Space-time curvature and the cosmic horizon: derivations using the Newtonian world and the Friedmann-Robertson-Walker metric

ÖZTAŞ A. M., Smith M. L.

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, cilt.449, sa.2, ss.1270-1274, 2015 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 449 Sayı: 2
  • Basım Tarihi: 2015
  • Doi Numarası: 10.1093/mnras/stv346
  • Dergi Adı: MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.1270-1274
  • Anahtar Kelimeler: supernovae: general, cosmological parameters, distance scale, HUBBLE CONSTANT, IA SUPERNOVAE, CT UNIVERSE, R-H, MODELS
  • Hacettepe Üniversitesi Adresli: Evet

Özet

Several relationships describing the distance versus time dependence of the cosmic horizon (R-h) for an expanding universe have been published within the past two decades. Some are based on the special conditions, including a flat universe geometry, and when applied for calculation return significantly different values. We present our derivation beginning with Newtonian world then following the Friedmann model from the viewpoint of an observer located at the origin of an expanding spherical, homogeneously matter-dominated universe; both geometrically flat and allowing space-time curvature. Our derivations for the cosmic horizon at the speed of light allow examination for the effects of matter density and space-time curvature. We also compare the fitness of several current models, including the recently proposed R-h = ct universe against the demands of the 580 Union 2.1 Type Ia supernovae distance and redshift data with uncommon, proper attention paid to data transformation and observational errors.