TeV-scale Black Holes Research Articles

Possibility of hypothetical stable micro black hole production at future 100 TeV collider

We study the phenomenology of TeV-scale black holes predicted in theories with large extra dimensions, under the further assumption that they are absolutely stable. Our goal is to present an exhaustive analysis of safety of the proposed 100 TeV collider, as it was done in the case of the LHC. We consider the theories with different number of extra dimensions and identify those for which a possible accretion to macroscopic size would have timescales shorter than the lifetime of the Solar system. We calculate the cross sections of the black hole production at the proposed 100 TeV collider, the fraction of the black holes trapped inside the Earth and the resulting rate of capture inside the Earth via an improved method. We study the astrophysical consequences of stable micro black holes existence, in particular its influence on the stability of white dwarfs and neutron stars. We obtain constraints for the previously unexplored range of higher-dimensional Planck mass values. Several astrophysical scenarios of the micro black hole production, which were not considered before, are taken into account. Finally, using the astrophysical constraints we consider the implications for future 100 TeV terrestrial experiments. We exclude the possibility of the charged stable micro black holes production.

Natural cutoffs effect on charged rotating TeV-scale black hole thermodynamics

We study the thermodynamics of charged rotating black hole in large extra dimensions scenario where quantum gravity effects are taken into account. We consider the effects of minimal length, minimal momentum, and maximal momentum as natural cutoffs on the thermodynamics of charged rotating TeV-scale black holes. In this framework, the effect of the angular momentum and charge on the thermodynamics of the black hole are discussed. We focus also on frame dragging and Sagnac effect of the micro black holes.

Quantum gravity effects on charged microblack holes thermodynamics

The charged black hole thermodynamics is corrected in terms of the quantum gravity effects. Most of the quantum gravity theories support the idea that near the Planck scale, the standard Heisenberg uncertainty principle should be reformulated by the so-called Generalized Uncertainty Principle (GUP) which provides a perturbation framework to perform required modifications of the black hole quantities. In this paper, we consider the effects of the minimal length and maximal momentum as GUP type I and the minimal length, minimal momentum and maximal momentum as GUP type II on thermo dynamics of the charged TeV-scale black holes. We also generalized our study to the universe with the extra dimensions based on the ADD model. In this framework, the effect of the electrical charge on thermodynamics of the black hole and existence of the charged black hole remnants as a potential candidate for the dark matter particles are discussed.

Charged Massive Particle’s Tunneling from Charged Nonrotating Microblack Hole

In the tunneling framework of Hawking radiation, charged massive particle’s tunneling in charged nonrotating TeV-scale black hole is investigated. To this end, we consider natural cutoffs as a minimal length, a minimal momentum, and a maximal momentum through a generalized uncertainty principle. We focus on the role played by these natural cutoffs on the luminosity of charged nonrotating microblack hole by taking into account the full implications of energy and charge conservation as well as the backscattered radiation.

MicroBlack Holes Thermodynamics in the Presence of Quantum Gravity Effects

Black hole thermodynamics is corrected in the presence of quantum gravity effects. Some phenomenological aspects of quantum gravity proposal can be addressed through generalized uncertainty principle (GUP) which provides a perturbation framework to perform required modifications of the black hole quantities. In this paper, we consider the effects of both a minimal measurable length and a maximal momentum on the thermodynamics of TeV-scale black holes. We then extend our study to the case that there are all natural cutoffs as minimal length, minimal momentum, and maximal momentum simultaneously. We also generalize our study to the model universes with large extra dimensions (LED). In this framework existence of black holes remnants as a possible candidate for dark matter is discussed. We study probability of black hole production in the Large Hadronic Collider (LHC) and we show this rate decreasing for sufficiently large values of the GUP parameter.

