The multi-loop interaction amplitudes of the closed, oriented superstring are given by finite dimensional integrals of explicit expressions where the integrations are performed over super-Schottky group parameters and over the coordinates of the interaction vertices on the supermanifold. It is shown the amplitudes are free from divergences. The vanishing of the vacuum amplitude and other fundamental properties of the amplitudes are verified. The results can be extended to other superstring theories including Dirichlet boundary conditions. Thus for applications of the superstring perturbation series rich opportunities are opened.
Authors:G. Danilov
Proposed speaker: G. Danilov
Contact person:Guennadi S. Danilov
(Petersburg Nuclear Physics Institute),
danilov@thd.pnpi.spb.ru
Sessions: PA-16 Superstring Theory /
Supporting papers:
Notes:In the calculation the explicit integration measures and the superfield correlators are used, which have been given in the papers: 1. G.S. Danilov, Calculation of Feynman diagrams in superstring perturbation theory. Physical Review D51: 4359-4386, 1995. [ Erratum-inbid. D52, p. 6201, 1995]. 2. G.S. Danilov, Unimodular transformations of the supermanifolds and the calculation of the multi-loop amplitudes in the superstring theory. Nuclear Physics B 463: 443-486, 1996.
Recent results on the Wilson loop operator in N=4 Super Yang Mills theory and other related gauge theories will be discussed. Non-perturbative computations using the AdS/CFT correspondence and perturbative results will be reported. Comments on the compatibility of the strong coupling ansatz with the Migdal-Makeenko loop equations as well as the realization of conformal symmetry will be presented.
Authors:Gordon W. Semenoff
Proposed speaker: Gordon W. Semenoff
Contact person:Gordon W. Semenoff
(University of British Columbia),
semenoff@physics.ubc.ca
Sessions: PA-16 Superstring Theory / PL-10 Recent Progress in Field Theory
Supporting papers:
Notes:
Four dimensional gauge theories can be consistently expressed as a five dimensional theory that turns out to be a renormalizable topological quantum field theory. This considerably simplifies conceptual questions such as for instance the Gribov phenomenon and the definition of chiral fermions on the lattice. We refine the definition of the symmetries in the five dimensional framework, and indicate how observables can be selected. We explain the way chirality is defined in this formulation and detail the five-dimensional mechanism of anomalies.
Authors:l. Baulieu and D. Zwanziger
Proposed speaker: L. Baulieu
Contact person:L. Baulieu
(),
baulieu@lpthe.jussieu.fr
Sessions: PA-16 Superstring Theory /
Supporting papers:
Notes:6/20/00 TY-Baulieu had convener as the contact person. Fixed.
The problem of obtaining the genus expansion of perturbative IIA superstring theory from the matrix model of M-theory is addressed. Discrete light cone quantization of strings on a (finite temperature) Z2 orbifild is discussed. An explicit characterization of the worldsheets which contribute to the string path integral for any genus is found. These worldsheets are shown to be branched covers of a particular torus. Their relationship with instantons in matrix string theory and further aspects of producing superstring perturbation theory in the context of matrix theory are examined.
Authors:Gordon W. Semenoff
Proposed speaker: Gordon W. Semenoff
Contact person:Gordon W. Semenoff
(University of British Columbia),
semenoff@physics.ubc.ca
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: Paper: hep-th/0004194 From: Lori D. Paniak <paniak@feynman.princeton.edu> Title: Matrix Theory Interpretation of DLCQ String Worldsheets Authors: G. Grignani, P. Orland, L. D. Paniak and G. W. Semenoff Comments: 9 pages LaTeX Report-no: IASSNS-HEP-00/35, NSF-ITP-00-36, PUPT-1927 G. Grignani and G. W. Semenoff, Nucl. Phys. B561, 243 (1999).
Notes:
Extending the seminal work of Bilal/Gervais, we construct a tachyon-free, modular invariant partition function for typeII strings on a conifold. We directly deal with N=2, c=9 unitary superconformal characters associated with SL(2,R)/U(1). It describes a critical superstring on 4d Minkowski space times 2d black hole. Modular invariance is achieved by requiring the string to have a momentum along the cigar. The 4d massless spectrum coincides with that of the tensionless strings, being in agreement with the proposal of Bershadsky et.al. on the dual description of typeII strings on a conifold in terms of two intersecting NS5-branes.
Authors:Shun'ya Mizoguchi
Proposed speaker: Shun'ya Mizoguchi
Contact person:Shun'ya Mizougchi
(Institute of Particle and Nuclear Studies, KEK),
shunya.mizoguchi@kek.jp
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: MODULAR INVARIANT CRITICAL SUPERSTRINGS ON FOUR-DIMENSIONAL MINKOWSKI SPACE TIMES TWO-DIMENSIONAL BLACK HOLE. By Shun'ya Mizoguchi (KEK, Tsukuba). KEK-PREPRINT-99-189, Mar 2000. 18pp. Published in 0004:014,2000 e-Print Archive: hep-th/0003053
Notes:
The perturbative aspects of ultraviolet and infrared dynamics of such a theory is examined in detail. It is observed that the high loop momemtum contribution to the nonplanar diagram develops the infrared singularity with respect to the external momentum. The degree of such a singularity is intimately associated with that of the ultraviolet divergence of planar diagram. It is also shown that such a relation is precise in noncommutative Yang-Mills theory, but the same feature does not persist in noncommutative generalization of QED.
