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Author Topic: Could there be both matter and antimatter galaxies?  (Read 3359 times)

Offline norcalclimber

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Many scientists have been telling us that when the Big Bang occurred, almost equal amounts of antimatter was created as matter.  But something happened which caused a very tiny more number of "normal" particles to survive while all of the antimatter was annihilated. This is referred to as baryogenesis, but how do they know this though?  We observe lots of matter in the universe, in the form of galaxies and stars, but would we even be able to see antimatter stars or galaxies?  How would antimatter stars be affected by gravity, or more specifically, what direction would they bend space/time?  What if we imagine the universe is affected by matter/antimatter poles?  As in, all matter would be very slightly drawn towards say the north pole, and all antimatter would be very slightly drawn to the south pole(aspect of gravity?)of the universe.  Wouldn't that have caused very slightly more of each form of matter to exist in each half of the universe?  If antimatter bends space/time opposite to our own, would we be able to "see" the antimatter? Or would it be obscured by the curvature of space/time?  If photons aren't really affected by the curvature of space/time, would we even be able to "see" antiphotons? Would antiphotons just cancel out photons, therefore making them "invisible"?

Could it be possible that at cooler temperatures/slower speeds, that matter and antimatter would actually orbit each other by opposing gravitational pressures, i.e. regions of higher/lower gravitational pressure caused by opposing curvature of space/time encouraging a path of least resistance?

If so, could it be that quasars are actually young galaxies, where matter is orbiting antimatter with the subsequent annihilation at the core igniting fusion events and birthing stars?  If the initial galactic collision of matter/antimatter very slightly favored matter to antimatter, wouldn't that mean that over time the balance would continue to shift in favor of matter, as out of each matter/antimatter collision very slightly more of the matter created would be expected to survive than the antimatter?

Could our galaxy be middle-aged, where the balance of matter to antimatter has shifted far in favor of matter?  Is that the real reason some "black holes" at the center of some galaxies have seemed to have gone dormant...because they are old, and simply destroyed nearly all of the antimatter at the center?

If all this were true, would opposing gravitational pressures from a matter/antimatter galaxy cause the resultant galaxy to form in a disc-like formation?

Also, if you looked at the flow of space/time across orbiting matter/antimatter particles, wouldn't it look like a "wave", with peaks and troughs?  Would that flow cause "waves" in all particles affected by that flow?

If space/time is a fluid, does galactic movement create a "current" in space/time?  Perhaps like whirlpool?  Does the pattern of gamma ray emission from "black holes" at the center of some galaxies resemble two opposing whirlpools because the antimatter gravitation is opposed to the matter gravitation and the particles are meeting at a midpoint between a peak and a trough?

Could the universe appear to be expanding merely because different galaxies have different surface areas and are affected differently by "currents" or "flows" within space/time?
« Last Edit: 18/02/2010 18:23:04 by norcalclimber »


 

Offline Farsight

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Re: Could there be both matter and antimatter galaxies?
« Reply #1 on: 15/02/2010 12:35:32 »
Many scientists have been telling us that when the Big Bang occurred, almost equal amounts of antimatter was created as matter. But something happened which caused a very tiny more number of "normal" particles to survive while all of the antimatter was annihilated. This is referred to as baryogenesis, but how do they know this though?
Actually they don't. This is one of the "unsolved problems of physics", see http://en.wikipedia.org/wiki/List_of_unsolved_problems_in_physics and http://en.wikipedia.org/wiki/Baryon_asymmetry. Pair production makes it fairly clear that you can't create matter without creating antimatter, but it isn't quite right to say it was all created at the same instant. Note the line in the wiki article where it says "there is no experimental evidence of an imbalance in the creation rates of matter and antimatter."     

We observe lots of matter in the universe, in the form of galaxies and stars, but would we even be able to see antimatter stars or galaxies?
Yes, we'd be able to see them. Antimatter isn't that different to ordinary matter.

How would antimatter stars be affected by gravity, or more specifically, what direction would they bend space/time?
They'd be affected the same as ordinary matter, and the space-time curvature would be as per ordinary matter.

