## A few bones to chew on

Message boards : Science (non-SETI) : A few bones to chew on
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Jeff

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Message 761294 - Posted: 31 May 2008, 14:32:50 UTC

It is known that as an object accelerates, its relative mass increases, so that brings up a question.

If an object was moving at 99% of the speed of light, would the relativistic mass have any affect on the gravitational field of the object?

If so, what would be the impact on the local gravitational field at this point?
ID: 761294 ·
Odysseus
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Message 761564 - Posted: 1 Jun 2008, 3:28:12 UTC - in response to Message 761294.

It is known that as an object accelerates, its relative mass increases, so that brings up a question.

If an object was moving at 99% of the speed of light, would the relativistic mass have any affect on the gravitational field of the object?

Yes, but thereâ€™s been some debate over the notion of â€œrelativistic massâ€ itself: see the Usenet Physics FAQ on the subject. At any rate, according to general relativity the mass-equivalent of energy, whatever it may be called, gravitates. An object passing you at 0.99c would appear to exert about seven times the gravitational force that it would if at rest.
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Knightmare
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Message 761572 - Posted: 1 Jun 2008, 4:25:08 UTC

* MUST remind myself not to look in here *
from silent stone,
Death is preordained

Calm Chaos Forums : Everyone Welcome
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William Rothamel

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Message 761596 - Posted: 1 Jun 2008, 7:07:03 UTC - in response to Message 761294.

It is known that as an object accelerates, its relative mass increases, so that brings up a question.

If an object was moving at 99% of the speed of light, would the relativistic mass have any affect on the gravitational field of the object?

If so, what would be the impact on the local gravitational field at this point?

Jeff,

Interesting question--
I'll answer with a a related question. Each planet in the universe is moving --moving relative to many frames of reference--We are moving in orbit around the sun. The sun is moving around the galaxy. The galaxy is also moving.

So my question is if we are moving fast (and we are) and this motion affects our gravitational field then how can there be a universal gravitational constant (which there is) ? Is the infinite mass at near light speed really mass in the sense of Newton's equation or is it only to reflect the force (energy) required to go a little faster as a consequence of Einstein's Special Relativity.

Bill
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ML1
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Message 761650 - Posted: 1 Jun 2008, 12:47:31 UTC - in response to Message 761572.

* MUST remind myself not to look in here *

A few beers help!

For some real fun heavy-weight nightmares, take a look on this thread! I'm still gravitating on that one from months ago!!

Cheers,
Martin

See new freedom: Mageia5
See & try out for yourself: Linux Voice
The Future is what We all make IT (GPLv3)
ID: 761650 ·
ML1
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Message 761651 - Posted: 1 Jun 2008, 12:49:10 UTC - in response to Message 761564.

... An object passing you at 0.99c would appear to exert about seven times the gravitational force that it would if at rest.

I wonder if e@h would 'see' that one for sure?!

Keep searchin',
Martin
See new freedom: Mageia5
See & try out for yourself: Linux Voice
The Future is what We all make IT (GPLv3)
ID: 761651 ·

Message boards : Science (non-SETI) : A few bones to chew on