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Fate of thermal log type Q balls
Takeshi Chiba, Kohei Kamada, Shinta Kasuya +1
We study time evolution of the ball in thermal logarithmic potential using lattice simulations. As the temperature decreases due to the cosmic expansion, the thermal logarithmi…
Time variation of proton-electron mass ratio and fine structure constant with runaway dilaton
Takeshi Chiba, Tatsuo Kobayashi, Masahide Yamaguchi +1
Recent astrophysical observations indicate that the proton-electron mass ratio and the fine structure constant have gone through nontrivial time evolution. We discuss their time va…
Baryogenesis in a flat direction with neither baryon nor lepton charge
Takeshi Chiba, Fuminobu Takahashi, Masahide Yamaguchi
We present a new mechanism of spontaneous baryogenesis. Usually such mechanisms require a derivative coupling between a scalar field and baryon current. In our model, the scalar fi…
Quintessence Cosmology and Varying
Takeshi Chiba, Kazunori Kohri
If the reported measurements of the time variation of the fine structure constant from observations of distant QSOs are correct, combined with the Oklo limit they would strongly co…
Extended Open Inflation
Takeshi Chiba, Masahide Yamaguchi
We present a new type of one-field models for open inflation utilizing a nonminimally coupled scalar field with polynomial potentials in which the Coleman-de Luccia instanton does…