# Large N cosmology

@article{Brandenberger2004LargeNC, title={Large N cosmology}, author={Robert H. Brandenberger and P. M. Ho and H. C. Kao}, journal={Journal of Cosmology and Astroparticle Physics}, year={2004}, volume={2004}, pages={011-011} }

We motivate inflationary scenarios with many scalar fields, and give a complete formulation of adiabatic and entropy perturbations. We find that if the potential is very flat, or if the theory has a SO(N) symmetry, the calculation of the fluctuation spectrum can be carried out in terms of merely two variables without any further assumption. We do not have to assume slow roll or SO(N) invariance for the background fields. We give some examples to show that, even if the slow roll assumption holds…

## 25 Citations

Inflation in large N limit of supersymmetric gauge theories

- Physics
- 2004

Within supersymmetry we provide an example where the inflaton sector is derived from a gauge invariant polynomial of SU(N) or SO(N) gauge theory. Inflation in our model is driven by multi-flat…

On the number of Nflation fields

- Physics
- 2008

In this paper, we study the Nflation model, in which a collection of massive scalar fields drive the inflation, simultaneously. We observe that when the number of fields is larger than the square of…

Gauge-invariant inflaton in the minimal supersymmetric standard model.

- Physics, MedicinePhysical review letters
- 2006

We argue that all the necessary ingredients for successful inflation are present in the flat directions of the Minimally Supersymmetric Standard Model. We show that out of many gauge-invariant…

M-flation: inflation from matrix valued scalar fields

- Physics
- 2009

We propose an inflationary scenario, M-flation, in which inflation is driven by three N × N hermitian matrices Φi, i = 1, 2, 3. The inflation potential of our model, which is strongly motivated from…

Inflation in 6D gauged supergravity

- Physics
- 2004

In this note we demonstrate that chaotic inflation can naturally be realized in the context of an anomaly free minimal gauged supergravity in D = 6 which has recently been the focus of some…

Inflation From Matrix Valued Scalar Fields

- 2009

We propose an inflationary scenario, M-flation, in which inflation is driven by three N ×N hermitian matrices Φi, i = 1, 2, 3. The inflation potential of our model, which is strongly motivated from…

Inflection point inflation within supersymmetry

- Physics
- 2010

We propose to address the fine tuning problem of inflection point inflation by the addition of extra vacuum energy that is present during inflation but disappears afterwards. We show that in such a…

Inflation assisted by heterotic axions

- Physics
- 2007

We explore the possibility of obtaining inflation in weakly coupled heterotic string theory, where the model dependent axions are responsible for driving inflation. This model can be considered as a…

A-term inflation and the smallness of the neutrino masses

- Physics
- 2007

The smallness of the neutrino masses may be related to inflation. The minimal supersymmetric standard model (MSSM) with small neutrino Yukawa couplings already has all the necessary ingredients for a…

Old inflation in string theory

- Physics
- 2004

We propose a stringy version of the old inflation scenario which does not require any slow-roll inflaton potential and is based on a specific example of string compactification with warped metric.…

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