Search

We derive the full spacetime metric of a generalized uncertainty-inspired quantum black hole. We examine a previous model of the interior in this approach and show that extending its metric to the full spacetime leads to serious issues in the asymptotic region. To remedy this, we introduce an "improved scheme" mimicking a similar prescription used in loop quantum gravity, where the quantum parameters are made momentum-dependent. Under this scheme, we rework the interior of the black hole and extend it to the full spacetime. We find that the resulting metric is asymptotically flat and its associated Kretschmann scalar is regular everywhere. We also show that the null expansion and Raychaudhuri equation are regular everywhere in this spacetime, implying that the classical singularity is resolved., Comment: 35 pages, 7 figures

We calculate the quasinormal modes of a nonsingular spherically symmetric black hole effective model with holonomy corrections. The model is based on quantum corrections inspired by loop quantum gravity. It is covariant and results in a spacetime that is regular everywhere with a parameter-dependent black bounce. Perturbations of these black holes due to massless scalar and electromagnetic fields have been previously calculated and some intriguing results were observed. For some modes, the frequency versus minimum-radius parameter trajectories were found to spiral and self-intersect in the complex plane. In addition, the spectrum of overtones has real frequencies that oscillate with increasing overtone number, and may even vanish for some overtones. We have calculated the quasinormal modes for all massless spin perturbations, including spin-1/2, and axial- and polar-gravitational. We find that the trajectory-spirals are restricted to scalar perturbations and observe some interesting overtone behaviour for gravitational perturbations. The amount of isospectrality violation in the gravitational quasinormal mode spectra is also examined., Comment: Improved clarity and added appendix (accepted version): 42 pages, 8 figures, 10 tables

We compare four loop quantum gravity inspired black hole metrics near the Planck scale. Spin 0, 1/2, 1, and 2 field perturbations on these backgrounds are studied. The axial gravitational quasinormal modes are calculated and compared. The time evolution of the ringdown is examined. We also calculate the quasinormal modes in the eikonal limit and compare with the predictions from circular null geodesics., Comment: addressed comments

Quantum atmosphere effective radii for the emission of spin-0, -1/2, -1, and -2 massless fields from Schwarzschild, Tangherlini, non-commutative geometry inspired, and polymeric black holes are calculated. The power observed from the black hole at spatial infinity taking greybody factors into account is compared to an equal-power black-body radiator of the same temperature but different effective radius. A large range of different radii are obtained for different spin fields and black holes. The equal-power black-body effective radius is not, in general, a good proxy for the location of the quantum atmosphere., Comment: 10 pages, 5 tables, 0 figures

Greybody factors are computed for massless fields of spin 0, 1/2, 1, and 2 emitted from higher-dimensional non-commutative geometry inspired black holes. Short-range potentials are used with path-ordered matrix exponentials to numerically calculate transmission coefficients. The resulting absorption cross sections and emission spectra are computed on the brane and compared with the higher-dimensional Schwarzschild-Tangherlini black hole. A non-commutative black hole at its maximum temperature in seven extra dimensions will radiate a particle flux and power of 0.72-0.81 and 0.75-0.81, respectively, times lower than a Schwarzschild-Tangherlini black hole of the same temperature. A non-commutative black hole at its maximum temperature in seven extra dimensions will radiate a particle flux and power of 0.64-0.72 and 0.60-0.64, respectively, times lower than a Schwarzschild-Tangherlini black hole of the same mass., Comment: 27 pages, 13 figures; addresses referees' comments

Quantum black hole production at the Large Hadron Collider is investigated using the horizon quantum mechanics model. This model has novel implications for how black holes might be observed in collider experiments. Black hole production is predicted to be possible below the Planck scale, thus leading to the intriguing possibility that black holes could be produced even if the Planck scale is slightly above the collider centre of mass energy. In addition, the usual anticipated resonance in the black hole mass distribution is significantly widened in this model. For values of the Planck scale above the current lower limits, the shape of the black hole mass distribution is almost independent of the Planck scale and depends more on the number of extra dimensions. These model features suggest the need for alternative search strategies in collider experiments., Comment: To be published in Phys. Rev. D

We describe a Monte Carlo event generator for the production and decay of first and second string resonances through 2 $\rightarrow$ 2 partonic and also 2-parton $\rightarrow$ $\gamma$-parton scatterings in proton-proton collisions - STRINGS version 1.00. This generator is also capable of producing QCD diparton processes. STRINGS is written in Python 2 and can be interfaced to common hadronization programs using the Les Houches Accord., Comment: version 1.00

The possibility of producing non-perturbative low-scale gravity states in collider experiments was first discussed in about 1998. The ATLAS and CMS experiments have searched for non-perturbative low-scale gravity states using the Large Hadron Collider (LHC) with a proton--proton centre of mass energy of 8 TeV. These experiments have now seriously confronted the possibility of producing non-perturbative low-scale gravity states which were proposed over 17 years ago. I will summarise the results of the searches, give a personal view of what they mean, and make some predictions for 13 TeV centre of mass energy. I will also discuss early ATLAS 13 TeV centre of mass energy results., Comment: 21 pages, 5 figures

I present an up to date set of limits on the fundamental Planck scale M_D. The best limit for each number of extra dimensions n is shown in bold font. For n = 2, M_D > 5.6 TeV; n = 3, M_D > 4.4 TeV; n = 4, M_D > 3.9 TeV; n = 5, M_D > 3.6 TeV; n = 6, M_D > 3.3 TeV; and for 6 < n < 9, M_D > 0.8 TeV., Comment: Fixed bug in CMS mono-jet limits

