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View Full Version : Can things exist/develope without gravity?


ζ → 0
Jul1-09, 11:15 PM
Particles, life, etc.

negitron
Jul1-09, 11:37 PM
Highly doubtful. Without gravity, the only long-acting force is the electromagnetic force. Since (as far as we can tell) the matter in the universe tends toward electrically neutral, there would be very little in the way of attraction going on. Stars could not form and the universe would be a cold, cold place.

Chronos
Jul2-09, 12:52 AM
Particles are possible, life is not. Without planets, life is hugely improbable. Life needs soup from which to evolve. No gravity, no soup.

Rymer
Jul5-09, 11:18 PM
I had understood that the electromagnetic force was explainable by spin-like photon exchange (QED) and I've see other proposals that imply gravity might be explained by another photon exchange.

If so, it would appear, that the electromagnetic and gravity forces might come as a 'set'.

So I guess I'm saying that its unlikely to be able to have particles without some equivalent of gravity as well. Maybe not 'scaled' as we observe in our universe, but still both.

So I guess, I'm saying that existence will always include 'a gravity'?

Chronos
Jul6-09, 01:56 AM
Gravity is a given, life is not.

dylan123
Jul10-09, 12:41 PM
so does everything has mass?

Naty1
Jul11-09, 09:52 AM
so does everything has mass?

Probably so from the perspective of mass energy equivalence....maybe a perfect vacuum without external wave influences would not, assuming ground state conditions...

malawi_glenn
Jul11-09, 11:06 AM
... No gravity, no soup.

I like soup :biggrin:

Naty1
Jul11-09, 11:40 AM
So I guess I'm saying that its unlikely to be able to have particles without some equivalent of gravity

not likely so..... because the very early universe was a charged particle soup, a plasma early on...so as things cooled, electromagnetic attraction and,say the strong force, would pull ions together to form particles...but after that not much would happen...hydrogen and helium might form,just a few simple particles, but gravity is needed to pull such inert gases together and provide the potential energy to get nucler reactions (fission/fusion) started.... a few basic particles drifting far apart would seem to be rather inhospitable to the beginnings of life....

malawi_glenn
Jul11-09, 11:44 AM
not likely so..... because the very early universe was a charged particle soup, a plasma early on...so as things cooled, electromagnetic attraction and,say the strong force, would pull ions together to form particles...but after that not much would happen...hydrogen and helium might form,just a few simple particles, but gravity is needed to pull such inert gases together and provide the potential energy to get nucler reactions (fission/fusion) started.... a few basic particles drifting far apart would seem to be rather inhospitable to the beginnings of life....

No gravitational attraction is not needed for Big Bang Nucleosynthesis. However, gravity is needed to stellar formation.

Rymer
Jul11-09, 12:11 PM
No gravitational attraction is not needed for Big Bang Nucleosynthesis. However, gravity is needed to stellar formation.
Thank you -- a very interesting point.

Rymer
Jul11-09, 12:38 PM
Gravity is a given, life is not.
And God said -- Let there be General Relativity.

(sorry couldn't resist upon reading -- after the Douglas Adams quote.)

malawi_glenn
Jul11-09, 12:39 PM
And God said -- Let there be General Relativity.

(sorry couldn't resist upon reading -- after the Douglas Adams quote.)

Amen :-)