This is an automated list of black hole papers, thanks to the arxiv api. (Black holes, hands down, is my favorite cosmic topic.)
I confess that automation is my way of embracing a bit of laziness. When I finish a book I'm left with the dilemma of what to read next, this would then be a great way to face this issue.
pip install arxiv
The list of papers is available in this README.md
But you could access it from this website
Title | Author(s) | Date | Abstract |
---|---|---|---|
Exact Black String Solutions in Three Dimensions | James H. Horne, Gary T. Horowitz | 1991-08-14 | A family of exact conformal field theories is constructed which describe charged black strings in three dimensions. Unlike previous charged black hole or extended black hole solutions in string theory, the low energy spacetime metric has a regular inner horizon (in addition to the event horizon) and a timelike singularity. As the charge to mass ratio approaches unity, the event horizon remains but the singularity disappears. |
String Winding in a Black Hole Geometry | Mordechai Spiegelglas | 1991-08-21 |
|
On the Perturbations of String-Theoretic Black Holes | Gerald Gilbert | 1991-08-22 | The perturbations of string-theoretic black holes are analyzed by generalizing the method of Chandrasekhar. Attention is focussed on the case of the recently considered charged string-theoretic black hole solutions as a representative example. It is shown that string-intrinsic effects greatly alter the perturbed motions of the string-theoretic black holes as compared to the perturbed motions of black hole solutions of the field equations of general relativity, the consequences of which bear on the questions of the scattering behavior and the stability of string-theoretic black holes. The explicit forms of the axial potential barriers surrounding the string-theoretic black hole are derived. It is demonstrated that one of these, for sufficiently negative values of the asymptotic value of the dilaton field, will inevitably become negative in turn, in marked contrast to the potentials surrounding the static black holes of general relativity. Such potentials may in principle be used in some cases to obtain approximate constraints on the value of the string coupling constant. The application of the perturbation analysis to the case of two-dimensional string-theoretic black holes is discussed. |
Superstring Compactification and Target Space Duality | John H. Schwarz | 1991-08-26 | This review talk focusses on some of the interesting developments in the area of superstring compactification that have occurred in the last couple of years. These include the discovery that mirror symmetric" pairs of Calabi--Yau spaces, with completely distinct geometries and topologies, correspond to a single (2,2) conformal field theory. Also, the concept of target-space duality, originally discovered for toroidal compactification, is being extended to Calabi--Yau spaces. It also associates sets of geometrically distinct manifolds to a single conformal field theory. A couple of other topics are presented very briefly. One concerns conceptual challenges in reconciling gravity and quantum mechanics. It is suggested that certain distasteful allegations" associated with quantum gravity such as loss of quantum coherence, unpredictability of fundamental parameters of particle physics, and paradoxical features of black holes are likely to be circumvented by string theory. Finally there is a brief discussion of the importance of supersymmetry at the TeV scale, both from a practical point of view and as a potentially significant prediction of string theory. |
Superstring in Two Dimensional Black Hole | Shin'ichi Nojiri | 1991-08-29 | We construct superstring theory in two dimensional black hole background based on supersymmetric |
Effective Superstrings | Zhu Yang | 1991-09-05 | We generalize the method of quantizing effective strings proposed by Polchinski and Strominger to superstrings. The Ramond-Neveu-Schwarz string is different from the Green-Schwarz string in non-critical dimensions. Both are anomaly-free and Poincare invariant. Some implications of the results are discussed. The formal analogy with 4D (super)gravity is pointed out. |
Some Applications of String Field Theory | Ashoke Sen | 1991-09-12 | We study general properties of the classical solutions in non-polynomial closed string field theory and their relationship with two dimensional conformal field theories. In particular we discuss how different conformal field theories which are related by marginal or nearly marginal deformations can be regarded as different classical solutions of some underlying string field theory. We also discuss construction of a classical solution labelled by infinite number of parameters in string field theory in two dimensions. For a specific set of values of the parameters the solution can be identified to the black hole solution. |
String Effective Action and Two Dimensional Charged Black Hole | S. Pratik Khastgir, Alok Kumar | 1991-09-14 | Graviton-dilaton background field equations in three space-time dimensions, following from the string effective action are solved when the metric has only time dependence. By taking one of the two space dimensions as compact, our solution reproduces a recently discovered charged black hole solution in two space-time dimensions. Solutions in presence of nonvanishing three dimensional background antisymmetric tensor field are also discussed. |
On the connection between Quantum Mechanics and the geometry of two-dimensional strings | J. Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1991-09-17 | On the basis of an area-preserving symmetry in the phase space of a one-dimensional matrix model - believed to describe two-dimensional string theory in a black-hole background which also allows for space-time foam - we give a geometric interpretation of the fact that two-dimensional stringy black holes are consistent with conventional quantum mechanics due to the infinite gauged `W-hair' property that characterises them. |
Beyond the Large N Limit: Non-linear W(infinity) as symmetry of the SL(2,R)/U(1) coset model | I. Bakas, E. Kiritsis | 1991-09-18 | We show that the symmetry algebra of the $SL(2,R){k}/U(1)$ coset model is a non-linear deformation of $W{\infty}$, characterized by |
Elements of String Cosmology | A. A. Tseytlin, C. Vafa | 1991-09-25 | Aspects of string cosmology for critical and non-critical strings are discussed emphasizing the necessity to account for the dilaton dynamics for a proper incorporation of ``large - small" duality. This drastically modifies the intuition one has with Einstein's gravity. For example winding modes, even though contribute to energy density, oppose expansion and if not annihilated will stop the expansion. Moreover we find that the radiation dominated era of the standard cosmology emerges quite naturally in string cosmology. Our analysis of non-critical string cosmology provides a reinterpretation of the (universal cover of the) recently studied two dimensional black hole solution as a conformal realization of cosmological solutions found previously by Mueller. |
Manifestly $O(d,d)$ Invariant Approach to Space-Time Dependent String Vacua | K. A. Meissner, G. Veneziano | 1991-10-01 | An |
Open String Theory in 1+1 Dimensions | M. Bershadsky, D. Kutasov | 1991-10-14 | We show that tree level open two dimensional string theory is exactly solvable; the solution exhibits some unusual features, and is qualitatively different from the closed case. The open string tachyon'' S -- matrix describes free fermions, which can be interpreted as the quarks at the ends of the string. These quarks'' live naturally on a lattice in space-time. We also find an exact vacuum solution of the theory, corresponding to a charged black hole. |
Superspace WZW Models and Black Holes | Changhyun Ahn, Martin Rocek, Kareljan Schoutens, Alexander Sevrin | 1991-10-14 | We show how to write an off-shell action for the |
(Super-) String in Two Dimensional Black Hole and Target Space Dualities | Shin'ichi Nojiri | 1991-10-17 | We review the recently proposed string theory in two dimensional black hole background. Especially, the structure of the duality in the target space is discussed. The duality is analogous to \lq\lq |
Generalized Duality and Singular Strings in Higher Dimensions | I. Bars, K. Sfetsos | 1991-10-18 | Deformations of gauged WZW actions are constructed for any pair |
Some Exact Solutions of String Theory in Four and Five Dimensions | Petr Horava | 1991-10-24 | We find several classes of exact classical solutions of critical bosonic string theory, constructed as twisted products of one Euclidean and one Minkowskian 2D black hole coset. One class of these solutions leads (after tensoring with free scalars and supersymmetrizing) to a rotating version of the recently discovered exact black fivebrane. Another class represents a one-parameter family of axisymmetric stationary four-dimensional targets with horizons. Global properties and target duality of the 4D solutions are briefly analyzed. |
Non-Compact WZW Conformal Field Theories | Krzysztof Gawedzki | 1991-10-31 | We discuss non-compact WZW sigma models, especially the ones with symmetric space |
Topological Field Theories and Space-Time Singularity | Tohru Eguchi | 1991-11-01 | Based on a study of recently proposed solution of 2 dim. black hole we argue that the space-time singularities of general relativity may be described by topological field theories (TFTs). We also argue that in general TFT is a field theory which decsribes singular configurations with a reduced holonomy in its field space. |
On the Evaporation of Black Holes in String Theory | J. Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1991-11-18 | We show that, in string theory, the quantum evaporation and decay of black holes in two-dimensional target space is related to imaginary parts in higher-genus string amplitudes. These arise from the regularisation of modular infinities due to the sum over world-sheet configurations, that are known to express the instabilities of massive string states in general, and are not thermal in character. The absence of such imaginary parts in the matrix model limit confirms that the latter constitutes the final stage of the evaporation process, at least in perturbation theory. Our arguments appear to be quite generic, related only to the summation over world-sheet surfaces, and hence should also apply to higher-dimensional target spaces. |
Charged Black Holes in Two-Dimensional String Theory | Michael D. McGuigan, Chiara R. Nappi, Scott A. Yost | 1991-11-20 | We discuss two dimensional string theories containing gauge fields introduced either via coupling to open strings, in which case we get a Born-Infeld type action, or via heterotic compactification. The solutions to the modified background field equations are charged black holes which exhibit interesting space-time geometries. We also compute their masses and charges. |
Instabilities in the gravitational background and string theory | Anirvan M. Sengupta | 1991-11-21 | We indicate the tentative source of instability in the two-dimensional black hole background. There are relevant operators among the tachyon and the higher level vertex operators in the conformal field theory. Connection of this instability with Hawking radiation is not obvious. The situation is somewhat analogous to fields in the background of a negative mass Euclidean Schwarzschild solution (in four dimensions). Speculation is made about decay of the Minkowski black hole into finite temperature flat space. |
