Related papers: Noncommutative Tachyons and K-Theory
We investigate non-commutativity of open strings, attached to a D$p$-brane, in the presence of the linear dilaton, tachyon, U(1) gauge field as well as constant anti-symmetric $B$-field backgrounds. Non-commutativity parameter, open string…
It has been conjectured that a pair of D5 - anti D5 branes wrapped on some non-trivial two cycle of a Calabi-Yau manifold becomes a stable BPS D3 brane in the presence of a very large B field and magnetic fluxes on their worldvolumes. We…
We review how to describe the stable non-BPS D-branes of type II string theory from a classical perspective, and discuss the properties of the space-time geometry associated to these configurations. This is relevant in order to see whether…
By using the non-supersymmetric $p$-brane solutions delocalized in arbitrary number of transverse directions in type II supergravities, we show how they can be regarded as interpolating solutions between unstable D$p$-branes (a non-BPS…
Extending previous work that involved D3-branes ending on a fivebrane with $\theta_{\mathrm{YM}}\not=0$, we consider a similar two-sided problem. This construction, in case the fivebrane is of NS type, is associated to the three-dimensional…
We propose a way to identify the gauge invariant operator in noncommutative gauge theory on a D-brane with nonzero B field which couples to a specific supergravity mode in the bulk. This uses the description of noncommutative gauge theories…
It has recently been argued that D-branes in bosonic string theory can be described as noncommutative solitons, outside whose core the tachyon is condensed to its ground state. We conjecture that, in addition, the local U(1) gauge symmetry…
We show how the T-duality is realized for D-branes with noncommutative world-volume coordinates. We discuss D-branes wrapped on tori and the result is that the recently found noncommutative actions form a consistent collection due to the…
We show that the transformation of D-branes under T-duality on four-torus is represented by Nahm transform of instantons. The argument for this allows us to generalize Nahm transform to the case of orthogonal and symplectic gauge groups as…
In this paper we discuss the boson/vortex duality by mapping the (3+1)D Gross-Pitaevskii theory into an effective string theory in the presence of boundaries. Via the effective string theory, we find the Seiberg-Witten map between the…
General spinning brane bound states are constructed, along with their near-horizon limits which are relevant as dual descriptions of non-commutative field theories. For the spinning D-brane world volume theories with a B-field a general…
This is an expository paper which aims at explaining a physical point of view on the K-theoretic classification of D-branes. We combine ideas of renormalization group flows between boundary conformal field theories, together with spacetime…
D0-branes on a D2-brane with a constant background B-field are unstable due to the presence of a tachyonic mode and expected to dissolve into the D2-brane to formulate a constant D0-charge density. In this paper we study such a dissolution…
In this short note we formulate Covariant Hamiltonian formalism for strings, p-branes and Non-BPS Dp-branes. We also analyse the vacuum tachyon condensation in case of unstable D1-brane.
We give a general construction of extended moduli spaces of topological D-branes as non-commutative algebraic varieties. This shows that noncommutative symplectic geometry in the sense of Kontsevich arises naturally in String Theory.
Superstring theory has continued to develop at a rapid clip in the past few years. Following a quick review of some of the major discoveries prior to 1998, this talk focuses on a few of the more recent developments. The topics I have chosen…
RR fluxes representing different cohomology classes may correspond to the same twisted K-theory class. We argue that such fluxes are related by monodromies, generalizing and sometimes T-dual to the familiar monodromies of a D7-brane. A…
We consider tachyon condensation between a D-brane and an anti-D-brane in superstring theory, when they are separated in their common transverse directions. A simple rolling tachyon solution, that describes the time evolution of the…
We construct new exact BPS solitons in various noncommutative gauge theories by the ``gauge'' transformation of known BPS solitons. This ``gauge'' transformation introduced by Harvey, Kraus and Larsen adds localized solitons to the known…
We find a class of exact solutions of noncommutative gauge theories corresponding to unstable non-BPS solitons. In the two-dimensional euclidean (or 2+1 dimensional lorentzian) U(1) theory we find localized solutions carrying nonzero…