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Actually, this is my field, and what I wrote was extemporaneous. Your reply is somewhat surprising - it is too bad for you that you are so angry. I hope you don’t take it out on your family. Best wishes.

The question was why and how a neutrino can transform into different particles (electron, muon, and tau).

Neutrinos don't transform into electrons, muons or tauons. According to our experimental observations, and also according to the theoretical Standard Model (i.e., the currently accepted model of elementary particles based on the Weinberg-Salam model), there are three types of neutrinos, each mathematically "partnered" with one of the three basic leptons (i.e., electrons, muons and tauons). Thus there are electron-type neutrinos, muon-type neutrinos and tau-type neutrinos. The neutrinos are all electrically neutral, whereas their partner particles all have non-vanishing charge. Neutrino oscillations occur when a neutrino of one the three types transforms into a neutrino of one of the other types.

Superpositioned information is not ruled by relativity. "spooky action at a distance".

Quantum states that are ordinary superposition states (these are superpositions of so-called "basis" states) exhibit dynamics that are indeed constrained by special relativity (i.e., their dynamical equations are Lorentz invariant). So-called "spooky action at a distance" has to do with what are called "entangled" states - these are special types of superposition states that have the property that they can't be factored into distinct basis states. Their dynamics are also explicitly constrained by Lorentz invariance.

Lorentz invariance is an essential mathematical building block of what is called "quantum field theory" (QFT), which is the principal mathematical tool used to compute predictions regarding elementary particles. There are (literally) millions of verified predictions from experiments carried out over the past 50 years that are all consistent with QFT, and thus consistent with the assumption of Lorentz invariance.

The only experimental evidence ever produced by professional experimental physicists that suggests a violation of Lorentz invariance is the recent announcement regarding the CERN-Gran Sasso "time-of-flight" measurement. If the recently announced measurement is indeed correct, it means that Lorentz invariant QFT is "wrong" in a fundamental way, and needs to be replaced (not just modified, since Lorentz invariance is mathematically embedded everywhere in QFT), and yet, it has somehow produced literally millions of other results that are all nevertheless correct. Thus it is considered by most of us to be highly unlikely that QFT is wrong, and it is more likely that this experimental claim is mistaken.

Most of us suspect that there is a deeply hidden experimental error (since this experiment is comprised of millions of separate experimental parts, and the number of possibilities for error is combinatorically gigantic) but we are waiting with open minds. Spectacular claims need spectacular evidence: this experiment needs to be independently replicated, and then we will see what is what.

I suspect that there is a deeply hidden statistical experimental analysis error at the bottom of this, most likely due to the precision of complicated system-based determinations of distance and/or timing. There are literally millions of components that together make up this experiment, and the number of possibilities for error is combinatorically gigantic. Although there has been a tremendous amount of "noise" bandied about in the popular media about this claim over the past couple of days, there is, unfortunately, very little correct information being spread around.

The experimental collaboration team who conducted this experiment are solid, well-regarded physicists, and they, themselves, are hoping that others will find their error. If this result is correct, the implications are truly profound, although the comments one has seen in the public media have gotten this almost entirely wrong, with the usual collection of various crackpot interpretations and partial or complete misunderstandings being heard.

The currently accepted basis for explaining the behavior of elementary particles is a very specialized area of physics called quantum field theory (QFT). It is simply impossible to "explain" this briefly in any medium, especially a mainly political blog - even a great political blog such as FR. (The discussion is further complicated by the nutcases who always seems to be drawn to such discussions.) An essential part of QFT is a mathematical structure called "Lorentz invariance." This is a set of mathematical constraints on the form of various mathematical expressions that describe the different elementary particles and their interactions with each other. The bottom line is that this apparent result violates Lorentz invariance. However, ALL of our understanding of QFT goes out the window if it is really correct that Lorentz invariance is not a true mathematical symmetry exhibited in Nature. Yet, there are literally trillions of data points associated to elementary particle dynamics that have been collected over the years that are all consistent with Lorentz invariance.

