Gravity as a wave

[Alpo]

Breaking News!Neutron Star Merger affecting glass surfaces!

https://www.wimp.com/thats-one-scary-bridge/

 

[BugI02]

In another dimension I don't have to work and I can ponder the meaning of life. To me some of this stuff seems like made up malarkey shoehorned into an equation in order to make it work.

We are standing on the shoulders of giants, don't stand on an *******.

Just keep in mind that the practical application of certain math is lagging 30 to 50 years behind the development of the mathematical theory. The beard-pullers are making sure the scaffolding is always there when we need to build a new framework

 

[indiucky]

I'm always amazed by the ways we find that our universe has ordered itself...randomly... With no outside assistance... Or design intent whatsoever..,

 

[Alpo]

Just keep in mind that the practical application of certain math is lagging 30 to 50 years behind the development of the mathematical theory. The beard-pullers are making sure the scaffolding is always there when we need to build a new framework

Tensor equations: Gregorio Ricci-Curbastro, 12 January 1853 – 6 August 1925, was an Italian mathematician who formed a research group in which Tullio Levi-Civita worked, with whom he wrote the fundamental treatise on absolute differential calculus (also known as Ricci calculus) with coordinates or tensor calculus on Riemannian manifold, which then became the lingua franca of the subsequent theory of Einstein's general relativity.

Einstein knew nothing of tensor calculus when he began his work on the general theory of relativity. In 1912, he was mentored through tensors by Marcel Grossman.

 

[Tanfodude]

This guy is one of my favorite science reporters.

[video=youtube_share;EAyk2OsKvtU]http://youtu.be/EAyk2OsKvtU[/video]

[video=youtube;iphcyNWFD10]https://www.youtube.com/watch?v=iphcyNWFD10&t=212[/video]

 

[T.Lex]

http://www.bbc.com/news/uk-england-cambridgeshire-41721585

Figured this was a better place than the Science thread.

ETA:
For some reason the url didn't resolve to the page title. Basically, they're making Hawking's 1966 thesis on the expansion of the universe an open document. So many people were interested that the page for the repository crashed.

 

[T.Lex]

https://www.bbc.com/news/science-environment-46428010

So, they've confirmed more incidents that generated gravitational waves. Including the July 2017 merger of 2 black holes that are 5 billion light years away.

 

[bobzilla]

https://www.bbc.com/news/science-environment-46428010

So, they've confirmed more incidents that generated gravitational waves. Including the July 2017 merger of 2 black holes that are 5 billion light years away.

technically didn’t the merger happen5billion +/- years ago?

 

[Leadeye]

Easy to see gravity as waves if you see it as a phenomenon of something displaced by the presence of mass.

 

[T.Lex]

technically didn’t the merger happen5billion +/- years ago?

So... about that... I think the best answer is that we aren't sure. (Although, my post was REALLY not clear. The measurement appears to have been taken on July 29, 2017, of the event that occurred 5bn light years away.)

The "model" allows for faster-than-light "travel" of certain kinds of waves. They may not actually travel "faster" than light, but may disrupt time so that they seem to travel faster than light.

Having said that, that is still pretty theoretical. Actual testing appears to reveal that part of the difference is that light doesn't always travel at the speed of light. Light traveling in a vacuum hits the "speed limit." But, light across space doesn't always travel in a vacuum, so it can get slowed down.

But, the gravitational waves are generally accepted to travel at the max speed-of-light-in-a-vaccum, even if the actual light waves aren't always going that fast. Some have called it the "speed of gravity."

 

[ATOMonkey]

I am very curious to see if time really is relative. The only way we'll ever know for sure is to shoot someone off at faster than light speed, or send them through some gravity wells and see how "old" they are when they return.

My theory is that time is constant, and that everything is relative to time. You can sort the equations either way, which is the whole point of relativity, that something needs to be constant.

I think that how we experience time could be relative, but that time itself is constant.

If you really want to boil your brain, just imagine a transcendent being, outside of the natural world.

 

[Hohn]

I think that how we experience time could be relative, but that time itself is constant.

If you really want to boil your brain, just imagine a transcendent being, outside of the natural world.

It's easy if you try.

 

[Dead Duck]

Gravitational waves from black holes detected

I'm pretty sure my X-wife is responsible for this movement.

Last time I saw her she had her own orbiting moons.

 

[T.Lex]

I'm pretty sure my X-wife is responsible for this movement.

Last time I saw her she had her own orbiting moons.

Let me guess, she warped space-time so that every minute felt like a year?

 

[Dead Duck]

Let me guess, she warped space-time so that every minute felt like a year?

Yes!
Did you marry her too?

 

[rhino]

I am very curious to see if time really is relative. The only way we'll ever know for sure is to shoot someone off at faster than light speed, or send them through some gravity wells and see how "old" they are when they return.

My theory is that time is constant, and that everything is relative to time. You can sort the equations either way, which is the whole point of relativity, that something needs to be constant.

I think that how we experience time could be relative, but that time itself is constant.

If you really want to boil your brain, just imagine a transcendent being, outside of the natural world.

A number of experiments have been completed with previously synchronized atomic clocks with one fixed on Earth and the other orbiting at high speeds. The moving clocks are always behind their "stationary" counterparts, which is strong evidence supporting the idea of time dilation.

 

[Ericpwp]

Have they tried digital watches?

 

[Trigger Time]

A number of experiments have been completed with previously synchronized atomic clocks with one fixed on Earth and the other orbiting at high speeds. The moving clocks are always behind their "stationary" counterparts, which is strong evidence supporting the idea of time dilation.

So high speed slows time?
Sorry I usualy need the cliff notes version of this stuff to understand
Pictures and diagrams help too

 

[Spear Dane]

I am very curious to see if time really is relative. The only way we'll ever know for sure is to shoot someone off at faster than light speed, or send them through some gravity wells and see how "old" they are when they return.

My theory is that time is constant, and that everything is relative to time. You can sort the equations either way, which is the whole point of relativity, that something needs to be constant.

I think that how we experience time could be relative, but that time itself is constant.

If you really want to boil your brain, just imagine a transcendent being, outside of the natural world.

This has been proven by a huge body of experimentation and engineering, most visibly by the GPS system, which would quickly become useless without correcting for the time dilation experienced by the satellites.

 

[Hohn]

So high speed slows time?
Sorry I usualy need the cliff notes version of this stuff to understand
Pictures and diagrams help too

Yes, high speed slows time. Sort of.

What's really happening is that time is relative to one or the other. If I'm riding in a car at 60mph, that speed is relative to the earth's surface. Relative to the car, my speed is zero (I'm stationary in the seat). Relative to the Sun, my speed is thousands of MPH.

Being stationary is an illusion created by two objects moving at the same speed relative to the same thing. In reality, we are all hurtling through space at thousands of miles per hour. The sun itself is moving at high speed relative to SOME other star somewhere, right?

Is it the case that a high speed clock orbiting the earth is "slower"? Or is it that being closer to the gravity of earth actually speeds things up? Since we're talking about the two clocks relative to each other only, these could both be true. The space clock is "slow" only relative to the one on earth, and the terrestrial clock is "fast" only relative to the one in space.

A third clock at a different place in the universe might be faster than both, slower than both, or faster than one and slower than the other. And that "faster than one, slower than the other" isn't constant either. The "slow" clock might become the "fast" clock at different positions in the universe.

In other words, if you ranked three clocks in the order in which they appeared to be fast or slower, it would depend on on which clock you are using as reference, AND that ranking might not be consistent.