Cosmological Models with Linearly Varying Deceleration Parameter

Akarsu O., Dereli T.

INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS, cilt.51, sa.2, ss.612-621, 2012 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 51 Sayı: 2
  • Basım Tarihi: 2012
  • Doi Numarası: 10.1007/s10773-011-0941-5
  • Dergi Adı: INTERNATIONAL JOURNAL OF THEORETICAL PHYSICS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.612-621
  • Anahtar Kelimeler: Cosmological solutions, Variable deceleration parameter, Accelerating universe, Dark energy, Big rip, COSMIC ACCELERATION, DARK ENERGY, CONSTRAINTS, DYNAMICS
  • İstanbul Teknik Üniversitesi Adresli: Hayır

Özet

We propose a new law for the deceleration parameter that varies linearly with time and covers Berman's law where it is constant. Our law not only allows one to generalize many exact solutions that were obtained assuming constant deceleration parameter, but also gives a better fit with data (from SNIa, BAO and CMB), particularly concerning the late time behavior of the universe. According to our law only the spatially closed and flat universes are allowed; in both cases the cosmological fluid we obtain exhibits quintom like behavior and the universe ends with a big-rip. This is a result consistent with recent cosmological observations.