relativity
Astronomy Cast Ep. 370: The Kaufmann–Bucherer–Neumann Experiments
One of the most amazing implications of Einstein's relativity is the fact that the inertial mass of an object depends…
How Can Space Travel Faster Than The Speed Of Light?
Cosmologists are intellectual time travelers. Looking back over billions of years, these scientists are able to trace the evolution of…
Don’t Look At Black Holes Too Closely, They Might Disappear
We've come a long way in 13.8 billion years; but despite our impressively extensive understanding of the Universe, there are still…
What is Gravitational Lensing?
Gravity's a funny thing. Not only does it tug away at you, me, planets, moons and stars, but it can…
How are Energy and Matter the Same?
As Einstein showed us, light and matter and just aspects of the same thing. Matter is just frozen light. And…
What Would It Be Like To Fall Into A Black Hole?
Let's say you happened to fall into the nearest black hole? What would you experience and see? And what would…
What Time is It in the Universe?
Check your watch, what time is it? But wait, you've actually been moving and accelerating, and according to Einstein, everything's…
Does Light Experience Time?
Have you ever noticed that time flies when you're having fun? Well, not for light. In fact, photons don't experience…
The Secret of the Stars
"Say, do you like mystery stories? Well we have one for you. The concept: relativity." Well look at that, it's…
Do We Really Need Dark Matter?
Hubble mosaic of massive galaxy cluster MACS J0717.5+3745, thought to be connected by a filament of dark matter. Credit: NASA, ESA,…