422 citations · 4.4k across the 133 of their papers we have counts for
26 papers · 1 filter
Comments on Brane Recombination, Finite Flux Vacua, and the Swampland
Jason Kumar, James D. Wells
The Swampland program relies heavily on the conjecture that there can only be a finite number of flux vacua (FFV conjecture). Stipulating this FFV conjecture and applying it to som…
Constructing Infrared Finite Propagators in Inflating Space-time
Jason Kumar, Louis Leblond, Arvind Rajaraman
The usual (Bunch-Davies) Feynman propagator of a massless field is not well defined in an expanding universe due to the presence of infrared divergences. We propose a new propagato…
A Toy Model for Gauge-Mediation in Intersecting Brane Models
Jason Kumar
We discuss the phenomenology of a toy intersecting brane model where supersymmetry is dynamically broken in an open string hidden sector and gauge-mediated to the visible sector. S…
Tachyon Mediated Non-Gaussianity
Bhaskar Dutta, Jason Kumar, Louis Leblond
We describe a general scenario where primordial non-Gaussian curvature perturbations are generated in models with extra scalar fields. The extra scalars communicate to the inflaton…
Intersecting Brane Models and Cosmology
Jason Kumar
We discuss the application of general features of intersecting brane model constructions in cosmology. In particular, we describe a scenario for D-term inflation which arises strai…
Dynamical SUSY Breaking in Intersecting Brane Models
Jason Kumar
We present a simple mechanism by which supersymmetry can be dynamically broken in intersecting brane models, naturally generating an exponentially small scale. Rather than utilize…
An Inflationary Scenario in Intersecting Brane Models
Bhaskar Dutta, Jason Kumar, Louis Leblond
We propose a new scenario for D-term inflation which appears quite straightforwardly in the open string sector of intersecting brane models. We take the inflaton to be a chiral fie…
Hidden Sector Baryogenesis
Bhaskar Dutta, Jason Kumar
We introduce a novel mechanism for baryogenesis, in which mixed anomalies between the hidden sector and drive the baryon asymmetry. We demonstrate that this mechani…
Multi-Brane Recombination and Standard Model Flux Vacua
Jason Kumar, James D. Wells
In a previous work, we noted that vacua with higher flux could be obtained by recombination of a small set of hidden-sector branes, numbering up to the Kahler degrees of freedom le…
A Review of Distributions on the String Landscape
Jason Kumar
We review some basic flux vacua counting techniques and results, focusing on the distributions of properties over different regions of the landscape of string vacua and assessing t…
Surveying Standard Model Flux Vacua on
Jason Kumar, James D. Wells
We consider the SU(2)LxSU(2)R Standard Model brane embedding in an orientifold of T6/Z2xZ2. Within defined limits, we construct all such Standard Model brane embeddings and determi…
High-Energy Scattering in Non-Commutative Field Theory
Jason Kumar, Arvind Rajaraman
We analyze high energy scattering for non-commutative field theories using the dual gravity description. We find that the Froissart-Martin bound still holds, but that cross-section…
Landscape Cartography: A Coarse Survey of Gauge Group Rank and Stabilization of the Proton
Jason Kumar, James D. Wells
The landscape of string/M theory is surveyed over a large class of type flux compactification vacua. We derive a simple formula for the average size of the gauge group rank o…
Revisiting D-branes in
Jason Kumar, Arvind Rajaraman
We find the most general supergravity solution in an background preserving an symmetry and half the supersymmetries. Contrary to previous expe…
Supergravity Solutions for branes
Jason Kumar, Arvind Rajaraman
We find a large class of supersymmetric solutions in the background with NS fluxes. This two-parameter family of solutions preserves 8 of the 16 supersymmetries…
New Supergravity Solutions for Branes in AdS_3 x S^3
Jason Kumar, Arvind Rajaraman
We find explicit supergravity solutions which describe branes in the AdS_3 x S^3 background. These solutions preserve 8 of the 16 supersymmetries of this background, and are consis…
A Brief Comment on Instanton-like Singularities and Cosmological Horizons
Jason Kumar
We argue that in the presence of instanton-like singularities, the existence of cosmological horizons can become frame-dependent, ie. a horizon which appears in Einstein frame may…
The Secret Gauging of Flavor Symmetries in Noncommutative QFT
Ken Intriligator, Jason Kumar
We show that flavor 't Hooft anomalies automatically vanish in noncommutative field theories which are obtained from string theory in the decoupling limit. We claim that this is be…
*-Wars Episode I: The Phantom Anomaly
Ken Intriligator, Jason Kumar
As pointed out, chiral non-commutative theories exist, and examples can be constructed via string theory. Gauge anomalies require the matter content of individual gauge group facto…
Comments on Unstable Branes
Ken Intriligator, Matt Kleban, Jason Kumar
We argue that type II string theories contain unstable NS4 branes, which descend from a conjectured unstable M4 brane of M-theory. Assuming that an M2 brane can arise in M5 brane/a…
Orientifolds, RG Flows, and Closed String Tachyons
Shamit Kachru, Jason Kumar, Eva Silverstein
We discuss the fate of certain tachyonic closed string theories from two perspectives. In both cases our approach involves studying directly configurations with finite negative tre…
Vacuum Energy Cancellation in a Non-supersymmetric String
Shamit Kachru, Jason Kumar, Eva Silverstein
We present a nonsupersymmetric orbifold of type II string theory and show that it has vanishing cosmological constant at the one and two loop level. We argue heuristically that the…
Black Holes and Superconformal Mechanics
P. Claus, M. Derix, R. Kallosh +3
The dynamics of a (super)particle near the horizon of an extreme Reissner-Nordstrom black hole is shown to be governed by an action that reduces to a (super)conformal mechanics mod…
Conformal Theory of M2, D3, M5 and `D1+D5' Branes
P. Claus, R. Kallosh, J. Kumar +2
The bosonic actions for M2, D3 and M5 branes in their own d-dimensional near-horizon background are given in a manifestly SO(p+1,2) x SO(d-p-1) invariant form (p=2,3,5). These symm…