Spacetime dimensionality and logarithmic prefactor in the black hole entropy relation

We study the relation between the existence of the logarithmic prefactor and spacetime dimensionality in black hole entropy relation by a detailed study of a TeV-scale black hole entropy. In a model universe with large extra dimensions and within the Generalized Uncertainty Principle (GUP) framework, we show that probability of black hole production in the Large Hadronic Collider (LHC) decreases for sufficiently large values of the GUP parameter. In this regard, even observation of micro-black holes may be suppressed at TeV energy scale. We determine also the GUP parameter in an extra dimensional scenario by comparing black hole entropy calculated within the GUP and loop quantum gravity frameworks.

The stability of mesons near event horizon of black hole

SUMMARY AND CONCLUSION In this paper first we compared entropies of final states in Dirac fields as well as in scalar fields. Next we concluded that near black hole mesons are stable. After that we compared the total cross section for mesons produced from one black hole. We saw that the more the mass of the quark within the hadrons, the lower is the cross section. Finally we calculated the resulting informa-tion transformation from the collapsing matter to the state of outgoing Hawking radiation for mesons. We observe that due to the deviation of the f from unity, some of information is lost in black holes. REFERENCES Ahn D (2006). Final state boundary condition of the Schwarzschild black hole. Phys. Rev. D. 74, 084010. Ahn D (2007). Control of black hole evaporation? JHEP. 0703: 021. Zomorrodian et al. 1053 n n u -Schuller I (2008). Black hole final state for the Dirac fields In Schwarzschild spacetime. JHEP. 0806: 062. Argyres PC, Dimopoulos S, March-Russell J (1998). Black Holes and Sub-millimeter Dimensions. Phys. Lett., B441: 96. Chamblin A, Cooper F, Nayak GC (2009).Top Quark Production from Black Holes at the CERN LHC. Phys. Lett., B672: 147-151. Cooper F, Mottola E, Nayak GC (2003). Minijet Initial Conditions For Non-Equilibrium Parton Evolution at RHIC and LHC. Phys. Lett. B, 555: 181. Cooper F, Nayak GC (2004). Interaction of a TeV scale black hole with the quark-gluon plasma at CERN LHC. Phys. Rev. D. 69, 065010. Deutsch D (1991). Quantum mechanics near closed timelike lines. Phys. Rev. D., 44: 3197. Dimopoulos GC, Landsberg G (2001). Black Holes at the Large Hadron Collider. Phys. Rev. Lett., 87: 161602. Ge HX, Shen GY (2005). Reconsidering the black hole final state in Dirac fields. Phys.Lett., B612: 61-64. Giddings SB, Thomas S (2002). High energy colliders as black hole factories: end of short distance physics. Phys. Rev. D., 65: 056010. Gottesman D, Preskill J (2004). Comment on The black hole final JHEP., 0403: 026. Hawking SW (1973). Particle creation by black holes. Common.Math. Phys., 43: 199. Hawking SW (1974). Black-hole evaporation. Nature, 248: 30. Hawking SW (1976). Breakdown of predictability in gravitational collapse. Phys. Rev. D., 14: 2466. Horowitz GT, Maldacena J (2004). black hole final state. J. High. Energy. Phys., 02: 008. Millers DE (2004). Entropy for $SU(3)_c$ Quark States. Eur. Phys. J., C34: 435-437. Schumacher B, Bennett CH (2007). unpublished. See http://qpip-server.tcs.tifr.res.in qpip/HTML/Courses/Bennett/TIFR5.pdf,slides 39-47. Unruh WG (1976). Notes on Black Hole Evaporation. Phys. Rev. D, 14: 870.

Exploring the bulk of tidal charged micro-black holes

We study the bulk corresponding to tidal charged brane-world black holes. We employ a propagating algorithm which makes use of the three-dimensional multipole expansion and analytically yields the metric elements as functions of the five-dimensional coordinates and of the Adler-Deser-Misner mass, tidal charge, and brane tension. Since the projected brane equations cannot determine how the charge depends on the mass, our main purpose is to select the combinations of these parameters for which black holes of microscopic size possess a regular bulk. Our results could, in particular, be relevant for a better understanding of TeV-scale black holes.