"the Instability of String-Theoretic Black Holes" | Gerald Gilbert | 1991-11-21 | It is demonstrated that static, charged, spherically--symmetric black holes in string theory are classically and catastrophically unstable to linearized perturbations in four dimensions, and moreover that unstable modes appear for arbitrarily small positive values of the charge. This catastrophic classical instability dominates and is distinct from much smaller and less significant effects such as possible quantum mechanical evaporation. The classical instability of the string--theoretic black hole contrasts sharply with the situation which obtains for the Reissner--Nordstr"om black hole of general relativity, which has been shown by Chandrasekhar to be perfectly stable to linearized perturbations at the event horizon. |
Modified Black Holes in Two Dimensional Gravity | N. Mohammedi | 1991-11-22 | The |
A Classical Instability of Reissner-Nordstrom Solutions and the Fate of Magnetically Charged Black Holes | K. Lee, V. P. Nair, E. J. Weinberg | 1991-11-22 | Working in the context of spontaneously broken gauge theories, we show that the magnetically charged Reissner-Nordstrom solution develops a classical instability if the horizon is sufficiently small. This instability has significant implications for the evolution of a magnetically charged black hole. In particular, it leads to the possibility that such a hole could evaporate completely, leaving in its place a nonsingular magnetic monopole. |
On Black Holes In String Theory | Edward Witten | 1991-11-25 | In these lecture notes from Strings `91, I briefly sketch the analogy between two dimensional black holes and the s-wave sector of four dimensional black holes, and the physical interest of the latter, particularly in the magnetically charged case. |
Evanescent Black Holes | C. Callan, S. Giddings, J. Harvey, A. Strominger | 1991-11-28 | A renormalizable theory of quantum gravity coupled to a dilaton and conformal matter in two space-time dimensions is analyzed. The theory is shown to be exactly solvable classically. Included among the exact classical solutions are configurations describing the formation of a black hole by collapsing matter. The problem of Hawking radiation and backreaction of the metric is analyzed to leading order in a |
Perturbations of a Stringy Black Hole | E. Raiten | 1991-12-02 | We extend the three dimensional stringy black hole of Horne and Horowitz to four dimensions. After a brief discussion of the global properties of the metric, we discuss the stability of the background with respect to small perturbations, following the methods of Gilbert and of Chandrasekhar. The potential for axial perturbations is found to be positive definite. |
Black Holes in Magnetic Monopoles | K. Lee, V. P. Nair, Erick J. Weinberg | 1991-12-04 | We study magnetically charged classical solutions of a spontaneously broken gauge theory interacting with gravity. We show that nonsingular monopole solutions exist only if the Higgs vacuum expectation value |
Nonlinear $\hat{W}_{\infty}$ Current Algebra in the SL(2,R)/U(1) Coset Model | Feng Yu, Yong-Shi Wu | 1991-12-04 | Previously we have established that the second Hamiltonian structure of the KP hierarchy is a nonlinear deformation, called $\hat{W}{\infty}$, of the linear, centerless $W{\infty}$ algebra. In this letter we present a free-field realization for all generators of $\hat{W}{\infty}$ in terms of two scalars as well as an elegant generating function for the $\hat{W}{\infty}$ currents in the classical conformal |
Quantum Mechanics and Black Holes in Four-Dimensional String Theory | J. Ellis, N. Mavromatos, D. Nanopoulos | 1991-12-20 | In previous papers we have shown how strings in a two-dimensional target space reconcile quantum mechanics with general relativity, thanks to an infinite set of conserved quantum numbers, ``W-hair'', associated with topological soliton-like states. In this paper we extend these arguments to four dimensions, by considering explicitly the case of string black holes with radial symmetry. The key infinite-dimensional W-symmetry is associated with the |
Euclidean Black Hole Vortices | Fay Dowker, Ruth Gregory, Jennie Traschen | 1991-12-20 | We argue the existence of solutions of the Euclidean Einstein equations that correspond to a vortex sitting at the horizon of a black hole. We find the asymptotic behaviours, at the horizon and at infinity, of vortex solutions for the gauge and scalar fields in an abelian Higgs model on a Euclidean Schwarzschild background and interpolate between them by integrating the equations numerically. Calculating the backreaction shows that the effect of the vortex is to cut a slice out of the Euclidean Schwarzschild geometry. Consequences of these solutions for black hole thermodynamics are discussed. |
Generalized Duality in Curved String-Backgrounds | Amit Giveon, Martin Rocek | 1991-12-23 | The elements of |
Factorizations of natural embeddings of l_p^n int L_r | Tadek Figiel, William B. Johnson, Gideon Schechtman | 1992-01-06 | This is a continuation of the paper [FJS] with a similar title. Several results from there are strengthened, in particular: 1. If T is a "natural" embedding of l_2^n into L_1 then, for any well-bounded factorization of T through an L_1 space in the form T=uv with v of norm one, u well-preserves a copy of l_1^k with k exponential in n. 2. Any norm one operator from a C(K) space which well-preserves a copy of l_2^n also well-preserves a copy of l_{\infty}^k with k exponential in n. As an application of these and other results we show the existence, for any n, of an n-dimensional space which well-embeds into a space with an unconditional basis only if the latter contains a copy of l_{\infty}^k with k exponential in n. |
An Algorithm to Generate Classical Solutions for String Effective Action | S. Kar, S. Khastgir, A. Kumar | 1992-01-07 | It is shown explicitly, that a number of solutions for the background field equations of the string effective action in space-time dimension D can be generated from any known lower dimensional solution, when background fields have only time dependence. An application of the result to the two dimensional charged black hole is presented. The case of background with more general coordinate dependence is also discussed. |
A Note on Background (In)dependence | Nathan Seiberg, Stephen Shenker | 1992-01-09 | In general quantum systems there are two kinds of spacetime modes, those that fluctuate and those that do not. Fluctuating modes have normalizable wavefunctions. In the context of 2D gravity and ``non-critical'' string theory these are called macroscopic states. The theory is independent of the initial Euclidean background values of these modes. Non-fluctuating modes have non-normalizable wavefunctions and correspond to microscopic states. The theory depends on the background value of these non-fluctuating modes, at least to all orders in perturbation theory. They are superselection parameters and should not be minimized over. Such superselection parameters are well known in field theory. Examples in string theory include the couplings |
Scalar-Tensor Quantum Gravity in Two Dimensions | J. Russo, A. A. Tseytlin | 1992-01-12 | We discuss some classical and quantum properties of 2d gravity models involving metric and a scalar field. Different models are parametrized in terms of a scalar potential. We show that a general Liouville-type model with exponential potential and linear curvature coupling is renormalisable at the quantum level while a particular model (corresponding to D=2 graviton-dilaton string effective action and having a black hole solution) is finite. We use the condition of a split" Weyl symmetry to suggest possible expressions for the effective" action which includes the quantum anomaly term. |
Supersymmetric Black Holes | Renata Kallosh | 1992-01-15 | The effective action of |
Exact Bosonic and Supersymmetric String Black Hole Solutions | I. Jack, D. R. T. Jones, J. Panvel | 1992-01-21 | We show that Witten's two-dimensional string black hole metric is exactly conformally invariant in the supersymmetric case. We also demonstrate that this metric, together with a recently proposed exact metric for the bosonic case, are respectively consistent with the supersymmetric and bosonic |
Quantum Hair on Black Holes | Sidney Coleman, John Preskill, Frank Wilczek | 1992-01-28 | A black hole may carry quantum numbers that are {\it not} associated with massless gauge fields, contrary to the spirit of the ``no-hair'' theorems. We describe in detail two different types of black hole hair that decay exponentially at long range. The first type is associated with discrete gauge charge and the screening is due to the Higgs mechanism. The second type is associated with color magnetic charge, and the screening is due to color confinement. In both cases, we perform semi-classical calculations of the effect of the hair on local observables outside the horizon, and on black hole thermodynamics. These effects are generated by virtual cosmic strings, or virtual electric flux tubes, that sweep around the event horizon. The effects of discrete gauge charge are non-perturbative in |
Are Horned Particles the Climax of Hawking Evaporation? | T. Banks, A. Dabolkhar, M. R. Douglas, M. O' Loughlin | 1992-01-28 | We investigate the proposal by Callan, Giddings, Harvey and Strominger (CGHS) that two dimensional quantum fluctuations can eliminate the singularities and horizons formed by matter collapsing on the nonsingular extremal black hole of dilaton gravity. We argue that this scenario could in principle resolve all of the paradoxes connected with Hawking evaporation of black holes. However, we show that the generic solution of the model of CGHS is singular. We propose modifications of their model which may allow the scenario to be realized in a consistent manner. |
On the Black-Hole Conformal Field Theory Coupled to the Polyakov's String Theory. A Non Perturbative Analysis | M. Martellini, M. Spreafico, K. Yoshida | 1992-01-29 | We couple the 2D black-hole conformal field theory discovered by Witten to a |
Black Hole Evaporation in 1+1 Dimensions | J. Russo, L. Susskind, L. Thorlacius | 1992-01-29 | The formation and quantum mechanical evaporation of black holes in two spacetime dimensions can be studied using effective classical field equations, recently introduced by Callan {\it et al.} We find that gravitational collapse always leads to a curvature singularity, according to these equations, and that the region where the quantum corrections introduced by Callan {\it et al.} could be expected to dominate is on the unphysical side of the singularity. The model can be successfully applied to study the back-reaction of Hawking radiation on the geometry of large mass black holes, but the description breaks down before the evaporation is complete. |
