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Title: Modified teleparallel gravity: Inflation without an inflaton

Abstract

The Born-Infeld strategy to smooth theories having divergent solutions is applied to the teleparallel equivalent of general relativity. Differing from other theories of modified gravity, modified teleparallelism leads to second order equations, since the teleparallel Lagrangian only contains first derivatives of the vierbein. We show that the Born-Infeld-modified teleparallelism solves the particle horizon problem in a spatially flat Friedmann-Robertson-Walker (FRW) universe by providing an initial exponential expansion without resorting to an inflaton field.

Authors:
 [1];  [2];  [1]
  1. Instituto de Astronomia y Fisica del Espacio, Casilla de Correo 67, Sucursal 28, 1428 Buenos Aires (Argentina)
  2. (Argentina)
Publication Date:
OSTI Identifier:
21020400
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 8; Other Information: DOI: 10.1103/PhysRevD.75.084031; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BORN-INFELD THEORY; COSMOLOGY; FIELD EQUATIONS; GENERAL RELATIVITY THEORY; GRAVITATION; INFLATIONARY UNIVERSE; LAGRANGIAN FUNCTION; MATHEMATICAL SOLUTIONS; UNIVERSE

Citation Formats

Ferraro, Rafael, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires, and Fiorini, Franco. Modified teleparallel gravity: Inflation without an inflaton. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.084031.
Ferraro, Rafael, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires, & Fiorini, Franco. Modified teleparallel gravity: Inflation without an inflaton. United States. doi:10.1103/PHYSREVD.75.084031.
Ferraro, Rafael, Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires, and Fiorini, Franco. Sun . "Modified teleparallel gravity: Inflation without an inflaton". United States. doi:10.1103/PHYSREVD.75.084031.
@article{osti_21020400,
title = {Modified teleparallel gravity: Inflation without an inflaton},
author = {Ferraro, Rafael and Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria, Pabellon I, 1428 Buenos Aires and Fiorini, Franco},
abstractNote = {The Born-Infeld strategy to smooth theories having divergent solutions is applied to the teleparallel equivalent of general relativity. Differing from other theories of modified gravity, modified teleparallelism leads to second order equations, since the teleparallel Lagrangian only contains first derivatives of the vierbein. We show that the Born-Infeld-modified teleparallelism solves the particle horizon problem in a spatially flat Friedmann-Robertson-Walker (FRW) universe by providing an initial exponential expansion without resorting to an inflaton field.},
doi = {10.1103/PHYSREVD.75.084031},
journal = {Physical Review. D, Particles Fields},
number = 8,
volume = 75,
place = {United States},
year = {Sun Apr 15 00:00:00 EDT 2007},
month = {Sun Apr 15 00:00:00 EDT 2007}
}
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