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Neutrino Data Could Spell Trouble For Relativity
Science News has an exploration of the deeper implications of neutrino oscillation, one experimental confirmation of which we discussed last month. "The new findings could even signal a tiny breakdown of Einstein's theory of special relativity. ... MINOS [for Main Injector Neutrino Oscillation Search] found that during a 735-kilometer journey from Fermilab to the Soudan Underground Laboratory in Minnesota, about 37 percent of muon antineutrinos disappeared — presumably morphing into one of the other neutrino types — compared with just 19 percent of muon neutrinos. ... That difference in transformation rates suggests a difference in mass between antineutrinos and neutrinos. ... With the amount of data collected so far, there's just a 5% probability that the two types of particles weigh the same."
This isn't trouble, we already know there are problems with the theory, we just don't have any measurements that give us an idea of how to fix it (of course the theory works well enough in most cases). Any measurements like this that give us something unexpected are great things, they can give us a more accurate picture of how the world is, help the theory become more accurate. Always look for the flaws in your theory, for that is where the greatest discoveries are hidden.
Qxe4
It's already widely known that Relativity is just a model... much like the rest of physics. It's extremely accurate and useful for dealing with many areas, but breaks down somewhat when dealing with very very small things. Hence the great desire to develop a more unified theory! So, the summary is a little bit on the sensationalist side of the street.
The research is very important, though!
Let me try to find a lay-person analogy.
A chef theorized that there was a counter-part to bacon. We'll call it turkey bacon. We traditionally thought that Turkey Bacon was the direct opposite of Pig Bacon. Where Pig Bacon was delicious, Turkey Bacon was healthy. We decided to do some research on how Turkey bacon and pig bacon is received by the consumer. Recent taste test show that turkey bacon is not, in fact equally as healthy as pig bacon is tasty. This ruins the grand unified theorem of HTB (healthy tasty breakfast).
The only remaining explanation is there might, in fact, be a third type of bacon... i.e. a cow bacon or chicken bacon. If we discover this new type of bacon, it might completely revolutionize the Bacon Lettuce Tomato sandwich.
amirite?
Ok. I read the article and I'm still confused. I understand why different mass for particles and their antiparticles would violate CPT, which is obviously major. But I don't see how this violates special relativity. Why does this violate special relativity?
From the article, "there’s a 5 percent probability that the two types of particles weigh the same." Except, that would require a Bayesian statistical analysis and a prior. The thing to remember about confidence intervals is that the interval is random while the true value is stationary, so if you want to make statements about randomness, you have to make statements about the interval. Example, "An experiment conducted this way would find more muon antineutrinos than muon neutrinos disappear 95% of the time."
Second, we think there are infinities in the universe, and infinities tend to be catastrophic in the real world. In fact, classical mechanics met it's catastrophe in an infinity. It is unlikely that all the infinities that are created between quantum mechanics at the atomic scale and relativity at the universal scale can simply be normalized out, and black holes are not going anywhere until general relativity is fixed.
Then of course we havethe hacked dark matter née aether to make everything work out and match the theory. In light of these three things, any new data, especially new data the violates current theories, are not problem buy jewels. Jewels that will help us refine, and supposed depose, old theories. It is why we still train scientists, and laught at those that think the world is so boring that there is nothing left to be discovered. Fortunately for those that are curious, nature has new surprises every day. I would hate to live in a world where the special theory of relativity was gospel. Such a world would so boring that I would probably be thinking not of what wonders will come, but how life can be ended.
Especially since I squandered my youth solving those god forsaken equations.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
Should I be preparing for Unforeseen Consequences?
If I recall correctly CPT presumes the correctness of Lorentz invariance. And Lorentz invariance is one of the bedrocks of relativity. In other words CPT comes about from assuming your theory is Lorentz invariant and if CPT were violated it would mean Lorentz invariance is violated as well (check out Physical Review Letters 89: 231602 by Greenberg, O.W, which shows CPT violation implies Lorentz violation).
There's always the possibility that this is just a variation of the Heisenberg uncertainty principle at work. Maybe it all works, we're just gumming it all up by trying to be "God".
:).
No, I'm not saying we shouldn't try, just that we may discover we're the variable.
