Observational Diagnostics of a Parametrized Deceleration Parameter in FLRW Cosmology

Shukla B. K., SOFUOĞLU D., Beesham A., Tiwari R. K., Msweli M. S.

Particles, cilt.9, sa.2, 2026 (ESCI, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 9 Sayı: 2
  • Basım Tarihi: 2026
  • Doi Numarası: 10.3390/particles9020041
  • Dergi Adı: Particles
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), Scopus, Aerospace Database, Applied Science & Technology Source, INSPEC, Directory of Open Access Journals, Technology Collection (ProQuest)
  • Anahtar Kelimeler: dark energy, late time acceleration of universe, observational analysis, parameterization of deceleration parameter
  • İstanbul Üniversitesi Adresli: Evet

Özet

The evolution of the deceleration parameter (Formula presented.) plays a crucial role in understanding the dynamics of dark energy within the framework of modern cosmology. In this study, we perform a parametric reconstruction of (Formula presented.) in a spatially flat Friedmann–Robertson–Walker (FLRW) Universe composed of radiation, pressureless dark matter, and dark energy. We consider a physically motivated form of (Formula presented.) that effectively describes the transition of the Universe from a decelerating to an accelerating expansion phase. This parametrization is incorporated into the Friedmann equations to derive the corresponding Hubble parameter, which is then confronted with a comprehensive set of observational data, including Hubble parameter measurements (Formula presented.), Type Ia supernovae (SNIa), and Baryon Acoustic Oscillations (BAO) data. Employing the Markov Chain Monte Carlo (MCMC) approach, we constrain the model parameters using the combined (Formula presented.) dataset. The best-fit parameters are subsequently used to reconstruct the cosmographic quantities, such as the deceleration, jerk, and snap parameters, which provide deeper insight into the expansion history of the Universe. Finally, a comparative analysis with the standard (Formula presented.) CDM model is carried out to assess the compatibility and effectiveness of the proposed parametrization.