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...
Torsional Heterotic Geometries (2009)
Becker, Katrin, Sethi, Savdeep
We construct new examples of torsional heterotic backgrounds using duality with orientifold flux compactifications. We explain how duality provides a perturbative solution to the type I/heterotic...
Recursion Relations from Space-time Supersymmetry (2008)
We describe a method for obtaining relations between higher derivative interactions in supersymmetric effective actions. The method extends to all orders in the momentum expansion. As an application,...
Half-Twisted (0,2) Landau-Ginzburg Models (2007)
Melnikov, Ilarion V., Sethi, Savdeep
We compute correlators of chiral operators in (0,2) supersymmetric Landau-Ginzburg theories. The class of theories and the correlators we study are relevant for extending and testing mirror symmetry...
A Note on Heterotic Dualities via M-theory (2007)
We show that a class of torsional compactifications of the heterotic string are dual to conventional Kahler heterotic string compactifications. This observation follows from the recently proposed...
Instantons, Hypermultiplets and the Heterotic String (2007)
Halmagyi, Nick, Melnikov, Ilarion V., Sethi, Savdeep
Hypermultiplet couplings in type IIA string theory on a Calabi-Yau space can be quantum corrected by D2-brane instantons wrapping special Lagrangian cycles. On the other hand, hypermultiplet...
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...
Effective Dynamics of the Matrix Big Bang (2006)
Craps, Ben, Rajaraman, Arvind, Sethi, Savdeep
We study the leading quantum effects in the recently introduced Matrix Big Bang model. This amounts to a study of supersymmetric Yang-Mills theory compactified on the Milne orbifold. We find a...
A Matrix Model for the Null-Brane (2005)
Robbins, Daniel, Sethi, Savdeep
The null-brane background is a simple smooth 1/2 BPS solution of string theory. By tuning a parameter, this background develops a big crunch/big bang type singularity. We construct the DLCQ...
Craps, Ben, Sethi, Savdeep, Verlinde, Erik
The light-like linear dilaton background represents a particularly simple time-dependent 1/2 BPS solution of critical type IIA superstring theory in ten dimensions. Its lift to M-theory, as well as...
A Curious Truncation of N=4 Yang-Mills (2004)
Basu, Anirban, Green, Michael B., Sethi, Savdeep
The coupling constant dependence of correlation functions of BPS operators in N=4 Yang-Mills can be expressed in terms of integrated correlation functions. We approximate these integrated correlators...
Some Systematics of the Coupling Constant Dependence of N=4 Yang-Mills (2004)
Basu, Anirban, Green, Michael B., Sethi, Savdeep
The operator, O_\tau, that generates infinitesimal changes of the coupling constant in N=4 Yang-Mills sits in the same supermultiplet as the superconformal currents. We show how superconformal...
Robbins, Daniel, Sethi, Savdeep
We consider the generation of a non-perturbative superpotential in F-theory compactifications with flux. We derive a necessary condition for the generation of such a superpotential in F-theory. For...
Structure in Supersymmetric Yang-Mills Theory (2004)
We show that requiring sixteen supersymmetries in quantum mechanical gauge theory implies the existence of a web of constrained interactions. Contrary to conventional wisdom, these constraints extend...
Adams, Allan, Basu, Anirban, Sethi, Savdeep
We construct dual descriptions of (0,2) gauged linear sigma models. In some cases, the dual is a (0,2) Landau-Ginzburg theory, while in other cases, it is a non-linear sigma model. The duality map...
Adams, Allan, Basu, Anirban, Sethi, Savdeep
We construct dual descriptions of (0, 2) gauged linear sigma models. In some cases, the dual is a (0, 2) Landau-Ginzburg theory, while in other cases, it is a non-linear sigma model. The duality map...
The UV/IR Interplay in Theories with Space-time Varying Non-commutativity (2003)
Robbins, Daniel, Sethi, Savdeep
We consider scalar field theory with space and space-time-dependent non-commutativity. In perturbation theory, we find that the structure of the UV/IR mixing is quite different from cases with...
World-sheet Stability of (0,2) Linear Sigma Models (2003)
We argue that two-dimensional (0,2) gauged linear sigma models are not destabilized by instanton generated world-sheet superpotentials. We construct several examples where we show this to be true....
Time-Dependent Warping, Fluxes, and NCYM (2003)
Dasgupta, Keshav, Rajesh, Govindan, Robbins, Daniel, Sethi, Savdeep
We describe the supergravity solutions dual to D6-branes with both time-dependent and time-independent B-fields. These backgrounds generalize the Taub-NUT metric in two key ways: they have asymmetric...
Holography and String Dynamics in Time-dependent Backgrounds (2002)
Hashimoto, Akikazu, Sethi, Savdeep
We study the dynamics of D-branes in a smooth time-dependent background. The theory on the branes is a time-dependent non-commutative field theory. We find the metric and fluxes that determine the...
Twisting E8 Five-Branes (2002)
Keurentjes, Arjan, Sethi, Savdeep
We consider the tensor theory on coincident E8 5-branes compactified on a three torus. Using string theory, we predict that there must be distinct components in the moduli space of this theory.We...
Non-commutativity and Supersymmetry (2002)
Paban, Sonia, Sethi, Savdeep, Stern, Mark
We study the extent to which the gauge symmetry of abelian Yang-Mills can be deformed under two conditions: first, that the deformation depend on a two-form scale. Second, that the deformation...
Novel Type I Compactifications (2001)
Morrison, David R., Sethi, Savdeep
We argue that there are two distinct classes of type I compactification to four dimensions on any space. These two classes are distinguished in a mysterious way by the presence (or absence) of a...
