Support NeoGAF

[David Incorporated Esq.]

They travel at the speed of light. A Redditor stated that just like how light takes 8 minutes to reach the Earth from the sun, so does gravity. If the sun suddenly disappeared, Earth's orbit would stay the same for 8 minutes as the gravitational effect "travelled" to Earth.

I never quite understood this, thanks for the clear explanation. I suppose this would also mean that as you move faster and faster towards the speed of light the gravitational effects of your movement would build up in a wafefront ahead of you similar to a sonic shockwave at the speed of sound (just with additional limits that you can't get there).

 

[FyreWulff]

I never quite understood this, thanks for the clear explanation. I suppose this would also mean that as you move faster and faster towards the speed of light the gravitational effects of your movement would build up in a wafefront ahead of you similar to a sonic shockwave at the speed of sound (just with additional limits that you can't get there).

if you accelerated anything non-light to the speed of light, it would have infinite mass and energy, and instantly turn into a blackhole and consume the entire universe.

 

[theLusitanian]

I've been wondering, given how this confirms (correct me if I'm wrong on this whole idea) that gravity is the warping of space-time itself, that there are fundamental forces acting on the Universe that we might never be able to fully comprehend given that it affects our reality itself. For instance we don't know what dark matter is, but it seems to manifest via gravitation effects, so we would need to ..... leave?.... space time itself to see what dark matter actually is. This confirmation really boggles my mind more than anything.. especially the idea that the gravity waves pass through matter unimpeded.

 

[Raistlin]

This was the final major prediction for general relatively yet to be empirically tested, yes?

IIRC there's been a checkmark placed in front of all the others.

 

[FlyinJ]

I think the reason we haven't heard any aliens is because they are all communicating through gravity.

 

[Serpens007]

Sciencerrific!

 

[Dreams-Visions]

I think the reason we haven't heard any aliens is because they are all communicating through gravity.

those aliens must have a helluva lot of spare energy, given how much is required to make a ripple in gravity meaningful. Seems a rather inefficient way to ask your alien wife to pick up some alien milk at the alien grocery store, no?

 

[joshbob1985]

Up to now our only way of gathering information about the universe outside our solar system was to observe light waves (visible light + the rest of the EM spectrum; radio/micro waves etc).

There are limits on what this has allowed us to observe because:

-Most of the stuff in the universe does not emit or interact with light. So called 'Dark Matter' (it does cause gravitational lensing which is how we know it's there).

-The stuff that does emit or reflect light often has other stuff in the way, obscuring or distorting our view of it.

-For the first 380,000 years of the universes existence it was opaque, so we cant see anything from before that time using light.

-Black holes don't allow any light to escape so we can't see them.



But now we have a new source of information about the universe! Gravitational Waves!

GWs solve some of the problems above because they are not obscured by stuff being in the way and they can be caused by things that don't emit light.
We may be able to gather information from black holes and from the earliest time in the universe. This would be very handy because our current understanding of reality (which is based on General Relativity and Quantum Mechanics) falls apart in these situations.

 

[Mengy]

So this also confirms Half-Life 3, right???

Now come on, don't be silly. This is an incredible, world changing and fantastic discovery, but it's not a miracle like a confirmation of Half Life 3 would be.

 

[Raistlin]

Up to now our only way of gathering information about the universe outside our solar system was to observe light waves (visible light + the rest of the EM spectrum; radio/micro waves etc).

There are limits on what this has allowed us to observe because:

-Most of the stuff in the universe does not emit or interact with light. So called 'Dark Matter' (it does cause gravitational lensing which is how we know it's there).

-The stuff that does emit or reflect light often has other stuff in the way, obscuring or distorting our view of it.

-For the first 380,000 years of the universes existence it was opaque, so we cant see anything from before that time using light.

-Black holes don't allow any light to escape so we can't see them.



But now we have a new source of information about the universe! Gravitational Waves!

GWs solve some of the problems above because they are not obscured by stuff being in the way and they can be caused by things that don't emit light.
We may be able to gather information from black holes and from the earliest time in the universe. This would be very handy because our current understanding of reality (which is based on General Relativity and Quantum Mechanics) falls apart in these situations.

I guess the question becomes just how 'easy' is it to get this information.

Does this proof-of-concept mean techniques and technology for it will quickly evolve as has with radio telescopes, etc ... or is something that is inherently much more costly?

 

[E92 M3]

 

[joshbob1985]

I guess the question becomes just how 'easy' is it to get this information.

Does this proof-of-concept mean techniques and technology for it will quickly evolve as has with radio telescopes, etc ... or is something that is inherently much more costly?

Better versions are already in development. Europe is working towards a laser interferometer which will be in space and much more sensitive. Progress would be quicker if the Americans hadn't dropped support for the project, but China may join in.

 

[Sectorseven]

So what is the next step, build some kind of telescope, or do they already have one which is how they detected these waves in the first place?

 

[Alexlf]

So what is the next step, build some kind of telescope, or do they already have one which is how they detected these waves in the first place?

Right now we have extremely rudimentary technology in regards to detection, 2 sample points with low resolution. Kinda like 2 single grayscale pixels on your monitor to use an analogy.

