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How Einstein Lost His Bearings, and With Them, General Relativity (quantamagazine.org)
Kevin Hartnett, writing for Quanta magazine: Albert Einstein released his general theory of relativity at the end of 1915. He should have finished it two years earlier. When scholars look at his notebooks from the period, they see the completed equations, minus just a detail or two. "That really should have been the final theory," said John Norton, an Einstein expert and a historian of science at the University of Pittsburgh. But Einstein made a critical last-second error that set him on an odyssey of doubt and discovery -- one that nearly cost him his greatest scientific achievement. The consequences of his decision continue to reverberate in math and physics today.
Here's the error. General relativity was meant to supplant Newtonian gravity. This meant it had to explain all the same physical phenomena Newton's equations could, plus other phenomena that Newton's equations couldn't. Yet in mid-1913, Einstein convinced himself, incorrectly, that his new theory couldn't account for scenarios where the force of gravity was weak -- scenarios that Newtonian gravity handled well. "In retrospect, this is just a bizarre mistake," said Norton. To correct this perceived flaw, Einstein thought he had to abandon what had been one of the central features of his emerging theory. Einstein's field equations -- the equations of general relativity -- describe how the shape of space-time evolves in response to the presence of matter and energy. To describe that evolution, you need to impose on space-time a coordinate system -- like lines of latitude and longitude -- that tells you which points are where. Another interesting read on Quanta: Why Stephen Hawking's Black Hole Puzzle Keeps Puzzling.
Here's the error. General relativity was meant to supplant Newtonian gravity. This meant it had to explain all the same physical phenomena Newton's equations could, plus other phenomena that Newton's equations couldn't. Yet in mid-1913, Einstein convinced himself, incorrectly, that his new theory couldn't account for scenarios where the force of gravity was weak -- scenarios that Newtonian gravity handled well. "In retrospect, this is just a bizarre mistake," said Norton. To correct this perceived flaw, Einstein thought he had to abandon what had been one of the central features of his emerging theory. Einstein's field equations -- the equations of general relativity -- describe how the shape of space-time evolves in response to the presence of matter and energy. To describe that evolution, you need to impose on space-time a coordinate system -- like lines of latitude and longitude -- that tells you which points are where. Another interesting read on Quanta: Why Stephen Hawking's Black Hole Puzzle Keeps Puzzling.
In this era of computers and CPU's and constant distraction, he wouldn't have managed to get to even first realization. The Theory of Relativity was a triumph of abstract thought; this is something that doesn't really happen anymore.
the monumental effort to reconcile general relativity with quantum theory flounders in part because of the difficulty of developing a theory of quantum gravity that has the same general covariance Einstein achieved with his field equations. “In some sense you could argue the reason we don’t have an adequate quantum theory of gravity is we don’t know how to express the solutions to Einstein’s equations in a way that completely removes any kind of coordinate dependence,” said Weatherall.
It sounds like he recognized that there was something he couldn't explain, so he backed off a bit and looked for the explanation rather than charge forward and risk looking foolish.
... back.
WTF is this?
Hawking passes and we get Slashdot Esquire magazine?
It little behooves the best of us to comment on the rest of us.
Its hard to explain after Harrods was destroyed by the Vogons.
What actually happens when matter turns to energy and back?
It has never been observed to completion, only buildup of mass on high-speed particles and significant energy release on disassembly of atoms.
What's the difference between energy that is electromagnetic and energy that is motion?
How it interacts with other energies.
Why the difference?
They are essentially different, but also somewhat similar. That's why you are having trouble disconnecting the similarity in names from the difference in meaning.
Can you turn motion energy into photon energy?
There are many means of conversion.
Why not?
False.
Where does the value of C come from?
Observation and calculation.
Why is there a limit at all?
We suspect there is a limit because Maxwell's Equations have an asymptote at that value. We accept that there is a limit because high energy testing shows the predicted behavior.
Why is that limit exceeded by observation?
It hasn't been.
How come there are so many forces?
There are 4.
Why is gravity only an attraction force and others not?
Gravity and the strong nuclear force are attraction, the weak nuclear force is repulsion. Magnetism is directionally attraction.
What is time?
A direction.
Why does inertia and momentum require time?
By definition.
Why don't things happen instantaneuosly?
Things do, and trends don't.
What if they do? How would we perceive that?
You wouldn't. At best, your perception is functional on the order of 10^42 hypothetical distinct moments per AC observation.
What would motion look like in a world where everything happens instantaneously?
Have you been to a rave with a strobe light? Start from there.
Classical physics does not depend on a reference frame as long as the limitspeed is infinite and until 1880 or so that was the assumption. I mean it was known that the lightspeed was finite but there was no reason to believe it was the limitspeed. You can turn newtonian mechanics into a covariant system for general coordinate systems but why would you do that? If you want to describe a merry go round , don't get all that overhead and use a shortcut.
Then with special relativity you could again decide to do the same: support general coordinate systems, make it work for accelerated observers. You could still classify it as special relativity.
It was Einstein who decided we couldn't avoid to formulate things in a covariant manner, and the example was that inside an elevator it was strictly impossible to distinguish between floating in space or plummetting towards the earth in free fall and and likewise there was no distinction between standing on the surface of the earth and being pulled in space.
Therefore the math had to be the same too.
In this era of computers and CPU's and constant distraction, he wouldn't have managed to get to even first realization.
Such a bad example. Darwin delayed much longer than Einstein and it's doubtful whether anyone forced his hand at all.
He was a brilliant thinker who deserves full credit. Wallace didn't come close in any way.
...and yet every experiment to verify Relativity has shown Einstein to have been correct, whether it was 4 years after, or 100 years after publishing. Your stupid fucking electric universe bullshit requires Relativity to be wrong, yet everything points to Einstein being right.
Your pseudoscience cult is just fucking stupid.
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