What if we imagine the universe is affected by matter/antimatter poles? As in, all matter would be very slightly drawn towards say the north pole, and all antimatter would be very slightly drawn to the south pole (aspect of gravity?) of the universe.
I don't like that idea. The electromagnetic force is far more powerful than gravity. Positively charged particles are affected by electromagnetic fields in a different fashion to negatively charged particles, irrespective of whether they're matter or antimatter. And matter and antimatter are affected by gravity the same way, and cause gravity the same way. 

Wouldn't that have caused very slightly more of each form of matter to exist in each half of the universe? If antimatter bends space/time opposite to our own, would we be able to "see" the antimatter? Or would it be obscured by the curvature of space/time?"?
I guess I'm saying no here.

If photons aren't really affected by the curvature of space/time, would we even be able to "see" antiphotons? Would antiphotons just cancel out photons, therefore making them "invisible"?
Photons map out the curvature, and there are no antiphotons. Or I should say "the photon is its own antiparticle". Check out electron-positron annihilation, the result is just two 511keV photons.

Could it be possible that at cooler temperatures/slower speeds, that matter and antimatter would actually orbit each other by opposing gravitational pressures, i.e. regions of higher/lower gravitational pressure caused by opposing curvature of space/time encouraging a path of least resistance?
Sorry norcal, but no. Energy causes gravitational pressure, whether its configured as matter, antimatter, light, or anything else.

If so, could it be that quasars are actually young galaxies, where matter is orbiting antimatter with the subsequent annihilation at the core igniting fusion events and birthing stars? If the initial galactic collision
Quasars are associated with galaxy formation, but they don't consist of matter annihilating antimatter. If they did we'd see characteristic wavelengths, such as 2.426 x 10-12m. We do see this elsewhere, and hence we know that positrons are being annihilated with electrons. See for example http://www.cesr.fr/~jurgen/science/allsky511keV.html.

...of matter/antimatter very slightly favored matter to antimatter, wouldn't that mean that over time the balance would continue to shift in favor of matter, as out of each matter/antimatter collision very slightly more of the matter created would be expected to survive than the antimatter?
Now you're talking. If you have a constant creation of matter and antimatter particle pairs along with a way to destroy any one individual particle by "throwing it back into the melting pot", you can get a what's called a stability tip.

Could our galaxy be middle-aged, where the balance of matter to antimatter has shifted far in favor of matter? Is that the real reason some "black holes" at the center of some galaxies have seemed to have gone dormant...because they are old, and simply destroyed nearly all of the antimatter at the center?
No, the shift would have occured very early on around the time of the big bang. 

If all this were true, would opposing gravitational pressures from a matter/antimatter galaxy cause the resultant galaxy to form in a disc-like formation?

Also, if you looked at the flow of space/time across orbiting matter/antimatter particles, wouldn't it look like a "wave", with peaks and troughs?  Would that flow cause "waves" in all particles affected by that flow?

If space/time is a fluid, does galactic movement create a "current" in space/time? Perhaps like whirlpool?  Does the pattern of gamma ray emission from "black holes" at the center of some galaxies resemble two opposing whirlpools because the antimatter gravitation is opposed to the matter gravitation and the particles are meeting at a midpoint between a peak and a trough?

Could the universe appear to be expanding merely because different galaxies have different surface areas and are affected differently by "currents" or "flows" within space/time?
Not really, norcal. Light is a transverse wave, so space is more like a ghostly intangible solid rather a fluid, and whilst your whirlpool is essentially gravitomagnetics, you're stretching things a bit far here. IMHO it's good to kick things around, but I'd say antimatter is rather more mundane than you think.
 

Offline norcalclimber

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Re: Could there be both matter and antimatter galaxies?
« Reply #2 on: 15/02/2010 17:51:52 »
Thanks, I figured there was probably something I wasn't quite understanding.  I appreciate you taking the time to respond :)
 

Offline norcalclimber

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Re: Could there be both matter and antimatter galaxies?
« Reply #3 on: 15/02/2010 18:46:00 »
Quasars are associated with galaxy formation, but they don't consist of matter annihilating antimatter. If they did we'd see characteristic wavelengths, such as 2.426 x 10-12m. We do see this elsewhere, and hence we know that positrons are being annihilated with electrons. See for example http://www.cesr.fr/~jurgen/science/allsky511keV.html.

