# Relativity

This video is about Albert Einstein’s amazing theory of Special Relativity.

For a short outline of the contents of this video, see the summary.

For a complete written record of the words in this video, see the transcript.

A summary of Einstein’s theory of Special Relativity can be found here:

http://www.einstein-online.info/elementary/specialRT

If you’re curious to get a glimpse of some of the mathematics behind Special Relativity, take a look at this webpage:

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/ltrans.html

These videos provide a different perspective on Special Relativity and $$E = mc^2$$ :

https://youtu.be/ajhFNcUTJI0

https://youtu.be/hW7DW9NIO9M

## Research Challenges

• When Albert Einstein invented his theory of Special Relativity, he built off of the works of many other physicists. Who inspired Einstein to develop this theory and what unique insight did Einstein have to formulate his theory?

• Special Relativity has some unusual implications regarding the nature of time. One of these is called the twins paradox. Does the twins paradox indicate that time travel is possible?

• When Albert Einstein formulated his theory, he relied on numerous thought experiments (what he called gedankenexperiments), imagining what it would be like to travel close to the speed of light. Did Einstein’s imaginary experiments prove his theory to be correct? What kind of physical tests have physicists performed to verify Special Relativity?

• Einstein’s theory of Special Relativity was followed by his theory of General Relativity. What are the differences between the two theories and how are they similar? How does General Relativity relate to black holes and cosmology?