Galaxy collisions

There is not much difference to individual stars during galaxy collisions in either model. Either way, stars are inflienced significantly only by other stars they happen to pass very close to. The gravity of individual stars at normal interstellar distances and passing speeds is rather negligible.

As for the gross behavior of galaxy shapes in the two models, a paper in the Australian Astronomical Society journal about 11 years ago compared the two and found that, of all possible gravity laws, only inverse square and inverse linear (an approximation of MM) give results that resemble reality. And of those two models, inverse linear worked better. -|Tom|-

assuming the inverse linear - once the collision (initial) has passed the two galaxies should not slowdown and 'fall back' towards each other (on a grand scale)?

Some simulations I saw seems to indicate that they would speed up as they approach and slow down when they leave each other to the point when they will start falling back again. The end result would be an eventual merger of the two core systems over millions of years.

I take it you agree this would not happen if the inverse linear law is working. After the collision the two galaxies (or remnants) would continue on a more or less straight path away from each other - never to meet again in a significant time.

Rudolf

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Rudolf</i>
<br />assuming the inverse linear - once the collision (initial) has passed the two galaxies should not slowdown and 'fall back' towards each other (on a grand scale)?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Interacting galaxies experience something called "dynamical friction", caused by close star encounters that can cause forward-moving stars to zip around one another and become backward-moving stars. This slows the forward motion of the galaxies as they encounter one another. It is a process not unlike trying to plow through molasses.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Some simulations I saw seems to indicate that they would speed up as they approach and slow down when they leave each other to the point when they will start falling back again. The end result would be an eventual merger of the two core systems over millions of years.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">The slow-down due to dynamical friction is a real effect that must occur in either model.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">I take it you agree this would not happen if the inverse linear law is working. After the collision the two galaxies (or remnants) would continue on a more or less straight path away from each other - never to meet again in a significant time.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Besides dynamical friction, the Meta Model indicates that the space between galaxies is filled with elysium, and elysium has mass too. So galaxies in clusters would continue to experience local forces from elysium within a few kiloparsecs, even after they have separated from one another by more than a few kiloparsecs.

The net is that galaxy mergers are less likely in MM than in BB, but are still a regular part of galaxy evolution. -|Tom|-

This was what I was trying to ask: After the initial collision and they have seperated the few kiloparsecs as you stated, would they still experience any attraction force towards each other?

A while ago I saw a galaxy crash simulator ( burro.astr.cwru.edu/JavaLab/GalCrashWeb/ ) that showed how they (galaxies) keeps on falling back towards each other, even after they have seperated thousands of lightyears. This in my view seem wrong as after they have seperated far enough they will not fall 'back' again.

Are there any other objects that have the same collision signature as galaxies that we can examine (in a human lifetime hopefully)?

Rudolf

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Rudolf</i>
<br />This was what I was trying to ask: After the initial collision and they have seperated the few kiloparsecs as you stated, would they still experience any attraction force towards each other?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">The centers would not exert any attraction, but the chain of disks of stars, gas, and elysium out to great distances might still interact.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">A while ago I saw a galaxy crash simulator ... that showed how they (galaxies) keeps on falling back towards each other, even after they have seperated thousands of lightyears. This in my view seem wrong as after they have seperated far enough they will not fall 'back' again.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">In an inverse-square gravity law, if the relative speed drops below escape speed, then that is exactly what must happen.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Are there any other objects that have the same collision signature as galaxies that we can examine (in a human lifetime hopefully)?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Maybe globular clusters, if we ever discover a case of two colliding globulars. -|Tom|-

Just to clarify, I do understand that the centers (and opposite parts) won't experience any attraction until they come into the few kpc range.

If elysium have mass and it tends to be concentrated around 'big' objects (any object actually) then an objects gravitational infuence is not dependant on its own mass only but also of the elysium that surrounds it?? That would mean calculating gravitational influences must take this in considderation - right? This could mean a whole other way of thinking about gravity.

Rudolf