I remember going crazy troubleshooting a circuit with an O-Scope and the freakin' thing would more-or-less work while I was monitoring the signals. Turns out it was a capacitance issue and the probe was introducing enough capacitance to make it work, but not consistently and seemingly 'random' - but really depending upon the relative position of the scope probe and how close to the tip I was choking it when measuring. Ever since then I've had a real appreciation for Werner
They are wrong on a universal scale. This has been proven, and indeed it is where things like relativity start to come in. We have measured things that go against the predictions that Newton's laws make. That would mean they've been falsified. ...
So why the hell do we still teach them?
Well because on the scale we normally work on, Newton's laws simply and accurately describe how things works. You can go out yourself and test them in any number of ways and you'll find that as accurate as you want to measure, they are dead on accurate. When dealing with the scale of things humans normally do, they are an excellent set of rules for calculations.
Thus more accurately put they aren't wrong, they are just a simplification that works within certain bounds. They do not fully describe motion and gravitation on every level, in every case. They break down for very large and very small scales. However they are an excellent simplification for anything less than, say, a planet in size and anything above the atomic level. That would include basically everything you are ever likely to work with.
So they are very much correct, all you have to do is put a couple constraints on their use.
Simplified models like that are wonderful too. Even if they don't explain everything, they allow for calculations to be done in an easy fashion on things we care about. Some day we may discover a truly complete law for motion, that covers all cases from the smallest to the largest. at all speeds, in all frames of reference and so on. There may be nothing left out. It also may be several pages of dense calculations. Instead of that, when dealing with a normal, human scale, we'll still use Newton's laws, something you can express in a couple characters and work out in your head if you are good. An exceedingly useful and accurate simplification.
A similar example would be the Ideal Gas law. When you look at it, it is clearly wrong. Reason is you plug in numbers for something like H2O at room temperature and the result is not what you actually get. It does not show it becoming a liquid. Yet again we use it. Why? Because so long as the substance you are talking about is a gas in the temperature and pressure range you are working at, the Ideal Gas law gives you a very easy, highly accurate, way to calculate things about it. It is a simplification, hence why it is called "Ideal Gas" instead of "Real Gas". That doesn't mean that it isn't accurate and useful within some constraints.
So I can see the same being true with relativity. While we have already found cases it doesn't explain (see quantum gravitation), that doesn't mean it isn't useful within certain constraints. As our knowledge progresses, we will know precisely what those are.
If the interactions of particles are thought of as a movie, CPT symmetry requires that whatever physics occurs during the show must be the same whether the film is run forward or backward (time), viewed through a mirror (parity) and repopulated with each particle being replaced by an antiparticle (charge).
This is unclear at best. CPT symmetry says that when the film is run backward AND seen through a mirror AND all particles are replaced with the anti-particles (and vice versa) then the physics should be the same.
If you change just one, for example by running the film backward but without the mirror or the the particle exchange, or if you change two, for example, running the film backward and with the mirror but no particle exchange, then the physics will change.
We don't see the world as it is, we see it as we are.
-- Anais Nin
I think we need to reroute power through the main deflector dish to correctly mask the neutrino particle dispersion.
Found a pdf of calculus notes on northwestern.edu which shows what I was talking about.
But a theory is more than just that, it's a mental model of reality, the context for sensory input. Einstein's General Relativity and Newton's Laws of Motion are fundamentally different: Newton took time and space to be a passive background, while Einstein made spacetime an active participant in events. The two theories don't just differ a little bit on their results, they represent fundamentally different ways of looking at reality.
But in a way your professor was right: a theory is "just a" tool for understanding reality, in the same way as you brains "just" allow you to think.
Forget magic. Any technology distinguishable from divine power is insufficiently advanced.
This article confuses things a bit, I think, in saying that this represents a problem for SR (or even GR).
SR say that the speed of light is the same in all frames of reference; that, in fact, is all it says, when you get right down to it. The principles of relativity, homogeneity and isotrpoy are assumed in both classical mechamics and QM as well, mostly, I suspect, because we can't really see why it should not be the case.
Where the problem is, really, is in QM - things like anti-particles are QM constructs, and so is the assumption that they weigh the same as their counterparts; the apparent observation, that anti-neutrinos have another mass than the neutrino, is very surprising for quantum mechanics and does not fit very well into the currently accepted theory.
Perhaps it is not so strange that QM may begin to show some cracks; SR and GR make very few assumptions about anything compared to QM. It is very hard indeed to see where one could sensibly make some changes, whereas is QM, there are so many little nooks and crannies where something murky could be hiding.