We study the model uncertainties on limits for quantum black hole production in dijet events from ATLAS. For models that assume a hard-disk cross section, the model uncertainty on the threshold mass limits is about 5%. If the trapped surface calculation is used for the cross section, the ATLAS mass threshold limits are below 2 TeV for all number of dimensions. Using the ATLAS data in the context of the Randall-Sundrum type-1 model gives a threshold mass lower limit of 2.84 TeV., Comment: 9 pages, 5 figures

When embedding models of noncommutative geometry inspired black holes into the peridium of large extra dimensions, it is natural to relate the noncommutativity scale to the higher-dimensional Planck scale. If the Planck scale is of the order of a TeV, noncommutative geometry inspired black holes could become accessible to experiments. In this paper, we present a detailed phenomenological study of the production and decay of these black holes at the Large Hadron Collider (LHC). Noncommutative inspired black holes are relatively cold and can be well described by the microcanonical ensemble during their entire decay. One of the main consequences of the model is the existence of a black hole remnant. The mass of the black hole remnant increases with decreasing mass scale associated with noncommutative and decreasing number of dimensions. The experimental signatures could be quite different from previous studies of black holes and remnants at the LHC since the mass of the remnant could be well above the Planck scale. Although the black hole remnant can be very heavy, and perhaps even charged, it could result in very little activity in the central detectors of the LHC experiments, when compared to the usual anticipated black hole signatures. If this type of noncommutative inspired black hole can be produced and detected, it would result in an additional mass threshold above the Planck scale at which new physics occurs., Comment: 21 pages, 7 figures

Tidal-charged black hole solutions localized on a three-brane in the five-dimensional gravity scenario of Randall and Sundrum have been known for some time. The solutions have been used to study the decay, and growth, of black holes with initial mass of about 10 TeV. These studies are interesting in that certain black holes, if produced at the Large Hadron Collider, could live long enough to leave the detectors. I examine the production of tidal-charged black holes at the Large Hadron Collider and show that it is very unlikely that they will be produced during the lifetime of the accelerator., Comment: addressed reviewer comments

In low-scale gravity scenarios, quantum black holes could be produced at the Large Hadron Collider (LHC) provided the Planck scale is not higher than a few TeV. Based on fundamental principles and a few basic assumptions, we have constructed a model for quantum black hole production and decay in proton-proton collisions. By performing a detailed particle-level simulation at LHC energies, we have estimated cross sections and branching fractions for final-state particle topologies that would uniquely identify quantum black holes in LHC detectors. If the Planck scale is about a TeV, even with the most pessimistic assumptions, the rates for quantum black hole production are estimated to be above backgrounds, and some of the final-particle states are not found in Standard Model processes. Our results could form the starting point for a detailed investigation of quantum black holes by the LHC experiments., Comment: bugs in some branching fractions fixed, updates based on comments

We describe the Monte Carlo event generator for quantum black hole production and decay in proton-proton collisions -- QBH version 1.03., Comment: updated to version 1.03, now uses pythia 8.150, may not be backward compatable with older versions of pythia8

It is a challenge to explain why neutrinos are so light compared to other leptons. Small neutrino masses can be explained if right-handed fermions propagate in large extra dimensions. Fermions propagating in the bulk would have implications on Higgs boson decays. If the Higgs boson is discovered at the Large Hadron Collider (LHC), a detailed analysis may reveal the presence of large extra dimensions. This paper reviews the status of large extra-dimensional models in the context of the current limits on Higgs boson masses and the fundamental Planck scale in extra dimensions., Comment: Addressed comments by reviewer

In TeV-scale gravity scenarios with large extra dimensions, black holes may be produced at future colliders. Good arguments have been made for why general relativistic black holes may be just out of reach of the Large Hadron Collider (LHC). However, in weakly-coupled string theory, highly excited string states - string balls - could be produced at the LHC with high rates and decay thermally, not unlike general relativistic black holes. In this paper, we simulate and study string ball production and decay at the LHC. We specifically emphasize the experimentally-detectable similarities and differences between string balls and general relativistic black holes at a TeV scale., Comment: expanded discussion on backgrounds

Black holes could be produced at the Large Hadron Collider in TeV-scale gravity scenarios. We discuss missing energy mechanisms in black hole production and decay in large extra-dimensional models. In particular, we examine how graviton emission into the bulk could give the black hole enough recoil to leave the brane. Such a perturbation would cause an abrupt termination in Hawking emission and result in large missing-energy signatures., Comment: addressed reviewer comments and updated references

The cross section for black hole production in hadron colliders is calculated using a factorization hypothesis in which the parton-level process is integrated over the parton density functions of the protons. The mass, spin, charge, colour, and finite size of the partons are usually ignored. We examine the effects of parton electric charge on black hole production using the trapped-surface approach of general relativity. Accounting for electric charge of the partons could reduce the black hole cross section by one to four orders of magnitude at the Large Hadron Collider. The cross section results are sensitive to the Standard Model brane thickness. Lower limits on the amount of energy trapped behind the event horizon in the collision of charged particles are also calculated., Comment: corrected typo in figure 1b; added some clarification in 3 places; 21 pages, 9 figures, JHEP3 format

Black hole production at the Large Hadron Collider (LHC) was first discussed in 1999. Since then, much work has been performed in predicting the black hole cross section. In light of the start up of the LHC, it is now timely to review the state of these calculations. We review the uncertainties in estimating the black hole cross section in higher dimensions. One would like to make this estimate as precise as possible since the predicted values, or lower limits, obtain for the fundamental Planck scale and number of extra dimensions from experiments will depend directly on the accuracy of the cross section. Based on the current knowledge of the cross section, we give a range of lower limits on the fundamental Planck scale that could be obtained at LHC energies., Comment: 28 pages, 9 figures, LaTeX; added references, corrected typos, expanded discussion