A gigantic puzzle will thus emerge if the claimed result proves to be correct. Contrary to some of the unhinged and/or ignorant who write about this, there is no reluctance on the part of working physicists to consider new, even radically new, ideas that challenge our understanding. The main issue is that this result simply doesn't make sense based on the huge number of other facts that we know are true based on other measurements that have been massively replicated.

The next step is to independently replicate these results, as required by the scientific method.

A last comment: non-physicists will probably mostly not know this, but there was an almost as strange, apparently incongruous experimental result in particle physics that came out in the 1970s called the “high-Y” anomaly (“Y” is a certain physical quantity). The measurement gave values that seemed to contradict a huge part of particle physics understanding, although that result didn’t generate the public noise that this claimed result has. After a lot of confusion in the particle physics community, the “high-Y” anomaly result was discovered to be due to an experimental error.

In this experiment the neutrinos were not accelerated by the experimental equipment. There was acceleration of something else, however: the neutrino beam is produced by accelerating a beam of protons to an extremely high speed (400 GeV/c - this is actually their mean momentum value) - the acceleration of the protons is accomplished by controlling precisely configured magnetic fields in a device called a synchrotron (the CERN Super proton synchrotron). The accelerated protons are then allowed to collide with a specially prepared “neutrino production target” made up mostly of graphite. There the protons decay into a number of other types of particles, the important ones of which are called pions and kaons. There is a natural pion/kaon decay process into muons and their associated neutrinos that then takes place along a long, evacuated tunnel. A variety of decay products are “stopped” using various materials, and what finally results is a highly pure beam of neutrinos, that continue to propagate forward. (There are actually three types of neutrinos that we know about, and this beam is almost purely (~97%) made up of so-called muon neutrinos.)

This thread is weaving in and out of different topics. I’ll leave all but one alone: the absurd claim that “relativity is a scam.”

I am motivated to write something because I strongly believe in the conservative cause, and I don’t want to see this cause damaged by the appearance of flat earth-type nonsense on Free Republic, which is an embarrassment. We must vote Obama’s enablers in Congress out of office in November, and can use all the support we can get. When nonsense regarding established, entirely non-controversial (frankly, baby level) physics appears uncontested on Free Republic, the job of gaining converts to conservatism is made much more difficult.

No, “relativity” is not a “scam.” Although it is not possible to properly and fully explain this topic in a brief posting in a blog, especially without mathematical equations, there are a few things that can be pointed out. Specific predictions of special relativity are confirmed literally thousands of times every day, and have been for decades, in the form of the vast amount of data from particle accelerators located in the US and in a number of other countries around the world. These are measured data that are in agreement with the predictions of special relativity, and that are not in agreement with the predictions of any other physical theory. These data are produced all the time at places like SLAC, Fermilab, Brookhaven, etc. Special relativity is manifested by a very specific set of mathematical constraints on the forms of the differential equations of motion of the elementary particles (these constraints are collectively referred to as Lorentz invariance, which means that a certain functional of elementary particle fields (a functional is a generalization of a mathematical function) known as the Lagrangian density, transforms covariantly under the application of arbitrary elements of the Lorentz group – equivalently, that the action transforms invariantly. “Covariant” transformation refers to the tensor structure of the elementary particle fields upon which the Lagrangian density depends, which is beyond the scope of this post.). One calculates from the solutions to these equations of motion various physical quantities of interest, such as scattering amplitudes, distributions of energy with respect to time and angle, particle decay widths and many others quantities. In particular, the lifetimes of literally hundreds of identified resonances and particles are calculable, and these predictions of special relativity are all in accord with the measured results (actually, to be technically precise, the data are in accord with the predictions of what is called “quantum field theory,” which is a self-consistent melding together of special relativity and quantum mechanics. The predictions of one quantum field theory in particular, quantum electrodynamics, provide closer agreement with experiment – to many decimal places – than any other physical theory thus far developed.) General relativity is likewise manifested by a very specific set of mathematical constraints, collectively referred to as Poincare invariance. Analogously to Lorentz invariance in special relativity, Poincare invariance means that the underlying Lagrangian density (now including dependence on the gravitational field) transforms in a specified way under application of arbitrary elements of the Poincare group (which contains the Lorentz group as a subgroup, hence the names “special” and “general.”) Over the years literally millions of data points have been accumulated that are in agreement with the predictions of special relativity. There is less data available with which to assess the predictions of general relativity (for practical reasons that are well understood, related to the differences between experimental astronomy and cosmology versus experimental particle physics), but there are a number of experimental confirmations of the predictions of general relativity that are not explained by any physical theory other than general relativity. I will not take the time or space to enumerate these, but I will only mention the famous prediction of the shift of the perihelion of Mercury, which decades ago was the first experimental result found to be in agreement with general relativity (and in disagreement with non-general relativistic gravitational theory). Regarding those confirmations that I am not taking the time to list here, there is MUCH more explanation of the agreement between theoretical predictions of relativity and experimental results provided in a clearly written book (“Was Einstein right?”) by Professor Clifford Will. Cliff wrote this book for a popular audience many years ago in an attempt to fight the spread of flat earth-type nonsense. The contents of that book have been supplemented by much more experimental confirmation since its publication almost 25 years ago.