Dynamics of Extremal Black Holes | S. B. Giddings, A. Strominger | 1992-02-03 | Particle scattering and radiation by a magnetically charged, dilatonic black hole is investigated near the extremal limit at which the mass is a constant times the charge. Near this limit a neighborhood of the horizon of the black hole is closely approximated by a trivial product of a two-dimensional black hole with a sphere. This is shown to imply that the scattering of long-wavelength particles can be described by a (previously analyzed) two-dimensional effective field theory, and is related to the formation/evaporation of two-dimensional black holes. The scattering proceeds via particle capture followed by Hawking re-emission, and naively appears to violate unitarity. However this conclusion can be altered when the effects of backreaction are included. Particle-hole scattering is discussed in the light of a recent analysis of the two-dimensional backreaction problem. It is argued that the quantum mechanical possibility of scattering off of extremal black holes implies the potential existence of additional quantum numbers - referred to as ``quantum whiskers'' - characterizing the black hole. |
Exact Solutions of Four Dimensional Black Holes in String Theory | David Gershon | 1992-02-03 | We construct an exact CFT as an SL(2,R)xSU(2)/U(1)^2 gauged WZW model, which describes a black hole in 4 dimensions. Another exact solution, describing a black membrane in 4D (in the sense that the event horizon is an infinite plane) is found as an SL(2,R)xU(1)^2/U(1) gauged WZW model. Finally, we construct an exact solution of a 4D black hole with electromagnetic field, as an SL(2,R)xSU(2)xU(1)/U(1)^2 gauged WZW model. This black hole carries both electric and axionic charges. |
Black Holes as Elementary Particles | C. F. E. Holzhey, F. Wilczek | 1992-02-05 | It is argued that the qualitative features of black holes, regarded as quantum mechanical objects, depend both on the parameters of the hole and on the microscopic theory in which it is embedded. A thermal description is inadequate for extremal holes. In particular, extreme holes of the charged dilaton family can have zero entropy but non-zero, and even (for |
[Spinning Braid Group Representation and the Fractional Quantum Hall | |||
Effect](http://arxiv.org/abs/hep-th/9202024v1) | Christopher Ting, C. H. Lai | 1992-02-07 | The path integral approach to representing braid group is generalized for particles with spin. Introducing the notion of {\em charged} winding number in the super-plane, we represent the braid group generators as homotopically constrained Feynman kernels. In this framework, super Knizhnik-Zamolodchikov operators appear naturally in the Hamiltonian, suggesting the possibility of {\em spinning nonabelian} anyons. We then apply our formulation to the study of fractional quantum Hall effect (FQHE). A systematic discussion of the ground states and their quasi-hole excitations is given. We obtain Laughlin, Halperin and Moore-Read states as {\em exact} ground state solutions to the respective Hamiltonians associated to the braid group representations. The energy gap of the quasi-excitation is also obtainable from this approach. |
Black Holes in Higher Derivative Gravity Theories | S. Mignemi, D. L. Wiltshire | 1992-02-08 | We study static spherically symmetric solutions of Einstein gravity plus an action polynomial in the Ricci scalar, |
[Splitting of an Extremal Reissner-Nordström Throat via Quantum | |||
Tunneling](http://arxiv.org/abs/hep-th/9202037v2) | Dieter R. Brill | 1992-02-12 | The interior near the horizon of an extremal Reissner-Nordstr"om black hole is taken as an initial state for quantum mechanical tunneling. An instanton is presented that connects this state with a final state describing the presence of several horizons. This is interpreted as a WKB description of fluctuations due to the throat splitting into several components. |
An Alternative Scenario for Non-Abelian Quantum Hair | Amitabha Lahiri | 1992-02-13 | Topologically charged black holes in a theory with a 2-form coupled to a non-abelian gauge field are investigated. It is found that the classification of the ground states is similar to that in the theory of non-abelian discrete quantum hair. |
Properties of Asymptotically Flat Two-Dimensional Black Holes | R. B. Mann, M. S. Morris, S. F. Ross | 1992-02-19 | We investigate properties of two-dimensional asymptotically flat black holes which arise in both string theory and in scale invariant theories of gravity. By introducing matter sources in the field equations we show how such objects can arise as the endpoint of gravitational collapse. We examine the motion of test particles outside the horizons, and show that they fall through in a finite amount of proper time and an infinite amount of coordinate time. We also investigate the thermodynamic and quantum properties, which give rise to a fundamental length scale. The 't Hooft prescription for cutting off eigenmodes of particle wave functions is shown to be source dependent, unlike the four-dimensional case. The relationship between these black holes and those considered previously in |
S-Wave Scattering of Charged Fermions by a Magnetic Black Hole | Mark Alford, Andrew Strominger | 1992-02-21 | We argue that, classically, |
A Possible Black Hole Background in c=1 Matrix Model | Zhu Yang | 1992-02-22 | We propose a new space-time interpretation for c=1 matrix model with potential |
Strings on Curved Spacetimes: Black Holes, Torsion, and Duality | Paul Ginsparg, Fernando Quevedo | 1992-02-29 | We present a general discussion of strings propagating on noncompact coset spaces |
Measuring the $W$-hair of String Black Holes | John Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1992-03-05 | We have argued previously that the infinitely many gauge symmetries of string theory provide an infinite set of conserved (gauge) quantum numbers ( |
[Supersymmetric, cold and lukewarm black holes in cosmological | |||
Einstein-Maxwell theory](http://arxiv.org/abs/hep-th/9203018v1) | L. J. Romans | 1992-03-08 | In flat space, the extreme Reissner-Nordstr\o m (RN) black hole is distinguished by its coldness (vanishing Hawking temperature) and its supersymmetry. We examine RN solutions to Einstein-Maxwell theory with a cosmological constant |
Two Dimensional Stringy Black Holes with One Asymptotically Flat Domain | Petr Horava | 1992-03-11 | The exact black hole solution of 2D closed string theory has, as any other maximally extended Schwarzschild-like geometry, two asymptotically flat spacetime domains. One can get rid of the second domain by gauging the discrete symmetry on the SL(2,R)/U(1) coset that interchanges the two asymptotic domains and preserves the Kruskal time orientation everywhere in the Kruskal plane. Here it is shown that upon performing this orbifold procedure, we obtain a theory of unoriented open and closed strings in a black hole background, with just one asymptotically flat domain and a time-like orbifold singularity at the origin. All of the open string states of the model are confined to the orbifold singularity. We also discuss various physical aspects of the truncated black hole, in particular its target duality -- the model is dual to a conventional open string theory in the black hole geometry. |
Black Holes from Non-Abelian Toda Theories | Jean-Loup Gervais, Mikhail V. Saveliev | 1992-03-17 | NON-ABELIAN TODA THEORIES are shown to provide EXACTLY SOLVABLE conformal systems in the presence of a BLACK HOLE which may be regarded as describing a string propagating in target space with a black-hole metric. These theories are associated with non-canonical |
The Causal Structure of Two-Dimensional Spacetimes | Dan Christensen, Robert B. Mann | 1992-03-18 | We investigate the causal structure of |
Evaporation of Two Dimensional Black Holes | S. W. Hawking | 1992-03-18 | Callan, Giddings, Harvey and Strominger have proposed an interesting two dimensional model theory that allows one to consider black hole evaporation in the semi-classical approximation. They originally hoped the black hole would evaporate completely without a singularity. However, it has been shown that the semi-classical equations will give a singularity where the dilaton field reaches a certain critical value. Initially, it seems this singularity will be hidden inside a black hole. However, as the evaporation proceeds, the dilaton field on the horizon will approach the critical value but the temperature and rate of emission will remain finite. These results indicate either that there is a naked singularity, or (more likely) that the semi-classical approximation breaks down when the dilaton field approaches the critical value. |
Hawking Radiation and Back-Reaction | L. Susskind, L. Thorlacius | 1992-03-20 | The puzzles of black hole evaporation can be studied in the simplified context of 1+1 dimensional gravity. The semi-classical equations of Callan, Giddings, Harvey and Strominger provide a consistent description of the evaporation process which we describe in detail. We consider the possibility that black hole evolution leads to massive stable remnants. We show that such zero temperature remnant solutions exist but we also prove that a decaying black hole cannot evolve into one of them. Finally we consider the issue of loss of quantum information behind the global event horizon which develops in these geometries. An analogy with a well known solvable system shows that there may be less to information than meets the eye. |
Black Holes and Massive Remnants | S. B. Giddings | 1992-03-21 | This paper revisits the conundrum faced when one attempts to understand the dynamics of black hole formation and evaporation without abandoning unitary evolution. Previous efforts to resolve this puzzle assume that information escapes in corrections to the Hawking process, that an arbitrarily large amount of information is transmitted by a planckian energy or contained in a Planck-sized remnant, or that the information is lost to another universe. Each of these possibilities has serious difficulties. This paper considers another alternative: remnants that carry large amounts of information and whose size and mass depend on their information content. The existence of such objects is suggested by attempts to incorporate a Planck scale cutoff into physics. They would greatly alter the late stages of the evaporation process. The main drawback of this scenario is apparent acausal behavior behind the horizon. |
Target Space Structure of a Chiral Gauged Wess-Zumino-Witten Model | Supriya K. Kar, Alok Kumar | 1992-03-27 | The background for string propagation is obtained by a chiral gauging of the |
Rotating Dilaton Black Holes | James H. Horne, Gary T. Horowitz | 1992-03-30 | It is shown that an arbitrarily small amount of angular momentum can qualitatively change the properties of extremal charged black holes coupled to a dilaton. In addition, the gyromagnetic ratio of these black holes is computed and an exact rotating black string solution is presented. |
Noncompact Coset Spaces in String Theory | Fernando Quevedo | 1992-04-03 | A brief overview of strings propagating on noncompact coset spaces G/H is presented in terms of WZW models. The role played by isometries in the existence of target space duality and by fixed points of the gauge transformations in the existence of singularities and horizons, is emphasized. A general classification of the spaces with a single time-like coordinate is presented. The spacetime geometry of a class of models, existing for every dimension and having cosmological and black hole-like interpretations, is discussed. |
