Talk:Baryon asymmetry

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antimatter travels back in time
Wow, talking about a huge big white elephant in cosmology. Apparently every single physicist has completely forgotten that antimatter is matter with the time direction in the negative. Dirac's solution inverts the time direction. That means that antimatter travels back in time. Of course there is no antimatter in a forward-timed-universe, unless specifically created by high energy phenomena (i.e., you have to put some effort in it). In fact, 99,9999% (the part after the comma isn't really relevant) of all physicists  seems to forget that we exist not in a three- or four-dimensional universe, but in a 3.5 dimensional universe, if conceding time is the highest dimension. We have free choice of movement (or interaction) in three dimensions, yet no choice in the fourth, unless by high-energy laboratory experiments. It is truly ridiculous to see college-educated people invoking string-theory (which actually implies that much of current state three-dimensional physics cannot be understood unless, mathematically, one dimension is added in abstracto to make more sense) without actually realizing the true state of particles, and then adding up to 20+ dimensions mathematically because they can't make heads or tails of it. Pathetic, really. Crusty007 (talk) 00:03, 26 February 2009 (UTC)
 * hmm i dont quite see negative time there ... as that doesnt exist IMHO, but antimatter does exist. you even say it yourself, that time just goes forward ... 220.142.128.208 (talk) 19:05, 21 May 2009 (UTC)
 * I think the original writer is missing the point...the point is that whenever we create matter "by high-energy experiments" we always get an equal amount of antimatter. The big bang was the ultimate "high-energy experiment", with lots more energy, and hence lots more matter than any experiment we can produce. So why was there not an equal amount of antimatter produced then? The problem is that simple... [31 August 2009‎ Grant Gussie ]

Well if matter and antimatter were both being created and annihilating and there was even a slight preponderance of matter over time that got amplified. A Slight preponderance of matter that can't yet be demonstrated experimentally would be sufficient, I think. Proxima Centauri (talk) 11:37, 7 June 2011 (UTC)


 * Physicists don't appear to think that Dirac's solution makes antimatter travel back wards in time. Worldline diagrams showing matter-antimatter virtual particle pairs being born and annihilating shows them originating at the same location in space and time, both moving forward in time and slightly apart in space, and then moving together in space and annihilating each other. It's pretty clear in these diagrams that antimatter is not expected to travel backwards in time like somes sort of tachyons. And these virtual particle-antiparticle pair annihilations are the foundation of the Hawking radiation theory, which is widely accepted today. 2601:441:4480:53B0:94A8:F2C5:C527:7EDA (talk) 03:49, 14 November 2018 (UTC)

News story : Fermilab on neutral B-meson decay
It appears that the asymmetry may have been replicated at Fermilab: A New Clue to Explain Existence. The universe is getting more bizarre all the time.&mdash;RJH (talk) 16:12, 18 May 2010 (UTC)
 * They reported neutral B-mesons decaying 1% more into muons than anti-muons. and "The observed preponderance is about 50 times what is predicted by the Standard Model..." - but contradicted later by LHCb results - Rod57 (talk) 10:06, 10 September 2016 (UTC)

Intro is flat out wrong!
It is not true that matter would have been completely cancelled by anti matter, Since matter + anti matter <=> photon goes both ways. The baryon to photon ratio would just be about 9 orders of magnitude smaller than it is now. Though I recall the calculation was not completely trivial. — Preceding unsigned comment added by 82.72.121.51 (talk) 20:03, 30 October 2011 (UTC)

Solution to the Baryon asymmetry problem
According to relativity, the Space-time interval from one point in space time to another that's x, y, and z, light seconds away from it in perpendicular directions and t seconds into the future is √t2 - x2 - y2 - z2 seconds. Thus, the set of all points in space time that have a 1 second Space-time interval from the big bang is a uniform infinte 3 dimensional hyperbolic space and an observer near the edge of the universe does not observe themself as being at the edge of the universe but instead observes themself as being in the centre of a much younger universe. Since the set of all points in space-time that have a space time interval of 13 billion years from the big bang is an infinitely big uniform hyperbolic space, it has an equal amount of matter and anti-matter. Even so, localized regions can be almost completely regular matter or almost completely anti-matter. The reason is that nothing is perfect and the slight drifting of matter and anti-matter causes some regions to have only barely more matter then antimatter and vice versa but later on, in such a region, almost all of that matter and antimatter annihilates each other to have which ever there was more of exist in a much smaller amount than before. Even unobservably large regions of the universe that initially had barely more matter than antimatter could have almost all of the matter and antimatter in that region annihilate each other until there's only matter left at a much smaller quantity. There could easily be another point in space time that to us is much further into the future really close to the edge of the universe but in the frame of reference of that point is in the centre of the universe only 13 billion years after the big bang and that point might be surrounded by the same amount of antimatter up to an unonservably large distance with practically no matter at all. Most of the annihilation occured in the very early universe so the photons from the annihilation got really heavily redshifted into the microwave background radiation by the expansion of the universe. Blackbombchu (talk) 02:44, 11 December 2013 (UTC)


