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Flipped SU(5) Predicts $δT/T$

Bumseok Kyae·Qaisar Shafi
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Abstract

We discuss hybrid inflation in supersymmetric flipped SU(5) model such that the cosmic microwave anisotropy $δT/T$ is essentially proportional to $(M /M_{P})^2$, where $M$ denotes the symmetry breaking scale and $M_{P}$ ($=2.4\times 10^{18}$ GeV) is the reduced Planck mass. The magnitude of $M$ determined from $δT/T$ measurements can be consistent with the value inferred from the evolution of SU(3) and SU(2) gauge couplings. In other words, one could state that flipped SU(5) predicts (more precisely `postdicts') $δT/T$. The scalar spectral index $n_s = 0.993\pm 0.007$, the scalar to tensor ratio satisfies $r \lapproxeq 10^{-6}$, while $dn_s/d{\rm ln}k \lapproxeq 4\times 10^{-4}$.

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Bumseok Kyae, Qaisar Shafi. 2006-03-06. Flipped SU(5) Predicts $δT/T$. https://doi.org/10.1016/j.physletb.2006.03.007

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