So we definitely see antimatter(or at least positrons) at the center of our galaxy?
They'd be affected the same as ordinary matter, and the space-time curvature would be as per ordinary matter.

I'm sure you are correct, but how do we know this?  I was under the impression we have only observed extremely small quantities of antimatter, and only at extremely high speeds.  It only makes sense that antimatter would be affected by gravitational pressure, and we have only observed it deep in our own gravity well.  If we have only viewed small particles, and those particles don't have enough mass to create a noticeable curvature of space time, how do we know that say an antimatter star doesn't curve space opposite to our own?  If it did, and photons map the curvature of space, wouldn't we be unable to see it?

Quasars are associated with galaxy formation, but they don't consist of matter annihilating antimatter. If they did we'd see characteristic wavelengths, such as 2.426 x 10-12m. We do see this elsewhere, and hence we know that positrons are being annihilated with electrons. See for example http://www.cesr.fr/~jurgen/science/allsky511keV.html.

I thought gamma radiation was evidence of electron/positron annihilation?  I thought quasars produce large quantities of gamma rays?

I don't like that idea. The electromagnetic force is far more powerful than gravity. Positively charged particles are affected by electromagnetic fields in a different fashion to negatively charged particles, irrespective of whether they're matter or antimatter. And matter and antimatter are affected by gravity the same way, and cause gravity the same way.

Yes, but I'm suggesting the electromagnetic field only as comparison, not that it is an electromagnetic field.  I'm wondering whether there is some other universal force that does differentiate between matter and antimatter, and that this universal field may be one factor of the gravitational constant?  If this were true, and considering photons are their own antiparticle, wouldn't that make photons massless particles?
 

Offline Farsight

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Re: Could there be both matter and antimatter galaxies?
« Reply #4 on: 15/02/2010 22:55:22 »
So we definitely see antimatter(or at least positrons) at the center of our galaxy?
Yes, see for example http://www.sciencedaily.com/releases/2009/07/090708201840.htm

I'm sure you are correct, but how do we know this? I was under the impression we have only observed extremely small quantities of antimatter, and only at extremely high speeds. It only makes sense that antimatter would be affected by gravitational pressure, and we have only observed it deep in our own gravity well. If we have only viewed small particles, and those particles don't have enough mass to create a noticeable curvature of space time, how do we know that say an antimatter star doesn't curve space opposite to our own? If it did, and photons map the curvature of space, wouldn't we be unable to see it?
Photons map the curvature of spacetime, not space. Throw a ball across the room, and it travels in an arc. Throw a ball faster and the arc is flatter. If it was curved space, the arc would be the same. Energy causes this, irrespective of its disposition. Whilst I can't show you any evidence (see http://en.wikipedia.org/wiki/Gravitational_interaction_of_antimatter) that's what relativity tells us, and I'm 100% confident it's correct.   

I thought gamma radiation was evidence of electron/positron annihilation?  I thought quasars produce large quantities of gamma rays?
They do, but gamma rays are evidence of electron/positron annihilation when they're 511keV. Gamma rays come with different energies/ freqencies too.

Yes, but I'm suggesting the electromagnetic field only as comparison, not that it is an electromagnetic field. I'm wondering whether there is some other universal force that does differentiate between matter and antimatter, and that this universal field may be one factor of the gravitational constant? If this were true, and considering photons are their own antiparticle, wouldn't that make photons massless particles?
There's some asymmetry in the weak interaction, see http://en.wikipedia.org/wiki/Weak_interaction#Violation_of_symmetry, but it isn't what you're looking for. Yes, photons are massless.
 

Offline norcalclimber

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Could there be both matter and antimatter galaxies?
« Reply #5 on: 18/02/2010 18:23:45 »
It has been pointed out to me that my subject line of my posts need to be phrased as a question, I have edited this post to reflect that.
 

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Could there be both matter and antimatter galaxies?
« Reply #5 on: 18/02/2010 18:23:45 »

 

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