Thread: Where has all the anti-matter gone?

I have been thinking about what happened to the anti-matter component of the universe and why it cannot have been destroyed at the formation point of the universe. We understand from the current models that a significant mass component of the universe is unaccounted for, and may be down to the missing anti-matter. We know this missing mass exists as it has an observable influence of universal masses.

My thoughts on this:-
At the start point of the universe there was an equal amount of matter and anti-matter created in the big bang.
If we accept that anti-matter and matter are true opposites [attracting each other equally] it is reasonable to expect that the anti-matter traveled out from the big bang as an expanding wave in front of the matter component, and as the anti-matter stays in front of the expanding matter they are stable to each other and do not interact except gravitationally.
It is possible that the expanding wave of anti-matter is pulling the matter universe outwards from the origin point.
Hence we can exist in an expanding universe where anti-matter and matter co-exist but only interact gravitationally on each other.

This is an interesting, but very unlikely idea. It is not that matter and antimatter were created separately. The main formation process is the pair formation out of high energy photons, i.e. a matter particle and an antimatter particle appear at the same place with some excess kinetic energy that depends on the difference between the rest mass energy equivalence of the two particles and the photon energy. Please also keep in mind that not all particles are electrically charged, e.g. neutron and antineutron.

In addition, the heat of the (anti)particle ensembles is a measure of the mean kinetic energy of those particles. Therefore, the high temperatures caused a lot of chaotic movement, whose direction is not influenced by the direction of the expansion. Only the temperature, i.e. the kinetic energy changes.

I just do not see how both ensembles of matter and antimatter could have been separated.

Furthermore, there is already a model that could describe the uneven distribution of matter and antimatter. See also the discussion at:
http://www.thescienceforum.com/Does-...ter-30962t.php

I understand; however I wonder if the chaos in the high kinetic energy environment events post the zero-point would have separated the matter and anti-matter in the first major kinetic expansion of the universe. The excess kinetic energy delta in the anti-matter ensured it expanded faster than the matter left behind and drawn out to follow the anti-matter wave front.
Current thinking is both matter and anti-matter were created at the zero-point.
The alternative without the expansion and separation above would be that they cancelled each other immediately after the zero-point?
If AMS-02 detects a universal expanding anti-matter wave-front then I might be right.

Further to this, the environment in the early phase [+3 minutes] of BBN would have been light hydrogen isotopes H-1; so 7 protons for every neutron. This is a far simpler environment than the post BBN phase. If the anti-matter opposites occurred at the same point [+3 minutes] and expanded out as a wave [as previous thoughts] they would be separated from the post-BBN developments of beryllium and more complex forms. One would assume the anti-matter equivalents would develop within the expanding anti-matter wave as the universe got to +20 minutes and fusion started occurring; however there would be no interactions between matter and anti-matter apart from gravitational forces.

Further to this thought train; if the early environment phase of BBN was very strongly magnetised or solid-charged is it reasonable to consider that the protons and anti-protons could be driven apart by coulomb repulsion?

Originally Posted by Graham271

Further to this thought train; if the early environment phase of BBN was very strongly magnetised or solid-charged is it reasonable to consider that the protons and anti-protons could be driven apart by coulomb repulsion?

If anything, they should attract each other by Coulomb forces. Maybe, you are thinking of the Lorentz force of charged particles in a magnetic field? One given proton and one given antiproton may be deflected into different directions, but they may also end up spiralling away into the same direction of the magnetic field lines, just with the opposite sense of rotation. You also have to consider that there are protons and antiprotons everywhere and running in every direction. So, eventually one of each would meet and annihilate.

CP-symmetry cannot apply in the early BBN phase otherwise [with the assumption of equal amounts of matter and anti-matter] they would have cancelled each other out and left a universe of radiation and no matter. Since this is not the case we assume a CP violation in this early BBN phase. If momenta were reversed as is considered in a CP violation; is it not reasonable to consider an early BBN phase repulsion by Coulomb forces in a highly magnetised environment. Then a formation of CP symmetry developed in a matter environment; after the event of matter / anti-matter separation.

The potential effect of anti-matter behaving differently in reference to gravitational effects to matter is also a consideration here. One wonders if we exist inside an anti-matter bubble. I go back to my initial thought:

It is possible that the expanding wave front of anti-matter is pulling the matter universe outwards from the big-bang origin point.
Hence we can exist in an expanding universe where anti-matter and matter co-exist but only interact gravitationally on each other.

If an anti-particle makes contact with an normal one, they annihilate each other.

but do we know for a fact that an entire anti-matter atom will negate itself if in contact with a normal atom of the same kind?


Oh, and, can anyone speculate as to what an anti-matter star might look like? How would one detect that a distant star is made with anti-particles?

