# The Naked Scientists Forum

### Author Topic: Does all matter in the universe bound to each other gravitationally ?  (Read 3233 times)

#### asterisk

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##### Does all matter in the universe bound to each other gravitationally ?
« on: 11/05/2012 11:25:30 »
like moon gravitationally bound to earth, earth to sun,sun to milky way ,milkyway to andromeda....likewise i think all matter in universe would be connected to eachother if we could get get to see the bigger picture of universe  ?
« Last Edit: 11/05/2012 12:17:50 by asterisk »

#### Pmb

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #1 on: 11/05/2012 12:35:12 »
like moon gravitationally bound to earth, earth to sun,sun to milky way ,milkyway to andromeda....likewise i think all matter in universe would be connected to eachother if we could get get to see the bigger picture of universe  ?
Yes. That seems to be the case.

#### Phractality

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #2 on: 11/05/2012 22:37:32 »
We can't prove that Newton's law of gravity is perfect at all distances. If it is, the effect of gravity diminishes by the inverse square, making it extremely small at extreme distances. Beyond some distance, dark energy makes gravity inconsequential.
We also can't prove that the universe is finite in size. If it is infinite, then the effect of gravity becomes zero at infinite distance.
We also can't prove that the force of gravity propagates at finite speed. Many scientists claim that gravity force propagates at the speed of light, which make it zero at the Hubble limit.
I believe the foamy texture of galaxy clusters, shown in your attached image, minimizes gravitational potential energy on the scale of about 10^24 m. Beyond that, there don't seem to be any gravitationally bound structures.
I don't think the answer to your question is knowable, but I suspect the answer might be NO.
Proponents of big bang theory may disagree with me. They refuse to admit the long list of things they're assuming.

#### Pmb

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #3 on: 11/05/2012 23:45:27 »
We can't prove that Newton's law of gravity is perfect at all distances.
When I said, Yes. It seems that way. that's what I meant. I think this is one of those things that we may never know.

#### asterisk

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #4 on: 12/05/2012 07:23:31 »

I believe the foamy texture of galaxy clusters, shown in your attached image, minimizes gravitational potential energy on the scale of about 10^24 m. Beyond that, there don't seem to be any gravitationally bound structures.

I don't think the answer to your question is knowable, but I suspect the answer might be NO.

Proponents of big bang theory may disagree with me. They refuse to admit the long list of things they're assuming.

i think the proponents of big bang agree with you because it says in big bang theory that 'space itself expands' only between unbound structures , that is why i specifically asked this question  :) if all matter in the universe is bounded farther galaxies doesn't recede faster than speed of light as proposed by big bang cosmology
« Last Edit: 12/05/2012 07:25:12 by asterisk »

#### Pmb

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #5 on: 12/05/2012 16:09:25 »
i think the proponents of big bang agree with you because it says in big bang theory that 'space itself expands' only between unbound structures ...
Where did you get that idea from?

#### Phractality

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #6 on: 12/05/2012 19:48:27 »
I think the proponents of big bang agree with you because it says in big bang theory that 'space itself expands' only between unbound structures....
I think that is a distortion of the notion that space expands everywhere, but all the new space ends up between gravitationally bounded structures. We don't see gravitationally bounded structures being stretched internally because the new space created within them oozes out into the surrounding space. We see the voids of the cosmic foam growing and the galaxies surrounding them being stretched farther apart from one another.
That leads me to ask whether those walls of galaxies can be stretched beyond the limit of their tensile strength. I believe the gravitational (or unknown force) bonds between neighboring galaxies eventually rupture. Cosmic-foam bubbles pop like the head on a glass of beer, resulting in the many colliding galaxies that have been photographed by HST. (Sorry if I'm introducing new theory. I'll refrain from going any farther with that idea, here.)
... that is why i specifically asked this question  :) if all matter in the universe is bounded farther galaxies doesn't recede faster than speed of light as proposed by big bang cosmology.
The idea that galaxies beyond the Hubble limit recede faster than light is not limited to big bang cosmology. I think the idea that the universe is bigger than the Hubble sphere comes from inflationary big bang and from non-big-bang infinite universe cosmology.
If the universe is finite in size, then it must be gravitationally bound. If it is infinite in size, then the question is unanswerable.

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#### acsinuk

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #7 on: 20/05/2012 12:52:36 »
Shrunk
Hi A +2Ps
Surely, gravity force is only of quarter importance as the WMAP survey reveals that 74% of universe is dark energy force.  So the universe has a further force that is four times as powerful as gravity which is almost certainly 3D electro-magnetic!
CliveS

#### yor_on

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##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #8 on: 22/05/2012 07:53:51 »
Gravity is what defines the universe. All uniformly moving objects follows geodesics as far as I know? To assume that gravity 'stopped' would also mean that the geodesics would 'stop'. It is the metric of SpaceTime.

#### The Naked Scientists Forum

##### Re: Does all matter in the universe bound to each other gravitationally ?
« Reply #8 on: 22/05/2012 07:53:51 »