Severian

I think it is quite impressive. There are no problems with safety or nuclear proliferation either, since the reaction is not self sustaining.

The closest thing I can find from Deutsch is http://arxiv.org/abs/quant-ph/0104033 and I presume he would cite his own paper, so I suspect his publication isn't out yet. Maybe it was a talk at a conference?

Which theories are you taking about? The Standard Model, for example, has made no wrong predictions at all! In fact that is one of the big problems with particle physics at the moment - the Standard Model doesn't give us much leeway for going further. General relativity has also never made wrong predictions because we have been unable to test it on a quantum level. We don't have a consistent theory of quantum gravity (gravitons) yet. Yes it does. It must have at least one prediction better than current theories. As Swanson has already pointed out Copernicus' theory explained something which was previously not explained (just modeled). If you could explain some part of current physics currently only modeled with a theory with very few parameters, we would be willing to listen. For example, if you had a hadronization model with one or two parameters, I could guarantee you an audience of 100s of enthusiastic experimentalists. Only because the crackpots are too stupid to come up with anything semi-consistent. I do agree with this, but there has to be some level of standard. Look in the speculations forum and you will see that the majority of the suggestions can be discarded with just a moment's thought.

You could very easily have a non-unitary theory by placing current theories in a box. When the wavefunction of a particle leaves the box, you have a unitarity violation because the probability of finding it somewhere in the box (where the theory is defined) is no longer one. That may sound trivial, but in essence this is what a discovery of non-unitarity would tell you - that you have forgotten to include something (like an extra dimension). Or at least, that is how it would be interpreted...

Are you meaning to imply that I said he called the whole Bible a myth? I did not.

Sorry, I missed fermion's reply to this. Actually I did answer your question, and everything you should need to satisfy you is in my post. Semi-leptonic pion decay is the decay of a W. How else are you going to make the leptons? The charged pion, for example, is [math]u \bar d[/math] which decays into a [math]W^+[/math] and subsequantly to mainly [math]\mu^+ \nu_\mu[/math] (since the initial state is spin-0, we need a heavish object in the final stat to give a spin flip, so the electron final state is suppressed, and the tau is too heavy). So everything I posted earlier was relevant to charged pion decays. But I am happy to go through it in your scenarios. That is fair enough, except that I say that we do care about the neutrino, since it is the mismatch between charge lepton and neutrino flavours which is important in any leptonic oscillation. Up to here I am with you. I disagree here slightly. The photon is not required. I can conserve energy and momentum perfectly well by keeping intermediate particles off-shell. The rate for [math]\pi^+ \to l_1^+ \nu_\mu[/math] (where [math]l_1[/math] is the lightest charged lepton mass eigenstate) is non-zero even without an extra photon (though it is very suppressed because of the small mass of [math]l_1[/math]). But this isn't very relevant to the discussion. This was also true for W decays. In fact, it is true for pions, only because of the W in between... The problem is that you are not comparing like with like. Both of the above are completely fine, but they are different effects that each can happen. Let us assume you measure the final state particle flavours, rather than their masses (we could do their masses later if you like). For example 1, there are 3 possible final states (since the neutrino oscillates): [math]\mu^+ \nu_\mu[/math] or [math]\mu^+ \nu_e[/math] or [math]\mu^+ \nu_\tau[/math], but for any individual event you only see one of these. For example 2, there are also 3 possible final states (since the charged lepton oscillates): [math]\mu^+ \nu_\mu[/math] or [math]e^+ \nu_\mu[/math] or [math]\tau^+ \nu_\mu[/math], but again for any individual event you only see one of these. So the final states in your examples only match for [math]\mu^+ \nu_\mu[/math] so that is the only one you can compare, and since the oscillation in each involves the same entry in the PNMS matrix they will have identical cross-sections and you have your equivalence. In other words, when thinking in philosophy 2, you see e.g. [math]e^+ \nu_\mu[/math], how are you going to persuade your philosophy 1 minded friend that this wasn't just the production of [math]e^+ \nu_e[/math] followed by the oscillation [math]\nu_e \to \nu_\mu[/math]? (Notice both processes have the same rate.)

I agree with ParanoiA, but I do feel that 'attempted murder' is too harsh for what they did. Surely it was assualt at most.

I agree that it is perfectly acceptable for a lecturer or teacher to express their opinions about thier own religious views at any time, and therefore one should not be fired for calling the bible 'a myth'. However, I get the impression from the article that there was more to it. First of all, it says "Bitterman said that he can think of no other reason college officials would fire him", so it is clear that he doesn't really know why he was fired. And since the the college refuses to comment it is a little bit speculative to suggest that he was fired for calling the bible 'a myth'. From the second article, it seems that he was being insulting to the students, and was so abusive to one student that "she left class in tears". She claimed that he had been insulting toward her and told her to "pop a Prozac." It is kind of difficult to tell what happened, but if he was being abusive to the students, or even just trying to persuade them of his own worldview, I would regard it as a sacking offense. I would certainly get fired if I started a sermon on Christianity in one of my lectures. So unless you know the facts of the case, I suggest we postpone the moral outrage for now.

