Big Bang and Alternatives

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Cindy
If BB is not a right answer, then what is preventing galaxies from getting closer to each other under effect of gavity?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">According to MM, the range of gravity (rG) is finite because of collisions among CG’s. In a 1996 article , TVF wrote: “The characteristic size of galaxy haloes and typical disk thickness imply that the characteristic scale distance for gravity, rG, may be about 2 kiloparsecs (kpc), which is about 6000 light-years.” That is less than 1/10th of the diameter of our galaxy. Our Sun is held by the gravity of other stars in our spiral arm; our spiral arm is held to the galaxy’s hub where it is attracted by gravity to the ends of other spiral arms.

In our small neck of the universe, galaxies tend to cluster in great walls surrounding great voids, forming a bubble-bath like structure. I suspect this happens because any galaxy will drift with zero acceleration so long as it remains outside the range of the gravity of other galaxies. When two galaxies approach one another closely enough to feel the gravity of stars around each other’s outer fringes, their courses change; if they collide, they may lose enough kinetic energy to remain close together. After many such collisions, clusters form; angular momentum tends to flatten the clusters; so the clusters drift like so many snow flakes. When clusters collide, they tend to stick edge to edge, forming great walls. The great walls may stick to each other edge to edge or edge to face, leaving great voids among them. One of the few remaining lone galaxies would drift across a great void with zero acceleration until it reaches a great wall. Collisions will eventually take away enough energy to prevent the galaxy from passing thru a great wall into the next void. Given sufficient time, all the galaxies end up in the great walls.

It might be possible to calculate the mean size of voids from the range of gravity or vice versa, though I’m sure other parameters must be considered. One might follow the example of a formula for the size of bubbles in a bubble bath, if such a formula has been discovered. Gravity might be equivalent to surface tension.

Whether the foam-like structure of great walls of galaxies extends to infinity is probably one of the great unknowables. Whether the foam formed as recently as the last 20 billion years, as claimed by BB, is probably another unknowable. I don’t "believe" one way or the other, but I am more comfortable with the idea that the foam we see in our telescopes is either the crest of a wave breaking on an immense ocean or the head on a glass of beer being chugged by a giant.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Cindy</i>
<br /><blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Thomas</i>
<br /><blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Cindy</i>
If BB is not a right answer, then what is preventing galaxies from getting closer each other under effect of gavity ?
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What gravity? In a homogeneous universe the mass distribution is the same in all directions and the force of gravity cancels to zero overall.

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Hi Thomas,

We know that in the univer, there are zones in which density of galaxies is high. Now we consider galaxies in such a zone. Are these galaxies getting closer under the effect of gravity ?

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Hi Cindy,

The galaxies are in general not getting closer in these regions because they also have a higher velocity there. The increased centrifugal force compensates for the increased gravitational force and hence the system is stable. This is basically the same for any stable structure in the universe, be it our solar system, star clusters, galaxies or galaxy clusters.

However, these local density variations are cosmologically irrelevant. According to the cosmological principle the large scale average of the matter density is the same everywhere in the universe and hence there can not be a resultant gravitational force as, according to Newton's third law, equal and opposite forces cancel.

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www.physicsmyths.org.uk
www.plasmaphysics.org.uk

[Jim] "Why do we need a model? I know TVF says without a model data is useless numbers. Is that true?"

Yes Jim, it is true. If you would take a little time to learn what others have discovered (this doesn't mean you have to believe that their interpretations are correct) you would realize that we all gripe about inadequate models (but not nearly as much as you do). Even the models we use to try to knock down other models have problems.

===

So, if models are such a pain in the ass, why do we keep using them? Because there is no alternative. If you think you have an alternative, and if you are right, you could be famous.

Regards,
LB

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Thomas</i>
What gravity? In a homogeneous universe the mass distribution is the same in all directions and the force of gravity cancels to zero overall.

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Hi Thomas,

I thought that the amount of material in the universe is finite. Therefore, the universe has a border. In the border regions, gravity does not cancel to zero.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Cindy</i>
I thought that the amount of material in the universe is finite. Therefore, the universe has a border. In the border regions, gravity does not cancel to zero.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

Cindy, you seem to be getting your basics from BB, but incorrectly. According to BB, every point in the finite-sized universe is the center of the expansion; so there are no border regions. That works mathematically because the BB universe has extra dimensions which our four-dimensional brains have difficulty modeling. Silicon-brained computers have no problem handling those extra dimensions, provided they are programmed correctly.

Unlike BB, MM allows for (but does not insist upon) the possibility of an infinite universe. If the MM universe is infinite in both size and time, with uniform distribution of mass (on the largest scales), then it also has no unique center nor border regions. However, under MM, it really doesn’t matter, because gravity doesn’t reach much beyond the fringes of each galaxy. Even if a galaxy were on the border of the universe, it would not be affect by gravity from galaxies much more than 6,000 light-years away. If no other galaxies are that close, it could simply drift slowly into the infinite void beyond.

Imagine a lighted sphere all of whose surface is uniformly bright; suspend that sphere in a black fog. When you are close to the sphere the brightness of its surface is constant but the solid-angle size is inversely proportional to the square of the distance, so the total brightness diminishes as the inverse square. When you move father away, the solid-angle size continues to decrease as the inverse square, but now the brightness of the surface is also growing dimmer because of the black fog. At a certain distance, the fog cuts off half of the light; twice that far, 3/4 of the light; so beyond that range, the total brightness diminishes as the inverse cube.

The MM describes a mass as a dark spot against a uniformly “bright” background of CG’s. This is like a negative image of the light sphere described above. Instead of a dark fog blocking the light, you have CG’s colliding and therefore making the dark spot appear brighter. At any rate, beyond the “range of gravity”, we should expect the effect of gravity to diminish much more rapidly than it does at closer range.

Consider two spherical galaxies of uniform density 60,000 ly in diameter with their centers 120,000 ly apart. Let’s assume that the range of gravity is 6,000 ly, (as TVF estimated in ‘96; and I’m assuming he means the distance at which you lose half of the strength). If you consider the whole mass to be concentrated at the center of each galaxy, then the pull of gravity between the galaxies is 2^20 times weaker than it would be if gravity had infinite range. That’s less than one millionth of the gravity predicted by BB. Doubling the distance to 240,000 ly would reduce the gravity by another factor &gt; 1,000,000; i.e., less than 10^-12 of the BB gravity. Therefore, if MM is correct, the gravity of our closest neighbors is all that matters; gravity holds the galaxy together only because the stars are strung together in continuous spiral arms; and the rest of the mass in the universe is irrelevant as far as gravity is concerned.

There is another explanation of the redshift - a gradual changing in Plancks constant. Then by E=hf, and conservation of energy the redshift results. Its described in www.gravity.uk.com (cosmological model section).

What do you think?

J.Hunter.