Authors:Masashi Hayakawa
Proposed speaker: Masashi Hayakawa
Contact person:Masashi Hayakawa
(KEK),
haya@post.kek.jp
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: M. Hayakawa, ``Perturbative analysis on infrared aspects of noncommutative QED on R**4,'' Phys. Lett. B478}, 394 (2000), hep-th/9912094. M. Hayakawa, ``Perturbative analysis on infrared and ultraviolet aspects of noncommutative QED on R**4'', hep-th/9912167.
Notes:
The perturbative aspects of ultraviolet and infrared dynamics of such a theory is examined in detail. It is observed that the high loop momemtum contribution to the nonplanar diagram develops the infrared singularity with respect to the external momentum. The degree of such a singularity is intimately associated with that of the ultraviolet divergence of planar diagram. It is also shown that such a relation is precise in noncommutative Yang-Mills theory, but the same feature does not persist in noncommutative generalization of QED.
Authors:Masashi Hayakawa
Proposed speaker: Masashi Hayakawa
Contact person:Masashi Hayakawa
(KEK),
haya@post.kek.jp
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: M. Hayakawa, ``Perturbative analysis on infrared aspects of noncommutative QED on R**4,'' Phys. Lett. B478}, 394 (2000), hep-th/9912094. M. Hayakawa, ``Perturbative analysis on infrared and ultraviolet aspects of noncommutative QED on R**4'', hep-th/9912167.
Notes:
We propose a scenario in which there is one millimeter size(R) and five TEV^-1 size (r)extra dimensions with the SM gauge bosons propagating into only one of r size dimensions. A new scaling relation involving 4-dimensional M_Planck, M_string, R and r works with M_strin around 100 Tev. Stringent astrophysical constraints from supernova 1987A, and CDRGB are well satisfied in this scenario. In addition to new gravitational force at the millimeter scale, the scenario will test string dynamics at the LHC and NLC energies via the enhanced high p_T multijet productions as well as top productions at LHC, and enhanced Higgs and photon productions at the NLC.
Authors:J. Lykken, C. McMullen and S. Nandi
Proposed speaker: S. Nandi
Contact person:Satyanarayan Nandi
(Oklahoma State University),
shaown@okstate.edu
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: Asymmetrical large extra dimensions, J. Lykken and S. Nandi, hep-ph/9908505. Gauge coupling unification with large extra dimensions, D. Dumitru and S. Nandi, hep-ph/9906514 ( to appear in Phys. Rev. D, in press ). Collider probe of the Kaluza-Klein excitations of gauge bosons, C. McMullen, and S. Nandi ( to appear ).
Notes:I will also briefly review the related works in symmetrical scenarios, and also the case in which only gravity sees the extra dimensions.
We consider open strings ending on D-branes in the presence of constant metric, $G_{ij}$, and antisymmetric tensor, $B_{ij}$. The Hamiltonian is expressed in a form analogous to the one derived for toroidally compactified closed string which has manifestly "$O(d,d)$" invariant form. The evolution equation of string coordinates $\{ X^i \}$ are considered in the first order formalism and a set of 'dual' coordinates $\{Y_i \}$ are introduced and their evolution equations are derived. It is shown that starting from mixed boundary condition for one set of coordinates, we can go over to dual coordinates which satisfy only Neumann boundary conditions. In other words, the former theory is endowed with noncommutative string coordinates whereas the coordinates of the latter theory are commutative. An explicit example is presented where, starting from nonzero G and vanishing B, one can go over to a configuration of nonvanishing G and B by implementing an infinitesimal "O(d,d)" transformation.
Authors:Jnanadeva Maharana and Shesansu S. Pal
Proposed speaker: Jnanadeva Maharana
Contact person:John H Schwarz
(),
jhs@theory.caltech.edu
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers:
Notes:
Area-Preserving diffeomorphisms are often approximated by large classical groups, though the precise nature of the approximation is often unclear and dependent on the precise way in the way in which limits are taken. In this paper we examine the global issues rigorously, and clarify the nature of the various limiting procedures. The results have important implications for matrix and membrane theories, and are suggestive of how one might describe topology change within such theories.