A laptop looks like a bomb. Lots of wires and plenty of room for explosives. Maybe we should just start shooting people who are stupid enough to bring laptops into airports?

A few points: 1) She wasn't getting on a plane, so didn't need to go through security. 2) Security officers in airports should at least have some clue of what a bomb would look like. I have no objection to them checking it out, but any 10 second inspection would have resulted in any sane official saying 'Sorry to have bothered you Ma'am'. 3) Why is this more blatant than carrying a laptop? A laptop has a lot more circuitry and plenty of room for plastic explosives in it.

I don't mean to derail the thread away from Yourdadonapogos' hatred of his family, but one of Webster's definitions of religion is "a cause, principle, or system of beliefs held to with ardor and faith", which would definitely qualify atheism.

In some sense there can never be a Theory of Everything. Even if we can describe the universe with one equation, we will still wonder 'Why that equation?'.

From the article: In some ways I don't object to tightened anti-terrorist security. But if you are going to start pointing machine guns at people, you really need to give the people with the machines guns some decent training.

Think of it this way. There are two different ways of looking at things. So let's consider them one at a time. 1. Let's write the fields in the interaction term as the charged lepton mass eigenstates and let the neutrinos take all the PNMS matrix. This is the standard way of thinking, and since it is mass eigenstates which propagate, the charged leptons produced by the interaction will not oscillate but the neutrinos will. Now, lets let a W decay via [math]W^- \to e^- \bar \nu_e[/math]. The e- is a mass eigenstate so doesn't change but the neutrino oscillates, say to [math]\bar \nu_{\tau}[/math] before we detect it. So effectively we have seen a [math]W^-[/math] decay to [math]e^- \bar \nu_\tau[/math], and interpret that as a neutrino oscillation. That was all standard. 2. Now let's imaging writing the fields in the interaction as being the neutrino mass eigenstate and but the PNMS matrix into the definition of the charged leptons. This is not the way it is usually thought of: now the neutrinos don't oscillate but the charged leptons do. This time, let the W decay via [math]W^- \to \tau^- \bar \nu_\tau[/math]. The [math]\bar \nu_\tau[/math] is a mass eigenstate so doesn't change but the charged lepton oscillates, say to [math]e^-[/math] before we detect it. So effectively we have seen a [math]W^-[/math] decay to [math]e^- \bar \nu_\tau[/math], exactly as in case 1! How do we interpret this? We could interpret it as a changed lepton oscillation, but that is not the usual way of looking at things. We normally interpret it as a neutrino oscillation. In other words, the language that we have conventionally use to write the lagrangian in makes us interpret this mixing only as neutrino oscillations and never charged lepton oscillations.

The issue is that the neutrino mass eigenstates and charged lepton mass eigenstates are not aligned. Look at the terms in the lagrangian which contribute to neutrino mixing. If I use the mass eigenbasis, then the neutrino mixing matrix is sitting in the charged current interaction term. It is not in the neutral current because it is unitary and will cancel. Now what would happen if our charged lepton mass eigenbasis was not the same as the charged lepton interaction basis? Exactly the same thing - using the interaction basis, the mixing matrix would move into the charged current interaction - the same place that we moved the neutrino mixing matrix. We choose to call this matrix the neutrino mixing matrix, and define our states such that there is no charged lepton mixing. To put it another way, if there were no charged leptons, there would be no neutrino oscillations, since we could just rotate it away. It is the presence of the charged leptons which prevent us from rotating the PNMS matrix away by redefining the fields, because the chaged lepton mass matrix and the neutrino mass matrix are not aligned.

Considering that you have, in past threads, called Christians 'insane', 'morons' and 'evil' (among many other things), is it really so surprising that they want to change you? Do you think your family would be insulted by these descriptions? What about your uncle?

It is just a definition. You can move the the PMNS matrix into the charged lepton sector if you really want to. After all, the neutrino interactions you are interested in in your neutrino detectors are always vertices which include the charged lepton. So it is just convention. If you don't believe that, it is quite easy to think of a diagram for e to mu: e- emits a W- turning into a nu_e, nu_e oscillates to nu_mu, and nu_mu reabsorbs the W- to turn into mu-. In other words, your charged lepton 'oscillation' is fully described by the same quantities you use for neutrino oscillations (the PNMS matrix), so we just don't think of it as a separate phenomena (it isn't!) and don't worry about charged lepton oscillations.