Higgs production and decay from TeV scale black holes at the LHC

We perform detailed study of the Higgs production and decay, when Higgs is emitted from the black holes produced in proton-proton collisions at the Large Hadron Collider. We show that black hole production can significantly enhance the signal for the Higgs search at the LHC. We evaluate rapidity distribution of diphotons and transverse momentum distribution of bottom quarks, photons, tau leptons, top quarks and W bosons from Higgs decay, when Higgs is emitted from the black hole and also in case when these particles are produced directly from the black hole evaporation. We compare our results with the standard model backgrounds. We find that Higgs production from black holes is dominant over standard model production for $p_T^H > 100$ GeV, when $M_P=1$TeV. Diphotons from Higgs, when Higgs is produced from evaporation of black holes, are dominant over the standard model prediction, for diphoton rapidity $|y_{\gamma \gamma}| \leq 1$, while bottom quarks are dominant over QCD background for large bottom quark transverse momentum, $p_T^b > 300$ GeV, when $M_P=1$ TeV. We show that measurements of the photon and bottom quark transverse momentum distribution can provide valuable information about the value of the fundamental Planck scale. We also propose a new signal for black hole production at the LHC, an onset of increasing transverse momentum distribution of bottom quarks with large transverse momentum.

Astrophysical implications of hypothetical stable TeV-scale black holes

We analyze macroscopic effects of TeV-scale black holes, such as could possibly be produced at the LHC, in what is regarded as an extremely hypothetical scenario in which they are stable and, if trapped inside Earth, begin to accrete matter. We examine a wide variety of TeV-scale gravity scenarios, basing the resulting accretion models on first-principles, basic, and well-tested physical laws. These scenarios fall into two classes, depending on whether accretion could have any macroscopic effect on the Earth at times shorter than the Sun’s natural lifetime. We argue that cases with such an effect at shorter times than the solar lifetime are ruled out, since in these scenarios black holes produced by cosmic rays impinging on much denser white dwarfs and neutron stars would then catalyze their decay on time scales incompatible with their known lifetimes. We also comment on relevant lifetimes for astronomical objects that capture primordial black holes. In short, this study finds no basis for concerns that TeV-scale black holes from the LHC could pose a risk to Earth on time scales shorter than the Earth’s natural lifetime. Indeed, conservative arguments based on detailed calculations and the best-available scientific knowledge, including solid astronomical data, conclude, from multiple perspectives, that there is no risk of any significance whatsoever from such black holes.

Top production from black holes at the LHC

In theories with large extra dimension and with low quantum gravity scale near a TeV, it is expected that TeV-scale black holes to be produced in proton-proton collisions at the LHC with the center of mass energy of 14 TeV. Since the black holes temperature can be around 1 TeV, top quark production is expected from them via Hawking radiation. Within the Standard Model of particle physics top quarks are produced via strong interaction in $t\bar{t}$ pairs or via electroweak interaction singly. Therefore, black holes can be the new source of top quark production. In this article we present the total cross sections and transverse momentum distributions of top quark production from black holes at the LHC. We find that the top quarks from black holes tend to reside at very high transverse momentum region so it can be a very useful signature for the black holes at the LHC.

News about TeV-scale black holes

Collider produced black holes are the most exciting prediction from models with large extra dimensions. These black holes exist in an extreme region, in which gravity meets quantum field theory, particle physics, and thermodynamics. An investigation of the formation and decay processes can therefore provide us with important insights about the underlying theory and open a window to the understanding of Physics at the Planck scale. The production and the evaporation of TeV-scale black holes yields distinct signatures that have been examined closely during the last years, with analytical approaches as well as by use of numerical simulations. I present new results for the LHC, which take into account that, instead of a final decay, a black hole remnant can be left.

