Anti-matter Questionaire

[ParanoiA]

I was wondering...if matter makes up the universe, planets, life and so forth, then is it believed that anti-matter would exist as a mirror image of this? Or could anti-matter really exist in any form? Do we know?

 

Could anti-matter all exist in one condensed point in the universe as one massive planet or a ridiculously cluttered solar system?

 

Does it follow that the laws of physics, as they apply to matter, would have to apply to anti-matter?

[YT2095]

I`m sure that if there were such a condensed conglomerate of this, it would be more than easily observable anywhere in the universe by the amount annihilation radiation given off.

 

also a "universe" composed entirely of anti-mater would have no real reason to behave any differently to this one, particle for particle just reverse charges

 

that would be My speculation.

[Reaper]

We created an anti-matter hydrogen atom before, back in 1995

 

We have yet to determine whether or not antimatter atoms have any fundamentally different properties.

 

I agree with YT, if there was a large amount of it it would be detectable, especially in the early universe. Anti-matter annihilation gives off gamma radiation. Current theories suggest that there was slightly more matter than antimatter in the very early universe, and that is why most of the universe is matter but not antimatter. As to why this is is another issue all together.

[ParanoiA]

We created an anti-matter hydrogen atom before.

 

We have yet to determine whether or not antimatter atoms have any fundamentally different properties.

 

I agree with YT, if there was a large amount of it it would be detectable, especially in the early universe. Anti-matter annihilation gives off gamma radiation. Current theories suggest that there was slightly more matter than antimatter in the very early universe, and that is why there is matter but not antimatter.

 

Interesting. Are you saying that we now believe there is no antimatter in the universe, or very little? So, then, could it be possible that antimatter could exist at a relatively condensed point in the universe, but not be all that detectable due to the low quantity in existence?

 

I thought scientists were still looking for antimatter and were basically scratching their heads as to where all of the antimatter went.

 

I'm also confused because I thought matter could not be created nor destroyed, just changed. So I figured antimatter would be the same way.

[CPL.Luke]

matter can be destroyed it just turns into energy of some form or another.

 

scientists are still lookin for the antimatter but haven't come close to finding it yet, and it is now believed that for whatever reason, there just isn't any anti matter in the universe.

[YT2095]

I`ve heard it proposed that the Background radiation (even the white noise static on a TV screen) are the remnants of this radiation.

 

I have no idea of how true this is or not, but it may be worth a mention

[Severian]

The actual measurement (from WMAP) is:

 

[math] \frac{n_B - n_{\bar B}}{n_\gamma} = (6.1 \pm 0.3) \times 10^{-10}[/math]

 

where [math]n_B, \, n_{\bar B}[/math] and [math]n_\gamma[/math] are the number of baryons, anti-baryons and photons respectively. The number of photons is just used for normalization - the important thing to notice is that the number of baryons minus anti-baryons is different from zero (more than can be explained from the small error).

 

BTW, baryons are things like protons and neutrons.

[ParanoiA]

So, if the number of baryons minus anti-baryons is different from zero, you must be saying that there is no parity in terms of quantity between matter and antimatter right?

 

Or is this a more local application? I guess I'm not sure what that equation represents, in terms of dynamics. (well in any terms really, but...)

[Severian]

This is very global. The various n's represent the total number of the particle in the universe. So there are a lot more baryons than antibaryons.

 

(I am not sure why they present it like this. Wouldn't [math]\frac{n_B-n_{\bar B}}{n_B+n_{\bar B}}[/math] be more interesting?)

 

We still don't understand why this is the case. If the universe were created in the Big Bang and CP was conserved then we would expect this quantity to be zero (ie. the same number of anti-baryons as baryons). Since CP is violated in the Standard Model (ie. baryons behave differently from antibaryons), there was some hope that this difference could be naturally explained, but on doing the calculation, there is not nearly enough CP violation in the Standard Model to explain it.

[Fuzzwood]

I`m sure that if there were such a condensed conglomerate of this, it would be more than easily observable anywhere in the universe by the amount annihilation radiation given off.

 

also a "universe" composed entirely of anti-mater would have no real reason to behave any differently to this one, particle for particle just reverse charges

 

that would be My speculation.

 

I think you can say we live in a universe of antimatter, and the stuff we create is matter. It's only terminology.

