Einstein and the New Universe
What is it?
Albert Einstein (1879-1955)
Education and Early Life
Born in Germany to a family that made electrical parts; later received Swiss citizenship (1901)
Famously a slow developer and modest student
Initially failed his college entrance exams, eventually getting a degree from the Federal Polytechnic Institute in Zurich (1900)
This picture is flawed, as we know that Einstein began speculating about math and nature as early as five
Not so hot college graduate
Unable to obtain a teaching job (see his father's letter to a potential employer)
Becomes a patent clerk, third class, in 1902
Again, this picture is flawed
Real problem getting a job was not his grades, but a former professor who wrote nasty "recommendation" letters
Was thinking a great deal about physics, and managed to get some minor papers published
Able to think beyond the Newtonian paradigm in part because he was self-taught to a great degree and had little contact with the scientific community
1905: The four papers of the miracle year
First paper laid the groundwork for quantum mechanics
Second paper substantially altered statistical mechanics and atomic theory
The third and fourth papers outlined special relativity
Background to Relativity - Newton's World Falls Apart
Newton had assumed space and time were fixed
In order to explain how light and the force of gravity flowed through space, he postulated the existence of an "aether"
The aether gave a fixed reference to measure all movement against, and it was the substance through which light and gravity flowed
Later, electricity and magnetism were seen as flowing thought the aether
But where is it? - The aether was invisible, without form, shape, color, or substance
As it turns out, the "aether" was a convenient mathematical fiction that made Newton's equations work.....
James Clerk Maxwell (1831-1879) and Michael Faraday (1791-1867)
Faraday showed that electricity and magnetism were the same, and they behaved as fields of force, not fluids
Maxwell's papers in 1855 and 1856 explained the mathematics behind these fields - no "aether" needed
Maxwell's equations were paradoxical in light of Newton's, but the revolutionary implication were not worked out until Einstein
There were practical implications
Because of the incompatibility, it was impossible to accurately predict how much power an electric dynamo would produce
Einstein's family tried to make money selling part for dynamos, so he was aware of the problem from an early age
The Michelson-Morley experiments
Set out in the 180s to study "aether drift"
If the aether was real, it should affect the observed speed of light coming from stars, because of the Earth's motion
Light coming to us from a star Earth was moving towards would appear to speed up, and slow down as we move away
By the 1880s, measurement technology was enough to catch what would be very small changes in the speed of light
But Albert Michelson and Edward Morley failed to find any drift - regardless of an object's motion, the speed of light coming from anywhere was the same
Huh? This made no sense at all....
Hedrick Antoon Lorenzt
Some people suggested that the light only seemed to be going the same speed because the Earth shortened in the direction just enough to make it look that way
This seemed preposterous to many, but Lorenzt worked out the math
Lorenzt contraction would become the basis for much of Einstein's work
1905 - Special Relativity
The Universe is a Strange Place
Einstein takes Lorenzt and M-M at face value, accepting that the speed of light is the same for all observers
Regardless of what speed you are going, light coming from any direction appears to be going the same speed
That means we do contract in the direction we are moving, as in Lorentz
As well, the faster we go, the more mass we have - and time slows down for us as well
Oh, and since we get steadily more massive and move through time slower as we speed up...
we get to be infinitely massive and stop moving through time when we get to the speed of light
in other words, we can't go the speed of light, and we sure as heck can't go faster
Space, time, and mass are not constant - only the speed of light is
Oh, and it can go boom in a big way, too
Things get more massive as they go faster
In other words, they get more massive when they absorb matter
They thus should give off energy as they get less massive
Which would indicate some kind of relationship between energy and mass, like maybe some equation could show that relationship.....
1915 - General Relativity
What the heck is gravity?
Einstein was inspired by the realization that a person who is falling does not feel his own weight to study gravity
He also thought about the fact that gravity and acceleration feel like the same thing - the G forces a jet pilot feels feel like a weight pressing down
What if then gravity and acceleration where the same thing?
Enter Hermann Minkowski
Minkowsi was a former professor of Einstein's
He cleaned up Einstein's math, and along the way, showed that special relativity meant that space and time were not independent of each other - they were one, the "space-time continuum"
But if gravity is acceleration, and acceleration is a ratio of movement through space and time, what does it mean that space and time are one?
The Big Curve
What Einstein worked out over nearly a decade was that space itself is curved
Gravity then is simply curved space, with matter bending space itself (and time! - don't get near a black hole!)
And if that doesn't confuse you, nothing will