Non-Supersymmetric String Theory (2009)
Martinec, Emil J., Robbins, Daniel, Sethi, Savdeep
A class of non-supersymmetric string backgrounds can be constructed using twists that involve space-time fermion parity. We propose a non-perturbative definition of string theory in these backgrounds...
Martinec, Emil J., Robbins, Daniel, Sethi, Savdeep
The null-brane space-time provides a simple model of a big crunch/big bang singularity. A non-perturbative definition of M-theory on this space-time was recently provided using matrix theory. We...
Boundary Ground Ring in Minimal String Theory (2005)
Basu, Anirban, Martinec, Emil J.
We obtain relations among boundary states in bosonic minimal open string theory using the boundary ground ring. We also obtain a difference equation that boundary correlators must satisfy.
Matrix Models and 2D String Theory (2004)
String theory in two-dimensional spacetime illuminates two main threads of recent development in string theory: (1) Open/closed string duality, and (2) Tachyon condensation. In two dimensions, many...
The Annular Report on Non-Critical String Theory (2003)
Recent results on the annulus partition function in Liouville field theory are applied to non-critical string theory, both below and above the critical dimension. Liouville gravity coupled to $c\le...
Closed String Tachyon Condensation and Worldsheet Inflation (2003)
Da Cunha, Bruno Carneiro, Martinec, Emil J.
Closed string tachyon condensation in spacetime generates potentials on the worldsheet that model two-dimensional inflationary cosmology. These models illustrate and elucidate a variety of aspects of...
Martinec, Emil J., Moore, Gregory
Closed string tachyon condensation resolves the singularities of nonsupersymmetric orbifolds, however the resolved space typically has fewer D-brane charges than that of the orbifold. The description...
Defects, Decay, and Dissipated States (2002)
The worldsheet renormalization group approach to tachyon condensation in string theory is reviewed. The open string case is summarized with examples, and closed string tachyon condensation on...
Martinec, Emil J., McElgin, Will
The supersymmetric $(AdS_3\times S^3)/Z_N$ orbifold constructed by the authors in hep-th/0106171 is shown to describe AdS fragmentation, where fivebranes are emerging from the F1-NS5 background. The...
Localized Tachyons and RG Flows (2001)
Harvey, Jeffrey A., Kutasov, David, Martinec, Emil J., Moore, Gregory
We study condensation of closed string tachyons living on defects, such as orbifold fixed planes and Neveu-Schwarz fivebranes. We argue that the high energy density of localized states decreases in...
Noncommutative Solitons on Orbifolds (2001)
Martinec, Emil J., Moore, Gregory
In the noncommutative field theory of open strings in a B-field, D-branes arise as solitons described as projection operators or partial isometries in a $C^*$ algebra. We discuss how D-branes on...
D-branes and Strings as Non-commutative Solitons (2000)
Harvey, Jeffrey A., Kraus, Per, Larsen, Finn, Martinec, Emil J.
The non-commutative geometry of a large auxiliary $B$-field simplifies the construction of D-branes as solitons in open string field theory. Similarly, fundamental strings are constructed as...
Black holes and the phases of brane thermodynamics (1999)
Introductory lectures on the relations between the thermodynamics of gauge theory on branes and black holes, including the correspondence principle of Horowitz and Polchinski, the AdS/CFT conjecture,...
Conformal Field Theory, Geometry, and Entropy (1998)
In the context of the AdS/CFT correspondence, an explicit relation between the physical degrees of freedom of 2+1d gravity and the stress tensor of 1+1d conformal field theory is exhibited. Gravity...
Matrix Models of AdS Gravity (1998)
We explore the connection between anti-deSitter supergravity and gauge theory, in the context of bound states of many D1 and D5 branes. The near-horizon $AdS_3$ supergravity describes the identity...
Comments on Black Holes in Matrix Theory (1997)
Horowitz, Gary T., Martinec, Emil J.
The recent suggestion that the entropy of Schwarzschild black holes can be computed in matrix theory using near-extremal D-brane thermodynamics is examined. It is found that the regime in which this...