VOTE THE BASTARDS OUT IN NOVEMBER.

Thanks for that.

My pleasure.

Hope you stick around. Cheers!

I believe that Free Republic is of extraordinary importance to our nation, particularly now, during this truly horrible period when our beloved country is in the grip of the most dangerous, evil regime in its history. In fact, irrespective of how bad certain previous administrations may or may not have been, I would never in my life have imagined that the word "regime" would be appropriate to describe any U.S. government, but there is no more apt word. The country in which I grew up, which provided generations of good people with security and hope and opportunity, is in danger of being irreversibly damaged. Caliph Hussein Obozo will hopefully be voted out of office in 2012, but in the meantime his enablers in Congress must be stopped.

VOTE THE BASTARDS OUT IN NOVEMBER.

The author of the quoted article, "Mysterious Q Balls -Created in the Heat of the Newborn Universe: Are They SciFi or SciFact?", a person called Casey Kazan, wrote in his piece:

“Inside a Q-ball, the familiar forces that hold our world together don't exist…”

As is the case with far too many popular articles that purportedly deal with physics topics, this quote is inaccurate, and very misleading. It is so misleading that some posters here, in attempting to discuss the article, in turn wrote passages such as

[ A q-ball ] “is a region of space where the laws of physics are repealed…”

and

[ a q-ball ] “is in the physical world but ... does not adhere to the laws of the physical world…”

None of this is remotely accurate, although the fault lies with the author of the misleading “popular” article and not with the freepers who merely took him at his word. Q-balls do not "depart" in any way from established facts of physics, and q-balls are not some “new” attempt to “get funding,” and, in fact, they aren’t new in any sense at all. They are explicit mathematical solutions to the differential equations of motion of certain quantum field theories describing the interaction dynamics of specific bosonic fields, first worked out more than 40 years ago. The name “q ball” is due to the fact that these particular mathematical solutions exhibit spherical symmetry (hence “ball”) and possess a non-vanishing type of “charge,” which is often designated in physics by the letter “q.” (The charge in this case is not the same as electrical charge.)