Dilaton Gravity and No-Hair Theorem in Two Dimensions | Olaf Lechtenfeld, Chiara Nappi | 1992-04-10 | We study a general class of two-dimensional theories of the dilaton-gravity type inspired by string theory and show that they admit charged multiple-horizon black holes. These solutions are proved to satisfy scalar no-hair theorems. |
Quantum Fermion Hair | Ruth Gregory, Jeffrey Harvey | 1992-04-10 | It is shown that the Dirac operator in the background of a magnetic %Reissner-Nordstr"om black hole and a Euclidean vortex possesses normalizable zero modes in theories containing superconducting cosmic strings. One consequence of these zero modes is the presence of a fermion condensate around magnetically charged black holes which violates global quantum numbers. |
Gamma-Ray Bursts as the Death Throes of Massive Binary Stars | Ramesh Narayan, Bohdan Paczyński, Tsvi Piran | 1992-04-13 | It is proposed that gamma-ray bursts are created in the mergers of double neutron star binaries and black hole neutron star binaries at cosmological distances. Bursts with complex profiles and relatively long durations are the result of magnetic flares generated by the Parker instability in a post-merger differentially-rotating disk. Some bursts may also be produced through neutrino-antineutrino annihilation into electrons and positrons. In both cases, an optically thick fireball of size |
On the Stability of a Stringy Black Hole | A. Carlini, F. Fucito, M. Martellini | 1992-04-13 | We study the stability under perturbations of a charged four dimensional stringy black hole arising from gauging a previously studied WZW model. We find that the black hole is stable only in the extremal case |
Asymptotic Behavior of 2-d Black Holes | E. Raiten | 1992-04-15 | We consider the solutions of the field equations for the large |
Rotating Charged Black Hole Solution in Heterotic String Theory | Ashoke Sen | 1992-04-15 | We construct a solution of the classical equations of motion arising in the low energy effective field theory for heterotic string theory. This solution describes a black hole in four dimensions carrying mass |
Hawking radiation: a particle physics perspective | Matt Visser | 1992-04-20 | It has recently become fashionable to regard black holes as elementary particles. By taking this suggestion seriously it is possible to cobble together an elementary particle physics based estimate for the decay rate |
Quantum Emission from Two-Dimensional Black Holes | Steven B. Giddings, W. M. Nelson | 1992-04-22 | We investigate Hawking radiation from two-dimensional dilatonic black holes using standard quantization techniques. In the background of a collapsing black hole solution the Bogoliubov coefficients can be exactly determined. In the regime after the black hole has settled down to an `equilibrium' state but before the backreaction becomes important these give the known result of a thermal distribution of Hawking radiation at temperature lambda/(2pi). The density matrix is computed in this regime and shown to be purely thermal. Similar techniques can be used to derive the stress tensor. The resulting expression agrees with the derivation based on the conformal anomaly and can be used to incorporate the backreaction. Corrections to the thermal density matrix are also examined, and it is argued that to leading order in perturbation theory the effect of the backreaction is to modify the Bogoliubov transformation, but not in a way that restores information lost to the black holes. |
The Physics of 2-d Stringy Spacetimes | Gary W. Gibbons, Malcolm J. Perry | 1992-04-28 | We examine the two-dimensional spacetimes that emerge from string theory. We find all the solutions with no tachyons, and show that the only non-trivial solution is the black hole spacetime. We examine the role of duality in this picture. We then explore the thermodynamics of these solutions which is complicated by the fact that only in two spacetime dimensions is it impossible to redefine the dilaton field in terms of a canonical scalar field. Finally, we extend our analysis to the heterotic string, and briefly comment on exact, as opposed to perturbative, solutions. |
On the W-hair of String Black Holes and the Singularity Problem | John Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1992-04-29 | We argue that the infinitely many gauge symmetries of string theory provide an infinite set of conserved (gauge) quantum numbers (W-hair) which characterise black hole states and maintain quantum coherence, even during exotic processes like black hole evaporation/decay. We study ways of measuring the W-hair of spherically-symmetric four-dimensional objects with event horizons, treated as effectively two-dimensional string black holes. Measurements can be done either through the s-wave scattering of light particles off the string black-hole background, or through interference experiments of Aharonov-Bohm type. We also speculate on the role of the extended W-symmetries possessed by the topological field theories that describe the region of space-time around a singularity. |
The Black Hole in Three Dimensional Space Time | Máximo Bañados, Claudio Teitelboim, Jorge Zanelli | 1992-04-29 | The standard Einstein-Maxwell equations in 2+1 spacetime dimensions, with a negative cosmological constant, admit a black hole solution. The 2+1 black hole -characterized by mass, angular momentum and charge, defined by flux integrals at infinity- is quite similar to its 3+1 counterpart. Anti-de Sitter space appears as a negative energy state separated by a mass gap from the continuous black hole spectrum. Evaluation of the partition function yields that the entropy is equal to twice the perimeter length of the horizon. |
Statistical Mechanics of Black Holes | B. Harms, Y. Leblanc | 1992-05-11 | We analyze the statistical mechanics of a gas of neutral and charged black holes. The microcanonical ensemble is the only possible approach to this system, and the equilibrium configuration is the one for which most of the energy is carried by a single black hole. Schwarzschild black holes are found to obey the statistical bootstrap condition. In all cases, the microcanonical temperature is identical to the Hawking temperature of the most massive black hole in the gas. U(1) charges in general break the bootstrap property. The problems of black hole decay and of quantum coherence are also addressed. |
Stability Analysis of a Stringy Black Hole | Rue-Ron Hsu, Green Huang, Wei-Fu Lin, Chin-Rong Lee | 1992-05-12 | We investigate the stability of charged black holes in two-dimensional heterotic string theories that were recently discussed by McGuidan, Nappi and Yost. In the framework of small time-dependent perturbation, we find that these black holes are linearly stable. |
Supersymmetry as a Cosmic Censor | Renata Kallosh, Andrei Linde, Tomás OrtĂn, Amanda Peet, Antoine Van Proeyen | 1992-05-13 | In supersymmetric theories the mass of any state is bounded below by the values of some of its charges. The corresponding bounds in case of Schwarzschild and Reissner-Nordstr"om black holes are known to coincide with the requirement that naked singularities be absent. Here we investigate charged dilaton black holes in this context. We show that the extreme solutions saturate the supersymmetry bound of |
Fadeev-Popov Ghosts and 1+1 Dimensional Black Hole Evaporation | Andrew Strominger | 1992-05-13 | Recently Callan, Giddings, Harvey and the author derived a set of one-loop semiclassical equations describing black hole formation/evaporation in two-dimensional dilaton gravity conformally coupled to |
[Global Analysis of New Gravitational Singularities in String and | |||
Particle Theories](http://arxiv.org/abs/hep-th/9205037v1) | I. Bars, K. Sfetsos | 1992-05-13 | We present a global analysis of the geometries that arise in non-compact current algebra (or gauged WZW) coset models of strings and particles propagating in curved space-time. The simplest case is the 2d black hole. In higher dimensions these geometries describe new and much more complex singularities. For string and particle theories (defined in the text) we introduce general methods for identifying global coordinates and give the general exact solution for the geodesics for any gauged WZW model for any number of dimensions. We then specialize to the 3d geometries associated with pinched double trousers". It can be pictured as the world sheet of two closed strings that join into a single closed string and then split into two closed strings, but with a pinch in each leg of the trousers. The second sector has a singularity surface with the topology of double saddle", pictured as the world sheets of two infinite open strings that come close but do not touch. We discuss the geodesicaly complete spaces on each side of these surfaces and interpret the motion of particles in physical terms. A cosmological interpretation is suggested and comments are mode on possible physical applications. |
Cosmological String Backgrounds from Gauged WZW Models | C. Kounnas, D. Luest | 1992-05-15 | We discuss the four-dimensional target-space interpretation of bosonic strings based on gauged WZW models, in particular of those based on the non-compact coset space |
[A Non Degenerate Semi-Classical Lagrangian for Dilaton-Gravity in Two | |||
Dimensions](http://arxiv.org/abs/hep-th/9205053v1) | Noureddine Mohammedi | 1992-05-15 | An action for two dimensional gravity conformally coupled to two dilaton-type fields is analysed. Classically, the theory has some exact solutions. These include configurations representing black holes. A semi-classical theory is obtained by assuming that these singular solutions are caused by the collapse of some matter fields. The semi-classical equations of motion reveal then that any generic solution must have a flat geometry. |
Quantum-Mechanical Scattering of Charged Black Holes | Jennie Traschen, Robert Ferrel | 1992-05-18 | We describe the quantum mechanical scattering of slowly moving maximally charged black holes. Our technique is to develop a canonical quantization procedure on the parameter space of possible static classical solutions. With this, we compute the capture cross sections for the scattering of two black holes. Finally, we discuss how quantization on this parameter space relates to quantization of the degrees of freedom of the gravitational field. |
Edge Currents and Vertex Operators for Chern-Simons Gravity | G. Bimonte, K. S. Gupta, A. Stern | 1992-05-20 | We apply elementary canonical methods for the quantization of 2+1 dimensional gravity, where the dynamics is given by E. Witten's |
Grand Canonical Partition Function of a 2-dimensional Hubbard Model | I. M. Barbour, E. G. Klepfish | 1992-05-26 | We present a new technique for a numerical analysis of the phase structure of the 2D Hubbard model as a function of the hole chemical potential. The grand canonical partition function for the model is obtained via Monte Carlo simulations. The dependence of the hole occupation number on the chemical potential and the temperature is evaluated. These calculations, together with a study of the Yang-Lee zeros of the grand canonical partition function, show evidence of a phase transition at zero temperature and particle density below half-filling. The binding energy of a pair of holes is calculated in the low temperature regime and the possibility for pairing is explored. |