Higgs boson production from black holes at the CERN LHC

If the fundamental Planck scale is near a TeV, then TeV scale black holes should be produced in proton-proton collisions at the LHC where $\sqrt{s}=14\text{ }\text{ }\mathrm{TeV}$. As the temperature of the black holes can be $\ensuremath{\sim}1\text{ }\text{ }\mathrm{TeV}$ we also expect production of Higgs bosons from them via Hawking radiation. This is a different production mode for the Higgs boson, which would normally be produced via direct pQCD parton fusion processes. In this paper we compare total cross sections and transverse momentum distributions $d\ensuremath{\sigma}/d{p}_{T}$ for Higgs production from black holes at the LHC with those from direct parton fusion processes at next-to-next-to-leading order and next-to-leading order, respectively. We find that the Higgs production from black holes can be larger or smaller than the direct pQCD production depending upon the Planck mass and black hole mass. We also find that $d\ensuremath{\sigma}/d{p}_{T}$ of Higgs production from black holes increases as a function of ${p}_{T}$ which is in sharp contrast with the pQCD predictions where $d\ensuremath{\sigma}/d{p}_{T}$ decreases so we suggest that the measurement of an increase in $d\ensuremath{\sigma}/d{p}_{T}$ as ${p}_{T}$ increases for Higgs (or any other heavy particle) production can be a useful signature for black holes at the LHC.

TeV-scale black hole lifetimes in extra-dimensional Lovelock gravity**Work supported in part by the Department of Energy, contract DE-AC02-76SF00515.

We examine the mass loss rates and lifetimes of TeV-scale extra-dimensional black holes (BH) in Arkani-Hamed, Dimopoulos and Dvali-like models with Lovelock higher-curvature terms present in the action. In particular, we focus on the predicted differences between the canonical and microcanonical ensemble statistical mechanics descriptions of the Hawking radiation that result in the decay of these BH. In even numbers of extra dimensions, the employment of the microcanonical approach is shown to generally lead to a significant increase in the BH lifetime as in the case of the Einstein–Hilbert action. For odd numbers of extra dimensions, stable BH remnants occur when employing either description provided the highest order allowed Lovelock invariant is present. However, in this case, the time dependence of the mass loss rates obtained employing the two approaches will be different. These effects are in principle measurable at future colliders.

Simulations of black hole air showers in cosmic ray detectors

We present a comprehensive study of TeV black hole events in Earth's atmosphere originated by cosmic rays of very high energy. An advanced fortran Monte Carlo code is developed and used to simulate black hole extensive air showers from ultrahigh-energy neutrino-nucleon interactions. We investigate the characteristics of these events, compare the black hole air showers to standard model air showers, and test different theoretical and phenomenological models of black hole formation and evolution. The main features of black hole air showers are found to be independent of the model considered. No significant differences between models are likely to be observed at fluorescence telescopes and/or ground arrays. We also discuss the tau ``double-bang'' signature in black hole air showers. We find that the energy deposited in the second bang is too small to produce a detectable peak. Our results show that the theory of TeV-scale black holes in ultrahigh-energy cosmic rays leads to robust predictions, but the fine prints of new physics are hardly to be investigated through atmospheric black hole events in the near future.

Collider production of TeV scale black holes and higher-curvature gravity

We examine how the production of TeV scale black holes at colliders is influenced by the presence of Lovelock higher-curvature terms in the action of models with large extra dimensions. Such terms are expected to arise on rather general grounds, e.g., from string theory and are often used in the literature to model modifications to the Einstein-Hilbert action arising from quantum and/or stringy corrections. While adding the invariant which is quadratic in the curvature leads to quantitative modifications in black hole properties, cubic and higher invariants are found to produce significant qualitative changes, e.g., classically stable black holes. We use these higher-order curvature terms to construct a toy model of the black hole production cross section threshold. For reasonable parameter values we demonstrate that detailed measurements of the properties of black holes at future colliders will be highly sensitive to the presence of the Lovelock higher-order curvature terms.

