Cosmological Constant from the Emergent Gravity Perspective

摘要: Observations indicate that our universe is characterized by a late-time accelerating phase, possibly driven cosmological constant $\Lambda$, with the dimensionless parameter $\Lambda L_P^2 \simeq 10^{-122}$, where $L_P = (G \hbar /c^3)^{1/2}$ Planck length. In this review, we describe how emergent gravity paradigm provides new insight and possible solution to problem. After reviewing necessary background material, identify sufficient conditions for solving We show these are naturally satisfied in which (i) field equations of invariant under addition matter Lagrangian (ii) appears as an integration solution. The numerical value can be related another number (called CosMIn) counts modes inside Hubble volume cross radius during radiation dominated epochs universe. suggests CosMIn has $4 \pi$, which, turn, leads correct, observed constant. Further, alternative perspective on cosmology interprets expansion itself quest towards holographic equipartition. discuss implications novel alternate description cosmology.