2013/07/24 by Hyerim Noh, Jai-chan Hwang
Physics and Astronomy · #Black Holes and Theoretical Physics #Classical mechanics #Cosmological constant #Cosmological perturbation theory #Cosmology #Cosmology and Gravitation Theories #Dark energy #Einstein #Galaxies: Formation, Evolution, Phenomena #Gauge (firearms) #Inflation (cosmology) #Lambda-CDM model #Newtonian fluid #Nonlinear system #Perfect Cosmological Principle #Perfect fluid #Perturbation (astronomy) #Perturbation theory (quantum mechanics) #Physics #Quantum mechanics #Theoretical physics #astro-ph.CO #gr-qc
paper · pdf · doi:10.1088/1475-7516/2013/08/040
16 pages, no figure
arxiv created 2013/07/24 · openalex publication_date 2013/08/21 · arxiv updated 2015/06/16 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We derive the basic equations of the cosmological first-order post-Newtonian approximation from the recently formulated fully nonlinear and exact cosmological perturbation theory in Einstein's gravity. Apparently the latter, being exact, should include the former, and here we use this fact as a new derivation of the former. The complete sets of equations in both approaches are presented without fixing the temporal gauge conditions so that we can use the gauge choice as an advantage. Comparisons between the two approaches are made. Both are potentially important in handling relativistic aspects of nonlinear processes occurring in cosmological structure formation. We consider an ideal fluid and include the cosmological constant.