相关论文: Review of free-fermionic 4d string models
We discuss three closely related questions; i)~Given a conformal field theory, how may we deform it? ii)~What are the symmetries of string theory? and iii)~Does string theory have free parameters? We show that there is a distinct…
We study four dimensional field theory from the low-energy effective theory of Type I, II or heterotic string theories. Chiral fermions in four dimensions are obtained by several mechanisms. Especially, the background flux is one of the…
In string theory there seems to be an intimate connection between spacetime and world-sheet physics. Following this line of thought we investigate the family problem in a particular class of string solutions, namely the free fermionic…
We consider two questions in string ``phenomenology.'' First, are there any generic string predictions? Second, are there any general lessons which string theory suggests for thinking about low energy models, particularly in the framework…
We perform a systematic study of the Standard Model embedding in a D-brane configuration of type I string theory at the TeV scale. We end up with an attractive model and we study several phenomenological questions, such as gauge coupling…
Possible ways of constructing extended fermionic strings with $N=4$ world-sheet supersymmetry are reviewed. String theory constraints form, in general, a non-linear quasi(super)conformal algebra, and can have conformal dimensions $\geq 1$.…
Supersymmetry can be consistently generalized in one and two dimensional spaces, fractional supersymmetry being one of the possible extension. 2D fractional supersymmetry of arbitrary order $F$ is explicitly constructed using an adapted…
I outline a program to derive the Standard Model directly from superstring theory. I present a class of three generation superstring standard--like models in the free fermionic formulation. I discuss some phenomenological properties of…
New string dynamics is formulated on the basis of the extended set of supergauge constraints including not only supergauge Virasoro conditions but also nilpotent supercurrent constraints . This approach arises from a natural generalization…
We explore the use of real fermionization as a test case for understanding how specific features of phenomenological interest in the low-energy effective superpotential are realized in exact solutions to heterotic superstring theory. We…
Simple recursion relations for zero energy states of supersymmetric matrix models are derived by using an unconventional reducible representation for the fermionic degrees of freedom.
The existence of an extra Z' inspired from heterotic-string theory at accessible energy scales attracted considerable interest in the particle physics literature. Surprisingly, however, the construction of heterotic--string derived models…
Phenomenologically viable string vacua may require incorporating Kac-Moody algebras at level $\geq 2$. We exploit the free fermionic formulation to construct N=(0,2) world-sheet supersymmetric string models with specific phenomenological…
The mass scale of fundamental strings can be as low as few TeV/c^2 provided that spacetime extends into large extra dimensions. We discuss the phenomenological aspects of weakly coupled low mass string theory related to experimental…
We explicitly construct the states of the 2d free boson on the infinite line with specified asymptotic charges. The Minkowski CFT states derive from (the analytic continuation of) the shrinking limit of Euclidean angular quantization,…
In this paper we construct a $(2,2)$ dimensional string theory with manifest $N=1$ spacetime supersymmetry. We use Berkovits' approach of augmenting the spacetime supercoordinates by the conjugate momenta for the fermionic variables. The…
Recently it was demonstrated that free fermionic heterotic-strings can produce models with solely the Minimal Supersymmetric Standard Model states in the low energy spectrum. This unprecedented result provides further strong evidence for…
Supersymmetry breaking in string perturbation theory predicts the existence of a new dimension at the TeV scale. The simplest realization of the minimal supersymmetric Standard Model in the context of this mechanism has two important…
We use the free fermionic formulation of the heterotic-string in four dimensions to study the vacuum structure and energy of non-supersymmetric tachyon free models that correspond to compactifications of tachyonic vacua of the ten…
An approach towards a statistical survey of four dimensional supersymmetric vacua in the string theory landscape is described and illustrated with three examples of ensembles of intersecting D-brane models. The question whether it is…