About some exact solutions for 2+1 gravity coupled to gauge fields | Ian I. Kogan | 1992-05-26 | Some exact static solutions for Einstein gravity in 2+1 dimensions coupled to abelian gauge field are discussed. Some of these solutions are three-dimensional analogs of the Schwarzschild black holes. The metrics in the regions inside and outside the horison are connected by the changing of the Planck mass sign. |
Liouville Models of Black Hole Evaporation | Adel Bilal, Curtis Callan | 1992-05-27 | We construct new theories of dilation gravity coupled to conformal matter which are exact |
[Lattice distortion and energy level structures in doped C_{60} and | |||
C_{70} studied with the extended Su-Schrieffer-Heeger model: Polaron | |||
excitations and optical absorption](http://arxiv.org/abs/cond-mat/9205014v1) | Kikuo Harigaya | 1992-05-27 | We extend the Su-Schrieffer-Heeger model of polyacetylene to C_{60} and C_{70} molecules, and solve numerically. The calculations of the undoped systems agree well with the known results. When the system (C_{60} or C_{70}) is doped with one or two electrons (or holes), the additional charges accumulate almost along an equatorial line of the molecule. The dimerization becomes weaker almost along the same line. Two energy levels intrude largely in the gap. The intrusion is larger in C_{70} than in C_{60}. Therefore, polarons'' are predicted in doped buckminster- fullerenes. We calculate optical absorption coefficient for C_{60} in order to look at how polarons'' will be observed. It is predicted that there appears a new peak at the lower energy than the intergap transition peaks. It is also found that C_{60} and C_{70} are related mutually with respect to electronical structures as well as lattice geometries. (to be published in Phys. Rev. B 45, June 15 issue) |
[Matching Conditions and Gravitational Collapse in Two-Dimensional | |||
Gravity](http://arxiv.org/abs/hep-th/9205098v1) | R. B. Mann, S. F. Ross | 1992-05-27 | The general theory of matching conditions is developed for gravitational theories in two spacetime dimensions. Models inspired from general relativity and from string theory are considered. These conditions are used to study collapsing dust solutions in spacetimes with non-zero cosmological constant, demonstrating how two-dimensional black holes can arise as the endpoint of such collapse processes. |
Information Loss and Anomalous Scattering | Amanda Peet, Leonard Susskind, Larus Thorlacius | 1992-05-30 | The approach of 't Hooft to the puzzles of black hole evaporation can be applied to a simpler system with analogous features. The system is |
Symmetries of String Effective Action and Space-Time Geometry | S. Pratik Khastgir, Jnanadeva Maharana | 1992-06-02 | Two dimensional charged black hole solution is obtained by implementing an |
Dilaton-Axion hair for slowly rotating Kerr black holes | S. Mignemi, N. R. Stewart | 1992-06-04 | Campbell et al. demonstrated the existence of axion hair'' for Kerr black holes due to the non-trivial Lorentz Chern-Simons term and calculated it explicitly for the case of slow rotation. Here we consider the dilaton coupling to the axion field strength, consistent with low energy string theory and calculate the dilaton hair'' arising from this specific axion source. |
Black Hole Physics from Liouville Theory | S. P. de Alwis | 1992-06-04 | In a previous paper it was shown that the quantum consistency conditions for the dilaton-gravity theory of Callan et al., imply that the cosmological constant term undergoes a dilaton dependent renormalization, in such a manner that the theory can be written as a Liouville-like theory. In this paper we discuss the physical interpretation of the solutions of this theory. In particular we demonstrate explicitly how quantum corrections tame the black hole singularity. Also under the assumption that in asymptotically Minkowski coordinates, there are no incoming or outgoing ghosts, we show that the Hawking radiation rate is independent of the number of matter fields and is determined by the ghost conformal anomaly. |
Conservation Laws and 2D Black Holes in Dilaton Gravity | R. B. Mann | 1992-06-10 | A very general class of Lagrangians which couple scalar fields to gravitation and matter in two spacetime dimensions is investigated. It is shown that a vector field exists along whose flow lines the stress-energy tensor is conserved, regardless of whether or not the equations of motion are satisfied or if any Killing vectors exist. Conditions necessary for the existence of Killing vectors are derived. A new set of 2D black hole solutions is obtained for one particular member within this class of Lagrangians. One such solution bears an interesting resemblance to the 2D string-theoretic black hole, yet contains markedly different thermodynamic properties. |
[Conformally Exact Results for SL(2,R)\times SO(1,1)^{d-2}/SO(1,1) Coset | |||
Models](http://arxiv.org/abs/hep-th/9206048v1) | Konstadinos Sfetsos | 1992-06-10 | Using the conformal invariance of the |
Two Dimensional String Theory And Black Holes | Edward Witten | 1992-06-17 | This lecture surveys a few loosely related topics, ranging from the scarcity of quantum field theories -- and the role that this has played, and still plays, in physics -- to paradoxes involving black holes in soluble two dimensional string theory and the question of whether naked singularities might be of even greater interest to string theorists than black holes. |
The Endpoint of Hawking Evaporation | J. Russo, L. Susskind, L. Thorlacius | 1992-06-17 | The formation and semi-classical evaporation of two-dimensional black holes is studied in an exactly solvable model. Above a certain threshold energy flux, collapsing matter forms a singularity inside an apparent horizon. As the black hole evaporates the apparent horizon recedes and meets the singularity in a finite proper time. The singularity emerges naked and future evolution of the geometry requires boundary conditions to be imposed there. There is a natural choice of boundary conditions which match the evaporated black hole solution onto the linear dilaton vacuum. Below the threshold energy flux no horizon forms and boundary conditions can be imposed where infalling matter is reflected from a time-like naked singularity. All information is recovered at spatial infinity in this case. |
Uniqueness of the Axionic Kerr Black Hole | Rue-Ron Hsu, Green Huang, Wei-Fu Lin | 1992-06-17 | Under the axisymmetry and under the invarance of simultaneous inversion of time and azimuthal angle, we show that the axionic Kerr black hole is the |
Quantum Theory of Dilaton Gravity in 1+1 Dimensions | K. Hamada | 1992-06-18 | We discuss the quantum theory of 1+1 dimensional dilaton gravity, which is an interesting model with analogous features to the spherically symmetric gravitational systems in 3+1 dimensions. The functional measures over the metrics and the dilaton field are explicitly evaluated and the diffeomorphism invariance is completely fixed in conformal gauge by using the technique developed in the two dimensional quantum gravity. We argue the relations to the ADM formalism. The physical state conditions reduce to the usual Wheeler-DeWitt equations when the dilaton $\df^2 ~ (=\e^{-2\phi}) $ is large enough compared with |
[World-Sheet Duality, Space-Time Foam, and the Quantum Fate of a Stringy | |||
Black Hole](http://arxiv.org/abs/hep-th/9206077v2) | John Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1992-06-19 | We interpret Minkowski black holes as world-sheet {\it spikes } which are related by world-sheet { \it duality} to {\it vortices } that correspond to Euclidean black holes. These world-sheet defects induce defects in the gauge fields of the corresponding coset Wess-Zumino descriptions of spherically-symmetric black holes. The low-temperature target space-time foam is a Minkowski black hole (spike) plasma with confined Euclidean black holes (vortices). The high-temperature phase is a {\it dense} vortex plasma described by a topological gauge field theory on the world-sheet, which possesses enhanced symmetry as in the target space-time singularity at the core of a black hole. Quantum decay via higher-genus effects induces a back-reaction which causes a Minkowski black hole to lose mass until it is indistinguishable from intrinsic fluctuations in the space-time foam. |
Charged Dilatonic Black Hole and Hawking Radiation in Two Dimensions | Shin'ichi Nojiri, Ichiro Oda | 1992-06-24 | We consider Callan, Giddings, Harvey and Strominger's (CGHS) two dimensional dilatonic gravity with electromagnetic interactions. This model can be also solved classically. Among the solutions describing static black holes, there exist extremal solutions which have zero temperatures. In the extremal solutions, the space-time metric is not singular. We also obtain the solutions describing charged matter (chiral fermions) collapsing into black holes. Through the collapsing, not only future horizon but past horizon is also shifted. The quantum corrections including chiral anomaly are also discussed. In a way similar to CGHS model, the curvature singularity also appeared, except extremal case, when the matter collapsing. The screening effects due to the chiral anomaly have a tendency to cloak the singularity |
String Theory, Black Holes, and SL(2,R) Current Algebra | Shyamoli Chaudhuri, Joseph D. Lykken | 1992-06-29 | We analyse in detail the |
Exactly Solvable Models of 2d Dilaton Quantum Gravity | A. Mikovic | 1992-07-02 | We study canonical quantization of a class of 2d dilaton gravity models, which contains the model proposed by Callan, Giddings, Harvey and Strominger. A set of non-canonical phase space variables is found, forming an |
Low voltage conductance of small tunnel junctions | F. Guinea, M. Ueda | 1992-07-06 | A discrete charge transfer in a small tunnel junction where Coulomb interactions are important can excite electron-hole pairs near the Fermi level. We use a simple model to study the associated nonequilibrium properties and found two novel effects: (i) for junctions with electrodes of the same electronic properties, a leakage current exists within the Coulomb gap even when the environmental impedance is infinite; (ii) for junctions with electrodes of different electronic properties, the differential conductance diverges when a net interaction between conduction electrons is attractive, and it is strongly suppressed for a net repulsive interaction. |
[One-Loop Renormalization in Two-Dimensional Matter-Dilaton Quantum | |||
Gravity and Charged Black Holes](http://arxiv.org/abs/hep-th/9207046v1) | E. Elizalde, S. D. Odintsov | 1992-07-14 | The quantum properties of two-dimensional matter-dilaton gravity ---which includes a large family of actions for two-dimensional gravity (in particular, string-inspired models)--- are investigated. The one-loop divergences in linear covariant gauges are calculated and the structure of the one-loop renormalization is studied. The explicit forms of the dilaton potential, dilaton-Maxwell, and dilaton-scalar couplings for which the theory is one-loop multiplicatively renormalizable are found. A comparison with the one-loop renormalization structure of four-dimensional gravity-matter theory is given. Charged multiple-horizon black holes which appear in the model are also considered. |