The first q ball-type soution to a quantum field theory was derived in 1968, but the first physicist to work out all the mathematical details required to prove that such states are stable against the phenomenon of quantum mechanical tunneling was Sidney Coleman at Harvard in 1986 (he used a clever technique known as the “thin shell approximation” with which he derived the analytical expressions that comprise his solution, which he named "q ball"). Sidney died a few years ago, but his calculations, clearly presented in published articles, have been independently reproduced by hundreds of physicists around the world since then (including different derivations than the original). There is absolutely nothing controversial about any of this. It is completely inaccurate to imply, as the author of the “popular” article does, that ordinary forces “don’t exist” in a q-ball. On the contrary, the particle field configuration called a q-ball behaves the way it does precisely because of the laws of physics. Due to the peculiar (but theoretically and experimentally well-established) quantum mechanical properties of bosons (physical states that possess integral values of intrinsic angular momentum, also known as spin), it turns out, as Sidney showed years ago, that certain solutions to the field equations can arise that describe bound configurations of bosons which are characterized by a potential function that has a value smaller than would be the case for the corresponding free (i.e., non-binding) potential. Thus, the bound state is the lowest energy state - unusual, but fully consistent with established properties of the forces that determine the dynamics of elementary particles. It will be interesting to see if these theoretical solutions can be experimentally confirmed.

In the meantime, it is very unfortunate that the author of the popular article so completely mangled this point, misleading some posters here as a result. Many scientists have had the experience of popular journalists messing up descriptions of their work with absurd linguistic flights of fancy - this is yet another example.

OK, I see your point. How about if I said ‘a chaotic system is a system in precarious balance a non-chaotic system has an “entrenched” (for lack of a better word) balance?’

That sounds like a perfectly good qualitative description - it captures the essence!

Wow! that’s a great response. Thank you.

My pleasure.

If I have understood the essence of your explanation it is that ‘chaos’ (in the context you describe) is roughly synonymous with ‘instability.’ A ‘non-chaotic’ system is a relatively stable system.

Just as is the case for the word 'chaos,' the word ‘stability’ has a very technically specific meaning in physical dynamics. Rather than using the word stability, I would prefer to say that a chaotic system exhibits exquisitely sensitive dependence on the so-called boundary conditions to the solutions of the underlying equations of motion of the system. Phyiscal systems that are not chaotic are decribed by equations of motion the solutions of which do not exhibit such extreme sensitivity to boundary conditions. (“Boundary conditions” are constraints that need to be specified in order to obtain particular solutions to differential equations – unlike algebraic equations which don’t require additional information in the form of “boundary conditions” in order to be solved.)

[ The reason I want to avoid using the word 'stability’ here is that it is entirely possible for a non-chaotic system to exhibit an "unstable" solution. As an example, one way in which a perfectly non-chaotic physical system, such as one described by linear differential equations of motion, can possess an unstable solution is if a quantity called the "potential function" (this quantity is part of the equation of motion) is what is called "unbounded from below". ]

Some folks have asked about the meaning of the word chaos in the quoted article. In the context used by the author of the paper referred to in the article, the word "chaos" has a very specific, technical meaning. This technical meaning of the word "chaos" is different from the regular usage in everyday speech - for instance the crappy chaos we see all around us caused by Obozo and the blithering idiots in the Congress who support/enable him is one usage of the word, but the way we use the word 'chaos' in physics is different.

In physics, the evolution of a physical system is determined by the solution(s) of an equation (or a system of equations) called the equation(s) of motion. For most interesting physical problems, the equations of motion are differential equations. In the case of those physical systems the evolution of which is determined by linear differential equations, the solutions to the equations, irrespective of whatever other characteristics they may or may not exhibit, do not exhibit the property of chaos. In those cases for which the equations of motion are nonlinear differential equations, it is sometimes the case that the solutions will exhibit the property of "chaos." This technical term means something specific: Associated to the equations of motion of a physical system is a mathematical "space" - the "place" in which the solutions to the equations evolve. This space is generically referred to as "phase space." Solutions of the equations of motion yield what are "trajectories" in this phase space. There is a particular type of technically-defined quantity, called the "Lyapunov exponent," associated to different such trajectories in phase space. For a given system of equations of motion, there is actually a set of Lyapunov exponents, called the Lyapunov spectrum. For this spectrum there is a largest (sometimes unique) Lyapunov exponent. Depending on the value of this largest Lyapunov exponent, the system is called "chaotic" or not. Specifically, if the largest Lyapunov exponent is a positive number, then the system is "chaotic" (most of the time - this is a very technical subject with a large number of qualifications that are not possible to go into in a blog.)

