28.11.2012 Views

Exact Solutions and Scalar Fields in Gravity - Instituto Avanzado de ...

Exact Solutions and Scalar Fields in Gravity - Instituto Avanzado de ...

Exact Solutions and Scalar Fields in Gravity - Instituto Avanzado de ...

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

REVISITING THE CALCULATION OF<br />

INFLATIONARY PERTURBATIONS.<br />

Cèsar A. Terrero–Escalante<br />

Departamento <strong>de</strong> Física,<br />

Centro <strong>de</strong> Investigatión y <strong>de</strong> Estudios <strong>Avanzado</strong>s <strong>de</strong>l IPN,<br />

Apdo. Postal 14–740, 07000, México, D.F., México.<br />

Dom<strong>in</strong>ik J. Schwarz<br />

Institut für Theoretische Physik, TU-Wien,<br />

Wiedner Hauptstrass e 8–10, A–1040 Wien, Austria.<br />

Alberto Garcia<br />

Departamento <strong>de</strong> Física,<br />

Centro <strong>de</strong> Investigación y <strong>de</strong> Estudios <strong>Avanzado</strong>s <strong>de</strong>l IPN,<br />

Apdo. Postal 14–740, 07000, México, D.F., México.<br />

Abstract We present a new approximation scheme that allows us to <strong>in</strong>crease the<br />

accuracy of analytical predictions of the power spectra of <strong>in</strong>flationary<br />

perturbations for two specific classes of <strong>in</strong>flationary mo<strong>de</strong>ls. Among<br />

these mo<strong>de</strong>ls are chaotic <strong>in</strong>flation with a monomial potential, power–<br />

law <strong>in</strong>flation <strong>and</strong> natural <strong>in</strong>flation (<strong>in</strong>flation at a maximum). After<br />

review<strong>in</strong>g the established first or<strong>de</strong>r results we calculate the amplitu<strong>de</strong>s<br />

<strong>and</strong> spectral <strong>in</strong>dices for these classes of mo<strong>de</strong>ls at next or<strong>de</strong>r <strong>in</strong> the<br />

slow–roll parameters for scalar <strong>and</strong> tensor perturbations.<br />

1. INTRODUCTION<br />

Inflationary cosmology [1] is fac<strong>in</strong>g excit<strong>in</strong>g times due to a new generation<br />

of ground <strong>and</strong> satellite based experiments to be carried out (e.g.,<br />

the SDSS, MAP <strong>and</strong> Planck experiments [2]). Upcom<strong>in</strong>g observations<br />

will allow us to <strong>de</strong>term<strong>in</strong>e the values of the cosmological parameters<br />

with high confi<strong>de</strong>nce. To measure the values of these parameters it is<br />

necessary to make assumptions on the <strong>in</strong>itial conditions of the <strong>de</strong>nsity<br />

<strong>Exact</strong> <strong>Solutions</strong> <strong>and</strong> <strong>Scalar</strong> <strong>Fields</strong> <strong>in</strong> <strong>Gravity</strong>: Recent Developments<br />

Edited by Macias et al., Kluwer Aca<strong>de</strong>mic/Plenum Publishers, New York, 2001 235

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!