說明 
151 p 
附註 
Source: Dissertation Abstracts International, Volume: 6802, Section: B, page: 1039 

Adviser: Andrew Strominger 

Thesis (Ph.D.)Harvard University, 2007 

This thesis has three parts. In the first, we study the DasJevicki collective field description of arbitrary classical solutions in the c = 1 matrix model, which are believed to describe nontrivial spacetime backgrounds in 2D string theory. Our analysis naturally includes the case of a Fermi droplet cosmology. We cast the droplet collective field theory in standard coordinates and comment on the form of the interactions 

In the second part, we prove the existence of topological rings in (0, 2) theories containing nonanomalous leftmoving U(1) currents by which they may be twisted. While the twisted models are not topological, their ground operators form a ring under nonsingular OPE which reduces to the (a,c) or (c,c) ring at (2, 2) points and define a quantum sheaf cohomology. In the special case of CalabiYau compactifications, these rings are shown to exist globally on the moduli space in many cases 

In the third part, we construct worldsheet descriptions of heterotic flux vacua as the IR limits of N = 2 gauge theories. Spacetime torsion is incorporated via a 2D GreenSchwarz mechanism in which a doublet of axions cancels a oneloop gauge anomaly. Manifest (0, 2) supersymmetry and the compactness of the gauge theory instanton moduli space suggest that these models, which include FuYau models, are stable against worldsheet instantons 

School code: 0084 

DDC 
Host Item 
Dissertation Abstracts International 6802B

主題 
Physics, Elementary Particles and High Energy


0798

Alt Author 
Harvard University

