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Comment LHC Magnets (Score 1) 73

Better magnetic "mirrors" and/or "lenses" for focusing beams in things like the LHC or even just an electron microscope?

Actually it is not the focussing magnets for the LHC but more the bending magnets. Doubling the field strength will roughly double the energy we could reach. However you have to be able to make several tens of kilometres of these magnets for that which means they have to be incredibly stable otherwise the machine will not work. Currently we use 9.6T bending magnets - this is no where near a world record but stability is very important.

Comment Re:Relativistic Mass is fundamentally wrong (Score 1) 347

Try using F=d/dt mv ...

Yes...and that does not work at all for relativity since you are missing the gamma factor.

F=ma doesn't work naively in any case where the mass is not constant, relativistic or not.

True but it doesn't work even when mass is constant e.g. for an instant of time under relativity because the 'gamma' factor is a correction to the velocity, and here you have acceleration so there is no simple gamma factor. You are also wrong that it is purely pedagogical because at a fundamental level we know that e.g. the mass of an electron is due to its coupling to the Higgs field. This coupling does not become larger with an increase in energy hence the electron mass remains constant. Still not convinced? Einstein himself argued against the concept.

Comment Reliability? (Score 1) 131

Never mind security, what about reliability? If I go hiking in the mountains where there is no cell phone coverage and e.g. scratch my face on a tree branch I do not want to get back to the car only to have it fail to recognize me and refuse to start. Frankly I also wonder about whether Ford are thinking clearly about this given the claim in the article that "Ford Motor Company [NYSE:F] already believes the technology can help improve privacy..". How can adding a camera to a car improve privacy? No matter what protections you put in place around the system if there is no camera there is no data on who is driving which has to be better privacy than a system which knows.

Comment Relativistic Mass is fundamentally wrong (Score 1) 347

"moving mass" here is being used for poorly named relativistic mass, which is not an invariant. For both gravitational and inertial purposes, things act like their relativistic mass in a given frame, regardless of what their rest mass is.

Actually they do not. Try using 'F=ma' with relativistic mass and you will not get far. You can only use the simple 'gamma' factor when dealing with relativistic momentum and then, at a fundamental level, it comes from the fact that the particle's velocity has to be redefined for relativity because there is no universal clock. This is not a pedagogical argument it is a fundamental physics argument: relativistic mass is a broken concept, the universe simply does not work that way and you will go wrong if you use it in any but the simplest situations.

Comment Re:Even that Sounds Wrong (Score 1) 347

That paper shows the solar neutrino problem not flavour oscillations. SuperK saw the first hints of this from atmospheric neutrinos, not solar neutrinos. However SNO was the first experiment to conclusively prove oscillations: they showed that the total flux of solar neutrinos was as expected but that only ~a third of them were electron neutrinos despite the fact that all of them started as electron neutrinos. Seeing a disappearance of a particular flavour does not prove oscillations: they might have somehow decayed or been absorbed through unknown processes. While this requires new physics neutrino oscillations was also new physics at the time so Occam's razor can not really pick between them.

Comment Re:Even that Sounds Wrong (Score 1) 347

As long as neutrinos have been known about (and even when just a postulation) they had moving mass, as they carry energy away from decays and reactions.

Actually that is not true. The Standard Model originally had them with zero mass. This was disproven in 2002 by the SNO experiment which conclusively showed that neutrinos from the sun changed flavour which meant that they had to have a mass. The SuperK experiment also had some earlier results with atmospheric neutrinos which also suggested flavour oscillations. You are also under the misconception that mass changes with speed: it does not and is an invariant quantity the gamma factor in momentum comes from the velocity changing under relativity not the mass.

Comment There is only one mass: it's invariant (Score 1) 347

You are mixing up rest mass (which neither the photon nor the neutrino has) with moving mass / impulse

No, actually I'm not: trust me I'm a particle physicist! There are two misconceptions there. First a particle does not have to have a mass to have a momentum. Einstein's favourite equation is not actually 'E=mc^2' unless you are standing still. It is more correctly written: 'E^2=p^2c^2 + m^2c^4' where 'p' is momentum. In the case of a massless particle (m=0) this is just: 'E=pc' so a photon with a non-zero energy has a non-zero momentum but ALWAYS has a zero mass.

