Introduction to Cosmology

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0.0 0.5 1.0

Simon9

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Figure 11.1Evidence for transition from deceleration in the past to acceleration today. From
reference [6]. From Farook, O. and Ratra, B., Hubble parameter measurement constraints
on the cosmological deceleration-acceleration transition redshift,Astrophys. J. Lett., 766 ,L7,
published 4 March 2013. © AAS. Reproduced with permission.