[YT2095]

it`s not terminology it`s semantics more than anything else as such a thing would be entirely Relative, an Anti-matter universe (to us) would not be to those that reside in it, We would be.

 

Anti just means opposite, it doesn`t imply right or wrong.

[Fuzzwood]

it`s not terminology it`s semantics more than anything else as such a thing would be entirely Relative, an Anti-matter universe (to us) would not be to those that reside in it, We would be.

 

Anti just means opposite, it doesn`t imply right or wrong.

 

That is what i was trying to say

[nexteinstein]

I agree with paranoia cause anti matter does behave like matter but the thing is that when matter and antimmatter meet they annihalate each other to pure energy but matter and energy are interchangeble.

[Severian]

Observationally, I don't think there would be any problem with having a big ball of pure antimatter out there in the universe. It would have to be either dark (ie. uncharged particle not radiating light) or small enough that we just haven't noticed it.

 

It wouldn't just annihilate because the space is such a good vacuum - there is nothing to annihilate with.

 

In fact, quite a good question might be, how do we know that (some of) the stars we see are not made of antimatter? I am not sure I know the answer to that.

 

(Of course, from a theoretical point of view it doesn't really work without having a mechanism to separate the matter and antimatter into solar systems.)

[swansont]

Observationally, I don't think there would be any problem with having a big ball of pure antimatter out there in the universe. It would have to be either dark (ie. uncharged particle not radiating light) or small enough that we just haven't noticed it.

 

It wouldn't just annihilate because the space is such a good vacuum - there is nothing to annihilate with.

 

In fact, quite a good question might be, how do we know that (some of) the stars we see are not made of antimatter? I am not sure I know the answer to that.

 

(Of course, from a theoretical point of view it doesn't really work without having a mechanism to separate the matter and antimatter into solar systems.)

 

And I think the last point is key. There may be great separation now, but that wouldn't have been the case in the past. There would be residual annihilation radiation from the boundary before separation occurred, and there would be nothing to separate the matter from the antimatter.

[ParanoiA]

I agree with paranoia cause anti matter does behave like matter but the thing is that when matter and antimmatter meet they annihalate each other to pure energy but matter and energy are interchangeble.

 

So what is the difference between energy created from matter and energy created from anti-matter? And am I phrasing that right?

 

Observationally' date=' I don't think there would be any problem with having a big ball of pure antimatter out there in the universe. It would have to be either dark (ie. uncharged particle not radiating light) or small enough that we just haven't noticed it.

 

It wouldn't just annihilate because the space is such a good vacuum - there is nothing to annihilate with.[/quote']

 

So, is the contact of matter and anti-matter the only method of annihilation? And do we know what happens to this matter when this happens?

 

In fact' date=' quite a good question might be, how do we know that (some of) the stars we see are not made of antimatter? I am not sure I know the answer to that.

 

(Of course, from a theoretical point of view it doesn't really work without having a mechanism to separate the matter and antimatter into solar systems.)[/quote']

 

Could that have been the result of the big bang? The scattering of matter or anti-matter or both? It should be obvious I'm way over my head here...

 

And I think the last point is key. There may be great separation now, but that wouldn't have been the case in the past. There would be residual annihilation radiation from the boundary before separation occurred, and there would be nothing to separate the matter from the antimatter.

 

If I'm following you, and I'm not sure that I am, then what boundary are you referring to here? If there was no separation of matter and anti-matter in the past, and they annihilated each other over time by mere proximity consequence then what boundary is present?

[swansont]

If I'm following you, and I'm not sure that I am, then what boundary are you referring to here? If there was no separation of matter and anti-matter in the past, and they annihilated each other over time by mere proximity consequence then what boundary is present?

 

If they annihilated in the past, there should be some residual radiation from that.

 

If that happened, why did it stop? Why would matter and antimatter move away from each other to create the necessary separation (which was Severian's parenthetical remark) to make the annihilation cease? Without such a mechanism, there should have been a region where matter and antimatter continued to meet and annihilate.

[ParanoiA]

If they annihilated in the past, there should be some residual radiation from that.

 

If that happened, why did it stop? Why would matter and antimatter move away from each other to create the necessary separation (which was Severian's parenthetical remark) to make the annihilation cease? Without such a mechanism, there should have been a region where matter and antimatter continued to meet and annihilate.

