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Examining Gravity Waves
Joseph "JoeDaMac" Haake writes "Sometime within the next two years, researchers will detect the first signals of gravity waves -- those weak blips from the far edges of the universe passing through our bodies every second. Predicted by Einstein's theory of general relativity, gravity waves are expected to reveal, ultimately, previously unattainable mysteries of the universe."
The LISA experiment, which gets mentioned in passing, is really quite audacious - three spaceships orbiting the sun in a clever rotating triangle pattern, 5 million miles apart from each other, and detecting changes in distance between each other to an accuracy of 20 picometers!
In essence, it's just a really, really big version of the Michelson interferometer we all played with in 1st year physics - I remember the thrill back then of realising what tiny changes in distance you could discern with just a couple of mirrors, a lamp and something to measure the recieved intensity.
It's exciting to witness the nascence of an entirely new form of astronomy.
Then we'd have to remove der liebe Herr Einstein from the pedestal of science, and put someone else there, someone who "saw clearly where everyone else saw nothing".
We didn't do that to Issac Newton did we?
I am very firmly convinced that the universe is far stranger than even the most brilliant minds alive today or yesterday ever give it credit for. I'm also very firmly convinced that no matter what mathmatical model we try to cram the universe into, we'll always find exceptions and things we don't understand. We'll find evidence to back up existing theories and postulates, yes, but we will also find evidence that takes current theories in a back alley, beats them across the head with a lead pipe, and then steals their credit cards.
Look at the research being done on gravity suppression or-- dare I say it-- anti-gravity. This research is considered quackerie and bad science by legitimate scientists who come across it. The fact remains, however, that this guy's research has such a huge potential to undermine existing theory and completely rewrite the books concerning propulsion that Boeing has made a major investment in his work.
One day, maybe one day soon, some scientist or group of scientists will make a major refinement on Einsteinian 'General Relativity' just as Einstein made a major refinement on Newtonian 'Classical Physics'. That doesn't mean that the work Newton did or the work Einstein did weren't major acheivments in and of themselves. It doesn't mean that they don't predict a great deal of what's going on, both out there in the cold reaches and here on Earth.
If you beleive that Einstein is 100% correct about everything he theorized then you're going to be in the same boat as people who beleived Newton was 100% correct. We don't know everything and we never will. Get over it already.
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Perhaps the most exciting thing about them is that we may well not know what it is we're going to observe. We think black holes, for sure. But who knows what else we might find?"
Jabba-The-Hut doing the Wild Thing.
"When we get a signal, we want to know what is generating that signal," Suen explained. "To determine that, we do a numerical simulation of a system, perhaps a neutron star collapsing, in a certain configuration, get the waveform and compare it to what we observe. If it's not a match, we change the configuration a little bit, do the comparison again and repeat the process until we can identify which configuration is responsible for the signal that we observe."
Sounds to me like they may be changing their model to fit the data in such a way that they won't know for sure it is a match. For example, a signal roughly fits the model of a black-hole forming, but not quite. They then keep tinkering with the black-hole formation model until it matches the signal. But in reality the signal could actually be something not related to black holes. They are putting the cart before the horse it seems.
It seems they would have to match a specific electromagnetic observation(s) to the gravity wave event to verify. Otherwise it is just a guess.
I could see some justifiable confidence if the signals were complex, and were only slightly off the models. In other words, near dead-ringer matches of something that would be too much of a coincidence to be something completely different generating the same (expected) complex signal. But I doubt we are at this stage in both the models and accuracy of the signal detection.
Table-ized A.I.
I wonder if they will be at all able to measure the speed of a graviton with this current setup. It seems as though they are having enough trouble just detecting them in the first place though. I think this is a first step towards a new branch of physics that uses gravitons in experiments. For instance, some spin-2 thermodynamics could be experimentally demonstrated if gravitrons could be isolated and easily detected. This is probably not going to happen any time soon, but LIGO is a big first step towards that goal.