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On Generalized Chaplygin Gas. Yungui Gong 龚云贵 重庆邮电学院. 10/23/2004. 超弦 / 理论、粒子物理及宇宙学专题研讨会 10 月 21 日 -11 月 3 日. Motivation. Chaplygin gas. As a perfect fluid with the equation of state. Motivation: Nambu-Goto action for a d-brane moving in a
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On Generalized Chaplygin Gas Yungui Gong 龚云贵 重庆邮电学院 10/23/2004 超弦/理论、粒子物理及宇宙学专题研讨会10月21日-11月3日
Chaplygin gas As a perfect fluid with the equation of state Motivation: Nambu-Goto action for a d-brane moving in a (d+2)-dimensional spacetime in the light-cone parameterization Quintessence filed potential
Generalized Chaplygin Gas As a perfect fluid with the equation of state Quintessence filed potential Flat universe, Chaplygin gas is the only source
Cosmological Solution: Possible Unification of dark matter and dark energy
Constraints • The total energy density is non-negative • The current density is not increasing • Sound speed (1) (2) (3)
Constraints on GCG (1) (2) Used (1) (3) Used (1)
Physical Constraints From (2), we get
Current Measurements on matter density Peebles, PJE, astro-ph/0410284