a)Define the term “standard candle” as used in cosmology. b)The flux is defined asf(Dlum) = L/4πD^2lum where L is the absolute luminosity and Dlum is the distance to the radiation source (you may assume z ≪ 1). Assume that we have measured the flux to be f = 7.234 10^−23 Wm^−2 and the absolute luminosity is given by L = 3.828 x10^26W. Calculate the luminosity distance D lum to the object in Mpc.

a)Define the term “standard candle” as used in cosmology. b)The flux is defined asf(Dlum) = L/4πD^2lum where L is the absolute luminosity and Dlum is the distance to the radiation source (you may assume z ≪ 1). Assume that we have measured the flux to be f = 7.234 10^−23 Wm^−2 and the absolute luminosity is given by L = 3.828 x10^26W. Calculate the luminosity distance D lum to the object in Mpc.

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