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LHCb Experiment Observes New Matter-Antimatter Difference
An anonymous reader writes "Matter and antimatter are thought to have existed in equal amounts at the beginning of the Universe, but today the Universe appears to be composed essentially of matter. By studying subtle differences in the behavior of particles and antiparticles, experiments at the LHC are seeking to cast light on this dominance of matter over antimatter. Now the LHCb experiment has observed a preference for matter over antimatter known as CP-violation in the decay of neutral B0s particles. The results are based on the analysis of data collected by the experiment in 2011."
Now the LHCb experiment has observed a preference for matter over antimatter known as CP-violation
If the pro-matter people are violating CP laws, I want nothing to do with them.
Just Say No to matter!
Q: Why is starting a comment in the Subject: line incredibly irritating?
Shutting down free speech with violence isn't fighting fascism. It IS fascism!
"CP-violation"
Right. Like I'm going to click on that link.
but the headline is a bit grandiose - there is nothing new about CP violation. CP violation has been known for a very long time and there are at least three other examples of it prior to LHCb report. Also, as CERN notes, others were not able to accumulate sufficient statistics to make the observational claim. Perhaps "CERN's LHCb confirms CP violation in another particle" my be both a more accurate way of describing it and also less "omg, ponies!"
What if monkeys can actually talk but refuse to do so because they don't want us to know?
What if quarks are actually microscopic doughnuts, and we can fly through them into an alternate universe where Snooki is president?
What if... ah, screw it, if you can't see where I'm going with this by now there's no hope for you.
systemd is Roko's Basilisk.
...that we are definitely made of matter. If we were made of anti-matter, wouldn't matter actually look like anti-matter to us, only because it isn't what we're made of?
Not really. We have defined an electron (matter) as the electron-particle that has a negative electric charge. A positron (anti-electron, antimatter) is an electron with a positive charge. Same goes for protons etc, and we know for certain that we and all the matter around us are composed of the 'matter' version.
Also, if matter and anti-matter existed in equal amounts at the beginning, wouldn't the remaining particles, regardless of what they are (after all the self-annihilation and whatnot) be considered matter by default?
No, because if they were equal in quantity, the left over particles would be a 50-50 mix of matter and antimatter, but this is not the case in reality.
You say "QED" like science is a closed method of understanding like logic is. The scientific method makes acknowledgement that its results are only accurate in as far as the controls we've been able impose in our experimentation and observation hold. We have never tested the laws of thermodynamics in conjunction with a singularity, and thus anything we say about their behavior there is an extrapolation. Extrapolation isn't induction, and what you just said isn't a proof.
What if space is matter and there's no such thing as a vacuum?/quote
NASA is going to be PISSED!!!
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Well, let me start by saying I don't know anything about this field. However, it seems to me that the interstellar medium is that kind of combination of really close to a vacuum and really big that still allows for quite a lot of particles out there hitting the edge of our solar system (I believe we're close to (or already are) getting actual measurements from probes we've sent out that have already left or will soon leave the solar system). Where these collisions occur, we'd expect matter-antimatter pairs to self-annihilate, and we could observe that. Since we don't, then the interstellar medium is made of matter. Likewise, if there were some antimatter stars out there, there would be a boundary between antimatter and matter in the interstellar medium and we could see the self-annihilations through observation. Maybe there are whole antimatter galaxies out there, but then again, we have discovered instances of galaxies that are colliding or have collided. Similar to stars passing through the interstellar medium, it seems we would be able to observe the matter-antimatter annihilation in at least some if they were in equal proportion.
If that were the case, then reactions that produce anti-matter would be detectable before they occur.
Meanwhile, in a parallel universe: "...experiments at the LHC are seeking to cast light on this dominance of antimatter over matter."
Without the universe there's no concept of causality and no concept of time. ...
The universe could still have come into existance all on its own.
Time is the dimension upon which we measure change. Without a dt, dv doesn't happen. Without time, how does the universe change from non-existing to existing?
James Dyson is going to be even more pissed. Freeman Dyson probably will be too. Why is the AC trying to piss off all sorts of Dysons?
Who is John Cabal?
James Dyson is going to be even more pissed. Freeman Dyson probably will be too. Why is the AC trying to piss off all sorts of Dysons?
He's probably hoping all the Dysons come to see him at the same time and angrily surround him.
He will then claim that he has the only Dyson sphere made out of real Dysons.
/sarcasm. Right, the universe just spontaneous came into existence.
From the Laws of Thermal Dynamics we know energy can not be created nor destroyed.
Einstein showed us all Matter is Energy.
Therefore the Universe has ALWAYS existed in one form or another.
Q.E.D.
