Spacetime and Einstein
1905: Clerk in Patent Office
Grand Old Man!
Einstein's Three Great Discoveries
He verified the existence of “atoms” by explaining the zig-zag motion of pollen
grains in water, noticed 80 years earlier.
He proved that light could be understood as little “bullets” of energy (or particles).
He developed the theory of relativity, in which “moving” observers disagree about simple measurements like time and distance.
Discovery #3 showed that space and time are mixed up . . . something that even today seems pretty weird.
Question: If we disagree about measurements, what can we agree on?
Answer: The speed of light is the same for everyone!
Some “unintended” consequences:
From your point of view moving things seem:
But the speeds have to be very big to make much difference.
You can go faster and faster but never ever reach the speed of light!
Space and time get mixed up . . . Spacetime!
Fermilab’s Accelerator pushes protons to:
0.9999995 x (speed of light)
(This is about 186,000 miles per second!)
Every second, they go around the 4-mile ring about 50,000 times!
Seem 1000 times heavier.
Seem 1000 times thinner.
Have clocks that run 1000
Space & time are bent, or curved, by matter.
This is gravity.
Planets, moons and baseballs go
“as straight as they can.”
May 29, 1919
The eclipse that changed the universe . . .
And proved Einstein right!
Space is bent by Sun’s gravity!
Space is bent by matter.
Multiple images (like ripples on a pond)
See it twice!
(Object moving away)
(Object moving toward)
A tiny spot from the Hubble Space Telescope
Every blob is a galaxy with ~100,000,000,000 stars.
13.5 billion years ago
But not BIG, TINY!
All are rushing away from us,
RED SHIFT . . . expanding Universe!
Dr. Hubble (Wheaton) discovered that.
Graphic of the Neptune-Mass companion to GJ 436
The Cosmological Constant
Einstein’s greatest blunder . . .
or perhaps his greatest legacy?
a case for the accelerating Universe
From Astronomy Picture of the Day
The Black Hole is invisible,
but you can see stuff around it.
Hubble Uncovers Dust Disk Around a Massive Black Hole