arXiv subjects

Bobby S. Acharya

Publications and source records attributed to Bobby S. Acharya.

21 records · Page 2Linked to original sources

arXiv2005

Statistics of M theory Vacua

We study the vacuum statistics of ensembles of M theory compactifications on G_2 holonomy manifolds with fluxes, and of ensembles of Freund-Rubin vacua. We discuss similarities and differences between these and Type IIB flux landscapes. For the G_2 ensembles, we find that large volumes are strongly suppressed, and for both, unlike the IIB case, the distribution of cosmological constants is non-uniform. We also argue that these ensembles typically have exponentially more non-supersymmetric than supersymmetric vacua, and show that supersymmetry is virtually always broken at a high scale.

hep-th↗

arXiv2004

M theory and Singularities of Exceptional Holonomy Manifolds

M theory compactifications on G_2 holonomy manifolds, whilst supersymmetric, require singularities in order to obtain non-Abelian gauge groups, chiral fermions and other properties necessary for a realistic model of particle physics. We review recent progress in understanding the physics of such singularities. Our main aim is to describe the techniques which have been used to develop our understanding of M theory physics near these singularities. In parallel, we also describe similar sorts of singularities in Spin(7) holonomy manifolds which correspond to the properties of three dimensional field theories. As an application, we review how various aspects of strongly coupled gauge theories, such as confinement, mass gap and non-perturbative phase transitions may be given a simple explanation in M theory.

hep-th↗

arXiv2001

Fivebranes Wrapped On Associative Three-Cycles

We construct supergravity solutions corresponding to fivebranes wrapping associative three-cycles of constant curvature in manifolds of G_2-holonomy. The solutions preserve 2 supercharges and are first constructed in D=7 gauged supergravity and then lifted to D=10,11. We show that the low-energy theory of M-fivebranes wrapped on a compact hyperbolic three-space is dual to a superconformal field theory in D=3 by exhibiting a flow to an AdS_4 region. For IIB-fivebranes wrapped on a three-sphere we speculate on a connection with spontaneous supersymmetry breaking of pure N=1 super Yang-Mills theory in D=3.

hep-th↗