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jwestern
2009-Dec-01, 03:05 PM
I am new to the forum and find it enjoyable and informative reading the discussion threads. As I am new, this topic may have been covered and discussed earlier, but I could not find a discussion link. So I apologize in making errors in getting familiar using the site.

In an astronomy TV program or podcast I recently saw, there was a comment that the gravity interaction between planets, galaxies’, etc. is instantaneous. Gravity interactions are faster than the speed of light...all mass in the universe is in constant contact with all other mass in the universe.

This topic intrigues me as I never before considered or thought about the time it takes for the gravity of one mass to communicate with the gravity of another mass. I ask for your thoughts on the topic and any references on the subject you could recommend. Thanks.

Best Regards...............Jeff :question:

Jens
2009-Dec-02, 03:56 AM
You may have misunderstood some subtlety, but gravity apparently propagates at close to the speed of light, not instantaneously. This has been discussed from time to time, and actually there is another thread in Q&A on the very subject that is at the top of active threads. You might try reading through that for some answers.

cosmocrazy
2009-Dec-02, 07:27 AM
Welcome to BAUT Jeff

Yes as Jens already stated the current accepted mainstream theory is that gravity propagates not faster than C, as this would violate causality (information transmitted faster than light could imply time travel, e.g the Grandfather paradox)

Its been discussed already on this thread - http://www.bautforum.com/space-astronomy-questions-answers/97380-speed-gravity.html

undidly
2009-Dec-02, 10:55 AM
I am new to the forum and find it enjoyable and informative reading the discussion threads. As I am new, this topic may have been covered and discussed earlier, but I could not find a discussion link. So I apologize in making errors in getting familiar using the site.

In an astronomy TV program or podcast I recently saw, there was a comment that the gravity interaction between planets, galaxies’, etc. is instantaneous. Gravity interactions are faster than the speed of light...all mass in the universe is in constant contact with all other mass in the universe.

This topic intrigues me as I never before considered or thought about the time it takes for the gravity of one mass to communicate with the gravity of another mass. I ask for your thoughts on the topic and any references on the subject you could recommend. Thanks.

Best Regards...............Jeff :question:

If the gravitational interaction was instantaneous then there would be no
gravitational waves.
Have we detected gravitational waves?.
Nuff said.
I'm off to ATM.

Jens
2009-Dec-02, 11:10 AM
If the gravitational interaction was instantaneous then there would be no
gravitational waves.
Have we detected gravitational waves?.
Nuff said.

Assuming you're not joking: great logic. We can use the same:

If Olof Palme (PM of Sweden) hadn't been murdered, there would be no murderer. Have we found a murderer? Enough said! Palme is still alive!

undidly
2009-Dec-02, 11:35 AM
Assuming you're not joking: great logic. We can use the same:

If Olof Palme (PM of Sweden) hadn't been murdered, there would be no murderer. Have we found a murderer? Enough said! Palme is still alive!

We found a body .He is dead.

I do not think Gravitational interactions are instantaneous but may be very fast.

This thread is becoming ATM.

jwestern
2009-Dec-02, 08:46 PM
Thanks to all for setting me straight and getting me to an existing thread on the topic. I appreicate the quick responses.

Best Regards..............Jeff

Cougar
2009-Dec-02, 08:58 PM
If the gravitational interaction was instantaneous then there would be no gravitational waves.
Have we detected gravitational waves?.
Nuff said.

Jens' point about your logic was apparently lost on you. Our current inability to successfully detect gravitational waves proves nothing about whether they exist or not.

In fact, there is strong support for their existence. A couple guys got Nobel prizes (http://nobelprize.org/nobel_prizes/physics/laureates/1993/press.html) by finding this strong support...

undidly
2009-Dec-03, 09:55 AM
Jens' point about your logic was apparently lost on you. Our current inability to successfully detect gravitational waves proves nothing about whether they exist or not.

In fact, there is strong support for their existence. A couple guys got Nobel prizes (http://nobelprize.org/nobel_prizes/physics/laureates/1993/press.html) by finding this strong support...

""Jens' point about your logic was apparently lost on you""

YES that is correct.Lost on me.

""Our current inability to successfully detect gravitational waves proves nothing about whether they exist or not.""

Same as the æther.

Nobel shmobel.
All accelerating systems lose energy to the other mass in the universe,
gravitational waves or not.

korjik
2009-Dec-03, 10:35 PM
""Jens' point about your logic was apparently lost on you""

YES that is correct.Lost on me.

""Our current inability to successfully detect gravitational waves proves nothing about whether they exist or not.""

Same as the æther.

Nobel shmobel.
All accelerating systems lose energy to the other mass in the universe,
gravitational waves or not.

Wow, too bad no one thought of that before. Say like every astronomer who worked on the Mars orbit problem before general relativity.

Oh, wait, they did.

undidly
2009-Dec-03, 11:12 PM
Wow, too bad no one thought of that before. Say like every astronomer who worked on the Mars orbit problem before general relativity.

Oh, wait, they did.

What was the Mars orbit problem?.

I remember a Mercury orbit problem and the explanation.
Good GR stuff.Very interesting.

korjik
2009-Dec-04, 08:38 AM
Mercury.

Some of us shouldnt post when our blood sugar is low.

:)

thomheg
2009-Dec-06, 05:43 PM
I recently saw, there was a comment that the gravity interaction between planets, galaxies’, etc. is instantaneous. Gravity interactions are faster than the speed of light...all mass in the universe is in constant contact with all other mass in the universe.

As I see it -and this is my personal point of view - this statement is correct.
(But I don't want to be moved with my statement to ATM again, so let me call it speculation.)
If what we call matter is a structure in an invisible but elastic medium, than there is not need for gravity to move. What does move are the objects like planets. If you push on than medium, the change would travel with a certain speed. But planets do not move in this way. They are like vortices, that this medium guides through its properties on a certain path.
If you could push a planet away from that path, the other objects would 'feel' that too, but delayed by c, because what travels is a change, like light represents change.
Since the planets orbits represent stability (otherwise they wouldn't be there) they don't need to pass anything.
The connection itself -if you wish- has infinite velocity, because it doesn't move (it has no time component).

pzkpfw
2009-Dec-06, 07:44 PM
A reminder to everyone that the Q&A forum is intended to be a resource providing mainstream answers to questions. It's not the place to introduce ATM claims or to argue against mainstream science.