So much for a (partial) mathematical characterization. What does it mean qualitatively if a system has a largest Lyapunov exponent that is positive, and the system is thus (usually) chaotic? Roughly speaking, if a system is "chaotic" in the technical sense of physical dynamics, it means the following: if you let the system evolve under a given set of initial conditions, you will see a certain behavior: call this the "default behavior.". If you "nudge" the system a "little bit" (this roughly means that you only slightly alter the initial conditions on the solutions to the differential equations of motion), and if the system is chaotic, the result will be a BIG change in that default behavior. On the other hand, if the system is NOT chaotic, a "little nudge" will produce only a little change in the behavior of the solution. (Solutions describing non-chaotic systems, such as all solutions to systems described by linear differential equations of motion, do NOT behave this way: if you nudge things "a little," the solutions also only change "a little.") Another way of describing a system that exhibits chaos is to say that, in a chaotic system, two trajectories in phase space that are initially "very close" (this can be defined mathematically rigorously) together, will separate from each other exponentially quickly as a function of time in phase space.

This article exhibits the pleasing characteristic of - at least - not displaying atrocious errors of scientific fact, as do far too many popular articles written about ongoing research.

Incidentally, one poster wrote above that the author of the article states without qualification with respect to the presumed black hole 'Sagittarius A' that its "Schwarzschild radius around the supermassive black hole extends about the same distance as the orbit of Mercury." This is an established fact, described in, among other publications, Schodel, R., et al., Nature 419, 694 (2002) and Ghez, A. M., et al., ApJ 586, L127 (2003).

In the referenced article, the authorship of which was attributed to unnamed "NPR staff," there appears the following passage:

"...and some even think entanglement may explain things like telepathy."

A couple of posters have noticed this passage, and used it as the basis for a condemnation of the professional scientists working in this area, going so far as to imply that those scientists are "idiots."

I want to point out that this absurd passage in the article doesn't actually quote any trained, professional physicist who actually earns a living by working in the field of Quantum Information Science (nor does it quote any professional scientist of any kind for this passage). In fact, this passage doesn't quote anyone at all. There is probably a very good reason for that: I suspect that "NPR staff" made it up (because they believe it), and that "NPR staff" did not hear any working physicist utter this inane, meaningless comment. I have never in my entire career heard a single one of my fellow physicists ever make such a statement about "telepathy," whatever telepathy is, assuming it is even a real phenomenon, which I doubt. The topic of the article, quantum teleportation, is an actual physical phenomenon that has been independently reproduced in a number of physics laboratories around the world over the last few years, and has nothing whatsoever to do with so-called "psychic phenomena." This work is real physics, and has nothing whatsoever to do with "telepathy," for which there is currently no scientific evidence available.

(Incidentally, although this phenomenon, to which we have given the name "quantum teleportation," has indeed been demonstrated in a few laboratories (beginning with demonstrations at the University of Innsbruck and at Caltech in the late 1990s), one shouldn't fall into the trap of associating this with what appears on Star Trek. The experimental demonstrations that have been performed (for which, by the way, there is a mathematically rigorous, theoretical basis) have involved "teleporting" small numbers of elementary particles under carefully controlled conditions. We are a very long way away from doing anything remotely like what appears on Star Trek.)

I should point out that this article, as is the case with far too many popular science articles, has various misleading and inaccurate statements. To wit:

And so space-time - the malleable fabric whose geometry can be changed by the gravity of stars, planets and matter - was born. It is a concept that has served us well, but if physicist Petr Horava is right, it may be no more than a mirage.