Electric Magnetic Duality in String Theory | Ashoke Sen | 1992-07-15 | The electric-magnetic duality transformation in four dimensional heterotic string theory discussed by Shapere, Trivedi and Wilczek is shown to be an exact symmetry of the equations of motion of low energy effective field theory even after including the scalar and the vector fields, arising due to compactification, in the effective field theory. Using this duality transformation we construct rotating black hole solutions in the effective field theory carrying both, electric and magnetic charges. The spectrum of extremal magnetically charged black holes turns out to be similar to that of electrically charged elementary string excitations. We also discuss the possibility that the duality symmetry is an exact symmetry of the full string theory under which electrically charged elementary string excitations get exchanged with magnetically charged soliton like solutions. This proposal might be made concrete following the suggestion of Dabholkar et. al. that fundamental strings may be regarded as soliton like classical solutions in the effective field theory. |
[Vortex motion and the Hall effect in type II superconductors: a time | |||
dependent Ginzburg-Landau theory approach](http://arxiv.org/abs/cond-mat/9207018v1) | Alan T. Dorsey | 1992-07-15 | Vortex motion in type II superconductors is studied starting from a variant of the time dependent Ginzburg-Landau equations, in which the order parameter relaxation time is taken to be complex. Using a method due to Gor'kov and Kopnin, we derive an equation of motion for a single vortex ( |
The vacuum polarization around an axionic stringy black hole | A. Carlini, A. Treves, F. Fucito, M. Martellini | 1992-07-16 | We consider the effect of vacuum polarization around the horizon of a 4 dimensional axionic stringy black hole. In the extreme degenerate limit ( |
Duality in Multi-layered Quantum Hall Systems | C. Ting | 1992-07-17 | The braid group dynamics captures the fractional quantum Hall effect (FQHE) as a manifestation of puncture phase. When the dynamics is generalized for particles on a multi-sheeted surface, we obtain new tools which determine the fractional charges, the quantum statistics, and the filling factors of the multi-layered FQHE. A many-quasi-hole wavefunction is proposed for the bilayered samples. We also predict a |
Mutual statistics, braid group, and the fractional quantum Hall effect | C. Ting | 1992-07-17 | We show that the notion of mutual statistics arises naturally from the representation theory of the braid group over the multi-sheeted surface. A Hamiltonian which describes particles moving on the double-sheeted surface is proposed as a model for the bilayered fractional quantum Hall effect (FQHE) discovered recently. We explicitly show that the quasi-holes of the bilayered Hall fluid display fractional mutual statistics. A model for 3-dimensional FQHE using the multi-layered sample is suggested. |
[Semi-classical Approach to Charged Dilatonic Black Hole in Two | |||
Dimensions](http://arxiv.org/abs/hep-th/9207077v2) | Shin'ichi Nojiri, Ichiro Oda | 1992-07-22 | We consider exactly solvable semi-classical theory of two dimensional dilatonic gravity with electromagnetic interactions. As was done in the paper by Russo, Susskind and Thorlacius, the term which changes the kinetic term is added to the action. The theory contains massless fermions as matter fields and there appear the quantum corrections including chiral anomaly. The screening effect due to the chiral anomaly has a tendency to cloak the singularity. In a region of the parameter space, the essential behavior of the theory is similar to that of Callan, Giddings, Harvey and Strominger's dilatonic black hole theory modified in the paper by Russo, Susskind and Thorlacius and the singularity formed by the collapsing matter emerges naked. We find, however, another region of the parameter space where the singularity disappears in a finite proper time. Furthermore, in the region of the parameter space, there appears a discontinuity in the metric on the trajectory of the collapsing matter, which would be a signal of topology change |
Dilatonic Black Holes, Naked Singularities and Strings | P. H. Cox, B. Harms, Y. Leblanc | 1992-07-23 | We extend a previous calculation which treated Schwarschild black hole horizons as quantum mechanical objects to the case of a charged, dilaton black hole. We show that for a unique value of the dilaton parameter `a', which is determined by the condition of unitarity of the S matrix, black holes transform at the extremal limit into strings. |
The No-Hair Theorem for the Abelian Higgs Model | Amitabha Lahiri | 1992-07-27 | We consider the general procedure for proving no-hair theorems for static, spherically symmetric black holes. We apply this method to the abelian Higgs model and find a proof of the no-hair conjecture that circumvents the objections raised against the original proof due to Adler and Pearson. |
The Dirac Equation Is Separable On The Dyon Black Hole Metric | Ä°brahim Semiz | 1992-07-28 | Using the tetrad formalism, we carry out the separation of variables for the massive complex Dirac equation in the gravitational and electromagnetic field of a four-parameter (mass, angular momentum, electric and magnetic charges) black hole. |
String Theory Modifies Quantum Mechanics | John Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1992-07-29 | We argue that the light particles in string theory obey an effective quantum mechanics modified by the inclusion of a quantum-gravitational friction term, induced by unavoidable couplings to unobserved massive string states in the space-time foam. This term is related to the |
Black Holes from Nucleating Strings | Jaume Garriga, Alexander Vilenkin | 1992-08-06 | We evaluate the probability that a loop of string that has spontaneously nucleated during inflation will form a black hole upon collapse, after the end of inflation. We then use the observational bounds on the density of primordial black holes to put constraints on the parameters of the model. Other constraints from the distortions of the microwave background and emission of gravitational radiation by the loops are considered. Also, observational constraints on domain wall nucleation and monopole pair production during inflation are briefly discussed. |
Thermodynamics of Two-Dimensional Black-Holes | Chiara R. Nappi, Andrea Pasquinucci | 1992-08-11 | We explore the thermodynamics of a general class of two dimensional dilatonic black-holes. A simple prescription is given that allows us to compute the mass, entropy and thermodynamic potentials, with results in agreement with those obtained by other methods, when available. |
Gravitationally Collapsing Dust in $(2+1)$ Dimensions | S. F. Ross, R. B. Mann | 1992-08-13 | We investigate the circumstances under which gravitationally collapsing dust can form a black hole in three-dimensional spacetime. |
[The Last Three Minutes: Issues in Gravitational Wave Measurements of | |||
Coalescing Compact Binaries](http://arxiv.org/abs/astro-ph/9208005v1) | Curt Cutler, Theocharis A. Apostolatos, Lars Bildsten, Lee Samuel Finn, Eanna E. Flanagan, Daniel Kennefick, Dragoljubov M. Markovic, Amos Ori, Eric Poisson, Gerald Jay Sussman, Kip S. Thorne | 1992-08-25 | Gravitational-wave interferometers are expected to monitor the last three minutes of inspiral and final coalescence of neutron star and black hole binaries at distances approaching cosmological, where the event rate may be many per year. Because the binary's accumulated orbital phase can be measured to a fractional accuracy |
Binary Black Holes in Stationary Orbits | Sandip K. Chakrabarti | 1992-08-27 | We show that under certain astrophysical conditions a binary system consisting of two compact objects can be stabilized against indefinite shrinking of orbits due to the emission of gravitational radiation. In this case, the lighter binary companion settles down to a stable orbit when the loss of the angular momentum due to gravitational radiation becomes equal to its gain from the accreting matter from the disk around the more massive primary. We claim that such systems can be stable against small perturbations and can be regarded as steady emitters of gravitational waves of constant frequency and amplitude. Furthermore, X-rays emitted by the secondary can also produce astrophysically interesting situations when coupled with gravitational lensing and Doppler effects. |
Statistical Mechanics of Extended Black Objects | B. Harms, Y. Leblanc | 1992-08-27 | We extend the considerations of a previous paper on black hole statistical mechanics to the case of black extended objects such as black strings and black membranes in 10-dimensional space-time. We obtain a general expression for the Euclidean action of quantum black p-branes and derive their corresponding degeneracy of states. The statistical mechanics of a gas of black p-branes is then analyzed in the microcanonical ensemble. As in the case of black holes, the equilibrium state is not thermal and the stable configuration is the one for which a single black object carries most of the energy. Again, neutral black p-branes obey the bootstrap condition and it is then possible to argue that their scattering amplitudes satisfy crossing symmetry. Finally, arguments identifying quantum black p-branes with ordinary quantum branes of different dimensionality are presented. |
Electric-Magnetic Duality and Supersymmetry in Stringy Black Holes | Tomás OrtĂn | 1992-08-31 | We present a generalization of the |
Semiclassical Approach to Black Hole Evaporation | David A. Lowe | 1992-09-02 | Black hole evaporation may lead to massive or massless remnants, or naked singularities. This paper investigates this process in the context of two quite different two dimensional black hole models. The first is the original CGHS model, the second is another two dimensional dilaton-gravity model, but with properties much closer to physics in the real, four dimensional, world. Numerical simulations are performed of the formation and subsequent evaporation of black holes and the results are found to agree qualitatively with the exactly solved modified CGHS models, namely that the semiclassical approximation breaks down just before a naked singularity appears. |
Cosmic Censorship in Two-Dimensional Gravity | J. Russo, L. Susskind, L. Thorlacius | 1992-09-04 | A weak version of the cosmic censorship hypothesis is implemented as a set of boundary conditions on exact semi-classical solutions of two-dimensional dilaton gravity. These boundary conditions reflect low-energy matter from the strong coupling region and they also serve to stabilize the vacuum of the theory against decay into negative energy states. Information about low-energy incoming matter can be recovered in the final state but at high energy black holes are formed and inevitably lead to information loss at the semi-classical level. |
[The String Universe: High |
|||
Conductor?](http://arxiv.org/abs/hep-th/9209013v1) | John Ellis, N. E. Mavromatos, D. V. Nanopoulos | 1992-09-04 | Our answer is the latter. Space-time singularities, including the initial one, are described by world-sheet topological Abelian gauge theories with a Chern-Simons term. Their effective |
Results on exact solutions of low energy string theory | David Garfinkle | 1992-09-05 | A family of solutions to low energy string theory is found. These solutions represent waves traveling along "extremal black strings" |
[Spin texture in weakly doped |
|||
correlation length and Raman scattering experiments](http://arxiv.org/abs/cond-mat/9209007v1) | R. J. Gooding, A. Mailhot | 1992-09-08 | A model of |
