摘要:

In my talk I show a black string which is a foliation of anti-de Sitter (AdS) Schwarzschild black hole becomes classically stable if the size of black hole horizon is larger than the AdS radius even if the black string extends infinitely. I will also give a comment on the relation with the Gubser-Mitra conjecture. This talk is based on our paper (Phys. Rev. D64: 064010, 2001 [1]) which is a collaboration with Gungwon Kang. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454362

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

Gregory and Laflamme showed that certain nonextremal black strings (andp-branes) are unstable to linearized perturbations. It is widely believed that this instability will cause the black string horizon to classically pinch off and then quantum mechanically separate, resulting in higher dimensional black holes. We argue that this cannot happen. Under very mild assumptions, classical event horizons cannot pinch off. Instead, they settle down to new static black string solutions which are not translationally invariant along the string. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454363

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We have some candidates for the constructive definition of string theory based on ten dimensional super Yang-Mills theory reduced to various dimensions. Although there are some evidences that these models describe gravity, the way how the diffeomorphism invariance is realized is not clear. In this talk, we introduce some attempts of constructing new types of matrix models in which the symmetry of the gravity can be seen manifestry. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454364

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

An off-shell formulation is given for the supersymmetry in singular spaces that has recently been developed in an on-shell formalism by Bergshoeff, Kallosh and Van Proeyen using a supersymmetry singlet “coupling constant” field and a 4-form multiplier field in five-dimensional space-time. I also identify the 4D Weyl and matter multiplets induced on the boundary planes from the 5D bulk fields, and discuss in our superconformal framework how and when the bulk cosmological constant and the brane tensions of boundary planes are mutually correlated by supersymmetry requirement. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454365

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We study tachyon condensation in the noncommutative open string (NCOS) theory in the boundary string theory (BSFT) formalism. We explicitly construct an effective action for a tachyon including a gauge field. Based on our action, it is shown that there exists an electric flux tube at the vacuum of the tachyon. Its tension and positiveness suggest that after tachyon condensation we have a non-relativistic closed string (NRCS) proposed by Gomis and Ooguri. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454366

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

Tachyon condensation in a single unstable D-brane is discussed in the framework of boundary state formulation. The boundary state in the background of the tachyon condensation and the NSB-field is explicitly constructed. We show in both commutative theory and noncommutative theory that the unstable D-branes behaves like an extended object and eventually reduces to the lower dimensional D-branes as the system approaches the infrared fixed point. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454367

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

I present a conjectural matrix model for quantum gravity on four dimensional de Sitter space in this talk. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454368

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We study D0-brane quantum mechanics in the ’t Hooft large N limit and compare with supergravity using an analog of Maldacena duality introduced by Itzhaki &etal; To make the comparison at strong coupling, we develop a mean field approximation for quantum mechanics. We find agreement for the black hole entropy, and obtain the density of black hole microstates. By studying probe brane potentials, we reconstruct the spacetime metric from the large N quantum mechanics. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454369

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

The fact that both the D6-brane and the orientifold 6-plane have smooth, horizon-free descriptions in M-theory makes them especially useful in understanding certain aspects of brane physics. We briefly review how this connection has been used to understand a number of effects, several of which are associated with the Hanany-Witten transition. One particular outcome is a “confinement mod 2” effect for zero-branes in the background of a single D8-brane. We also discuss an interesting puzzle associated with flux-expulsion from D6-branes in this context. Finally, we discuss the promise of using a similar M-theoretic description of the orientifold 6-plane to understand the consistency of stringy negative energy objects with the 2nd law of black hole thermodynamics. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454370

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

The consistent form and the covariant form of the gauge anomaly for fundamentalU(N)chiral fermions on even-dimensional noncommutative space-time are computed and discussed. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454371

出版商:AIP    

年代:1902

数据来源: AIP