a quadratic Hamiltonian and by solving the eigenvalue and eigenvector problem for tridiagonal matrices we also show that a system of n interacting harmonic oscillators, initially in coherent states, remain coherent during the interaction. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4590774 Tue, 15 Mar 2011 22:33:13 +0100 4590774 http://www.medworm.com/index.php?rid=4559605&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152304 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4559605 Tue, 08 Mar 2011 21:03:44 +0100 4559605 http://www.medworm.com/index.php?rid=4559604&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152314 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4559604 Tue, 08 Mar 2011 21:03:43 +0100 4559604 http://www.medworm.com/index.php?rid=4559603&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190003 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4559603 Tue, 08 Mar 2011 21:03:43 +0100 4559603 http://www.medworm.com/index.php?rid=4559602&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000135 We present here an extension of relativistic dynamics for which all admissible solutions will have have a speed bounded by the speed of light c and the acceleration bounded by am. An additional Doppler type shift for an accelerated source is predicted. The formulas for such shift are the same as for the usual Doppler shift with v/c replaced by a/am. The W. Kündig experiment of measurement of the transverse Doppler shift in an accelerated system was also exposed to a longtitudal shift due to the acceleration. This experiment, as reanalyzed by Kholmetskii et al., shows that the Clock Hypothesis is not valid. Based on the results of this experiment, we predict that the value of the maximal acceleration am is of the order 1019m/s2. Moreover, our analysis provides a way to measure experimental... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4559602 Tue, 08 Mar 2011 21:03:41 +0100 4559602 http://www.medworm.com/index.php?rid=4488978&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000178 AbstractThe present article aims at an extension of the canonical formalism of Arnowitt, Deser, and Misner from self‐gravitating point‐masses to objects with spin. This would allow interesting applications, e.g., within the post‐Newtonian (PN) approximation. The extension succeeded via an action approach to linear order in the single spins of the objects without restriction to any further approximation. An order‐by‐order construction within the PN approximation is possible and performed to the formal 3.5PN order as a verification. In principle both approaches are applicable to higher orders in spin. The PN next‐to‐leading order spin(1)‐spin(1) level was tackled, modeling the spin‐induced quadrupole deformation by a single parameter. All spin‐dependent Hamiltonians for r... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4488978 Fri, 18 Feb 2011 01:28:29 +0100 4488978 http://www.medworm.com/index.php?rid=4488979&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000139 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4488979 Wed, 16 Feb 2011 00:00:00 +0100 4488979 http://www.medworm.com/index.php?rid=4464150&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100002 We present a generalized formulation of the Optimized Effective Potential (OEP) approach to the Self Interaction Correction (SIC) problem in Time Dependent (TD) Density Functional Theory (DFT). The formulation relies on the introduction of a double set of single electron orbitals. It allows the derivation of a generalized Slater approximation to the full OEP formulation, which extends the domain of validity of the standard Slater approximation. We discuss both formal aspects and practical applications of the new formalism and give illustrations in cluster and molecules. The new formalism provides a valuable ansatz to more elaborate (and computationally very demanding) full TD OEP and full TD SIC calculations especially in the linear domain. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4464150 Sat, 12 Feb 2011 01:05:43 +0100 4464150 http://www.medworm.com/index.php?rid=4445353&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190002 A closer look into the grand history of Annalen der Physik: themes which ccupied the minds of physicists one century ago (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4445353 Tue, 08 Feb 2011 00:34:12 +0100 4445353 http://www.medworm.com/index.php?rid=4445352&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152303 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4445352 Tue, 08 Feb 2011 00:34:09 +0100 4445352 http://www.medworm.com/index.php?rid=4445351&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152313 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4445351 Tue, 08 Feb 2011 00:34:08 +0100 4445351 http://www.medworm.com/index.php?rid=4445350&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190001 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4445350 Tue, 08 Feb 2011 00:34:08 +0100 4445350 http://www.medworm.com/index.php?rid=4445349&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201100008 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4445349 Tue, 08 Feb 2011 00:34:06 +0100 4445349 http://www.medworm.com/index.php?rid=4423741&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000162 We present a simple and natural way to derive the observed small, positive cosmological constant from the gravitational interaction of condensing fermions. In the Riemann‐Cartan spacetime, torsion gives rise to the axial–axial vector four‐fermion interaction term in the Dirac Lagrangian for spinor fields. We show that this nonlinear term acts like a cosmological constant if these fields have a nonzero vacuum expectation value. For quark fields in QCD, such a torsion‐induced cosmological constant is positive and its energy scale is only about 8 times larger than the observed value. Adding leptons to this picture could lower this scale to the observed value. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4423741 Tue, 18 Jan 2011 00:00:00 +0100 4423741 http://www.medworm.com/index.php?rid=4418633&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000113 AbstractAb‐initio calculations within density functional theory are performed to obtain a more systematic understanding of the electronic structure of iron pnictides. As a prototypical compound we study Ba0.5K0.5Fe2As2 and analyze the changes of its electronic structure when the interaction between the Fe2As2 layers and their surrounding is modified. We find strong effects on the density of states near the Fermi energy as well as the Fermi surface. The role of the electron donor atoms in iron pnictides thus cannot be understood in a rigid band picture. Instead, the bonding within the Fe2As2 layers reacts to a modified charge transfer from the donor atoms by adapting the intra‐layer Fe‐As hybridization and charge transfer in order to maintain an As3‐ valence state. (Source: Annalen ... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4418633 Tue, 18 Jan 2011 00:00:00 +0100 4418633 http://www.medworm.com/index.php?rid=4399063&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000140 AbstractBased on a recent work by Schuller et al., a geometric representation of all skewonless, non‐birefringent linear media is obtained. The derived constitutive law is based on a “core”, encoding the optical metric up to a constant. All further corrections are provided by two (anti‐)selfdual bivectors, and an “axion”. The bivectors are found to vanish if the optical metric has signature (3,1) – that is, if the Fresnel equation is hyperbolic. We propose applications of this result in the context of transformation optics and premetric electrodynamics. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4399063 Tue, 18 Jan 2011 00:00:00 +0100 4399063 http://www.medworm.com/index.php?rid=4330432&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201010465 AbstractIn this paper, a new methodology is formulated for solving the reduced Fokker‐Planck (FP) equations in high dimensions based on the idea that the state space of large‐scale nonlinear stochastic dynamic system is split into two subspaces. The FP equation relevant to the nonlinear stochastic dynamic system is then integrated over one of the subspaces. The FP equation for the joint probability density function of the state variables in another subspace is formulated with some techniques. Therefore, the FP equation in high‐dimensional state space is reduced to some FP equations in low‐dimensional state spaces, which are solvable with exponential polynomial closure method. Numerical results are presented and compared with the results from Monte Carlo simulation and those from eq... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4330432 Tue, 11 Jan 2011 01:48:14 +0100 4330432 http://www.medworm.com/index.php?rid=4330433&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201010464 AbstractThe purpose of this paper is to explain clearly why nonlocality must be an essential part of the theory of relativity. In the standard local version of this theory, Lorentz invariance is extended to accelerated observers by assuming that they are pointwise inertial. This locality postulate is exact when dealing with phenomena involving classical point particles and rays of radiation, but breaks down for electromagnetic fields, as field properties in general cannot be measured instantaneously. The problem is corrected in nonlocal relativity by supplementing the locality postulate with a certain average over the past world line of the observer. (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4330433 Mon, 10 Jan 2011 00:00:00 +0100 4330433 http://www.medworm.com/index.php?rid=4304744&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201000149 AbstractThis paper explains the multi‐orbital band structures and itinerant magnetism of the iron‐pnictide and chalcogenide superconductors. We first describe the generic band structure of a single, isolated FeAs layer. Use of its Abelian glide‐mirror group allows us to reduce the primitive cell to one FeAs unit. For the lines and points of high symmetry in the corresponding large, square Brillouin zone, we specify how the one‐electron Hamiltonian factorizes. From density‐functional theory, and for the observed structure of LaOFeAs, we generate the set of eight Fe d and As p localized Wannier functions and their tight‐binding (TB) Hamiltonian, h (k) . For comparison, we generate the set of five Fe d Wannier orbitals. The topology of the bands, i. e. allowed and avoided crossing... Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4304744 Mon, 03 Jan 2011 14:54:12 +0100 4304744 http://www.medworm.com/index.php?rid=4304743&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152301 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4304743 Mon, 03 Jan 2011 14:54:10 +0100 4304743 http://www.medworm.com/index.php?rid=4304742&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201152311 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4304742 Mon, 03 Jan 2011 14:54:09 +0100 4304742 http://www.medworm.com/index.php?rid=4304741&cid=s_37709_75_f&fid=37709&url=http%3A%2F%2Fdx.doi.org%2F10.1002%252Fandp.201190000 (Source: Annalen der Physik) Annalen der Physik journals http://www.medworm.com/rss/comments.php?id=4304741 Mon, 03 Jan 2011 14:54:08 +0100 4304741