Let me ask, do you think it is right that some people shouldn't have health insurance? If so, what would you do with these people if they are in an accident? Would you give them emergency medical care? If so, who pays? I would have no problem with someone (over the age of 18) refusing medical insurance, but then they should be treated as if they have refused medical attention.

I once met someone who had a rainbow eyecolor (different colors in circular bands around the pupil), but I presume that was contacts.

I personally think Hilary's scheme sounds good. It is the best of both worlds. It allows people who are happy with their current health care arrangements to continue, but ensures that everyone should have some basic healthcare plan. I wish that the UK would abandon the NHS and adopt this scheme instead. At the moment I am paying over the odds because I am paying compulsory National Insurance to entitle me to NHS care, but since the NHS is completely useless i am also paying for private healthcare.

Somehow I think it doesn't mean what I would usually take it to mean: Quantum Field Theory.... and thanks.

I agree with the OP to a certain extent, but I think the cause is slightly different. I think what is tagged as 'liberalism' in modern society simply isn't liberalism anymore. To my mind, liberalism is about tolerance - it is letting people live their lives the way they want to live it. I think this is a very admirable goal. But the modern 'liberal movement' doesn't want you to live your life in the way you want to live it - they want you to live your life in the way they want you to live it. We now have lots of lifestyle choices which are labelled as 'liberal' or 'progressive' and if you don't conform to these choices, you are somehow labelled as conservative, repressed, or just downright evil. The modern liberals make it a crusade to reform you to their right way of thinking. Religious belief is a good example. Many liberals seem to have declared atheism to be the correct 'liberal' belief, so if you have any religious belief at all, you are deemed as the enemy. Most religious people just want to be left alone to live their lives as they want to live, but this is not acceptable to the new left. Feminism is another example. There are now an accepted liberal party line about how women should live their lives. It is no longer acceptable for women to stay at home and look after the kids. Any woman who claims that she wants to, is declared to be emotionally abused into saying that she wants to, or a traitor to the feminist movement. With the enormous growth of legislation to protect my rights, I feel a lot less free than I did before...

Imagine the universe as just being a series of events in space-time. In principle, it could be that there is no governing laws which link together these events - they just are. Then you could never make any predictions about future events based on past events, since there would be no causal connection. Now, we have observed connections between events. In fact, we have gotten so good at finding patterns between these events that we can use the patterns to predict events that we haven't even observed yet. This is very useful and I am not trying to downplay that at all (it is what I do for a living after all). But, there could well be different regions of space-time (ie. groupings of events) where the patterns that we have observed are not valid, and either there is no useful pattern or it is a pattern which is very different from the one we know. That may sound far fetched, and I agree that for most events we see in our everyday lives we don't need to consider it, but it is a possibility. In fact, this is actually predicted by String Theory (for example the 'landscape', which has 'bubbles' of space-time where different vacua are manifest, giving very different physical laws). In actuality there is no reason to expect that a future event will obey the same patterns that we have observed. YT's analogy is a good one: if we had observed a coin only coming up heads, we would not be expecting it to come up tails and would have built a false theory about the possible outcomes of the coin flip. In order to build physics theories, we do have to assume that future events are corellated by past events, but this is something we take on faith. Two points: 1. I am not saying 'nothing is certain, therefore everything is faith'. As long as you preface your scientific statements with things like 'If predictivity holds for all space-time events...' or something similar, then you can make absolute statements. These are not based on faith since your statement declares itself void in the eventuality that the conditional fails. 2. Since you only have one universe to test you can make no statement about the 'balance of probability'. You cannot quantify the probability that all space-time events are corellated. What you can do, is look at the number of space-time events which you have observed, and ask what proportion of them are corelated with one another. In scientifically tested subjects, this is a very high number (~100%) so you can then claim that your next event probably will also be corelated (again, this is what I do for a living). However, you need to be careful extrapolating to areas where you have not tested this - we cannot, for example, predict the actions of individuals, so we cannot claim that conciousness is linked to physical law. We cannot predict (other than statistically) quantum mechanical decays, since they are based on random numbers. Furthermore, there is a tendancy not to count events which appear uncorelated claiming that we just don't understand the corelation yet. Finally, there is no such thing as 'reasonable faith'. Either it is belief in something which can be proven or it is not. You are simply tacking the word 'reasonable' onto your beliefs to give them false legitimacy.

A sample spectrum is in the figure of http://arxiv.org/abs/0708.3248 (only a conference proceedings, so not much detail yet).

The more mystifying thing is that people think that web advertising works. I just followed that link, and read a few stories, but now that I have closed the site, I can't remember a single ad.