125886851
Rotating black holes at colliders
118501826
Phenomenology of universal extra dimensions with bulk-masses and brane-localized terms
A bstractWe present a general model with universal extra dimensions in the presence of the bulk fermion masses and boundary localized kinetic terms, which are generically allowed by symmetries of five dimensional gauge theory. We compute current bounds on the size of allowed universal bulk mass and universal brane-localized terms.
44257648
Higgs inflation is still alive after the results from BICEP2.
The observed value of the Higgs boson mass indicates that the Higgs potential becomes small and flat at the scale around 10(17)  GeV. Having this fact in mind, we reconsider the Higgs inflation scenario proposed by Bezrukov and Shaposhnikov. It turns out that the nonminimal coupling ξ of the Higgs squared to the Ricci scalar can be smaller than 10. For example, ξ=7 corresponds to the tensor-to-scalar ratio r≃0.2, which is consistent with the recent observation by BICEP2.
122705764
Phenomenology of the heavy B H in a littlest Higgs model
119338290
Neutrino Mass from R-parity Violation in Split Supersymmetry
We investigate how the observed neutrino data can be accommodated by R-parity violation in Split Supersymmetry. The atmospheric neutrino mass and mixing are explained by the bilinear parameters ξi inducing the neutrino-neutralino mixing as in the usual low-energy supersymmetry. Among various one-loop corrections, only the quark-squark exchanging diagrams involving the order-one trilinear couplings λ'i23,i32 can generate the solar neutrino mass and mixing if the scalar mass mS is not larger than 109 GeV. This scheme requires an unpleasant hierarchical structure of the couplings, e.g., λi23,i32 ~ 1, λ'i3310−4 and ξi10−6. On the other hand, the model has a distinct collider signature of the lightest neutralino which can decay only to the final states, liW(*) and νZ(*), arising from the bilinear mixing. Thus, the measurement of the ratio; Γ(eW(*)):Γ(μW(*)):Γ(τW(*)) would provide a clean probe of the small reactor and large atmospheric neutrino mixing angles as far as the neutralino mass is larger than 62 GeV.
14695226
Rotating Black Holes at Future Colliders
We consider the production and decay of TeV-scale black holes. Evaluation of the production cross section of higher dimensional rotating black holes is made. The master field equation for general spin-$s$ fields confined on brane world is derived. For five-dimensional (Randall-Sundrum) black holes, we obtain analytic formulae for the greybody factors in low frequency expansion.
118577921
The volume of the past light-cone and the Paneitz operator
We study a conjecture involving the invariant volume of the past light-cone from an arbitrary observation point back to a fixed initial value surface. The conjecture is that a fourth order differential operator which occurs in the theory of conformal anomalies gives 8π when acted upon the invariant volume of the past light-cone. We show that an extended version of the conjecture is valid for an arbitrary homogeneous and isotropic geometry. First order perturbation theory about flat spacetime reveals a violation of the conjecture which, however, vanishes for any vacuum solution of the Einstein equation. These results may be significant for constructing quantum gravitational observables, for quantifying the back-reaction on spacetime expansion and for alternate gravity models which feature a timelike vector field.
118606531
Quantum gravity corrections to the conformally coupled scalar self-mass-squared on de Sitter background
We evaluate one loop quantum gravity corrections to the conformally coupled (CC) scalar self-mass-squared on a locally de Sitter background. In this paper we consider only the conformal-conformal interaction part of the self-mass-squared. This complements the minimal-minimal part worked out in the previous paper [E. O. Kahya and R. P. Woodard, Phys. Rev. D 76, 124005 (2007), arXiv: 0709.0536], and we will add the minimal-conformal part in a follow-up paper to complete the full self-mass-squared at one loop order. The computation is performed using dimensional regularization and the results are fully renormalized by absorbing divergences with counterterms. The finite results can give rise to quantum corrections to the CC scalar mode functions and therefore to their power spectra.
119164286
Exact 4-point scattering amplitude of the superconformal Schrödinger Chern-Simons theory
We consider the non-relativistic superconformal U(N) × U(N) Chern-Simons theory with level (k,−k) possessing fourteen supersymmetries. We obtain an exact four-point scattering amplitude of the theory to all orders in 1/N and 1/k and prove that the scattering amplitude becomes trivial when k = 1 and 2. We confirm this amplitude to one-loop order by using an explicit field theoretic computation and show that the beta function for the contact interaction vanishes to the one-loop order, which is consistent with the quantum conformal invariance of the underlying theory.
119287976
Solving the Effective Field Equations for the Newtonian Potential
Loop corrections to the gravitational potential are usually inferred from scattering amplitudes, which seems quite different from how the linearized Einstein equations are solved with a static, point mass to give the classical potential. In this study we show how the Schwinger–Keldysh effective field equations can be used to compute loop corrections to the potential in a way which parallels the classical treatment. We derive explicit results for the one-loop correction from the graviton self-energy induced by a massless, minimally coupled scalar.
96425170
Structure formation in a nonlocally modified gravity model
We study a nonlocally modified gravity model proposed by Deser and Woodard which gives an explanation for current cosmic acceleration. By deriving and solving the equations governing the evolution of the structure in the Universe, we show that this model predicts a pattern of growth that differs from standard general relativity (+dark energy) at the 10-30% level. These differences will be easily probed by the next generation of galaxy surveys, so the model should be tested shortly.