The Static Quantum Multiverse

We consider the multiverse in the intrinsically quantum mechanical framework recently proposed in Refs. [1,2]. By requiring that the principles of quantum mechanics are universally valid and that physical predictions do not depend on the reference frame one chooses to describe the multiverse, we find that the multiverse state must be static---in particular, the multiverse does not have a beginning or end. We argue that, despite its naive appearance, this does not contradict observation, including the fact that we observe that time flows in a definite direction. Selecting the multiverse state is ultimately boiled down to finding normalizable solutions to certain zero-eigenvalue equations, analogous to the case of the hydrogen atom. Unambiguous physical predictions would then follow, according to the rules of quantum mechanics.Comment: 27 pages, 2 figures; a typo in the abstract correcte

On the spectroscopy of quantum dots in microcavities

At the occasion of the OECS conference in Madrid, we give a succinct account of some recent predictions in the spectroscopy of a quantum dot in a microcavity that remain to be observed experimentally, sometimes within the reach of the current state of the art.Comment: OECS11 Conference proceedings, in editor style. 4 pages, 1 figure. Animations provided separatel

SU(2)/Z2SU(2)/Z_2 symmetry of the BKT transition and twisted boundary conditio n

Berezinskii-Kosterlitz-Thouless (BKT) transition, the transition of the 2D sine-Gordon model, plays an important role in the low dimensional physics. We relate the operator content of the BKT transition to that of the SU(2) Wess-Zumino-Witten model, using twisted boundary conditions. With this method, in order to determine the BKT critical point, we can use the level crossing of the lower excitations than the periodic boundary case, thus the convergence to the transition point is highly improved. Then we verify the efficiency of this method by applying to the S=1,2 spin chains.Comment: LaTex2e,, 33 pages, 14 figures in eps file

Anisotropic phonon DOS: the application of Rietveld and Mossbauer texture analysis in aligned powders

While synthesizing the single crystals of novel materials is not always feasible, orienting the layered polycrystals becomes an attractive method in the studies of angular dependencies of inelastic scattering of x-rays or neutrons. Putting in use the Rietveld analysis of layered structures in novel manganites and cuprates we develop the studies of their anisotropic properties with oriented powders instead of single crystals. Densities of phonon states (DOS) and atomic thermal displacememts (ATD) are anisotropic in the A-site ordered manganites LnBaMn2Oy of both y=5 and y=6 series (Ln=Y, La, Sm, Gd). We establish the angular dependence of DOS on textures of arbitrary strengths, link the textures observed by x-ray and gamma-ray techniques, and solve the problem of disentanglement of Goldanskii-Karyagin effect (GKE) and texture in Moessbauer spectra.Comment: 6 pages; 5 figures, revise

Warped Domain Wall Fermions

We consider Kaplan's domain wall fermions in the presence of an Anti-de Sitter (AdS) background in the extra dimension. Just as in the flat space case, in a completely vector-like gauge theory defined after discretizing this extra dimension, the spectrum contains a very light charged fermion whose chiral components are localized at the ends of the extra dimensional interval. The component on the IR boundary of the AdS space can be given a large mass by coupling it to a neutral fermion via the Higgs mechanism. In this theory, gauge invariance can be restored either by taking the limit of infinite proper length of the extra dimension or by reducing the AdS curvature radius towards zero. In the latter case, the Kaluza-Klein modes stay heavy and the resulting classical theory approaches a chiral gauge theory, as we verify numerically. Potential difficulties for this approach could arise from the coupling of the longitudinal mode of the light gauge boson, which has to be treated non-perturbatively

High energy electrons beyond 100 GEV observed by emulsion chamber

Much efforts have been expended to observe the spectrum of electrons in the high energy region with large area emulsion chambers exposed at balloon altitudes, and now 15 electrons beyond 1 TeV have been observed. The observed integral flux at 1 TeV is (3.24 + or - 0.87)x10(-5)/sq m sec sr. The statistics of the data around a few hundred GeV are also improving by using new shower detecting films of high sensitivity. The astrophysical significance of the observed spectrum are discussed for the propagation of electrons based on the leaky box and the nested leaky box model

Theory of Transport Properties in the p-wave Superconducting State of Sr2RuO4 - A Microscopic Determination of the Gap Structure -

We provide a detailed quantitative analysis of transport properties in the p-wave superconducting state of Sr2RuO4. Specifically, we calculate ultrasound attenuation rate and electronic thermal conductivity within the mean field approximation. The impurity scattering of the quasi-particles are treated within the self-consistent T-matrix approximation, and assumed to be in the unitarity limit. The momentum dependence of the gap function is determined by solving the Eliashberg equation for a three-band Hubbard model with the realistic electronic structure of Sr2RuO4. On the basis of the microscopic theory, we can naturally expect nodal structures along the c-axis on the cylindrical Fermi surfaces, even if we assume the chiral pairing state (i.e., \Delta(k) \sim k_x \pm {\rm i} k_y). Consequently, we obtain the temperature dependence of the transport coefficients in agreement with the experimental results. We can clarify that actually the thermal excitations on the passively superconducting bands contribute significantly to the thermal conductivity in a wide temperature range, in contrast to the case of other physical quantities.Comment: 12 pages, 7 figures, submitted to J. Phys. Soc. Jp