Boosting Away Singularities from Conformal String Backgrounds | M. Gasperini, J. Maharana, G. Veneziano | 1992-09-15 | Generalizing our previous work, we show how |
Quantum Aspects of Black Holes | J. A. Harvey, A. Strominger | 1992-09-16 | This review is based on lectures given at the 1992 Trieste Spring School on String Theory and Quantum Gravity and at the 1992 TASI Summer School in Boulder, Colorado. |
[Numerical Study of the Wheatley-Hsu-Anderson Interlayer Tunneling | |||
mechanism of High |
M. Arjunwadkar, G. Baskaran, R. Basu, V. N. Muthukumar | 1992-09-16 | We present results obtained (by exact diagonalization) for the problem of two t-J planes with an interlayer coupling |
Do Black Holes Destroy Information? | John Preskill | 1992-09-16 | I review the information loss paradox that was first formulated by Hawking, and discuss possible ways of resolving it. All proposed solutions have serious drawbacks. I conclude that the information loss paradox may well presage a revolution in fundamental physics. (To appear in the proceedings of the International Symposium on Black Holes, Membranes, Wormholes, and Superstrings.) |
Quantum Dilaton Gravity in the Light-cone Gauge | Xiang Shen | 1992-09-18 | Recently, models of two-dimensional dilaton gravity have been shown to admit classical black-hole solutions that exhibit Hawking radiation at the semi-classical level. These classical and semi-classical analyses have been performed in conformal gauge. We show in this paper that a similar analysis in the light--cone gauge leads to the same results. Moreover, quantization of matter fields in light--cone gauge can be naturally extended to include quantizing the metric field {\it `a la} KPZ. We argue that this may provide a new framework to address many issues associated to black-hole physics. |
[Photoinduced charge separation in Q1D heterojunction materials: Evidence | |||
for electron-hole pair separation in mixed-halide |
L. A. Worl, S. C. Huckett, B. I. Swanson, A. Saxena, A. R. Bishop, J. Tinka Gammel | 1992-09-19 | Resonance Raman experiments on doped and photoexcited single crystals of mixed-halide |
Black Holes with a Massive Dilaton | R. Gregory, J. A. Harvey | 1992-09-19 | The modifications of dilaton black holes which result when the dilaton acquires a mass are investigated. We derive some general constraints on the number of horizons of the black hole and argue that if the product of the black hole charge |
Polaron excitations in fullerenes: Theory as pi-conjugated systems | Kikuo Harigaya | 1992-09-20 | We review the recent theoretical treatment of fullerenes as pi-conjugated systems. Polaronic properties due to the Jahn-Teller type effects are mainly discussed. (1) A Su-Schrieffer-Heeger type electron-phonon model is applied to fullerenes: C_60 and C_70, and is solved with the adiabatic approximation to phonons. When the system (C_60 or C_70) is doped with one or two electrons (or holes), the additional charges accumulate along almost an equatorial line of the molecule. The dimerization becomes the weakest along the same line. Two energy levels, the occupied state and the empty state, intrude largely in the gap. The intrusion is larger in C_70 than in C_60. These are ``polarons'' in doped fullerenes. It is also found that C_60 and C_70 are related mutually with respect to electronical structures as well as lattice geometries. (2) We apply the model to the fullerene epoxide C_60O. It has the polaron-type lattice distortion around the oxygen, and also shows the energy level intrusion in the gap. (3) Optical properties of C_60 are calculated and discussed. In the absorption of the doped molecule, a new peak structure is present owing to the polaronic distortion. In the luminescence of the neutral C_60, the spacing between H_g(8)-phonon side-band peaks and the relative intensities agree well with experiments. In the dispersion of the third harmonic generation, the magnitudes of |
Detection, Measurement and Gravitational Radiation | Lee Samuel Finn | 1992-09-24 | Here I examine how to determine the sensitivity of the LIGO, VIRGO, and LAGOS gravitational wave detectors to sources of gravitational radiation by considering the process by which data are analyzed in a noisy detector. By constructing the probability that the detector output is consistent with the presence of a signal, I show how to (1) quantify the uncertainty that the output contains a signal and is not simply noise, and (2) construct the probability distribution that the signal parameterization has a certain value. From the distribution and its mode I determine volumes most likely'' response of the detector to a signal. I exploit the techniques just described to determine the most likely'' volumes |
Domain Walls in $N=1$ Supergravity | Mirjam Cvetic, Stephen Griffies | 1992-09-28 | We discuss a study of domain walls in |
[Dilatonic Supergravity in Two Dimensions and the Disappearance of | |||
Quantum Black Hole](http://arxiv.org/abs/hep-th/9209118v1) | Shin'ichi Nojiri, Ichiro Oda | 1992-09-29 | We analyze a supergravity theory coupled to a dilaton and superconformal matters in two dimensions. This theory is classically soluble and we find all the solutions appeared in Callan, Giddings, Harvey and Strominger's dilatonic gravity also satisfy the constraints and the equations of motion in this supersymmetric theory. We quantize this theory by following the procedure of Distler, Hlousek and Kawai. In the quantum action, the cosmological term is renormalized to vanish. As a result, any solution corresponding to classical black hole does not appear in the quantum theory, which should be compared with the non-supersymmetric case. |
$W_{\infty} Algebra in Two-Dimensional Black Hole | T. Eguchi, H. Kanno, S. -K. Yang | 1992-09-29 | We study the |
Dilaton-Axion Symmetry | John H. Schwarz | 1992-09-29 | The heterotic string compactified on a six-torus is described by a low-energy effective action consisting of N=4 supergravity coupled to N=4 super Yang-Mills, a theory that was studied in detail many years ago. By explicitly carrying out the dimensional reduction of the massless fields, we obtain the bosonic sector of this theory. In the Abelian case the action is written with manifest global |
Spontaneous CP Violation, Small Instanton and Invisible Axion | Soo-Jong Rey | 1992-09-30 | I propose a variant invisible axion model of spontaneous CP violation at the electroweak scale without CP domain wall and `strong CP' problems. Both large size QCD and small size non-QCD instantons break CP and Peccei-Quinn symmetries, and render cosmologically harmful CP domain walls unstable. The decaying epoch depends on size of small instanton effects, and is around 100 eV if the current neutron electric dipole moment bound is maximally saturated. The model satisfies constraints from primordial D and He photo-dissociation and black hole formation, while producing cosmologically interesting size of gravitational waves and galaxy-scale density perturbations. |
Poincaré Gauge Theories for Lineal Garvity | G. Grignani, G. Nardelli | 1992-09-30 | We have shown that two of the most studied models of lineal gravities - Liouville gravity and a ``string-inspired'' model exhibiting the main characteristic features of a black-hole solution - can be formulated as gauge invariant theories of the Poincar'e group. The gauge invariant couplings to matter (particles, scalar and spinor fields) and explicit solutions for some matter field configurations, are provided. It is shown that both the models, as well as the couplings to matter, can be obtained as suitable dimensional reductions of a 2+1-dimensional ISO(2,1) gauge invariant theory. |
The Microcanonical Functional Integral. I. The Gravitational Field | J. David Brown, James W. York | 1992-09-30 | The gravitational field in a spatially finite region is described as a microcanonical system. The density of states |
Black Holes Coupled to a Massive Dilaton | J. Horne, G. Horowitz | 1992-10-02 | We investigate charged black holes coupled to a massive dilaton. It is shown that black holes which are large compared to the Compton wavelength of the dilaton resemble the Reissner-Nordstr"om solution, while those which are smaller than this scale resemble the massless dilaton solutions. Black holes of order the Compton wavelength of the dilaton can have wormholes outside the event horizon in the string metric. Unlike all previous black hole solutions, nearly extremal and extremal black holes (of any size) repel each other. We argue that extremal black holes are quantum mechanically unstable to decay into several widely separated black holes. We present analytic arguments and extensive numerical results to support these conclusions. |
[Supersymmetry and Positive Energy in Classical and Quantum | |||
Two-Dimensional Dilaton Gravity](http://arxiv.org/abs/hep-th/9210017v1) | Youngchul Park, Andrew Strominger | 1992-10-02 | An |
Duality Symmetries from Non--Abelian Isometries in String Theories | Xenia C. de la Ossa, Fernando Quevedo | 1992-10-05 | In string theory it is known that abelian isometries in the sigma model lead to target space duality. We generalize this duality to backgrounds with non--abelian isometries. The procedure we follow consists of gauging the isometries of the original action and constraining the field strength |
Charged String-like Solutions of Low-energy Heterotic String Theory | Daniel Waldram | 1992-10-06 | Two string-like solutions to the equations of motion of the low-energy effective action for the heterotic string are found, each a source of electric and magnetic fields. The first carries an electric current equal to the electric charge per unit length and is the most general solution which preserves one half of the supersymmetries. The second is the most general charged solution with an event horizon, a `black string'. The relationship of the solutions to fundamental, macroscopic heterotic strings is discussed, and in particular it is shown that any stable state of such a fundamental string also preserves one half of the supersymmetries, in the same manner as the first solution. |
Strings and QCD? | Joseph Polchinski | 1992-10-08 | Is large-$N$ QCD equivalent to a string theory? Maybe, maybe not. I review various attempts to answer the question. |
Black Holes and Solitons in String Theory | Ashoke Sen | 1992-10-09 | In this review, I discuss a general method for constructing classical solutions of the equations of motion arising in the effective low energy string theory, and discuss specific applications of this method. (Based on talks given at the Johns Hopkins Workshop held at Goteborg, June 8-10, 1992, and ICTP Summer Workshop held at Trieste, July 2-3, 1992) |
Time-dependent perturbations in two-dimensional String Black Holes | G. A. Diamandis, B. C. Georgalas, X. Maintas, N. E. Mavromatos | 1992-10-09 | We discuss time-dependent perturbations (induced by matter fields) of a black-hole background in tree-level two-dimensional string theory. We analyse the linearized case and show the possibility of having black-hole solutions with time-dependent horizons. The latter exist only in the presence of time-dependent `tachyon' matter fields, which constitute the only propagating degrees of freedom in two-dimensional string theory. For real tachyon field configurations it is not possible to obtain solutions with horizons shrinking to a point. On the other hand, such a possibility seems to be realized in the case of string black-hole models formulated on higher world-sheet genera. We connect this latter result with black hole evaporation/decay at a quantum level.} |