 * Are there any reliable sources for this? Paradoctor (talk) 05:21, 11 December 2013 (UTC)
 * According to the article Antimatter, that problem was considered one of the greatest unsolved problems in physics. I assumed the task of that problem was to give a very reasonable explanation that stops people from feeling like there's a contradiction from there being almost completely matter in the observable universe, not to prove the theory correct. Blackbombchu (talk) 19:08, 11 December 2013 (UTC)
 * In fact, there's no reason at all to assume that clusters of galaxies that are so far away from us that their rate of moving away from us exceeds their gravitational attraction are composed of matter and not antimatter. A photon is it's own antipartcle so we can't tell by looking whether it's matter or antimatter, Furthermore, it's moving away from us so fast that it never would have gotton a chance to annihilate a cluster of galaxies made of regular matter since the very early universe when almost all of the matter and antimatter in that region of space annihilated each othe leaving behind only antimatter. Bacuse it's moving away so fast that it would never get a chance to annihilate regular matter, we don't know that's it's made of regular matter and not anti-matter. Blackbombchu (talk) 19:47, 11 December 2013 (UTC)


 * Please take note of WP:NOTFORUM. If you have a suggestion for a change to the article, please specify what it should be, and support it with reliable sources. Discussion of any ideas you (or I) might have for explaining the baryon asymmetry do not belong here. Paradoctor (talk) 21:17, 11 December 2013 (UTC)
 * I know that this may be a little late, but it will serve as both further research and to show that you are misinterpreting Wikipedia guidelines. While Wikipedia is not a forum, that goes to the main article, this space (WP:TALK) is dedicated to that kind of discussion, secondly you should have suggested him to publish it into other venues, then use it as a source. Lastly, there are cases which reliable sources are not necessary, including when a subject is thoroughly discussed on its talk page and several members agree that it should be presented that way. Regards. Eduemoni↑talk↓  05:38, 4 February 2020 (UTC)
 * Probably just a statistical problems. If you toss 10 fair coins. There is less than 1/10 of a chance that 5 of them would land on head and 5 on tail. There were more than trillion of baryons created. — Preceding unsigned comment added by 58.8.152.221 (talk) 13:57, 17 September 2017 (UTC)

CP Violation section seems wrong
It seems to be saying there's no experimental evidence for CP-violation. That's not right. It's well established that the weak nuclear force violates CP-symmetry. The 1980 Nobel Prize in Physics was given for this discovery. Maybe it's correct to say that the known sources of CP-violation aren't enough to account for the Baryon asymmetry? Or that there's no evidence for CP-violation except in the weak force? - Tim314 (talk) 12:34, 13 May 2014 (UTC)
 * Currently the CP violation section says that it has been detected and measured, but surprisingly does not discuss how this does or might explain some or all of the baryon asymmetry. - Rod57 (talk) 09:44, 10 September 2016 (UTC)

Where does the "therefore" come from?
After calculating the CBR photon density, the next sentence is "Therefore, the asymmetry parameter η, as defined above, is not the "good" parameter" - Where does this conclusion come from? There is nothing to indicate what led to it 192.31.106.35 (talk) 18:07, 26 November 2019 (UTC)


 * I wholeheartedly agree, so I looked it up. I found this (arXiv:1801.10059 [astro-ph.CO]), and looking at pages 4-5 it is explained why the regular η parameter wouldn't be so "good" - heavier unstable particles (I guess they mean particles like mesons and baryons heavier than protons) would decay, releasing photons in the process. Those would be measured today as part of the CBR, and we would get a smaller η. The article states that the entropy S stays constant as the universe expands adiabatically in a conmoving volume, so s can be used instead of nγ. I am not sure if the numerical analysis of the CBR is actually necessary here, perhaps it's worthwhile to consider a revision of this part to make it more clear Kabum555 (talk) 15:05, 20 April 2020 (UTC)


 * My impression after reading the section three times: η is not a "good" parameter because nγ is not constant. Maybe some re-ordering of the preceding text would make this clearer. --Schlosser67 (talk) 08:37, 19 April 2024 (UTC)

Baryon Asymmetry Parameter
Can someone please put in the current estimate(s) of or limit(s) on the baryon asymmetry parameter(s)? With references please. The article only gives the values of nγ and s. Also it appears to be a carbon-copy of what's in Baryogenesis, these articles should be merged. --Jasondet (talk) 05:58, 26 March 2020 (UTC)

Matter-antimatter boundary density
The article states: "Regions of the universe where antimatter dominates... The density of matter in intergalactic space is reasonably well established at about one atom per cubic meter. Assuming this is a typical density near a boundary..."

I don't see that as a reasonable assumption, because surely matter-antimatter anihalation would reduce the density, would it not? MathewMunro (talk) 01:56, 19 April 2020 (UTC)


 * Also bear in mind that "the gravitational interaction of antimatter with matter [...] has not been conclusively observed by physicists" (see references of ). Thus, "assuming this is a typical density near a boundary..." could be incorrect: it could in fact be substantially lower, due to gravitational repulsion, and thus not produce detectable gamma ray luminosity. Perhaps there is no actual baryon asymmetry.  PensiveCoder (talk) 06:56, 29 July 2020 (UTC)
 * Maybe the energy or electrons can travel pass the Through the neutrino maybe this is the only thing providing mass is the electron because neutrino oscillations prove that everything basically is the electron 2600:1014:B1EA:E52C:E8F1:7518:A3C1:E49A (talk) 02:22, 17 October 2023 (UTC)