The second misconception is that the mass of a moving particle somehow changes. This is wrong and in fact you can show quite easily (if you know relativity) that the mass is something called a Lorentz invariant which means it is the same for all observers in all inertial reference frames. The misconception regarding the mass "getting bigger" at higher velocities comes from the formula for relativistic momentum for a massive particle "p=gamma*m*v" where 'gamma' is always greater than 1 for v>0. This factor is erroneously coupled with the mass to give what some textbooks call 'relativistic mass' (gamma*m). This is WRONG! One of the consequences of relativity is that space and time get 'mixed' differently for different observers. Velocity is 'space/time' so this is where the gamma factor comes from. This is very obvious to see if you look at acceleration. The relativistic form of Newton's second law is NOT 'F=gamma*m*a' which it would be if this was just an effect on the mass increasing.

You claim that a neutrino has always mass (or more than a photon) is either plain wrong or grants you a noble prize if you can proof it.

See this paper: “Direct Evidence for Neutrino Flavor Transformation from Neutral-Current Interactions in the Sudbury Neutrino Observatory”, The SNO Collaboration, Phys. Rev. Lett. 89, 1, 011301 (2002). It is not possible for neutrinos to oscillate unless they have a mass difference which means that at least two of the neutrino flavours must have a non-zero mass. You are correct that it is likely to win the authors a Nobel Prize probably within the next few years but I'm not one of them (but I was an author on the Higgs discovery paper so that's ok! ;-).

Comment Re:...but they still have all the disadvantages (Score 1) 461

Do you realize that the event and Chernobyl are impossible to happen to any reactor in France?

Rubbish. European plants are far, far safer than Chernobyl and the risks of a catastrophic meltdown are far, far less but impossible means that there is absolutely no chance of that happening under any circumstance. I think that highly unlikely: look at Fukushima. Rare events and human stupidity happen and all the safety systems in the world are not going to stop that. That being said I think that nuclear power is frankly safe enough and less risky than the alternative which is fossil fuelled power stations. So I would support France's strategy but don't kid yourself that it is zero risk. However the cost of cleaning up the rare, occasional nuclear accident may well be far less than the cost of dealing with accelerated climate change and given that any radiation release will likely be slow and is very easy to detect the risk to human life is minimal - it is the cost of cleanup that is expensive.

Comment Re:...but they still have all the disadvantages (Score 1) 461

True but the point is that if a reactor in France suffers a severe failure (which is far less likely than something like Chernobyl) parts of Germany may well get severely contaminated and not be inhabitable without a lot of expensive cleanup work. This is the disadvantage with fission-based nuclear power: there is a tiny, but non-zero risk of long term contamination of regions as well as a slight increase in the risk of cancer for those exposed.

You can argue, as I would, that this risk is very small and, I would go further, is far outweighed by the risk of releasing more carbon into the atmosphere. However is it not really possible to claim that when your next door neighbours are heavy users of nuclear power that you have escaped the risk of severe contamination because, in the unlikely event that their plants fail you will still get the radioactive fallout. Hence I do not see the sense in one European country shutting down nuclear power plants: either do it at the EU level or else you might as well benefit from nuclear power because you have the risks regardless.

Comment Re:Thanks for pointing out the "briefly" part. (Score 2) 461

If I can cut a ton of carbon emissions by switching to solar for a $40 subsidy or by adding insulation to an attic for $20 why chose the more expensive option?

If you could insulate a loft for $20 this would not be a discussion: at that price I'd pay for my neighbours as well! Unfortunately the real cost of insulating is far higher, try several thousand dollars and on most newish homes is standard - our loft is basically half full of polystyrene balls. Also the house construction in the US and Canada is typically wood which provides far less insulation than the cavity walls construction used in the UK and the cost of fixing that would be really prohibitive.

Comment ...but they still have all the disadvantages (Score 2) 461

Things like "not risking dying from radiation sickness"

For this to be true you also need all your neighbours to stop using nuclear power and unfortunately Germany is right next door to France which has a huge nuclear power generation capacity. Remember how far the radioactive fallout cloud from Chernobyl went? The result is that Germany now still faces all the disadvantages of nuclear power without receiving any of the advantages.

Comment Re:Gotta agree with it being illegal (Score 1) 404

You can't break a contract that has already been fulfilled. Money has changed hands, a physical good has changed hands. The contract is fulfilled.

Tell that to those convicted of trafficking in stolen goods. Contracts have to be legally fulfilled. What is being sold is not the physical ticket but the right to attend an event which can arguably be sold to an individual - instead of a ticket you could use photo-id and a list of names. The ticket is just a convenient, practical way to easily determine who has bought the right.

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