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Spacetime and Einstein. 1905: Clerk in Patent Office. Schoolboy. 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.
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Spacetime and Einstein 1905: Clerk in Patent Office Schoolboy 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.
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! Shorter Slower Heavier Space and time get mixed up . . . Spacetime! Question: If we disagree about measurements, what can we agree on? Answer: The speed of light is the same for everyone! Some “unintended” consequences:
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! • The protons: • Seem 1000 times heavier. • Seem 1000 times thinner. • Have clocks that run 1000 • times slower. 4 MILES
Space & time are bent, or curved, by matter. www.unmuseum.org 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! . . . www.unmuseum.org
Space is bent by matter. Multiple images (like ripples on a pond) Same Galaxy See it twice!
Spectral lines - Cosmic Barcodes neon hydrogen
Red shift Blue shift (Object moving away) (Object moving toward) eeeeyaooww!! www.astro.ucla.edu/%7Ewright/doppler.htm
A tiny spot from the Hubble Space Telescope Every blob is a galaxy with ~100,000,000,000 stars. All are rushing away from us, RED SHIFT . . . expanding Universe! Dr. Hubble (Wheaton) discovered that. BIG BANG 13.5 billion years ago But not BIG, TINY!
Extrasolar Planets SPEED TO/FROM US TIME exoplanets.org/neptune_web/neptune_graphics.html Artist’s impression 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
Black Holes From Astronomy Picture of the Day www.phy.mtu.edu/apod/ap971107.html The Black Hole is invisible, but you can see stuff around it.