Infinite Gravity?

[CramBoom]

I am by no means an expert on this, so I'm probably completely off. But, if our universe was infinite, wouldn't there be infinite gravity all around us? I know gravity is weaker the farther away you are from the source, but an infinite universe should have an infinite amount of massive bodies, therefore there would be an infinite amount of gravity everyone. Since gravity is uniform everywhere, it will cancel itself out, and voila, no gravity. Doesn't this factor rule out the possibility of an infinite universe? I am sure scientists already thought of this, so why am I wrong? Thanks.

[Endercreeper01]

Well gravity is proportional to the inverse if distance sqared, so then the other stuff would cancel out but then, As you would approach a mass then it gets bigger and bigger by 1/r^2, so it would have an effect

Well gravity is proportional to the inverse if distance sqared, so then the other stuff would cancel out but then, As you would approach a mass then it gets bigger and bigger by 1/r^2, so it would have an effect

[CramBoom]

Well gravity is proportional to the inverse if distance sqared, so then the other stuff would cancel out but then, As you would approach a mass then it gets bigger and bigger by 1/r^2, so it would have an effect

Well gravity is proportional to the inverse if distance sqared, so then the other stuff would cancel out but then, As you would approach a mass then it gets bigger and bigger by 1/r^2, so it would have an effect

But infinity is such a powerful concept. Even though gravity is inversely proportional to the distance squared, an infinite amount of massive bodies kind of counters that in a way. Or am I terribly mistaken?

[Delta1212]

Infinite mass in all directions would balance out, though.

[swansont]

Infinite mass in all directions would balance out, though.

Yes. It's a vector.

 

If you have a uniform mass distribution, the only net effect will be the mass enclosed inside a volume, not outside of it. e.g. if you had some giant sphere of mass and you were a distance R from the center, only the mass out to R will contribute to your attraction to the origin. All of the mass outside has no net effect. This Gauss's law.

 

http://en.wikipedia.org/wiki/Gauss's_law_for_gravity

[Ihcisphysicist]

Ok you are implying that infinite gravity would be universal in the entire universe, but look at it this way even though in earth itself when an ant is droped, it doesn't exhibit much gravititional pull from earth compared to human and other such. Thus mass and perspective of the matter to the universe definetly influence gravity.

But i somehow get your point. If the universe is infinity, means no end then it triggers the lost quest for the beggining. "without beggining there would be no end", its only logical.

[Delbert]

If I've understood all this correctly, it seems you're looking at the universe as a whole. And as such the total may well be the same as what I understand to be the total amount of energy in the universe adding up to zero.

 

As for gravity, I'd have thought the gravity at any given point to be the sum of the gravity of the surrounding objects. We see this everyday with the tides; and doubtless, we'll be a tad lighter on a similar regular basis. But anything farther away past the solar system, the effect will be difficult to measure - if at all. So we experience the resulting effect.

 

Then there's the quantum effect. Presumably at a sufficient distance from an object such that the gravitational force is less that a graviton, supposedly it must therefore be ineffective to the point of zero at other parts of the universe. So, objects at a vast enough distant won't be part of the calculation. The conclusion being that there's no universal total.

[Delta1212]

If I've understood all this correctly, it seems you're looking at the universe as a whole. And as such the total may well be the same as what I understand to be the total amount of energy in the universe adding up to zero.

 

As for gravity, I'd have thought the gravity at any given point to be the sum of the gravity of the surrounding objects. We see this everyday with the tides; and doubtless, we'll be a tad lighter on a similar regular basis. But anything farther away past the solar system, the effect will be difficult to measure - if at all. So we experience the resulting effect.

 

Then there's the quantum effect. Presumably at a sufficient distance from an object such that the gravitational force is less that a graviton, supposedly it must therefore be ineffective to the point of zero at other parts of the universe. So, objects at a vast enough distant won't be part of the calculation. The conclusion being that there's no universal total.

Assuming gravitons exist, of course. The lack of a quantum theory of gravity is a problem for taking quantum effects into account.

[doG]

I am by no means an expert on this, so I'm probably completely off. But, if our universe was infinite, wouldn't there be infinite gravity all around us?

Not necessarily. Infinite gravity would require infinite mass but an infinite universe need not be full of infinite mass...

[Deidre]

If gravity is infinite, why couldn't time be considered infinite? Since, the inception of time is attached to the occurence of the Big Bang, and thus...how could anything be infinite?

[Ihcisphysicist]

If gravity is infinite, why couldn't time be considered infinite? Since, the inception of time is attached to the occurence of the Big Bang, and thus...how could anything be infinite?

But who actually can tell for sure that big bang was the cause for the expandation of our universe. Its all in our head and nothing could actually be what we may think it is.