Related papers: Rolling Closed String Tachyons and the Big Crunch
Rolling tachyon backgrounds, arising from open strings on unstable branes in bosonic string theory, can be related to a simple statistical mechanical model - Coulomb gas of point charges in two dimensions confined to a circle, the Dyson…
The rolling tachyon is a non-canonical scalar field model well motivated in string theory which naturally predicts variations of the fine-structure constant. Such variations can in principle lead to interesting observable consequences, but…
A weak-field solution of Einstein's equations is constructed. It is generated by a circular cosmic string revolving in its plane about the centre of the circle. (The revolution is introduced to prevent the string from collapsing.) This…
Brane cosmology driven by the tachyon rolling down to its ground state is investigated. We adopt an effective field theoretical description for the tachyon and Randall-Sundrum type brane world scenario. After formulating basic equations, we…
We propose a framework where the string scale as well as all compact dimensions are at the electroweak scale $\sim$ TeV$^{-1}$. The weakness of gravity is attributed to the small value of the string coupling $g_s \sim 10^{-16}$, presumably…
We conjecture that the end point of bulk closed string tachyon decay at any non-zero coupling, is the annihilation of space time by Witten's bubble of nothing, resulting in a topological phase of the theory. In support of this we present a…
We study classical solutions of a low energy effective theory of a string theory with tachyons. With a certain ansatz, we obtain all possible solutions which are weakly coupled and weakly curved. We find, in addition to the interpolating…
We present a characterization of a bosonic field theory driven by a free (Gaussian) tachyonic Hamiltonian. This regime is obtained from a theory describing two coupled bosonic fields after a regular quench. Relevant physical quantities such…
A recent paper by Gross and Erler (hep-th/0406199) showed that by making a certain well-defined, unitary transformation on the mode basis for the open bosonic string--one that identifies the lightcone component of position with the string…
A basic problem in gravitational physics is the resolution of spacetime singularities where general relativity breaks down. The simplest such singularities are conical singularities arising from orbifold identifications of flat space, and…
In this review we describe our current understanding of the properties of open string tachyons on an unstable D-brane or brane-antibrane system in string theory. The various string theoretic methods used for this study include techniques of…
The first massive level of closed bosonic string theory is studied. Free-field equations are derived by imposing Weyl invariance on the world sheet. A two-parameter solution to the equation of motion and constraints is found in two…
We discuss the problem of tachyon condensation in the framework of background independent open string field theory. We show, in particular, that the computation of the string field theory action simplifies considerably if one looks at…
The C/Z_N orbifold of type II string theory has localized tachyons with m^2 ranging from -1+1/N to -2/N in units of 2/\alpha'. We show that by restricting attention to the lightest tachyons it is possible to take a zero-slope limit where N…
We show that $4$-dimensional Robertson-Walker spacetimes can be constructed for which all of the beta functions vanish to leading order, yielding consistent string theory without extra dimensions. We find that there is a unique static…
We study certain supersymmetry breaking deformations of linear dilaton backgrounds in different dimensions. In some cases, the deformed theory has bulk closed strings tachyons. In other cases there are no bulk tachyons, but there are…
We compute the one-loop partition function for quadratic tachyon background in open string theory. Both closed and open string representations are developed. Using these representations we study the one-loop divergences in the partition…
We show an explicit relation between an RG flow of a two-dimensional gravity and an on-shell tachyon condensation in the corresponding string theory, in the case when the string theory is supercritical. The shape of the tachyon potential in…
Four-dimensional homogeneous static and rotating black strings in dynamical Chern-Simons modified gravity, with and without torsion, are presented. Each solution is supported by a scalar field that depends linearly on the coordinate that…
We consider the gravitational field of infinite straight and stationary twisted Baby Skyrmion cosmic string. Using the approximate solution of Einstein equations, it is shown that the internal phase rotation (twist) along the string axis is…