Triples, Fluxes, and Strings (2001)
De Boer, Jan, Dijkgraaf, Robbert, Hori, Kentaro, Keurentjes, Arjan, Morgan, John, Morrison, David R., ...
We study string compactifications with sixteen supersymmetries. The moduli space for these compactifications becomes quite intricate in lower dimensions, partly because there are many different...
Saltatory Relaxation of the Cosmological Constant (2000)
Feng, Jonathan L., March-Russell, John, Sethi, Savdeep, Wilczek, Frank
We modify and extend an earlier proposal by Brown and Teitelboim to relax the effective cosmological term by nucleation of branes coupled to a three-index gauge potential. Microscopic considerations...
Duality and Non-Commutative Gauge Theory (2000)
Ganor, Ori J., Rajesh, Govindan, Sethi, Savdeep
We study the generalization of S-duality to non-commutative gauge theories. For rank one theories, we obtain the leading terms of the dual theory by Legendre transforming the Lagrangian of the...
The Structure of the D0-D4 Bound State (2000)
We derive a set of equations for the wavefunction describing the marginal bound state of a single D0-brane with a single D4-brane. These are equations determining the vacuum of an N=8 abelian gauge...
Invariance Theorems for Supersymmetric Yang-Mills Theories (2000)
We consider quantum mechanical Yang-Mills theories with eight supercharges and a $Spin(5) \times SU(2)_R$ flavor symmetry. We show that all normalizable ground states in these gauge theories are...
M Theory, Orientifolds and G-Flux (1999)
Dasgupta, Keshav, Rajesh, Govindan, Sethi, Savdeep
We study the properties of M and F theory compactifications to three and four dimensions with background fluxes. We provide a simple construction of supersymmetric vacua, including some with...
Supersymmetry and the Yang-Mills Effective Action at Finite N (1999)
We study the effective action of quantum mechanical SU(N) Yang-Mills theories with sixteen supersymmetries and N>2. We show that supersymmetry requires that the eight fermion terms in the...
A Relation Between N=8 Gauge Theories in Three Dimensions (1998)
We show that three-dimensional N=8 $Sp(N)$ and $SO(2N+1)$ gauge theories flow to the same strong coupling fixed point. As a consequence, the corresponding orientifold two-planes in type IIA string...
Summing Up Instantons in Three-Dimensional Yang-Mills Theories (1998)
Paban, Sonia, Sethi, Savdeep, Stern, Mark
We show that the four derivative terms in the effective action of three-dimensional N=8 Yang-Mills theory are determined by supersymmetry. These terms receive both perturbative and non-perturbative...
Supersymmetry Constraints on Type IIB Supergravity (1998)
Green, Michael B., Sethi, Savdeep
Supersymmetry is used to derive conditions on higher derivative terms in the effective action of type IIB supergravity. Using these conditions, we are able to prove earlier conjectures that certain...
Supersymmetry and Higher Derivative Terms in the Effective Action of Yang-Mills Theories (1998)
Paban, Sonia, Sethi, Savdeep, Stern, Mark
Higher derivative terms in the effective action of certain Yang-Mills theories can be severely constrained by supersymmetry. We show that requiring sixteen supersymmetries in quantum mechanical gauge...
Constraints From Extended Supersymmetry in Quantum Mechanics (1998)
Paban, Sonia, Sethi, Savdeep, Stern, Mark
We consider quantum mechanical gauge theories with sixteen supersymmetries. The Hamiltonians or Lagrangians characterizing these theories can contain higher derivative terms. In the operator...
The Higgs Branch of Impurity Theories (1998)
Kapustin, Anton, Sethi, Savdeep
We consider supersymmetric gauge theories with impurities in various dimensions. These systems arise in the study of intersecting branes. Unlike conventional gauge theories, the Higgs branch of an...
Geometric Realizations of BPS States in N=2 Theories (1998)
Mikhailov, Andrei, Nekrasov, Nikita, Sethi, Savdeep
We study the BPS spectrum of the theory on a D3-brane probe in F theory. The BPS states are realized by multi-string configurations in spacetime. Only certain configurations obeying a selection rule...
New Perspectives on Yang-Mills Theories With Sixteen Supersymmetries (1997)
We describe various approaches that give matrix descriptions of compactified NS five-branes. As a result, we obtain matrix models for Yang-Mills theories with sixteen supersymmetries in dimensions...
The Matrix Formulation of Type IIB Five-Branes (1997)
We present a matrix model which interpolates between type IIA and type IIB NS five-branes. The matrix description involves a three-dimensional bulk quantum field theory interacting with impurities...
Comments on Neveu-Schwarz Five-Branes (1997)
Seiberg, Nathan, Sethi, Savdeep
We study the theory of NS five-branes in string theory with a smooth non-trivial transverse space. We show that in the limit that the bulk physics decouples, these theories become equivalent to...
D-Brane Bound States Redux (1997)
We study the existence of D-brane bound states at threshold in Type II string theories. In a number of situations, we can reduce the question of existence to quadrature, and the study of a particular...
The Mirror Transform of Type I Vacua in Six Dimensions (1997)
We study certain compactifications of the type I string on K3. The three topologically distinct choices of gauge bundle for the type I theory are shown to be equivalent to type IIB orientifolds with...
Rotational Invariance in the M(atrix) Formulation of Type IIB Theory (1997)
Sethi, Savdeep, Susskind, Leonard
The matrix model formulation of M-theory can be generalized by compactification to ten-dimensional type II string theory, formulated in the infinite momentum frame. Both the type IIA and IIB string...
On Orbifolds of (0,2) Models (1996)
Blumenhagen, Ralph, Sethi, Savdeep
We study orbifolds of (0,2) models, including some cases with discrete torsion. Our emphasis is on models which have a Landau-Ginzburg realization, where we describe part of the massless spectrum by...