Authors:J.D. Swain
Proposed speaker: J. D. Swain
Contact person:John D Swain
(Northeastern University),
john.swain@cern.ch
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: There is a huge literature (which I will cite) but here are a couple of representative papers: B. de Wit, J. Hoppe, H. Nicolai, ON THE QUANTUM MECHANICS OF SUPERMEMBRANES, Nucl.Phys.B305:545,1988 J. Hoppe, P. Schaller (Karlsruhe U.). INFINITELY MANY VERSIONS OF SU(INFINITY), Phys.Lett.B237:407-410,1990
Notes:
It is well known that type I critical string theories are consistent for some restricted gauge symmetries in the Chan-Paton method, such as SO(32), E(8)*E(8) for superstrings, SO(8192) for bosonic strings. The consistency yields the one-loop cancellation of divergences in the planar and Mobius amplitudes. In this talk, we show that the type I non-critical string field theory in the 2-dimensional target space is consistent only for SO(2) symmetry by constructing it from a matirx model wchich describes the c=1 conformal matter on 2D random surfaces.
Authors:Hiroshi Kawabe and Naohito Nakazawa
Proposed speaker: Hiroshi Kawabe
Contact person:Naohito Nakazawa
(Shimane Univ.),
nakazawa@riko.shimane-u.ac.jp
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers:
Notes:This work is an extended version of our previous papers in PLB417(98)247 and PLB454(99)43.
We study properties of (D$(p-2)$, D$p$) nonthreshold bound states ($2 \le p \le 6 $) in the dual gravity description. We find that in the decoupling limit, the thermodynamics of the $N_p$ coincident D$p$-branes with $B$ field is the same not only as that of $N_p$ coincident D$p$-branes without $B$ field, but also as that of the $N_{p-2}$ coincident D$(p-2)$-branes with two smeared coordinates and no $B$ field, for $N_{p-2}/N_p= \tilde{V}_2/[(2\pi)^2 \tilde{b}]$ with $\tilde{V}_2$ being the area of the two smeared directions and $\tilde{b}$ a noncommutativity parameter. This suggests that the noncommutative super Yang-Mills with gauge group $U(N_p)$ in ($p+1$) dimensions is equivalent to an ordinary one with gauge group $U(\infty)$ in ($p-1$) dimensions in the limit $\tilde{V}_2 \to \infty$.
Authors:Rong-Gen Cai and Nobuyoshi Ohta
Proposed speaker: Cai, Rong-Gen
Contact person:Ron-Gen Cai
(Osaka Univ.),
cai@het.phys.sci.osaka-u.ac.jp
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: hep-th/9910092 hep-th/0001213
Notes:
Using AdS/CFT correspondence we found the conformal anomaly from three- and five-dimensional gauged supergravity with single scalar(dilaton) and the arbitrary scalar potential on AdS like background. This dilaton-dependent conformal anomaly corresponds to two- and four-dimensional dual quantum field theory which is classically conformal invariant. The candidate c-functions from supergravity are suggested. These c-functions which have fixed points in asymptotically AdS region are expressed in terms of dilatonic potential and they are positively defined and monotonic for a number of potentials.
Authors:Shin'ichi Nojiri, Sergei D. Odintsov, Sachiko Ogushi.
Proposed speaker: Sachiko Ogushi
Contact person:Sachiko Ogushi
(Ochanomizu Univ.),
g9970503@edu.cc.ocha.ac.jp
Sessions: PA-16 Superstring Theory /
Supporting papers:
Notes:This talk is based on the works, hep-th/9912191 and hep-th/0001122. (033)
We consider open strings ending on D-branes in the presence of constant metric, G, antisymmetric tensor, B and gauge field, A. The Hamiltonian is is manifestly invariant under a global noncompact group; strikingly similar to toroidally compactified closed string Hamiltonian. The evolution equations for the string coordinates, $\{X^i \}$ and their dual partners, $\{Y_i \}$, are combined to obtain equations of motion invariant under the noncompact transformations. We show that one can start from a noncommutative theory, with nonvanishing G and B and mixed boundary conditions and then go over to a dual theory whose coordinates obey Dirichlet boundary conditions.
Authors:Jnanadeva Maharana Shesansu S. Pal
Proposed speaker: Jnanadeva Maharana
Contact person:John H Schwarz
(CALTECH),
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: Noncommutative Open strings, D-brane and Duality
Notes:
We study the dynamics of D-branes in the near-horizon geometry of NS five branes. This leads to a hollographically dual description of the phyiscs of D-branes ending on and/or intersecting NS5-branes. We use it to verify some properties of such D-branes which were deduced indirectly in the past and discuss some instabilities of non-supersymmetric brane configurations. Our construction also describes vacua of Little String Theory which are dual to open plus closed string theory in asymptotically linear spacetimes.
Authors:Eliezer Rabinovici, S. Elitzur, A. Giveon, D. Kutasov and
G. Sarkissian
Proposed speaker: Eliezer Rabinovici
Contact person:Eliezer Rabinovici
(),
eliezer@vms.huji.ac.il
Sessions: PA-16 Superstring Theory / PL-13 Superstring Theory
Supporting papers: hep-th/0005052
Notes:6/10/00 TY-Late submission through Higashijima.
End of abstracts for PA-16 Superstring Theory