Cosmic Microwave Background Anisotropy with Late Time Entropy Production
نویسندگان
چکیده
We discuss effects of cosmological moduli fields on the cosmic microwave background (CMB). If a modulus field φ once dominates the universe, the CMB we observe today is from the decay of φ and its anisotropy is affected by the primordial fluctuation in the amplitude of the modulus field. As a result, constraints on the inflaton potential from the CMB anisotropy can be relaxed. In addition, with the cosmological moduli fields, correlated mixture of adiabatic and isocurvature fluctuations may be generated, which results in enhanced CMB angular power spectrum at higher multipoles relative to that of lower ones. Such an enhancement can be an evidence of late time entropy production due to the cosmological moduli fields, and may be observed at on-going and future experiments. ∗ Talk given at the 5th RESCEU International Symposium on “New Trends in Theoretical and Observational Cosmology,” Tokyo, November 2001.
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