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Gravitational Waves May Have Been Detected In 1987
KentuckyFC writes "In 1987, a physicist called Joe Weber claimed to have detected gravitational waves at the same time that other scientists spotted a supernova called SN1987A. His claims were largely ignored because of calculations showing that gravitational waves could not be strong enough to be picked up by Weber's equipment, a set of giant aluminium cylinders designed to vibrate as the waves passed by. But these calculations were based on first order effects in the way spacetime can be distorted. Now a new analysis shows that second order effects can enhance gravitational waves by four orders of magnitude, but only when certain asymmetries are present. It turns out that SN1987A possesses just the right kind of asymmetries to make this enhancement possible because the supernova wasn't entirely spherical. Which means that Weber, who died in 2000, may have been the first to see gravitational waves after all."
Can this be awarded posthumously ?
One thing I've never liked about the current popular gravity model, you know, the one they discuss on discovery channel, usually for a cosmology special, where they discuss how gravity distorts space-time, and then you get to see a CGI animation of a large ball on a rubber like grid -drawn as a 2 dimensional analogy- and the ball is pushing down on the grid, making an indentation in it, and another, smaller, ball starts circling the bigger ball, eventually falling in towards the larger ball..
Isn't that like using gravity to explain the effect of gravity?
Look back up at my post, now look back down, you're on the Internet. Now look back up. I'm a signature.
As already mentioned in a previous comment, the article is somewhat speculative and it is a little bit late to verify the experiment. The standard accepted practice for claiming the detection of a GW is to observe the event with at least 2 detectors which are separated far enough to not measure the same external disturbances (but preferably 3 or more spread around the world so that you can do proper triangulation of the source). One single glitch might be a cosmic ray, lightning, dust falling before your detector, an earthquake, an instrumental error, anything. We see more of those than we like. One glitch measured at different observatories within the time it takes to travel at lightspeed (a few ms) at different observatories around the world might give you a nobel prize.
One book that is high on my 'to read' list is Gravity's shadow, which supposedly describes not only Weber's experiments, but also its reception by the scientific community and the eventual downfall of Weber's reputation.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
Er, no, you don't "truly" see anything. Your brain forms a representation of reality based on sensory input. In the visual side of that, the spatial representation is 3D.
Furthermore, you don't "see" in 2 dimensions, in your understanding of the word (which is kinda meaningless, cf visual illusions, hallucinations etc), because of the parallax effect afforded by having two eyes.
Also, the complete internal representation of a thrown ball is fundamentally 4 dimensional (3 spatial + 1 temporal). But it's hard to visualize curvature of 4 dimensional spacetime.
Azural - instrumentals
I don't like to speak ill of the dead, so I will leave it at that.
I saw the setup in the winter of late 1986. It was deep (many levels) under the physics department's machine shop, deep underground, at the University of Maryland & you had to go down several ladders to get there. It was hanging from the ceiling, big giant (I thought hollow, but apparently solid) cylinders of what looked like aluminum, hanging from thin wires. Does anyone know if it is still there?
In 1980 I met with Joe Weber at the Jet Propulsion Lab.
He had been reducing the noise in his experiment over the decades was still confident that the disturbances he was recording were gravitational waves.
Rather that being bitter about the 20 years of skepticism concerning his experiment, he was upbeat and optimistic. He understood that the theorists claimed that he could not possibly being seeing gravitational waves, but, as he told me, "You are not going to see them if you don't look!"
The reason he was at JPL was that John Anderson, Frank Estabrook, and Hugo Walquist conducted searches for gravitational waves using high precision spacecraft tracking during the 1970s and continue to search to this day.