Gauge fields-strings duality and tensionless superstrings (original) (raw)

Tensionless strings, correspondence with sigma-model

Physics Letters B, 2005

String theory with perimeter action is tensionless by its geometrical nature and has pure massless spectrum of higher spin gauge particles. I demonstrate that liner transformation of the world-sheet fields defines a map to the SO(D,D) sigma model equipped by additional Abelian constraint, which breaks SO(D,D) to a diagonal SO(1,D-1). The effective tension is equal to the square of the dimensional coupling constant of the perimeter action. This correspondence allows to view the perimeter action as a "square root" of the Nambu-Goto area action. The aforementioned map between tensionless strings and SO(D,D) sigma model allows to introduce the vertex operators in full analogy with the standard string theory and to confirm the form of the vertex operators introduced earlier.

The Zero tension limit of strings and superstrings

1993

The string equivalent of a massless particle ($m=0$) is the tensionless string ($T=0$). The study of such strings is of interest when trying to understand the high energy limit of ordinary strings. I discuss the classical Tto0T\to 0Tto0 limit of the bosonic string, the spinning string and the superstring. A common feature is the appearence of a space-time (super-)conformal symmetry replacing the world-sheet Weyl invariance. The question of whether this symmetry may survive quantization is addressed. A lightcone analysis of the quantized bosonic tensionless string leads to severe constraints on the physical states: they are space-time diffeomorphism singlets characterized by their topological properties only.

The String Tension in Two-Dimensional Gauge Theories

International Journal of Modern Physics A, 1999

We review and elaborate on properties of the string tension in two-dimensional gauge theories. The first model we consider is massive QED in the m≪e limit. We evaluate the leading string tension both in the fermionic and bosonized descriptions. We discuss the next-to-leading corrections in m/e. The next-to-leading terms in the long distance behavior of the quark–antiquark potential, are evaluated in a certain region of external versus dynamical charges. The finite temperature behavior is also determined. In QCD 2 we review the results for the string tension of quarks in cases with dynamical quarks in the fundamental, adjoint, symmetric and antisymmetric representations. The screening nature of SYM 2 is re-derived.

Doubly supersymmetric null strings and string tension generation

Physics Letters B, 1993

We propose a twistor-like formulation of N=1, D=3,4,6 and 10 null superstrings. The model possesses N=1 target space supersymmetry and n=D-2 local worldsheet supersymmetry, the latter replaces the κ-symmetry of the conventional approach to the strings. Adding a Wess-Zumino term to a null superstring action we observe a string tension generation mechanism [1, 2]: the induced worldsheet metric becomes nondegenerate and the resulting model turns out to be classically equivalent to the heterotic string. †

Gauge dyonic strings and their global limit

Nuclear Physics B, 1998

We show that six-dimensional supergravity coupled to tensor and Yang-Mills multiplets admits not one but two different theories as global limits, one of which was previously thought not to arise as a global limit and the other of which is new. The new theory has the virtue that it admits a global anti-self-dual string solution obtained as the limit of the curved-space gauge dyonic string, and can, in particular, describe tensionless strings. We speculate that this global model can also represent the worldvolume theory of coincident branes. We also discuss the Bogomol'nyi bounds of the gauge dyonic string and show that, contrary to expectations, zero eigenvalues of the Bogomol'nyi matrix do not lead to enhanced supersymmetry and that negative tension does not necessarily imply a naked singularity.

Classical and quantized tensionless strings

Nuclear Physics B411 (1994) 122—156

From the ordinary tensile string we derive a geometric action for the tensionless (T = 0) string and discuss its symmetries and field equations. The Weyl symmetry of the usual string is shown to be replaced by a global space—time conformal symmetry in the T — 0 limit. We present the explicit expressions for the generators of this group in the light-cone gauge. Using these, we quantize the theory in an operator form and require the conformal symmetry to remain a symmetry of the quantum theory. Modulo details concerning zero-modes that are discussed in the paper, this leads to the stringent restriction that the physical states should be singlets under space—time diffeomorphisms, hinting at a topological theory. We present the details of the calculation that leads to this conclusion.

Self-dual strings and N = 2 supersymmetric field theory

Nuclear Physics B, 1996

We show how the Riemann surface of N = 2 Yang-Mills eld theory arises in type II string compactications on Calabi-Yau threefolds. The relevant local geometry is given by brations of ALE spaces. The 3-branes that give rise to BPS multiplets in the string descend to self-dual strings on the Riemann surface, with tension determined by a canonically xed Seiberg-Witten dierential . This gives, eectively, a dual formulation of Yang-Mills theory in which gauge bosons and monopoles are treated on equal footing, and represents the rigid analog of type II-heterotic string duality. The existence of BPS states is essentially reduced to a geodesic problem on the Riemann surface with metric jj 2 . This allows us, in particular, to easily determine the spectrum of stable BPS states in eld theory.

On the Gauge/Gravity Correspondence and the Open/Closed String Duality

International Journal of Modern Physics A, 2005

In this paper we review the conditions for the validity of the gauge/gravity correspondence in both supersymmetric and nonsupersymmetric string models. We start by reminding what happens in type IIB theory on the orbifolds ℂ2/ℤ2 and ℂ3/(ℤ2 x ℤ2), where this correspondence beautifully works. In these cases, by performing a complete stringy calculation of the interaction among D3-branes, it has been shown that the fact that this correspondence works is a consequence of the open/closed duality and of the absence of threshold corrections. Then we review the construction of type 0 theories with their orbifolds and orientifolds having spectra free from both open and closed string tachyons and for such models we study the validity of the gauge/gravity correspondence, concluding that this is not a peculiarity of supersymmetric theories, but it may work also for nonsupersymmetric models. Also in these cases, when it works, it is again a consequence of the open/closed string duality and of va...