119288619
Black holes and the LHC: A review
Abstract In low-scale gravity models, a particle collider with trans-Planckian collision energies can be an ideal place for producing black holes because a large amount of energy can be concentrated at the collision point, which can ultimately lead to black hole formation. In this article, the theoretical foundation for microscopic higher dimensional black holes is reviewed and the possible production and detection at the LHC is described and critically examined.
125886851
Rotating black holes at colliders
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.
16076999
Minimal extra dimensional cosmology from hidden sector gauge theory
We build a minimal cosmological model in higher dimensions based on a hidden sector gauge theory, which is less constrained by the low energy experiments. In this model we introduce the minimal non-Abelian gauge symmetry SU(2) in the fifth spatial dimension. The inflaton field which is identified as a part of higher dimensional gauge boson is protected by the gauge symmetry. Thus the inflaton potential is fully radiatively generated by the gauge self interaction alone without introducing any ad hoc field. and is flat enough to drive slow-roll inflation. We find that in the regime of perturbative gauge interaction and large compactification radius the anticipated magnitude of the curvature perturbation power spectrum and the value of the corresponding spectral index are in perfect agreement with the recent observations in a wide range of the model parameters. The model also predicts a large fraction of the gravitational waves, negligible non-Gaussianity, and high enough reheating temperature.
14086679
Implication of Brane fluctuations to indirect collider signals
We study the effect of brane fluctuation on the indirect signals of high energy colliders. Brane fluctuation could act as a regulator of divergent expression of infinite tower of Kaluza-Klein graviton effects. The phenomenological parameter λ, introduced by Hewett, is shown to be determined in our setting, and its dramatic behaviors depending on the D = 4+δ dimensional gravitation scale MD, `softening parameter' Δ, and (s)1/2 of collider are presented. The present exclusion bounds from the processes e+e−→γγ and p→e+e−,γγ(γ) are considered within the parameter space (MD,Δ) with respect to the number of extra dimensions.
122705764
Phenomenology of the heavy B H in a littlest Higgs model
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.
119239609
Alternate definitions of loop corrections to the primordial power spectra
We consider two different definitions for loop corrections to the primordial power spectra. One of these is to simply correct the mode functions in the tree order relations using the linearized effective field equations. The second definition involves the spatial Fourier transform of the 2-point correlator. Although the two definitions agree at tree order, we show that they disagree at one loop using the Schwinger-Keldysh formalism, so there are at least two plausible ways of loop correcting the tree order result. We discuss the advantages and disadvantages of each.
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.
21452649
Scalar Contribution to the Graviton Self-Energy during Inflation
We use dimensional regularization to evaluate the one loop contribution to the graviton self-energy from a massless, minimally coupled scalar on a locally de Sitter background. For noncoincident points our result agrees with the stress tensor correlators obtained recently by Perez-Nadal, Roura, and Verdaguer. We absorb the ultraviolet divergences using the R{sup 2} and C{sup 2} counterterms first derived by 't Hooft and Veltman, and we take the D=4 limit of the finite remainder. The renormalized result is expressed as the sum of two transverse, fourth order differential operators acting on nonlocal, de Sitter invariant structure functions. In this form it can be used to quantum correct the linearized Einstein equations so that one can study how the inflationary production of infrared scalars affects the propagation of dynamical gravitons and the force of gravity.
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.