The equation for cosmological redshift where z << 1 is is commonly given as z = λobs / λemit -1(adsbygoogle = window.adsbygoogle || []).push({});

What is the equation for high-z, accounting for how light surpasses the spatial expansion it leaves behind, but abstracting from gravitational influences? I'm particularly interested in how CMB can be calculated to have a z of only ~1100 if it dates from 380,000 years from the start of cosmological expansion, which would indicate a z of 13,750,000,000 / 380,000 -1, or more than 36,000.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# What is the equation for high (cosmological) redshift?

**Physics Forums | Science Articles, Homework Help, Discussion**