摘要:

We considered the identity projector of the star product algebra of the open string field theory. We confirmed that the trace is identified with the D-brane tension. We proposed that the purely cubic theory may be one of the good candidates to describe the vacuum string field theory. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454392

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We investigate the AdS/CFT correspondence for higher-derivative gravity systems and develop a formalism in which the generating functional of the boundary field theory is given as a functional that depends only on the boundary values of bulk fields. We also derive a Hamilton-Jacobi-like equation that uniquely determines the generating functional, and give an algorithm calculating the Weyl anomaly. Using the expected duality between a higher-derivative gravity system andN=2superconformal field theory in four dimensions, we demonstrate that the resulting Weyl anomaly is consistent with the field theoretic anomaly. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454393

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We analyze how lower-dimensional bosonic D-branes further decay, using the boundary string field theory. Especially we find that the effective tachyon potential of the lower-dimensional D-brane has the same profile as that of D25-brane. The poster is based on the collaboration with S. Nakamura [1]. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454394

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

The nature of the cosmological constant has been one of the important problems in physics. On the other hand, the topological defects produced by various cosmological phase transitions consist of false vacuum energy. They may provide an effective cosmological constant. In this contribution, the interactions of such defects with the particles are investigated and the resulting detection possibility of cosmological vacuum energy density will be discussed. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454395

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We propose a basic strategy to obtain a consistent on-shell effective action of open-string tachyons, on the background where closed-string tachyons are already condensed. We use sigma-model approach, basically. We regard D-instanton-like objects with appropriate weight as closed-string tachyon tadpoles, and we insert them into worldsheets to analyze the effect of closed-string tachyons. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454396

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We show that the spherical D2-brane inSU(2)WZW model can be well described as the “fuzzy sphere” configuration of D0-branes. We further investigate the stability of some configurations of D0-branes in NS5 background. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454397

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We discuss higher derivative bulk gravity (without Riemann tensor square term) admits AdS-Schwarzschild black hole as exact solution. Higher derivative terms contributions appear in the entropy and energy via the redefinition of 5-dimensional gravitational constant and AdS scale parameter. These higher derivative terms do not destroy the AdS-dual description of radiation represented by strongly-coupled CFT. Cardy-Verlinde formula which expresses cosmological entropy as square root from other parameters is derived inR2-gravity. This report is based on the works with Shin’ichi Nojiri and Sergei D. Odintsov [1]. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454398

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We classify supersymmetricD0-Dpbound states with a non-zeroB-field by considering T-dualities of intersecting branes at angles. Especially, we find that the D0-D8 system with theB-field preserves 1/16, 1/8 and 3/16 of supercharges if theB-field satisfies the “(anti-)self-dual” condition in dimension eight. The D0-branes in this system are described by eight dimensional instantons on non-commutativeR8.We also discuss the extended ADHM construction of the eight-dimensional instantons and its deformation by theB-field. The modified ADHM equations admit a sort of the “fuzzy sphere” (embedding ofSU(2)) solution. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454399

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We study marginal stability of BPS states in four-dimensionalN=2theories withENglobal symmetry. We use the D3-brane probe realization where BPS states correspond to string webs in the affineEN7-brane background. We construct string webs involving loops and find a transition between a loop string web and an open string. The transition describes a new phenomenon occurring on marginal stability curves. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454400

出版商:AIP    

年代:1902

数据来源: AIP

摘要:

We study the cosmological evolution of a D3-brane Universe in a type 0 string background. We follow the brane universe along the radial coordinate of the background and we calculate the energy density which is induced on the brane because of its motion in the bulk. For constant values of tachyon and dilaton an inflationary phase is appearing. For non constant values of tachyon and dilaton and for a particular range of values of the scale factor of the brane-universe, the effective energy density is dominated by a term proportional to1/(log&hthinsp;&agr;)4indicating a slowly varying inflationary phase. ©2002 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1454401

出版商:AIP    

年代:1902

数据来源: AIP