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    Why There Is More Matter Than Antimatter
    By Sascha Vongehr | April 9th 2012 04:40 AM | 4 comments | Print | E-mail | Track Comments
    About Sascha

    Dr. Sascha Vongehr [风洒沙] studied phil/math/chem/phys in Germany, obtained a BSc in theoretical physics (electro-mag) & MSc (stringtheory)...

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    Matter annihilates antimatter, mostly resulting in light (no, not “pure energy”, whatever that is supposed to be). Matter and antimatter can also come into existence together via a process that is the reverse of annihilation. Yet our universe has almost no antimatter. How can such be if they come into existence in exactly equal amounts, each particle together with its antiparticle?



    Science writers at times promise to reveal how the oh-so-mysterious matter surplus originated, every time pushing back the question one more iteration without coming clean. Recently, Ethan Siegel did it yet again, and that recent piece is especially annoying because he even promises an answer to the now all fashionable why is there anything (WISA) question*. That there is more matter than antimatter is of course not an answer to why is there something instead of nothing, except if you think that the energy that the particles originate from and annihilate each other into is “nothing”. Such is yet worse than Lawrence M. Krauss, who thinks that a quantum field in a particular state is “nothing”, which David Albert has sufficiently criticized, so I do not need to do it here.


    There is interesting physics in Ethan’s piece, like always, and it is all relevant to matter creation: CP violation, that the imbalance is generated far from thermodynamic equilibrium, and that the standard model’s conservation laws do allow the imbalance to come about as long as the lepton number subtracted from the baryon number (B-L) is conserved. However, when it comes to “explaining” the matter surplus, the given “reason” is:


    He assumes some particle Q+ that in 60 percent of all cases decays into a proton and a neutrino, and in 40% of cases into an antineutron and positron. If you can think for yourself, you know that he is finished already. He has 6 particles for every 4 antiparticles by assuming some new god particle.


    Although the Q+ thingy already blows the particle/antiparticle symmetry to pieces (a “particle” that decays into two antiparticles?!?), an also assumed “antiparticle” Q- decays four times out of ten into an antiproton and antineutrino and six times into a neutron and an electron. You read this correctly: Not 6-4 as the hyped meaning of “anti” strongly suggests, but 4-6!



    Now he goes on to add mutual annihilation of the decay products and then belatedly discovers that, surprise surprise, more matter than antimatter is left over! Of course he was finished long before. He simply assumed that only four out of ten are antimatter, period.


    Now to be clear, the assumed decay reaction is less based on theory than simply ad hoc and he has previously done the same with a Y and an antiY. The Y decays into a proton and electron or antineutron and antineutrino and the antiY decays correspondingly into antiproton and positron or neutron and neutrino.


    Just as an aside: The well known neutron decay into p+ + W- has the virtual W- decaying into an electron and antineutrino, so it holds “Y + antineutrino = n”. Let’s add a neutrino to both sides and we get Y = n + neutrino. But Y also supposedly can decay into antineutron and antineutrino. So Y is somewhat equivalent to its own antiparticle anyway. Just like Q does, it right from the start blew the X/anti-X complementarity to pieces, but this very fact is not mentioned; in fact, it stays hidden.


    As usual, the offered “explanation” for there being more particles than antiparticles is simply that there are more particles than antiparticles. Yes, thanks, but we knew that! Sorry, not what we wanted to know! We came because of the word “antimatter” and the mystery that has been created around it, which is why we find an imbalance between them upsetting. Good ex-Christians need the good to balance the evil antigood.


    Why not be upfront with that matter and antimatter are not as complementary as introduced, yes, why introduce them so misleadingly?


    The general structure of popular science writing is: Take something mysterious, best something widely misrepresented like the big bang, enhance the confusion and mystery in order to further drive up interest, then present sophisticated non-explanations exclaiming awesome science did it yet again and god is thus dead. Ignore all criticism because you are already busy distorting the next topic, and just sell the same nonsense slightly altered every few months. This is the opposite of enlightenment.