 

Hmmm..so is it not possible that it was inevitable? If I scatter matter and anti-matter in a room, randomly, I would expect concentrations of one or the other, even just slightly - just by mere chance. So, isn't it possible that only non-concentrated matter and anti-matter would annihilate each other and that only the clumps would be left - more than likely at a distance that would negate any eventual contact?

 

So, if matter and anti-matter are scattered about, wouldn't they naturally form a division, separation, between them due to the inevitable variable of concentration? And then could the continual expansion of the universe keep them separated, pulling them further and further apart?

 

Perhaps the matter we've validated (as not being anti-matter) is such a clump, that was intermixed with anti-matter at one time but by sheer numbers and concentration has annihilated anti-matter out of this region? Which leads into the OP asking about possibility of anti-matter existing in some other part of the universe.

 

I think I need to put away the scifi for a bit...

[swansont]

Hmmm..so is it not possible that it was inevitable? If I scatter matter and anti-matter in a room, randomly, I would expect concentrations of one or the other, even just slightly - just by mere chance. So, isn't it possible that only non-concentrated matter and anti-matter would annihilate each other and that only the clumps would be left - more than likely at a distance that would negate any eventual contact?

 

So, if matter and anti-matter are scattered about, wouldn't they naturally form a division, separation, between them due to the inevitable variable of concentration? And then could the continual expansion of the universe keep them separated, pulling them further and further apart?

 

Perhaps the matter we've validated (as not being anti-matter) is such a clump, that was intermixed with anti-matter at one time but by sheer numbers and concentration has annihilated anti-matter out of this region? Which leads into the OP asking about possibility of anti-matter existing in some other part of the universe.

 

I think I need to put away the scifi for a bit...

 

 

I suppose, but where is the radiation from the annihilations that must have occurred before everything was separated? What we see is a thermal distribution.

[Severian]

This is especially true because the electron is so light that it falls out of equilibrium rather late on. Before then, any particle anti-particle annihilation rate is compensated by the back reaction of [math]\gamma \to e^+e^-[/math].

 

I suppose if all your particle were very heavy (so that they annihilate early) then you might be able to argue this.

[Neutrino-pop]

Is the name "anti-matter "true to the nature of what it describes? What exactly is anti-matter supposed to be? When I hear the term I think of a negative comparisson or a mirrored image of something.

 

But I question how do you then describe an existence of what something is not being? If there were such an existence of non-existence could we use that to explain things like repulsion and inflation? Is it possible that there are light years worth of nothingness units in between the cells in my body and I'm not aware of it because it's nothing and has no properties? What if various lacks of properties result in effects such as darkg energy.

Is this a retar-ted idea?

[pioneer]

Anti-matter is a misnomer that leads to confusion. The only thing that is anti is charge. The matter part is essentially the same for both. If you look at the electron and positron, they have the same mass but only difffer by charge. Since the anti only technically reflects two charges, then electrons and protons are matter and anti-matter from different families.

 

In the traditional sense of the term matter and anti-matter, in light of where did all the anti-matter go, does that mean the beginning of the universe had 1000 or 1,000,000 times more mass/energy to account for anhillation? In other words, what we see should only be the tiny fraction that remained. There should be primal anhillation energy floating around. If the cosmic background microwaves is the primal energy, is that all we got out of all that matter-antimatter anhilliation. Skimpy yield. Based on that traditional anti-matter should have been less than 1%.

 

It makes far more sense, since there is only positive matter and no negative matter, than matter-antimatter simply swapped charges until the most stable states appeared, which is the anti cousins in hydrogen. This high efficiency would give off much less energy, which is observed.

 

In other words, there is something inherent in the proton and electron that makes these far more stable then anti-proton and the positron. The positive charge appeared to have found more stablity with extra mass. While negative charge found much more stability with slight mass.

[Severian]

It is more than just charge. All the quantum numbers are reversed. For example, the electron has opposite isospin from the positron, and opposite lepton number too.

 

The idea of antiparticles is really coming out of the Feynman Stuechleberg interpretation, where antiparticles traveling forward in time are recognised to be particles traveling backwards in time.

[antimatter]

I have actually heard that there are portions of the Universe that consist of just antimatter.

[Klaynos]

I have actually heard that there are portions of the Universe that consist of just antimatter.

 

There would be massive amounts of annihilation at the boundary, they would literally glow!