3D Space: Illusion or Reality?

This video excerpt from NOVA’s "The Fabric of the Cosmos: What Is Space?" reveals new data about black holes that has led to a new idea about the universe: Instead of everything being a three-dimensional object, it’s possible that everything is actually just a hologram.

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Beyond Einstein

NASA scientists describe some of the ways current science is addressing several of Einstein's fundamental questions and theories in this video adapted from NASA.

Einstein: A Timeline of His Life

This illustrated timeline from the NOVA Web site follows Albert Einstein's life, including 1905, his "Miracle Year," during which he developed his Special Theory of Relativity and the equation, E=mc².

Einstein: How Smart Was He?

This essay from the NOVA Web site explores the impact Einstein made on physics and most everything we know about the cosmos.

Einstein's Innovative Thinking

Students are introduced to two of Einstein's most famous theories -- special relativity and general relativity -- and what he was thinking when he developed them.

Einstein's Special Theory of Relativity

What happens when you approach the speed of light? This video segment adapted from NOVA follows one of Albert Einstein's thought experiments and his quest to find the answer.

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Einstein's Thoughts on the Ether

Do light waves travel through the ether like waves on a lake travel through water? In this video segment adapted from NOVA, a young Albert Einstein grapples with this question while examining the speed of light.

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Frames of Reference

Explore how different frames of reference affect your perception of motion in this interactive activity from the American Museum of Natural History.

The Light Stuff

This interactive activity from the NOVA Web site asks which items in your home can slow down the speed of light.

Motion and Relativity

This video from the American Museum of Natural History illustrates how motion is described relative to a frame of reference, and how Einstein's special theory of relativity is needed to describe the motion of objects traveling near the speed of light.

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Sagan on Time Travel

Astronomer Carl Sagan discusses the possibility of time travel in this audio-enhanced interview from the NOVAWeb site.

Speed of Light: How Fast Is That?

How fast is 300,000 kilometers per second? This text from the NOVA Web site offers a few real-world comparisons for the speed of light.

Speed of Light: Time Traveler

This interactive game from the NOVA Web site explores what happens to time as a traveler approaches the speed of light.

Think Like Einstein

This interactive activity from the NOVA Web site challenges you to think like Einstein and understand how time travel might be possible.

Time and Relativity

This video from the American Museum of Natural History illustrates Einstein's special theory of relativity and the relationship between time and the motion of objects, including the concept of time dilation.

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Traveling Through Time

This video excerpt from NOVA’s "The Fabric of the Cosmos: The Illusion of Time" explains gravity’s pull on time, and how time travel may be possible in the future. However, this kind of time travel might not be exactly like Hollywood’s depiction.

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