Curved Spacetime and Black Holes

The Great Courses
Show More

Related videos

General Relativity
Episode 5 of Redefining Reality
Relativity was incomplete until Einstein formulated a general theory of relativity that incorporated gravity. See how this breakthrough demolished the age-old idea of gravity as a force, replacing it with the concept of warped spacetime, leading to strange predictions such as black holes.
Black Holes, Tides, and Curved Spacetime - Understanding Gravity Course
Gravity rules the universe. Without it, everything would dissolve into a gas of randomly interacting atoms. Yet gravity is one of the least understood forces in nature. Black Holes, Tides, and Curved Spacetime introduces you to key ideas in gravity research over the past 400 years. It's an awe-inspiring journey…
A Problem of Gravity
Historically, the path to general relativity followed Einstein's attempt to incorporate gravity into relativity theory, which led to his understanding of gravity not as a force, but as a local manifestation of geometry in curved spacetime.
Spacetime Tells Matter How to Move
See how gravity affects Minkowski's spacetime geometry, discovering that motion in a gravitational field follows the straightest path in curved spacetime. The curvature in spacetime is not caused by gravity; it is gravity. This startling idea is the essence of Einstein's general theory of relativity.
Gravity’s Horizon—Anatomy of a Black Hole
Plunge into the subject of black holes, which are massive objects that have collapsed completely under their own gravity. Learn how black holes distort spacetime and explore the supermassive black holes that lie at the hearts of galaxies. Then ask: Are there such things as micro-black holes?
Inside Einstein's Mind
Part of the Series: NOVA
On November 25th, 1915, Einstein published his greatest work: general relativity. The theory transformed our understanding of nature's laws and the entire history of the cosmos, reaching back to the origin of time itself. Now, in celebration of the 100th anniversary of Einstein's achievement, NOVA tells the inside story of…
Black Hole Entropy
Stephen Hawking showed that black holes emit radiation and therefore have entropy. Since the entropy in the universe today is overwhelmingly in the form of black holes and there were no black holes in the early universe, entropy must have been much lower in the deep past.
General Relativity
Special relativity is limited to reference frames in uniform motion. Following Einstein, make the leap to a more general theory that encompasses accelerated frames of reference and necessarily includes gravity. According to Einstein's general theory of relativity, gravity is not a force but the geometrical structure of spacetime.
Black Holes
General relativity is similar to Newtonian gravitation except in the case of very dense objects such as collapsed stars. Learn why they are called black holes.
Curved Spacetime
What causes spacetime to curve? Einstein's theory of relativity offers an answer, but for decades after he published it, there were only a few, very subtle tests of its validity. How has modern astrophysics changed all that?
Toward a Theory of Everything
Why can't we answer questions about what happened before the Big Bang, or what goes on at the center of a black hole? Can we manage the formidable task of combining quantum physics with general relativity? Physics may well be the most important subject in the universe, a theoretical realm…
Time and Relativity
According to Einstein's special theory of relativity, there is no such thing as a moment in time spread throughout the universe. Instead, time is one of four dimensions in spacetime. Learn how this "relative" view of time is usefully diagramed with light cones, representing the past and future.