In physics, the word is used to denote the process that occurs when a subatomic particle collides with its respective antiparticle.[2] Since energy and momentum must be conserved, the particles are simply transformed into new particles. They do not disappear from existence. Antiparticles have exactly opposite additive quantum numbers from particles, so the sums of all quantum numbers of the original pair are zero. Hence, any set of particles may be produced whose total quantum numbers are also zero as long as conservation of energy and conservation of momentum are obeyed. When a particle and its antiparticle collide, their energy is converted into a force carrier particle, such as a gluon, W/Z force carrier particle, or a photon. These particles are afterwards transformed into other particles.[3]

Annihilation - Wikipedia, the free encyclopedia

It is possible that the expanding wave front of anti-matter is pulling the matter universe outwards from the big-bang origin point.

Well, to begin with, there is no 'origin point'. Nor is there a expanding wave front. You are picturing the BB expansion as a type of explosion, originating somewhere in space and having a center.

The BB was/is not a release of energy projecting matter through space. The BB is the expansion of every point in space away from every other point. Thus there is no 'center', the BB happens at every point throughout the universe.

Originally Posted by Graham271

The potential effect of anti-matter behaving differently in reference to gravitational effects to matter is also a consideration here.

There is no reason to expect that antimatter behaves any differently to ordinary matter.

One wonders if we exist inside an anti-matter bubble.

If we did, we would see characteristic radiation at the boundary between matter and anit-matter.

It is possible that the expanding wave front of anti-matter is pulling the matter universe outwards from the big-bang origin point.

Why would antimatter do this any more than matter does? And we know that matter does not do this - as Isaac newton proved several hundred years ago. You have some catching up to do.

Hence we can exist in an expanding universe where anti-matter and matter co-exist but only interact gravitationally on each other.

In which case, they would be gravitationally attracted, annihilate and generate radiation we could detect.

Where has all the anti-matter gone, long time passing.
Where has all the anti-matter gone, long time ago...
Where has all the anti-matter gone, gone for parallel verses every one.....

[1205.4033] On the local dark matter densityThe latest paper(s) on dark matter seem to boil down to using a common galactic center of rotation vs using an axis of rotation.

Even then there are problems.

Galactic Rotation Curves and the Dark Matter Myth

Originally Posted by Laurieag

Galactic Rotation Curves and the Dark Matter Myth

That does not appear to be a reliable source for scientific information. Long on assertions and opinions, short on evidence, math and accuracy.

Mordehai Milgrom has a new paper out "Testing MOND with galaxy-galaxy gravitational lensing" without dark matter.

http://arxiv.org/abs/1305.3516v1

http://en.wikipedia.org/wiki/Mordehai_Milgrom

Originally Posted by Strange

Originally Posted by Laurieag

Galactic Rotation Curves and the Dark Matter Myth

That does not appear to be a reliable source for scientific information. Long on assertions and opinions, short on evidence, math and accuracy.

And that's putting it mildly. That site is out-and-out cranky. They deny the correctness of the blackbody radiation formula; they ignore the quantitative explanations of the Pioneer "anomaly"; etc. It seems to have been constructed by a bored undergraduate.

Oh, and relativity is wrong, too, so I learned from that site. Einstein was an idiot.

Standard crackpot catechism.

Originally Posted by tk421

Standard crackpot catechism.

Standard straw man.

Originally Posted by Laurieag

Originally Posted by tk421

Standard crackpot catechism.

Standard straw man.

That's your reply? Weak. Very weak. Your taste in references is sketchy at best. That website is total crap.

The link to Moti's paper? Much better. MOND is certainly a credible, legitimate alternative. But that other site is, total and utter (udder?) bull feces.

If a website is dismissive about science, it shows they don't know much about the science. You can know science very very well and still disagree with its conclusions, but it's utterly impossible to know it very very well and simply dismiss it.

Originally Posted by kojax

If a website is dismissive about science, it shows they don't know much about the science. You can know science very very well and still disagree with its conclusions, but it's utterly impossible to know it very very well and simply dismiss it.

Exactly. That website's creator, "Thomas Smid," is an infamous crank. It took me a bit to realize whose site that was. He polluted various forums a few years back, mainly with his anti-relativity rants. It was clear from those that he has no clue what he's talking about. His entire site really should be relabeled "stuff that I couldn't understood in school, and therefore declare to be wrong." He rails against quantum theory, relativity (both GR and SR), thermo, Maxwell... you name it, he hates it. Typical arrogant fool.

Has anyone ever found any natural occuring anti matter? Have we yet ever constructed a complete antimatter atom?

Originally Posted by Sealeaf

Has anyone ever found any natural occuring anti matter? Have we yet ever constructed a complete antimatter atom?

Detections of antimatter occur routinely, if indirectly. There is a characteristic energy produced when, say, a positron and electron meet and mutually annihilate (in this specific example, you get a 511keV gamma ray).

And a bit over a decade or so ago, a minute quantity of antihydrogen was produced at CERN.

Anti-helium has also been produced.

The CERN Alpha project is working on producing anti-hydrogen to measure its proeprties. Including, eventually, making enough to determine how it behaves gravitationally.

Home | ALPHA Experiment

aren't the photons in the cmbr the result from the matter anti-matter interaction of the early universe?