arXiv subjects

Anirban Basu

Publications and source records attributed to Anirban Basu.

44 records · Page 3Linked to original sources

arXiv2005

The M2-M5 Brane System and a Generalized Nahm's Equation

We propose an equation that describes M2-branes ending on M5-branes, and which generalizes the description of the D1-D3 system via Nahm's equation. The simplest solution to this equation constructs the transverse geometry in terms of a fuzzy three sphere. We show that the solution passes a number of consistency checks including a consistent reduction to the D1-D3 system, a calculation of the energy of the system, matching to the self-dual string solution in the M5-brane world volume, and a study of simple fluctuations about the ground state configuration. We write down certain terms in the effective action of multiple membranes, which includes a sextic scalar coupling.

hep-th↗

arXiv2005

Boundary Ground Ring in Minimal String Theory

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.

hep-th↗

arXiv2004

A Curious Truncation of N=4 Yang-Mills

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 by using a truncated OPE expansion. This leads to differential equations for the coupling dependence. When applied to a particular sixteen point correlator, the coupling dependence we find agrees with the corresponding amplitude computed via the AdS/CFT correspondence. We conjecture that this truncation becomes exact in the large N and large 't Hooft coupling limit.

hep-th↗

arXiv2004

Some Systematics of the Coupling Constant Dependence of N=4 Yang-Mills

The operator, O_τ, 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 current Ward identities determine a class of terms in the operator product expansion of O_τwith any other operator. In certain cases, this leads to constraints on the coupling dependence of correlation functions in N=4 Yang-Mills. As an application, we demonstrate the exact non-renormalization of two and certain three-point correlation functions of BPS operators.

hep-th↗

arXiv2004

(0,2) Duality

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 defines an analogue of mirror symmetry for (0,2) theories. Using the dual description, we determine the instanton corrected chiral ring for some illustrative examples. This ring defines a (0,2) generalization of the quantum cohomology ring of (2,2) theories.

hep-th↗

arXiv2003

World-sheet Stability of (0,2) Linear Sigma Models

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. The general proof is based on the Konishi anomaly for (0,2) theories.

hep-th↗

arXiv2002

Localized Tachyons and the g_cl conjecture

We consider C/Z_N and C^2/Z_N orbifolds of heterotic string theories and Z_N orbifolds of AdS_3. We study theories with N=2 worldsheet superconformal invariance and construct RG flows. Following Harvey, Kutasov, Martinec and Moore, we compute g_cl and show that it decreases monotonically along RG flows- as conjectured by them. For the heterotic string theories, the gauge degrees of freedom do not contribute to the computation of g_cl.

hep-th↗

arXiv2000

Nonlocal Regularization For Non-Abelian Gauge Theories For Arbitrary Gauge Parameter

We study the nonlocal regularization for the non-abelian gauge theories for an arbitrary value of the gauge parameter (ξ). We show that the procedure for the nonlocalization of field theories established earlier by the original authors, when applied in that form to the Faddeev-Popov effective action in a linear gauge cannot lead to a (ξ)-independent result for the observables. We then show that an alternate procedure which is simpler can be used and that it leads to the S-matrix elements (where they exist) independent of (ξ).

hep-th↗