Gravity waves goodbye

J. P. Zibin; Douglas Scott; Martin White

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arXiv · astro-ph/9904228

Gravity waves goodbye

J. P. Zibin·Douglas Scott·Martin White

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Abstract

The detection of a stochastic background of long-wavelength gravitational waves (tensors) in the cosmic microwave background (CMB) anisotropy would be an invaluable probe of the high energy physics of the early universe. Unfortunately a combination of factors now makes such a detection seem unlikely: the vast majority of the CMB signal appears to come from density perturbations (scalars) - detailed fits to current observations indicate a tensor-to-scalar quadrupole ratio of T/S < 0.5 for the simplest models; and on the theoretical side the best-motivated inflationary models seem to require very small T/S. Unfortunately CMB temperature anisotropies can only probe a gravity wave signal down to T/S \sim 10% and optimistic assumptions about polarization of the CMB only lower this another order of magnitude.

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J. P. Zibin, Douglas Scott, Martin White. 1999-04-18. Gravity waves goodbye. https://arxiv.org/abs/astro-ph/9904228

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