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It's Official: LIGO Scientists Make First-Ever Observation of Gravity Waves (economist.com)
A few days ago, we posted reports that a major finding -- the discovery of the long-predicted gravity waves -- was expected to be formally announced today, and reader universe520 is the first to note this coverage in the Economist : It is 1.3 billion years after two black holes merged and sent out gravitational waves. On Earth in September 2015, the faintest slice of those waves was caught. That slice, called GW150914 and announced to the world on February 11th, is the first gravitational wave to be detected directly by human scientists. It is a triumph that has been a century in the making, opening a new window onto the universe and giving researchers a means to peer at hitherto inaccessible happenings, perhaps as far back in time as the Big Bang. Reader
DudeTheMath adds: NPR has a nice write-up of the newly-published results: "[R]esearchers say they have detected rumblings from that cataclysmic collision as ripples in the very fabric of space-time itself. The discovery comes a century after Albert Einstein first predicted such ripples should exist. ... The signal in the detector matches well with what's predicted by Einstein's original theory, according to [Saul] Teukolsky [of Cornell], who was briefed on the results."
Update: 02/11 18:08 GMT by T : Worth reading: this letter, inspirational and informative, from MIT president L. Rafael Reif, about the discovery. (Hat tip to Brian Kulak.)
Essentially a flexing of space, but it isn't easy to visualize. Imagine a circle as a gravity wave goes through it then the horizontal direction will get flattened and the vertical (direction of the wave) will get stretched out, and then the reverse. The actual equations for what it does to an object though are non-trivial.
Absolutely. My point was not so much about refuting relativity completely, but observing (at scales far beyond our normal ability to detect) data that suggests that relativity as we know it is an incomplete theory. Which has already happened, mind you, given that relativity did not at the time fully describe quantum physics and other phenomena.
But discovering that gravity waves didn't follow the pattern might have made LIGO a modern Michelson-Morley experiment, leading to completely new physics, just as relativity was a better description of gravitation and spacetime than Newtonian physics.
All my liberal friends think I'm a conservative, all my conservative friends think I'm a liberal.
Actually, no, this is a very important result. We've been looking for gravity waves for years, and until now had been unable to detect them despite looking at sources that we should have been able to detect. This detection essentially closes an "uncertainty gap" in the theory - think of it like replacing "Here there be Dragons" on an old map with, "Nothing but open ocean here". It doesn't really change much, unless you happen to want to travel across the previously unknown area.
In addition, the article doesn't mention it, but by comparing the measured spatial distortions with he predicted values we open the door on the study of why the waves aren't as strong as predicted. Is there a flaw in the machine, or some hither-to unpredicted attenuation factor? The latter could potentially be every bit as earth-shattering as when the study of black-boy radiation revealed Quantum Mechanics.
It is in looking for confirmation of the predictions in current theory that both confirm that theory, and occasionally expose its flaws, which lays the groundwork for new theories. It may not be as exciting or glamorous as discovering something unexpected and new, but it's the same exact search that does both, and it's largely the luck of the draw as to whether the previously unexplored nook you chose to investigate reveals anything new. Its primarily through the exhaustive search of such nooks that we discover the unexpected phenomena that allows further theoretical growth. And in that pursuit "nothing unexpected here" is vitally important, as it allows future researchers to concentrate their attention elsewhere. Not to mention, it develops the early stages of the technologies that eventually allow us to harness the phenomena for productive uses.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
It still follows basic thermodynamics once you break it down.
No, it does not.
Neither quantum mechanics nor the relativity theory have anything to do with thermo dynamics, basic or not.
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
What's sort of amusing here is that the Michelson-Morley experiment, which is EXACTLY what this experiment is, failed to detect Ether. Yet this experiment is actually detecting ether! it's not the ether distortion MM were looking for which is differences in some vaccum substance that supports electromagnetic wave propagation. Instead it is detecting gravity wiggles in in real matter. Yet those gravity wiggles traveled through vacuum too. And according to general relativity my understanding is that should have distorted the vaccuum too. Thus if MM had had a sufficiently sensitive interferometer they would have detected these and attributed them to Ether fluctuations!
Some drink at the fountain of knowledge. Others just gargle.
We detected the electromagnetic ether a long time ago. Today we call it "the photon field." If we had a quantum field theory of gravity we'd call the gravity ether "the graviton field" but instead we settle for calling it spacetime.