Accelerated Universe from Modified Chaplygin Gas and Tachyonic Fluid
نویسنده
چکیده
A cosmological model with an exotic fluid is investigated. We show that the equation of state of this “modified Chaplygin” gas can describe the current accelerated expansion of the universe. We then reexpress it as FRW cosmological model containing a scalar field φ and find its self–interacting potential. Moreover motivated by recent works of Sen [5, 6] and Padmanbhan [13] on tachyon field theory, a map for this exotic fluid as a normal scalar field φ with Lagrangian Lφ = φ̇ 2 2 − U(φ) to the tachyonic field T with Lagrangian LT = −V (T ) √
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