This is astoundingly wrong. Petr's work implies no such thing. His explicit calculations simply take account of the fact that, based on an assumption that there was a very high average temperature in the early universe, Lorentz invariance is violated at finite temperature. As a result, he makes use of a set of techniques that are together called "finite temperature quantum field theory," in which Lorentz invariance is violated, rather than zero temperature quantum field theory, in which Lorentz invariance is not violated. (Both finite- and zero-temperature QFT are very well known. The fact that Lorentz invariance is broken in finite temperature QFT is also very well known. Basically (oversimplifying things a bit), the new idea was to apply this method to the explicit calculation of interactions involving gravitons in the early universe.) There is certainly no notion, quantitatively or qualitatively, either in the original Horava paper or in any of the subsequent papers that cite it, of spacetime being a "mirage." The author of the popular article should have had his article vetted by a physicist prior to releasing the final copy. (Petr Horava would never have put things the way the author of the popular article did.)

Thanks for the explanation.

My pleasure.

“E8” — I’ve seen that before! (Lisi)

The "E8" in my name refers to a so-called "Lie group," a type of mathematical structure that plays an important role in the physics of elementary particles (Lie groups have many other uses in other fields, as well). "E8 cross E8" refers to what is called the ("semi-direct") tensor product of two copies of this Lie group - this product of groups has played a crucial role in string theory. My use of this as a name is in this context.

Howard Fineman has for several years been a regular guest on Keith Olbermonster's offensive propaganda program. I regard Fineman with the utmost contempt. I have no respect whatsoever for Fineman, nor do I trust his judgement in assessing anything under the sun.

It really is not whimsical. What Petr did in his initial paper is justified, and, in retrospect, it is suprising that none of us thought of doing it earlier. It is not really possible to go into the full details of this in a forum such as a blog, but the main point is that, at “finite temperature” (this the jargon we use to refer to physical systems at temperatures above zero), Lorentz invariance (”Lorentz symmetry,” as it is referred to in the article) is automatically violated. The reason is that the mere statement that there is a finite temperature at all implies that there is present in the problem a large number of particles in the “background” that together make up what is referred to as a “heat bath.” The word “temperature” actually refers to a statistical measure associated to this background heat bath. However, this is the reason that Lorentz invariance is broken: the aggregate properties of the large number of particles that, together, make up the heat bath, among many other things, implicitly pick out a so-called “preferred direction” in spacetime. This “preferred direction” (technically, this is the direction in spacetme towards which the velocity 4-vector of the heat bath points) intrinsically breaks Lorentz invariance. What Petr did in his paper is technically justified. Other physicists later showed (as described in the article) that the original paper didn’t properly reduce to general realtivity (whcih DOES exhibit Lorent invariance) at low temperatures, but that defect of the original Horava idea has since been fixed. This is all still very much research in progress.

Hmmm. I don’t know how anyone of Human heritage could be a Harry Reid supporter. Horse heritage - maybe: at least, a certain part of a horse.

“Courteous and kind,” eh? Interesting. If you count up the total number of times the Obama-drooling, liberal stenography “press corps” exhibited kindness and courteousness to W during the entire 8 years of his presidency, and attempt to calculate the reciprocal of that number, you end up with infinity.

I am not a physicist but I grasp the concepts of physics.

Let me tell you something, your job/work in physics is secure, in fact it will extend onto infinity.

Keep up the good work.

Regards,

Thanks for the comment. As a physicist I feel quite secure as such. I wish I could also feel secure about the country as a whole. However, given the Obominable mis-administration of Obozo ...

//the discovery of the Higgs, sadly, won’t solve this problem//

Why is that a sad thing?

Good point - you got me there. I should have written that it would be sad for me, and sad for my colleagues. In fact, it's probably a good thing, as it means there remains a lot of work to perform. ;)