Indeed, the curvature of the universe corresponds to negative energy, which can make the energy budget zero. See "A universe from nothing" by Lawrence Krauss (talk here) on why the energy budget can be zero.
One aspect in the big bang is that you can borrow energy from quantum mechanics if you give it back within a short time (the time needs to be shorter the more energy you borrow). Combine this with extremely fast inflation and you can run away with the energy you borrowed.
NB: The message above might reflect my opinion right now, but not necessarily tomorrow or next year.
Matter and antimatter are thought to have existed in equal amounts at the beginning of the Universe
yes, both zero at the beginning.
Creation of matter from zero matter is a violation of the second law of thermodynamics. Not that I say that you are wrong, just that it doesn't seem likely that both are right.
The simple answer to that is that the second law of thermodynamics is a statistical law, not an absolute one. Entropy in a system can increase with time, but the overall trend is always for entropy to increase. You can see the universe as a temporary statistical blip.
The more accurate answer is to observe that there are issues with the understanding of time itself implied by your observation. On the usual model of the big bang, time itself came into existence at the big bang. Because there was no "before" the big bang, the rate of change of entropy is undefined at the point of the big bang -- it would be the gradient at a singularity, and there's no such thing, so the second law of thermodynamics is meaningless at that point. (And of course even that is a simplification, because phrases like "came into existence" assume time's arrow, which is pretty hotly disputed).
Quidnam Latine loqui modo coepi?
There is a lack of symmetry in the creation of matter and anti-matter.
How do we know this? How do we know that a distant galaxy isn't completely made of antimatter? Does anti-hydrogen fusion in an antimatter star produce a different spectrum than normal hydrogen in a normal matter star?
When the Big Bang happened, both matter and antimatter were created. A goodly amount of it found its opposite and annihilated back to energy. However, the universe was expanding at the time. Eventually the universe would be big enough that a particle and antiparticle could fly away from each other and never meet. There could have been regions where matter predominated, and regions where antimatter did. Maybe the empty spaces between galaxies is where the particle/antiparticle density was roughly the same, and the galaxies are where one type predominated.
When our name is on the back of your car, we're behind you all the way!
How do we know this?
We know this by looking for gamma rays produced by matter/anti-matter annihilations. The solar wind does not annihilate with out atmosphere so we know the sun is made of matter. This same wind does not annihilate with the interstellar medium in the galaxy so that is made of matter. No other star has visible annihilation lines with this medium either so we can be sure the entire galaxy is made of matter. Further out out galaxy does not create annihilations with the medium in the local super cluster of galaxiesand neither does any other galaxy so we know that the local super cluster is all made of matter.
To go further afield is harder since at this point the distances rule out detecting gamma rays from the incredibly sparse intergalactic medium (at least this was true several years ago - perhaps astronomers can do better now?). So instead what you can do is look at galactic collisions. No colliding pair of galaxies emits gamma radiation consistent with annihilation events so either the universe is really perverse and somehow no pair of colliding galaxies is ever a matter/antimatter pair OR there are no anti-matter galaxies out there to collide with. So while it is impossible to rule out that there might be one or two anti-matter galaxies hiding in some distant corner of the universe there are clearly far, far more matter galaxies than anti-matter ones.
Actually there is. Of course it is only interested in thermal energy but nevertheless it is there. One of the most beautiful bits of mathematics, Nöther's Theorem, shows that for any symmetry there must be a conservation law (or vice versa). For energy the cause of the conservation law is that the laws of physics are all symmetric under translation in time i.e. the laws of physics today are the same as they were yesterday. So while the reason for energy conservation has nothing to do with thermodynamics it is still stated as its first law.
It's not just time: how does anything exist if there is no space?
This is incorrect. All currently known laws become meaningless as all your variables go towards infinity. This doesn't mean there are no laws - simply that we lack the theory to describe them in such extreme conditions.
It's the "what's infinity * infinity? Infinity!" - it doesn't really describe anything real. Of course, this situation changes dramatically if we could show that the variables didn't go to infinity, but were bounded in some fashion. Presently, we can't though.
Yes, from an "anthropic principle" perspective you've pretty much got to somehow end up with a universe with a matter/antimatter imbalance in order to have folks to see it. The interesting physics question, however, would be to understand how said necessary matter imbalance was produced. For example, perhaps matter and antimatter behave exactly the same, and we're just in a local "bubble" where early-universe statistical fluctuations coughed up a bit more matter. On the other hand, maybe we can find differences in the properties of matter and antimatter (which experiments like this indicate) that might allow one to be preferentially produced over the other.
Who's on first, and didn't ask what was worse. I Don't Know didn't ask what was worse either.
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun