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Physicists Detect Gravitational Waves, Proving Einstein Right

nytimes.com

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Re: Physicists Detect Gravitational Waves, Proving Einstein Right

#41

Post by yk »

nickhalfasleep wrote: post #34
pinkrooftop wrote: post #18

Would it be possible to listen for information transmitted via gravitational waves? Would there be any benefit over radio?

This event was the equivalent of three of our suns turned into pure energy. Pretty expensive to send a message.

Burning a few suns per message would significantly reduce spam.

Re: Physicists Detect Gravitational Waves, Proving Einstein Right

#43

Post by Steuard »

4k wrote: post #29

I have a question: what does this mean for theoretical physics? (except for Einstein was right) Does it settle any major debates? Does it make any competing theory more or less likely? Sorry I am not vary knowledgeable on the topic.

It's by far the most explicit verification we've ever had that black holes exist in pretty nearly the exact form predicted by Einstein's equations of general relativity, which is pretty cool. It provides the tightest limits on any possible mass for the graviton (the presumed particle carrying the gravitational force, which is generally believed to be massless but you always have to wonder about more exotic possibilities). It gives a stunningly clear confirmation that modern numerical simulations of relativistic dynamics are an accurate reflection of nature. (And by the same token, it presumably puts limits on the strength of any potential deviation in the laws of physics from the equations used in designing those simulations.) And it probably does something to give preference to models of astrophysics in which binary systems with these characteristics are common.

Beyond that, I guess I'd say that this particular signal doesn't feel like that much of a surprise: we were already pretty confident that if a black hole binary were to merge, a signal more or less like this would be an expected result. The scientists were evidently surprised that their very first signal was so strong (this one was even borderline detectable by the previous version of LIGO), which may teach us something, but it's not revolutionary.

Re: Physicists Detect Gravitational Waves, Proving Einstein Right

#45

Post by elektropionir »

omgitstom wrote: post #27
pinkrooftop wrote: post #18

Would it be possible to listen for information transmitted via gravitational waves? Would there be any benefit over radio?

I think if you really wanted to think outside of box for this, quantum entangled particles is your best bet for instantaneous low energy communication

You can't transmit information through entangled pairs. What is instantaneous is the change of the state for the whole system (the pair) after you measure one of particles. However the result of that measurement (if it's non-trivial, i.e. if the measurement actually changes the state) is fundamentally random so the only thing you would be seeing is perfectly and instantaneously correlated noise on both ends.

Re: Physicists Detect Gravitational Waves, Proving Einstein Right

#46

Post by oldmanjay »

shmerl wrote: post #37
oldmanjay wrote: post #35

A detector of this sensitivity seems like a boon for spying. Rather difficult to relocate, fortunately, but it makes me wonder about the future of the technology. No one would have looked at the first computer and envisioned an iPhone.

> No one would have looked at the first computer and envisioned an iPhone. Not really. Portable computers were envisioned quite a long time ago.

Not before they were solid state. Computers had their own buildings and relied on glass tubes for operation. Screens weren't on the radar. Operators were highly educated. But technology did bring us to a point where the vision became more focused, and led to what we have today.

There are many possible paths to rebutting my statement, which to be clear is idle morning musing, but your objection doesn't hold water.

Re: Physicists Detect Gravitational Waves, Proving Einstein Right

#47

Post by scrumper »

From the abstract of the paper, energy equivalent to three solar masses were radiated away in gravitational waves. That's a simply incredible amount!

Possibly stupid question: Given how far away it was, and that the inverse square law applies, would the effect of these waves be visible on the human scale if we were closer? We can see the effects of the compression of spacetime with LIGO after all, so presumably we could?

Re: Physicists Detect Gravitational Waves, Proving Einstein Right

#48

Post by misnome »

losvedir wrote: post #4

> And then the ringing stopped as the two holes coalesced into a single black hole, a trapdoor in space with the equivalent mass of 62 suns. All in a fifth of a second, Earth time. Am I reading this correctly, that shortly after the detector came online we just happened to observe the exact moment a billion years ago that two black holes collided? Was that extremely coincidental? Or do these events happen all the tim…

In the press conference Kip Thorne mentioned that the estimates were for several events per year, before sensitivity upgrades.
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