3 research outputs found
Supersymmetric non-abelian Born-Infeld theory
Using the natural curvature invariants as building blocks in a superfield construction, we show that the use of a symmetric trace is mandatory if one is to reproduce the square root structure of the non-Abelian Dirac-Born-Infeld Lagrangian in the bosonic sector. We also discuss the BPS relations in connection with our supersymmetry construction.Facultad de Ciencias Exacta
Primordial fluctuations from nonlinear couplings
We study the spectrum of primordial fluctuations in theories where the
inflaton field is coupled to massless fields and/or to itself. Conformally
invariant theories generically predict a scale invariant spectrum. Scales
entering the theory through infrared divergences cause logarithmic corrections
to the spectrum, tiltilng it towards the blue. We discuss in some detail
whether these fluctuations are quantum or classical in nature.Comment: 12 pages, Revtex, we added an appendix clarifying our assumptions
about the initial conditions at the beggining of inflatio