Leave these fields empty (spam trap):
You can leave this blank to post anonymously, or you can create a Tripcode by using the format Name#Password
[i]Italic Text[/i]
[b]Bold Text[/b]
[spoiler]Spoiler Text[/spoiler]
>Highlight/Quote Text
[pre]Preformatted & Monospace Text[/pre]
[super]Superset Text[/super]
[sub]Subset Text[/sub]
1. Numbered lists become ordered lists
* Bulleted lists become unordered lists


420chan is Getting Overhauled - Changelog/Bug Report/Request Thread (Updated July 26)

Gravity Question

- Mon, 15 Dec 2014 11:28:17 EST 415JX8nG No.54821
File: 1418660897305.jpg -(18309B / 17.88KB, 450x450) Thumbnail displayed, click image for full size. Gravity Question
Would two colliding gravitational waves exert a tiny force against each other?

If they did at distances where the universe becomes homogenized, could the cumulative force of colliding gravitational waves of the rest of the universe overcome the weak attraction of gravity?

This isn't against dark energy, I was just wondering if it could be a contributing factor.
Chushiro Hayashi - Mon, 15 Dec 2014 11:35:44 EST ksAXy5yQ No.54822 Reply
The answer is...

We still have no fucking clue.
Pierre-Simon Laplace - Mon, 15 Dec 2014 21:30:42 EST jOF47H5F No.54825 Reply
Two forces of equal magnitude but opposite directions cancel out, so there would be no gravitational force. But if there really are gravitational waves of this sort (still being researched), and they interact in patterns of constructive and destructive forces, then it does seem possible, though highly unlikely, that enough gravitational waves would converge on the same distant point to at least be noticeable without the use of precision instruments.
Ejnar Hertzprung - Tue, 16 Dec 2014 00:51:40 EST 415JX8nG No.54827 Reply
i know it's a calculable thing with relativity, if someone around here knows the physics.

I guess another way of asking the question would be, do two colliding gravitational waves cause space (and time) to expand between them?

said waves of equal magnitude cancel out, but that would only be a specific radius (roughly) of your section of the universe, where the threshold of balance between the force of waves is equal.

I guess another question to ask would be do colliding gravitational waves increase the space (and time) between objects noticeably on super-galactic levels?
Ejnar Hertzprung - Tue, 16 Dec 2014 00:53:14 EST 415JX8nG No.54828 Reply
sorry for that retard double statement, I'm drunk and high, and cool
Caroline Herschel - Tue, 16 Dec 2014 04:56:03 EST Ncnb3OJc No.54829 Reply
1418723763789.gif -(41331B / 40.36KB, 150x150) Thumbnail displayed, click image for full size.
Gravitational waves don't have a longitudinal component, so they don't cause expansion or contraction of space along the direction of propagation. They cause expansion or contraction perpendicular to the direction of propagation. Pic related, it's what you'd see if a very strong gravitational wave traveled along the line from your screen to your face. It simultaneously expands and contracts in such a way that any area is only deformed, not increased or decreased. There is no unbalanced force, thus, it can't contribute to the metric expansion of spacetime.

Two gravitational waves would not collide, they would constructively or destructively interfere. That means that in some places, the effect in the gif would be amplified, while cancelled out in other places. Interference still wouldn't create unbalanced forces.

Another argument against it being related to the expansion of spacetime is that the strength of gravitation waves are inversely proportional to the distance from the source. The expansion of spacetime, on the other hand, is most significant in areas of low gravity. Galaxies are receding, but not falling apart. Binary stars (which are likely generators of gravity waves) don't repulse other objects or binary stars.

Finally, keep in mind that gravitational waves are generated only by accelerating objects, they only propagate changes in a gravitational field, they're not the carriers of gravity or the dual of gravitons.

Disclaimer: I'm not a physicist nor do I understand the math. This is just what I picked up reading about the topic.
Bruon Rossi - Sun, 28 Dec 2014 22:33:12 EST 2uBuMclp No.54861 Reply
weak or strong gravitational waves exert a force against each other. thats why while you are being pulled to the earth the earth is also being pulled toward you.

Report Post
Please be descriptive with report notes,
this helps staff resolve issues quicker.