CORRECTIONS TO STANDARD RADIATION DOMINATED UNIVERSE IN JORDAN-BRANS-DICKE COSMOLOGY

Arik M., SUSAM L.

ROMANIAN REPORTS IN PHYSICS, cilt.73, sa.2, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 73 Sayı: 2
  • Basım Tarihi: 2021
  • Dergi Adı: ROMANIAN REPORTS IN PHYSICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, INSPEC, zbMATH
  • Anahtar Kelimeler: Jordan-Brans-Dicke, scalar-tensor theory of gravity, BROKEN-SYMMETRIC THEORY, SCALAR-TENSOR THEORY, MACHS PRINCIPLE, DARK ENERGY, GRAVITY, NUCLEOSYNTHESIS, PERTURBATIONS, EQUATION, STRINGS, SIGN
  • İstanbul Üniversitesi Adresli: Evet

Özet

Brans-Dicke theory in its original form can explain the radiation and matter dominated eras with a constant Brans-Dicke scalar field and the explanation of dark energy requires a nonvanishing potential term for the scalar field in the action. Within the framework of Jordan-Brans-Dicke theory where we take the scalar field as the Jordan field with a standard kinetic term and no mass term, we find the same radiation dominated solution as given by Einstein cosmology. On the other hand, by adding a mass term for the scalar field to the action, the radiation dominated solution is modified. We make an expansion in increasing powers of the scale size. This is valid for small scale sizes. We show that this expansion describing the early radiation dominated era also gives the late time dark energy dominated era in the Friedmann equation.