Answer Happy

Posted: **Sun May 15, 2022 8:35 pm**

: Critical Universe Redshift Consider A Critical Universe Nm 1 Without Dark Energy 121 0 And A Local Hubble Constant 1 (29.94 KiB) Viewed 46 times

: Critical Universe Redshift Consider A Critical Universe Nm 1 Without Dark Energy 121 0 And A Local Hubble Constant 2 (30.66 KiB) Viewed 46 times

Critical universe redshift Consider a critical universe Nm = 1 without dark energy (121 = 0) and a local Hubble constant equal to the currently inferred best-value H, ~ 70 (km/s)/Mpc. a. Derive a formula for redshift z versus distance d (in Mpe). b. Show that, for small distances d < c/H, this recovers the simple linear Hubble law cz = Hd.

c. Compute the time since the Big Bang (in Gyr). d. Compare this time to the age of a globular cluster with a main-sequence turnoff at luminosity Lto = 0.75L.. e. What does this say about the viability of this as a model for our universe? What about closed-universe models with 2m > 1? (Assume the above Hubble- constant measurement is accurate, and that there is no dark energy.)