New instability for rotating black branes and strings

The evolution of small perturbations around rotating black branes and strings, which are low energy solutions of string theory, are investigated. For simplicity, we concentrate on the Kerr solution times transverse flat extra dimensions, possibly compactified, but one can also treat other branes composed of any rotating black hole and extra transverse dimensions, as well as analogue black hole models and rotating bodies in fluid mechanics systems. It is shown that such a rotating black brane is unstable against any massless (scalar, vectorial, tensorial or other) field perturbation for a wide range of wavelengths and frequencies in the transverse dimensions. Since it holds for any massless field it can be considered, in this sense, a stronger instability than the one studied by Gregory and Laflamme. Accordingly, it has also a totally different physical origin. The perturbations can be stabilized if the extra dimensions are compactified to a length smaller than the minimum wavelength for which the instability settles in, resembling in this connection the Gregory–Laflamme case. Likewise, this instability will have no effect for astrophysical black holes. However, in the large extra dimensions scenario, where TeV scale black holes can be produced, this instability should be important. It seems plausible that the endpoint of this instability is a static, or very slowly rotating, black brane and some outgoing radiation at infinity.

Warped Phenomenology of Higher-Derivative Gravity

We examine the phenomenological implications at colliders for the existence of higher-derivative gravity terms as extensions to the Randall-Sundrum model. Such terms are expected to arise on rather general grounds, e.g., from string theory. In 5-d, if we demand that the theory be unitary and ghost free, these new contributions to the bulk action are uniquely of the Gauss-Bonnet form. We demonstrate that the usual expectations for the production cross section and detailed properties of graviton Kaluza-Klein resonances and TeV-scale black holes can be substantially altered by existence of these additional contributions. It is shown that measurements at future colliders will be highly sensitive to the presence of such terms.

Supersymmetry production from a TeV scale black hole at CERN LHC

If the fundamental Planck scale is near a TeV, then we should expect to see TeV scale black holes at the CERN LHC. Similarly, if the scale of supersymmetry (SUSY) breaking is sufficiently low, then we might expect to see light supersymmetric particles in the next generation of colliders. If the mass of the supersymmetric particle is of order a TeV and is comparable to the temperature of a typical TeV scale black hole, then such sparticles will be copiously produced via Hawking radiation: The black hole will act as a resonance for sparticles, among other things. In this paper we compare various signatures for SUSY production at LHC, and we contrast the situation where the sparticles are produced directly via parton fusion processes with the situation where they are produced indirectly through black hole resonances. We found that black hole resonances provide a larger source for heavy mass SUSY (squark and gluino) production than the direct perturbative QCD-SUSY production via parton fusion processes depending on the values of the Planck mass and black hole mass. Hence black hole production at LHC may indirectly act as a dominant channel for SUSY production. We also found that the differential cross sectionmore » d{sigma}/dp{sub t} for SUSY production increases as a function of the p{sub t} (up to p{sub t} equal to about 1 TeV or more) of the SUSY particles (squarks and gluinos), which is in sharp contrast with the pQCD predictions where the differential cross section d{sigma}/dp{sub t} decreases as p{sub t} increases for high p{sub t} about 1 TeV or higher. This is a feature for any particle emission from a TeV scale black hole as long as the temperature of the black hole is very high ({approx}TeV). Hence the measurement of increase of d{sigma}/dp{sub t} with p{sub t} for p{sub t} up to about 1 TeV or higher for final state particles might be a useful signature for black hole production at LHC.« less

How classical are TeV-scale black holes?

We show that the Hawking temperature and the entropy of black holes are subject to corrections from two sources: the generalized uncertainty principle and thermal fluctuations. Both effects increase the temperature and decrease the entropy, resulting in faster decay and ‘less classical’ black holes. We discuss the implications of these results for TeV-scale black holes that are expected to be produced at future colliders.