It appears gravitational waves have been detected. From what I've heard, they have a 5 sigma signal which they should announce in about twenty minutes. (9:30 AM CST). Link to the NSF live stream of the gravitational wave announcement:

Yes.

The link I posted above actually takes you here:

Engrish?

This isn't gonna mess up my DVR settings to record Duck Dynasty and WWE Smackdown XVIXVII is it? I have directTv.

There are no weird bookshelves in your TV room where books mysteriously fall off, are there?

Apparently this is a big deal.

I'm still waiting on cold fusion.

Pretty cool. Now astronomers don't have to deal exclusively in light.

Now we know that gravity is not constant. If gravity is correlated to mass, does that mean we've disproven conservation of mass? Or have we disproven that gravitational force is a function of mass?

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Now we know that gravity is not constant. If gravity is correlated to mass, does that mean we've disproven conservation of mass? Or have we disproven that gravitational force is a function of mass?

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I'm not too sure what you mean by this.

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Now we know that gravity is not constant. If gravity is correlated to mass, does that mean we've disproven conservation of mass? Or have we disproven that gravitational force is a function of mass?

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I'm not too sure what you mean by this.

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Force of Gravity (Fg) is defined as the force between two objects with masses M1 and M2, radius r, and gravitational constant G. Fg = (G*M1*M2) / r^2.

The recent discovery shows that given two objects with masses M1 and M2 and radius r, Fg isn't always constant. We now know that force of gravity can radiate in waves, and so it is not constant between two objects at a constant radius. So the gravity formula doesn't work anymore.

So either mass can be created or destroyed (without being converted to energy), or the gravitational constant is no longer a constant and is now a variable that changes based on how the gravity waves are acting on the objects. (That's the easiest solution, but it might not be the right one) Or I guess our concept of distance no longer applies and a meter can no longer be defined as a constant quantity of length.

E=MC^ is gone

So if the equation doesn't work, how did we go to the moon?

I'm a physics amateur (liberal arts major) but I do try to read and learn as much as I can. I'm not following as to why this overturns E=mc^2 or the conservation of mass. These gravitational waves are essentially ripples in spacetime itself, correct? If spacetime itself had a wave going through it, then it seems obvious that neither distance nor time would be a constant along the wave. What is so revolutionary about that? We already know time isn't a relative constant. Just as when you drop a rock in a pond, the energy goes out in a wave like fashion at a given speed. We also already knew that gravity can't travel faster then the speed of causality (c), so why wouldn't it travel in waves?

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Now we know that gravity is not constant. If gravity is correlated to mass, does that mean we've disproven conservation of mass? Or have we disproven that gravitational force is a function of mass?

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I'm not too sure what you mean by this.

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Force of Gravity (Fg) is defined as the force between two objects with masses M1 and M2, radius r, and gravitational constant G. Fg = (G*M1*M2) / r^2.

The recent discovery shows that given two objects with masses M1 and M2 and radius r, Fg isn't always constant. We now know that force of gravity can radiate in waves, and so it is not constant between two objects at a constant radius. So the gravity formula doesn't work anymore.

So either mass can be created or destroyed (without being converted to energy), or the gravitational constant is no longer a constant and is now a variable that changes based on how the gravity waves are acting on the objects. (That's the easiest solution, but it might not be the right one) Or I guess our concept of distance no longer applies and a meter can no longer be defined as a constant quantity of length.

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I am not a physicist, but my understanding is that Newton's equation of gravity is a simplification of the one Einstein "discovered" during his work with relativity. Newton's equation holds for small masses (relative to something like a black hole) and slow velocities (relative to the speed of light).

So, for the Earth orbiting around the Sun, you can use Newton's equation to make accurate predictions about forces and motion. But for 2 black holes orbiting each other and eventually colliding at half the speed of light, you need to use Einstein's equations.

Here's an article that probably explains it better than I could: https://plus.maths.org/content/what-general-relativity

Wouldnt the gravity just go back to being constant when the wave passes. Kinda like a wave on a pond no.

For us slows...

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Wouldnt the gravity just go back to being constant when the wave passes. Kinda like a wave on a pond no.

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Yes

I think this changes very little. The oscillations of the black hole are the big discovery IMO

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Wouldnt the gravity just go back to being constant when the wave passes. Kinda like a wave on a pond no.

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Yes

I think this changes very little. The oscillations of the black hole are the big discovery IMO

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This is the now most definitive evidence for the existence of black holes.

AND

It also proves Einstein's theory about gravitational waves.

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Wouldnt the gravity just go back to being constant when the wave passes. Kinda like a wave on a pond no.

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Yes. The observers were set up to measure a tiny, tiny momentary change in length along a 2 mile long tunnel caused by the gravity waves. (On the order of the size of an atomic nucleus.)

The point of the experiment was to prove/disprove Einstein's theory about the fundamental nature of gravity.

Theoretically, shouldn't anything with mass/momentum produce gravity waves? Obviously we don't have the tools to detect anything less than 2 of the most massive things in the universe colliding with each other, but the idea of a "constant gravity" really just means that any fluctuations in gravity are small enough as to be imperceptible by us, right?

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Theoretically, shouldn't anything with mass/momentum produce gravity waves? Obviously we don't have the tools to detect anything less than 2 of the most massive things in the universe colliding with each other, but the idea of a "constant gravity" really just means that any fluctuations in gravity are small enough as to be imperceptible by us, right?

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According to my understanding, yes.

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Theoretically, shouldn't anything with mass/momentum produce gravity waves? Obviously we don't have the tools to detect anything less than 2 of the most massive things in the universe colliding with each other, but the idea of a "constant gravity" really just means that any fluctuations in gravity are small enough as to be imperceptible by us, right?

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Yes. Asolutely. The waves occur even when you walk past someone or something else. They're just extremely miniscule.

It seems that it would be correct to say this is less of a 'wow, look at this new thing we found' kind of discovery and more of an 'oh cool, we've been on the right track all along' kind of thing. Both kinds of results are obviously useful and important.

Also, to me this still seems like a logical and expected result (which I guess it was). The other field-based forces we know about (e.g. electromagnetism) travel in waves, so...why wouldn't gravity be the same? I feel like we would have needed a really good reason for there NOT to be gravitational waves.

The whole choice of the word "waves" is misleading to me. Should be gravitational ripple