# Cyclic Inflation

@article{Biswas2008CyclicI, title={Cyclic Inflation}, author={Tirthabir Biswas and Stephon H. S. Alexander}, journal={Physical Review D}, year={2008} }

We present an inflationary model that is geodesically complete and does not suffer from the transplanckian problem. In most inflationary models, massless (conformal) scalar field fluctuations in a deSitter background gives rise to a scale-invariant spectrum. In this work, we realize scale invariant perturbations from thermal fluctuations in (conformal) radiation during a radiation dominated contraction era prior to inflation. As the modes exit the Hubble radius during the contraction phase…

## 14 Citations

Towards the bounce inflationary gravitational wave

- Physics
- 2016

In the bounce inflation scenario, the inflation is singularity-free, while the advantages of inflation are preserved. We analytically calculate the power spectrum of its primordial gravitational…

Non-singular cosmology in a model of non-relativistic gravity

- Physics
- 2009

We present a model of non-relativistic gravitational theory which is power-counting renormalizable in 3+1 dimensional spacetime. When applied to cosmology, the relativity-violation terms lead to a…

Numerically Investigating the Emergent Cyclic Inflation Scenario

- Computer Science
- 2014

We provide a comprehensive numerical study of the emergent cyclic inflation scenario. This is a scenario where instead of traditional monotonic slow roll inflation, the universe expands over numerous…

Matter Bounce Cosmology with the f(T) Gravity

- Physics
- 2011

We show that the f(T) gravitational paradigm, in which gravity is described by an arbitrary function of the torsion scalar, can provide a mechanism for realizing bouncing cosmologies, thereby…

Cyclic cosmology from Lagrange-multiplier modified gravity

- Physics, Mathematics
- 2011

We investigate cyclic and singularity-free evolutions in a universe governed by Lagrange-multiplier modified gravity, in both scalar-field cosmology and the f(R) one. In the scalar case, cyclicity…

Towards a resolution of the cosmological singularity in non-local higher derivative theories of gravity

- Physics
- 2010

One of the greatest problems of standard cosmology is the Big Bang singularity. Previously it has been shown that non-local ghostfree higher-derivative modifications of Einstein gravity in the…

ISOTROPIZATION IN CHAPLYGIN MATTER UNIVERSES CONNECTED BY A WORMHOLE

- Physics
- 2013

Chaplygin anisotropic matter governing the cosmological evolution in two identical universes with an intermediate static spherically symmetric region is considered. The static region contains a…

Bounce and cyclic cosmology in weakly broken galileon theories

- Physics
- 2017

We investigate the bounce and cyclicity realization in the framework of weakly broken galileon theories. We study bouncing and cyclic solutions at the background level, reconstructing the potential…

Multi-scale gravity and cosmology

- Physics
- 2013

The gravitational dynamics and cosmological implications of three classes of recently introduced multi-scale spacetimes (with, respectively, ordinary, weighted and q- derivatives) are discussed.…

Thermal duality and Hagedorn transition from p-adic strings.

- MathematicsPhysical review letters
- 2010

We develop the finite temperature theory of p-adic string models. We find that the thermal properties of these nonlocal field theories can be interpreted either as contributions of standard thermal…

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