Superstrings on Curved Spacetimes | Itzhak Bars | 1992-10-15 | In this lecture I summarize recent developments on strings propagating in curved spacetime. Exact conformal field theories that describe gravitational backgrounds such as black holes and more intricate gravitational singularities have been discovered and investigated at the classical and quantum level. These models are described by gauged Wess-Zumino-Witten models, or equivalently current algebra G/H coset models based on non-compact groups, with a single time coordinate. The classification of such models for all dimensions is complete. Furthermore the heterotic superstrings in curved spacetime based on non-compact groups have also been constructed. For many of the |
[A Conformal Affine Toda Model of 2D Black Holes: A Quantum Study of the | |||
Evaporation End-Point](http://arxiv.org/abs/hep-th/9210088v1) | F. Belgiorno, A. S. Cattaneo, M. Martellini, F. Fucito | 1992-10-16 | In this paper we reformulate the dilaton-gravity theory of Callan \etal\ as a new effective conformal field theory which turns out to be a generalization of the so-called |
Gravitational Collapse in 1+1 Dimensions and Quantum Gravity | K. Hamada | 1992-10-19 | We investigate the quantum theory of 1+1 dimensional dilaton gravity, which is an interesting toy model of the black hole dynamics. The functional measures of gravity part are explicitly evaluated and derive the Wheeler-DeWitt like equations as physical state conditions. In ADM formalism the measures are very ambiguous, but in our formalism they are explicitly defined. Then the new features which are not seen in ADM formalism come out. A singularity appears at |
The Dark Side of String Theory: Black Holes and Black Strings | Gary T. Horowitz | 1992-10-21 | Solutions to low energy string theory describing black holes and black strings are reviewed. Many of these solutions can be obtained by applying simple solution generating transformations to the Schwarzschild metric. In a few cases, the corresponding exact conformal field theory is known. Various properties of these solutions are discussed including their global structure, singularities, and Hawking temperature. (This review is based on lectures given at the 1992 Trieste Spring School on String Theory and Quantum Gravity.) |
Stringy Quantum Effects in 2-Dimensional Black-Hole | Avinash Dhar, Gautam Mandal, Spenta R. Wadia | 1992-10-22 | We discuss the classical 2-dim. black-hole in the framework of the non-perturbative formulation (in terms of non-relativistic fermions) of c=1 string field theory. We identify an off-shell operator whose classical equation of motion is that of tachyon in the classical graviton-dilaton black-hole background. The black-hole `singularity' is identified with the fermi surface in the phase space of a single fermion, and as such is a consequence of the semi-classical approximation. An exact treatment reveals that stringy quantum effects wash away the classical singularity. |
Correlaction Effects on the Band Gap of Conducting Polymers | C. Q. Wu | 1992-10-23 | By applying the projection technique to the computation of excitation energies, we study the correlation effects on the band gap of conducting polymers. In the presence of an additional electron or hole, the correlation induces a polarization cloud around the addi- tional particle, which forms a polaron. For the excitation energy of a polaron,there is a competition between a {\it loss} of the correla- tion energy in the ground state and a {\it gain} of polarization energy. For the Hubbard interaction, the {\it loss} of correlation energy is dominant and correlations increase the band gap.However,for long-range interactions, the {\it gain} of polarization energy is dominant and correlations decrease the band gap. Screening the long- range interaction suppresses the {\it gain}of the polarization energy so that correlations again increase the band gap.A small dimerization is always favorable to the correlation effects. For {\it trans}-poly- acetylene, we obtain the on-site repulsion $U=4.4$eV and the nearest- neighbor interaction |
Quantum Effects in Black Hole Interiors | Warren G. Anderson, Patrick R. Brady, Werner Israel, Sharon M. Morsink | 1992-10-23 | The Weyl curvature inside a black hole formed in a generic collapse grows, classically without bound, near to the inner horizon, due to partial absorption and blueshifting of the radiative tail of the collapse. Using a spherical model, we examine how this growth is modified by quantum effects of conformally coupled massless fields. |
Is Quantum Spacetime Foam Unstable? | Ian H. Redmount, Wai-Mo Suen | 1992-10-28 | A very simple wormhole geometry is considered as a model of a mode of topological fluctutation in Planck-scale spacetime foam. Quantum dynamics of the hole reduces to quantum mechanics of one variable, throat radius, and admits a WKB analysis. The hole is quantum-mechanically unstable: It has no bound states. Wormhole wave functions must eventually leak to large radii. This suggests that stability considerations along these lines may place strong constraints on the nature and even the existence of spacetime foam. |
[Coset Models Obtained by Twisting WZW Models and Stringy Charged Black | |||
Holes in Four Dimensions](http://arxiv.org/abs/hep-th/9210160v2) | David Gershon | 1992-10-31 | We show that several WZW coset models can be obtained by applying O(d,d) symmetry transformations (referred to as twisting) on WZW models. This leads to a conjecture that WZW models gauged by U(1)^n subgroup can be obtained by twisting (ungauged) WZW models. In addition, a class of solutions that describe charged black holes in four dimensions is derived by twisting SL(2,R)\times SU(2) WZW. |
[All Or Nothing: On the Small Fluctuations of Two-Dimensional | |||
String-Theoretic Black Holes](http://arxiv.org/abs/hep-th/9210165v3) | Gerald Gilbert, Eric Raiten | 1992-10-31 | A comprehensive analysis of small fluctuations about two-dimensional string-theoretic and string-inspired black holes is presented. It is shown with specific examples that two-dimensional black holes behave in a radically different way from all known black holes in four dimensions. For both the |
[Eluding the no-hair conjecture: Black holes in spontaneously broken | |||
gauge theories](http://arxiv.org/abs/hep-th/9211007v2) | Brian R. Greene, Samir D. Mathur, Christopher M. O'Neill | 1992-11-02 | We study regular and black hole solutions to the coupled classical Einstein--Yang-Mills--Higgs system. It has long been thought that black hole solutions in the spontaneously broken phase of such a theory could have no nontrivial field structure outside of the horizon. We first show that the standard black hole no-hair theorem underlying this belief, although true in the abelian setting, does not necessarily extend to the non-abelian case. This indicates the possibility of solutions with non-trivial gauge and Higgs configurations decaying exponentially {\it outside} the horizon. We then find such solutions by numerical integration of the classical equations for the case of |
Semiclassical Extremal Blackholes | Sandip P. Trivedi | 1992-11-03 | Extremal black holes are studied in a two dimensional model motivated by a dimensional reduction from four dimensions. Their quantum corrected geometry is calculated semiclassically and a mild singularity is shown to appear at the horizon. Extensions of the geometry past the horizon are not unique but there are continuations free from malevolent singularities. A few comments are made about the relevance of these results to four dimensions and to the study of black hole entropy and information loss. |
Chern--Simons Gravity from 3+1 Dimensional Gravity | G. Grignani, G. Nardelli | 1992-11-03 | In the context of a Poincar'e gauge theoretical formulation, pure gravity in 3+1-dimensions is dimensionally reduced to gravity in 2+1-dimensions with or without cosmological constant |
Black Hole Uncertainties | Ulf H. Danielsson | 1992-11-03 | In this work the quantum theory of two dimensional dilaton black holes is studied using the Wheeler De Witt equation. The solutions correspond to wave functions of the black hole. It is found that for an observer inside the horizon, there are uncertainty relations for the black hole mass and a parameter in the metric determining the Hawking flux. Only for a particular value of this parameter, can both be known with arbitrary accuracy. In the generic case there is instead a relation which is very similar to the so called string uncertainty relation. |
Entropy and Action of Dilaton Black Holes | Renata Kallosh, Tomas Ortin, Amanda Peet | 1992-11-04 | We present a detailed calculation of the entropy and action of |
Gauge Field Back-reaction on a Black Hole | David Hochberg, Thomas W. Kephart | 1992-11-05 | The order |
Black Hole Remnants and the Information Puzzle | T. Banks, M. O'Loughlin, A. Strominger | 1992-11-05 | Magnetically charged dilatonic black holes have a perturbatively infinite ground state degeneracy associated with an infinite volume throat region of the geometry. A simple argument based on causality is given that these states do not have a description as ordinary massive particles in a low-energy effective field theory. Pair production of magnetic black holes in a weak magnetic field is estimated in a weakly-coupled semiclassical expansion about an instanton and found to be finite, despite the infinite degeneracy of states. This suggests that these states may store the information apparently lost in black hole scattering processes. |
Centri`fugal' Force around a Black Hole | A. Y. Shiekh | 1992-11-08 | Besides having some very interesting perturbatively unstable orbits, it seems that for a Schwarzschild black hole, below |
[Gauge Formulation of the Spinning Black Hole in (2+1)-Dimensional | |||
Anti-de Sitter Space](http://arxiv.org/abs/gr-qc/9211013v1) | Daniel Cangemi, Martin Leblanc, Robert B. Mann | 1992-11-09 | We compute the group element of SO(2,2) associated with the spinning black hole found by Ba~nados, Teitelboim and Zanelli in (2+1)-dimensional anti-de Sitter space-time. We show that their metric is built with SO(2,2) gauge invariant quantities and satisfies Einstein's equations with negative cosmological constant everywhere except at |
Black hole formation in $c=1$ String Field Theory | J. Russo | 1992-11-12 | A suggestion on how black holes may appear in Das-Jevicki Collective field theory is given. We study the behaviour of a test' particle when energy is sent into the system. A perturbation moving near the potential barrier can create a large-distance black hole geometry where the seeming curvature singularity is at the position of the barrier. In the simplest static' case the exact |
Vacuum Polarisation and the Black Hole Singularity | W. G. Anderson, P. R. Brady, R. Camporesi | 1992-11-13 | In order to investigate the effects of vacuum polarisation on mass inflation singularities, we study a simple toy model of a charged black hole with cross flowing radial null dust which is homogeneous in the black hole interior. In the region |
Project is licensed under the MIT LICENSE
Your contributions are greatly appreciated! If you have any relevant paper you'd like to add, please feel free to create a pull request!