Redshifts and important early events

In summary, the conversation discusses researching early universe historic eras and the redshifts at which certain events occurred. The recombination era had a redshift of z = 1100 and the reinonization era had a redshift of z = 15-20. The person is also looking for information on the "Dark Ages" and a good beginner level site on how redshift numbers are calculated.
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Hi,

I am researching several historic eras of the early universe and part of what I need to find is at what redshifts these events occurred. I have z = 1100 for the recombination era and z = 15-20 for the reinonization era. I haven't been able to turn up this info the "Dark Ages" yet. Any help is appreciated. And I'd be grateful if someone could point me to a good site (beginner level) on how these redshift numbers are calculated. Thank you.
 
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Thanks, Ambitwistor. I don't know what I'd do without you! I appreciate your help now as well as in previous posts.
 

1. What is redshift and how is it related to the expansion of the universe?

Redshift is a phenomenon where light from distant galaxies appears to have longer wavelengths, or "shifted" towards the red end of the spectrum. This is due to the expansion of the universe, which causes the space between galaxies to stretch and the light waves to stretch with it, causing a longer wavelength.

2. How is redshift used to measure the distance of galaxies?

Redshift can be used to measure the distance of galaxies through the Hubble's Law, which states that the further a galaxy is from us, the faster it appears to be moving away. By measuring the amount of redshift in the light from a galaxy, we can calculate how fast it is moving and therefore estimate its distance from us.

3. What are some important early events that can be observed through redshifts?

Some important early events that can be observed through redshifts include the formation of the first stars and galaxies, the reionization of the universe, and the cosmic microwave background radiation. These events provide valuable insights into the early stages of the universe's evolution.

4. Can redshift tell us about the age of the universe?

Yes, redshift can give us clues about the age of the universe. By measuring the redshift of the cosmic microwave background radiation, which is the leftover light from the Big Bang, we can estimate the age of the universe to be around 13.8 billion years.

5. How does the redshift of an object change over time?

The redshift of an object can change over time due to various factors, such as its distance from us, the expansion rate of the universe, and its own motion. As the universe expands, the redshift of an object will increase, while its motion towards or away from us can cause the redshift to decrease or increase, respectively.

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