Alexander Friedmann

High school (ages 12+)
Space & Astronomy

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Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/alexander-friedmann

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. When was Alexander Friedmann born?June 16, 1888
2. Where was Alexander Friedmann born?Saint Petersburg, Russia
3. What is the related topics?Cosmology, General Relativity, Big Bang Theory, Observational Cosmology, Lambda-CDM model
4. Who was Alexander Friedmann?He was a Russian mathematician and physicist born in 1888 who studied the universe using Einstein’s ideas. He showed that the universe could be moving, not just standing still.
5. What did Friedmann discover about the universe?He proved mathematically that the universe can grow bigger or shrink, meaning it is not fixed. His work said the universe has a beginning and keeps changing.

Homogeneous and Isotropic Universe: A universe that appears the same everywhere and in every direction on large scales.
General Relativity: Albert Einstein's theory of gravitation, which describes gravity as a geometric property of spacetime.
Cosmological Constant: A term introduced by Einstein into his field equations to allow for a static universe, later reinterpreted as a form of dark energy.
Redshift: The stretching of light waves from objects moving away from an observer, indicating cosmic expansion.