    It is by now obvious that the convenient matter/antimatter terminology and especially the idiotic science writing around it are what created and today conserve the mystery in the first place. Antimatter is introduced as if it is the exact opposite of matter, as if some fundamental Ying peels off from Yang leaving it therefore in exact proportion, splitting nothingness. Look how Ethan starts his post:


    “"Think binary. When matter meets antimatter, both vanish, into pure energy. But both existed; I mean, there was a condition we'll call 'existence.' Think of one and minus one. Together they add up to zero, nothing, nada, niente, right? Picture them together, then picture them separating--peeling apart. ... Now you have something, you have two somethings, where once you had nothing." -John Updike


    Why not tell the readers clearly that this is obviously just a misleading misunderstanding? Might cost some site hits, but such could perhaps be counted as enlightenment, which science was supposedly about.


    “Antimatter” is a word, a traditional terminology that sticks well because it describes the fact that as far as we can observe in experiments, all particles with rest-mass have an antiparticle with which they can "annihilate", leaving radiation. However, the dominance of matter over antimatter already shows that they cannot have resulted from a balanced zero-sum process, at least not relative to our observable universe.


    We live in a region where there happens to be a surplus, perhaps Ethan’s 6 to 4, but this is balanced by other regions where there holds 4 to 6 instead. This has indeed to do with handedness (chirality), i.e. the mentioned CP violation of the weak force. Thus, the “other regions” are likely other universes in the multiverse. In some sense, space in our observable universe is a carpet woven from left-spun yarn. Relative to this handedness, the X/antiX distinction is simply not as symmetric as hyped, just as the left-handed versus right-handed symmetry is broken.


    ------------------------

    * Ethan shrugged off criticism claiming the clear WISA connection in the title was a “colloquialism” that I do not get because my English is terrible. Yet it is not just the title I complained about - the whole post claims to be about WISA! Lawrence Krauss perhaps made the same “colloquialism” throughout his book and did not mean to support atheism. Hell, even Richard Dawkins with his terrible English may have misunderstood Krauss. Sorry, but no, arrogant shoving to the side is not how I like to see constructive criticism being disposed of. Science outreach should not nourish naïve scientism and should not alienate religious and those who understand philosophical questions. Somebody’s articles increasingly leave the impression that arrogant scientists plainly do not understand deeper issues and/or science writers simply work a niche market and do not care.

    Comments

    It might be something you've already seen Sascha, but Prof Matt Strassler does a pretty nice job today explaining the same topic you once attempted to educate poor Lubos about -- the difference between mass and energy.

    "But for the moment, suffice it to say that energy is not itself an object. An atom is an object; energy is not. Energy is something which objects can have, and groups of objects can have — a property of objects that characterizes their behavior and their relationships to one another... Let’s first examine the notion that 'matter and anti-matter annihilate to pure energy.' This, simply put, isn’t true, for several reasons."
    http://profmattstrassler.com/articles-and-posts/particle-physics-basics/...
    Cheers!

    vongehr
    Thanks for the hint. Matt is more careful than many others, but I do not follow the blog and have not linked any specific posts simply because he portrays fields as having ontological primacy and perhaps being directly real. Such is not conductive to further fundamental insights. I take such descriptions at times as an assumed basis of a discourse, sometimes qualifying them as the best of our time. He seems to "truly believe" which is an impression that I avoid in order not to alienate those critical of naive scientism etc.
    UvaE
    He may give fields a central priority--not that i understand the intricacies of the debate---- but he does at times share your writing tone:

    The term “pure energy” is a mix of poetry, shorthand and garbage.   Since photons have no mass, they have no mass-energy, and that means their energy is “purely motion-energy”.  But that does not mean the same thing, either in physics or intuitively to the non-expert, as saying photons are “pure energy”.

    What is meant by “pure energy”?  This is almost always used in reference to photons,.....But it’s a terrible thing to do.  Energy is something that photons have; it is not what photons are.  [I have height and weight; that does not mean I am height and weight.] 
    vongehr
    That is what I mean by him being unusually careful. My problem is that he isn't as careful with fields. Fields are defined on some sort of space, i.e. a field is something that gives a value, say a vector or a probability, to members (say points) in/on that space.