120492588
Spin-Rotation Coupling in the Teleparallelism Description in High Speed Rotation System
The spin-rotation coupling can be described by the torsion axial-vector and teleparallelism of general relativity. In a large scale distance, with a high rotating velocity, the tangent velocity will exceed the velocity of light. To overcome that difficulty, we choose a nonuniform and position-dependent angular velocity, e.g. $\Omega(\rho)=\frac{\Omega}{\sqrt[K]{1+(\Omega\rho/C)^{K}}}$. Based on this choice, we find that the tangent velocity will be less than the speed of light at infinity and never be meaningless. Moreover, the new rotation-spin coupling is derived. And in the case of K=2, it will be consistent with the previous result with the constant angular velocity.
119336471
Tunnelling Effect of Two Horizons from a Gibbons-Maeda Black Hole
We study the thermal characters of the inner horizon of a Gibbons–Maeda black hole. In order to satisfy the Nernst theorem of the third law, the entropy of the black hole with two horizons must depend not only on the area of the outer horizon but also on the area of the inner horizon. Then the temperature of the inner horizon is calculated. Lastly, the tunnelling effect including the inner horizon of a Gibbons–Maeda black hole is investigated. We also calculate the tunnelling rate of the outer horizon Γ+ and the inner horizon Γ-. The total tunnelling rate Γ should be the product of the rates of the outer and inner horizon, Γ = Γ+ Γ-. It is found that the total tunnelling rate is in agreement with the Parikh's standard result, Γ → exp(ΔSBH), and there is no information loss.
117555639
Hawking Radiation via Tunnelling from Arbitrarily Dimensional Schwarzschild Black Holes
We extend Parikh's recent work to the arbitrarily dimensional Schwarzschild black holes whose Arnowitt–Deser–Misner (ADM) mass is identical to its mass parameter. We view Hawking radiation as a tunnelling process across the event horizon. From the tunnelling probability we also find a leading correction to the semiclassical emission rate. The result consists with an underlying unitary theory.
124059954
Hawking radiation of a uniformly accelerating black hole
In this paper, we study the Hawking radiation via tunnelling from a uniformly accelerating black hole. Although the Bekenstein–Hawking entropy is proportional also to the area of the event horizon, the radius of it, rH, is a function of θ, which leads to the difficulties in the calculation of the emission rate. In order to overcome the mathematical difficulties, we propose a new technique to calculate the emission rate and the result obtained is reasonable.
122941988
Neutrino Oscillations in the de Sitter and the Anti-de Sitter Space-Time
General expressions of the neutrino oscillation phase in the generally static space-time with spherical symmetry are given. The effect of the gravitational field on the oscillation length is embodied in the gravitational red shift factor. We find that a blue shift of the oscillation length takes place when the neutrino travels out of the gravitational field. Then, we discuss the variation of the oscillation length influenced by the cosmological constant. In the de Sitter space-time, the positive cosmological constant prolongs the oscillation length. And, in the anti-de Sitter space-time, the negative cosmological constant shortens it as expected.
123206975
Neutrino Oscillations in the Robertson-Walker Metric and the Cosmological Blue Shift of the Oscillation Length
The Doppler effect of the neutrino oscillation length in the flat space is discussed. When the observer travels away from the source, the oscillation length decreases. Moreover, the mass neutrino oscillation in the Robertson-Walker metric is studied, and the general equations of the oscillation phases are given. We obtain the relation between the phase and the scale factor. The expansion of the universe leads to the reduction of the oscillation length (blue shift), which is contrary to the red shift of the light ray.
118671365
Technipion Limits from LHC Higgs Searches
LHC searches for the standard model Higgs Boson in di-photon or di-tau decay modes place strong constraints on the light top-pion state predicted in technicolor models that include colored technifermions. Compared with the standard Higgs Boson, the top-pions have an enhanced production rate (largely because the technipion decay constant is smaller than the weak scale) and also enhanced branching ratios into di-photon and di-tau final states (largely due to the suppression of WW decays of the technipions). These factors combine to make the technipions more visible in both channels than a standard model Higgs would be. Hence, the recent ATLAS and CMS searches for Higgs bosons exclude the presence of technipions with masses from 110 GeV to nearly twice the top-quark mass in technicolor models that (a) include colored technifermions (b) feature topcolor dynamics and (c) have technicolor groups with three or more technicolors. For certain models, the limits also apply out to higher technipion masses or down to the minimum number of technicolors. The limits may be softened somewhat in models where extended technicolor plays a significant role in producing the top quark's mass. Additional LHC data on di-tau and di-photon final states will be extremely valuable in further exploring technicolor parameter space.