To continue the analogy, now that we know gravity waves are a thing we can create new more precise ways to detect them and set up more detectors that will bring us from 2 pixels of grayscale to a future full color 1080p.

 

[Stinkles]

I never quite understood this, thanks for the clear explanation. I suppose this would also mean that as you move faster and faster towards the speed of light the gravitational effects of your movement would build up in a wafefront ahead of you similar to a sonic shockwave at the speed of sound (just with additional limits that you can't get there).

It's not really the speed of light or gravity but simply the speed limit of events in spacetime. Spacetime itself isn't actually limited in the same way. Think of it as a syrup expanding outwards. Stuff in the syrup can travel at lightspeed but the syrup itself can go faster. So all the stuff inside the syrup is still moving at lightspeed relative to other syrup inhabitants.

 

[J-Fr]

This is very exciting! It brings to my mind a lot of questions.

If dark matter objects react to gravity, could we detect them?

If two gigantic black holes produce a ridiculously small wave, a droplet of water would produce something smaller than the Planck length? (What about atoms? I'm not sure if they are affected by gravity?)
I guess water stops producing ripple at a certain threshold, if you drop a few molecules of water onto a few other molecules it will just move things around a little.
What about gravitational waves, the medium they go through is space itself, can they go infinitesimally small? Do they "loose strength" too?

If the two objects produce more and more waves as they orbit closer and closer, why didn't they detect more waves?

 

[alundra311]

I think they used GR to calculate what the gravitational wave produced by two colliding black holes would look like and it matched their measurements.

I see. It makes sense. I also wonder how people come up with such formulas and theories. Such people are years ahead of their time.

 

[titiklabingapat]

Aren't there plans to build LIGO like instruments in space now? Like using multiple satellites to ping the laser between each other. And instead of 4km, the distance between the these satellites will be hundreds of thousands of km IIRC, which means it will increase the sensitivity substantially.

 

[Dreams-Visions]

Aren't there plans to build LIGO like instruments in space now? Like using multiple satellites to ping the laser between each other. And instead of 4km, the distance between the these satellites will be hundreds of thousands of km IIRC, which means it will increase the sensitivity substantially.

well that would be pretty epic.

 

[Damerman]

I feel like this has time travel implications.

 

[DarkKyo]

I feel like this has time travel implications.

Detecting universe fabric quivers has nothing to do with implicating time travel, sorry. That's like saying reading a book can make the fantasy world within the book a reality. You're just observing the words, there's no way to make them come off the page.

 

[Damerman]

For those who want a better explanation:

https://www.youtube.com/watch?v=FXlg3cr-q44

Every single ounce of that video is mind blowing. I really hope the people who engineered LIGO won a Nobel prize. What the fuuuuuuuuuck.

 

[Damerman]

Detecting universe fabric quivers has nothing to do with implicating time travel, sorry. That's like saying reading a book can make the fantasy world within the book a reality. You're just observing the words, there's no way to make them come off the page.

Breh ur on a fucking video game forum. How could u say this?

Also I think ur analogy doesn't work. I meant time manipulation. The same way we are able to detect radio waves and manipulate them, there is no saying that we can't manipulate gravitational waves now that we have a primary detection of them

 

[fanboi]

So if we can detect these from a black hole, how does these waves escape the event horizon? Or is it before the event horizon these come from?

 

[Damerman]

So if we can detect these from a black hole, how does these waves escape the event horizon? Or is it before the event horizon these come from?

I'm pretty sure that only applies to mass and light, not gravity.

Edit: nvm, I don't know what I'm talking about.

 

[titiklabingapat]

well that would be pretty epic.

I was wrong. The distance between the satelittes will be millions of kilometers!

https://en.wikipedia.org/wiki/Evolved_Laser_Interferometer_Space_Antenna

2034 though, with the Japanese and Chinese ones launching a little earlier.

 

[FyreWulff]

So if we can detect these from a black hole, how does these waves escape the event horizon? Or is it before the event horizon these come from?

The absurd mass the black holes had was churning up space-time around them.

edit:

think of when someone is making a bed and they whip the bedsheet to create a wave. That's basically what the blackholes did to space-time. The blanket itself never moved and neither did your hands, but the distortion still rippled outwards from them.

 

[Morrigan Stark]

Is the LIGO system safe from say, tectonic plate movement affecting the distance between mirrors and detectors?

They have two locations working right now and both detected it independently. And yeah there was an article explaining why there are failsafes for that, I'm sure they thought of that, but I admit the thought had crossed my mind too.

Man I really regret not having pursued that astrophysics career when I was younger...

The 1000 scientists would cover it up to get payed and the other millions was already accepting of gravity waves existence due to theoretical work.

I mean, electricity is everyday witchcraft, but we all accept it as science because someone told us to.

............................

Sarcasm?

 

[Dreams-Visions]

I was wrong. The distance between the satelittes will be millions of kilometers!

https://en.wikipedia.org/wiki/Evolved_Laser_Interferometer_Space_Antenna

2034 though, with the Japanese and Chinese ones launching a little earlier.

well..that's a long time from now.