115459673
LIGHTCONE FLUCTUATIONS AND EXTRA DIMENSIONS
118496881
Perturbative Correction to Transverse Ward—Takahashi Relation for the Vertor Vertex
We re-derive exactly the transverse Wark-Takahashi relation for the vector vertex in momentum space,The result shows that this transverse Ward-Takahashi relation in momentum space involves a perturbative correction term.We demonstrate explicitly that this transverse Ward-Takahashi relation is satisfied indeed at one-loop order.
118525095
Lamb shift for static atoms outside a Schwarzschild black hole
We study, by separately calculating the contributions of vacuum fluctuations and radiation reaction to the atomic energy level shift, the Lamb shift of a static two-level atom interacting with real massless scalar fields in the Boulware, Unruh, and Hartle-Hawking vacuums outside a Schwarzschild black hole. We find that in the Boulware vacuum, the Lamb shift gets a correction arising as a result of the backscattering of vacuum field modes off the space-time curvature, which is reminiscent of the correction to the Lamb shift induced by the presence of cavities. However, when the Unruh and Hartle-Hawking vacua are concerned, our results show that the Lamb shift behaves as if the atom were irradiated by a thermal radiation or immersed in a thermal bath at the Hawking temperature, depending on whether the scalar field is in the Unruh or the Hartle-Hawking vacuum. Remarkably, the thermal radiation is always backscattered by the space-time geometry.
119913697
BLACK-HOLE ENTROPY AND HORIZON AREA
119090796
Fulling–Davies–Unruh effect and spontaneous excitation of an accelerated atom interacting with a quantum scalar field
Abstract We investigate, from the point of view of a coaccelerated frame, the spontaneous excitation of a uniformly accelerated two-level atom interacting with a scalar field in a thermal state at a finite temperature T and show that the same spontaneous excitation rate for the uniformly accelerated atom in the Minkowski vacuum obtained in the inertial frame can only be recovered in the coaccelerated frame assuming a thermal bath at the Fulling–Davies–Unruh temperature T FDU = a / 2 π for what appears to be the Minkowski vacuum to the inertial observer. Our discussion provides another example of a physical process different from those examined before in the literature to better understand the Fulling–Davies–Unruh effect.
119124346
Unruh effect and entanglement generation for accelerated atoms near a reflecting boundary
We study, in the framework of open systems, the entanglement generation of two independent uniformly accelerated atoms in interaction with the vacuum fluctuations of massless scalar fields subjected to a reflecting plane boundary. We demonstrate that, with the presence of the boundary, the accelerated atoms exhibit distinct features from static ones in a thermal bath at the corresponding Unruh temperature in terms of the entanglement creation at the neighborhood of the initial time. In this sense, accelerated atoms in vacuum do not necessarily have to behave as if they were static in a thermal bath at the Unruh temperature.
122050852
VECTOR PAIRING AND FLUCTUATION-INDUCED CHERN-SIMONS TERM IN ANYON SUPERCONDUCTIVITY
Assuming some sorts of vector pairing in high-temperature superconductivity, we show how the topological Chern-Simons term can be generated dynamically due to quantum fluctuations in a BCS-type four-fermion model. This fluctuation-induced Chern-Simons term provides a natural way to incorporate fractional statistics and thus a more direct connection with anyon superconductivity.
125027666
Restudies of Searching for 1~(-+) Exotic State
In order to convenience for the data analysis of BES some new relations which can be used to search for the 1~(-+) exotic state in J/φ→ωX, X→KKπ have been obtained. How to search for the 1~(-+) exotic state in the three--step two--body hadronic decay process J/φ→ωX, X→KK~*, K~*→Kπ is also discussed.
109933831
New formulation of Horava–Lifshitz quantum gravity as a master constraint theory
Abstract Both projectable and non-projectable versions of Horava–Lifshitz gravity face serious challenges. In the non-projectable version, the constraint algebra is seemingly inconsistent. The projectable version lacks a local Hamiltonian constraint, thus allowing for an extra scalar mode which can be problematic. A new formulation of non-projectable Horava–Lifshitz gravity, naturally realized as a representation of the master constraint algebra studied by loop quantum gravity researchers, is presented. This yields a consistent canonical theory with first class constraints. It captures the essence of Horava–Lifshitz gravity in retaining only spatial diffeomorphisms (instead of full space–time covariance) as the physically relevant non-trivial gauge symmetry; at the same time the local Hamiltonian constraint needed to eliminate the extra mode is equivalently enforced by the master constraint.
10829609
Halo-shape and relic-density exclusions of Sommerfeld-enhanced dark matter explanations of cosmic ray excesses.
Dark matter with Sommerfeld-enhanced annihilation has been proposed to explain observed cosmic ray positron excesses in the 10 GeV to TeV energy range. We show that the required enhancement implies thermal relic densities that are too small to be all of dark matter. We also show that the dark matter is sufficiently self-interacting that observations of elliptical galactic dark matter halos exclude large Sommerfeld enhancement for light force carriers. Resonant Sommerfeld enhancement does not modify these conclusions, and the astrophysical boosts required to resolve these discrepancies are disfavored, especially when significant self-interactions suppress halo substructure.
122878082
Induced Topological Terms, Hidden Local Symmetry, and Anyon Superconductivity
We show how the topological Chern-Simons term in three dimensions and the θ-term, in four dimensions can be dynamically generated due to quantum fluctuations in Nambu-Jona-Lasinio models. These results give a vivid demonstration of hidden local symmetry at work. The fluctuation-induced Chern-Simons term provides a natural way to incorporate fractional statistics and thus a more direct connection with anyon superconductivity. Possible phenomenological implications of this approach in particle physics are also discussed.