55805244
LHC constraints on a Higgs boson partner from an extended color sector
the presence of a heavy Higgs and to the detailed properties of the 125 GeV Higgs will further constrain the properties of the new heavy s scalar. Since the renormalizable coloron model may contain spectator fermions to remove anomalies, we examine several representative scenarios with different numbers of spectator fermions. Our results are summarized in plots that overlay the current exclusion limits on the s boson with the projected sensitivity of the ffiffiffi s p ¼ 14TeV LHC to the new state. We find that the upcoming LHC searches should be sensitive to an s scalar of mass less than 1 TeV for essentially all of the model parameter space in which the h state differs from the Higgs boson of the SM. More precisely, unless the mixing between the weak doublet and weak singlet gauge-eigenstate scalars is zero, the 14 TeV LHC will be sensitive to the presence of the nonstandard heavy s state that is characteristic of the renormalizable coloron model.
119298728
Gravitational Interaction of Higgs Boson and Weak Boson Scattering
With the LHC discovery of a 125 GeV Higgs-like boson, we study the gravitational interaction of the Higgs boson via the unique dimension-four operator involving the Higgs doublet and scalar curvature, xi HyHR, with nonminimal coupling xi. This Higgs portal term can be transformed away in the Einstein frame and induces gauge-invariant effective interactions in the Higgs sector. We study the weak boson scattering in the Einstein frame and explicitly demonstrate the longitudinal-Goldstone boson equivalence theorem in the presence of xi coupling. With these, we derive a perturbative unitarity bound on the Higgs gravitational coupling xi in the Einstein frame, which is stronger than that inferred from the LHC Higgs measurements. We further study xi -dependent weak boson scattering cross sections at the TeV scale and propose a new LHC probe of Higgs-gravity coupling xi via weak boson scattering experiments.
119190318
Analytic fermionic Green’s functions from holography
We find exact, analytic solutions of the Dirac equation for a charged, massless fermion in the background of a charged, dilatonic black hole in AdS_5. The black hole descends from type IIB supergravity, where it describes D3-branes with equal angular momenta in two of the three independent planes of rotation orthogonal to the world-volume. The Green's function near the Fermi surface for a strongly coupled fermionic system can be extracted holographically from an exact solution of the Dirac equation at zero frequency but nonzero momentum. There can be several Fermi momenta, and they take the form k_F=q-n-1/2 (in units of the chemical potential), where q is the charge of the spinor, and n is a non-negative integer that labels the Fermi surfaces. Much as for holographic Fermi surfaces based on the Reissner-Nordstrom-AdS_5 solution, the dispersion relation of the excitations near the Fermi surface is determined by the geometry close to the horizon, and one can obtain Fermi liquid, marginal Fermi liquid, and non-Fermi liquid behaviors depending on the value of k_F.
119037865
Analytic quantum critical points from holography
We find exact, analytic solutions of the Klein-Gordon equation for a scalar field in the background of the extremal Reissner-Nordstrom-AdS_5 black hole. The Green's function near a quantum critical point for a strongly coupled system can be extracted holographically from an exact solution for the scalar at zero frequency (\omega), but arbitrary momentum (k), mass, and charge. By examining the Green's function near \omega=0, there are two types of instability: the first one is triggered by a zero mode, and gives a hybridized critical point; the second one is triggered by the instability of the IR geometry, and gives a bifurcating critical point. The two types of instability can happen at the same time, and give a mixed critical point. Without tuning an extra parameter, only the second type of instability can happen at k=0. At the critical point with the superfluid velocity, the scalar can develop either type of instability, depending on the parameters. The zero mode can also be obtained by tuning a double trace deformation. The phase diagrams can be analytically drawn.