swansont

It applies to a traveling wave, but it's bent toward the normal if the optical density is higher. It minimizes the time spend in the denser medium while also reaching its target.

Yes! Succinctly put. A photon will also have an inherent uncertainty associated with it.

It's actually worse in this case, in my view, because the "it's happened before" argument is being dismissed in one instance (with regard to the rapid sea-level rise) as being a "ridiculous claim," while the other argument (temperatures historically stabilize, eventually and then go down) is being invoked, even though the the circumstances are different (namely, a whole bunch of CO2 that we've dumped into the atmosphere and ocean).

Indeed. It's humbling to think you know something and then find you can't explain it coherently, and have to admit that you don't really know.

I could use more heroine use, myself.

Take a rope, tie it to a pole or tree, etc., i.e. something solid. Shake it to make a standing wave. Now, let the tips of it hit the ground. What happens to the wavelength? Does the position of the antinode(s) shift much? (the answer should be essentially nothing/no) You're driving the wave in a medium at a certain frequency, and that dictates the wavelength. Not the interaction with the ground, even though you are coupling some energy to it. If the microwave were largely filled with chocolate, then your scenario would apply. That would be letting much of the standing wave hit the ground, rather than the tips.

Having something explained and actually learning it are two different things, in my view. Someone can explain X to me and have it make sense, but the true test is when I can explain it to someone else — to me, that's understanding, that's learning. Can I answer a question asked of me on the topic? It includes knowing when the principles do and don't apply to a given circumstance (i.e. knowing what assumptions are present in the model), and the many layers of 'infrastructure' that we have. I can explain laser cooling, but it's based on knowing photons have momentum, knowing about resonances, the Doppler shift, and several other concepts. These, in turn, are based on other concepts. Turtles all the way down. Plus, in doing this I have explained nothing, really, of how all of this actually happens. Even if I did, and explained a DIY experiment, could you troubleshoot it if something was set up incorrectly? That's what level of detail is missing in popularizations. When there were only two physicists in congress, they had a meet-n-greet to discuss this topic, basically telling the scientists that they need to do a better job of explaining why science is important (to me the admission that Congress needs this is really scary). But it was mostly a meeting with staffers. The person who told me this story was there with his former boss, a Nobel prize-winner, and he said it was clear that some of the staffers' jobs were to keep others from interrupting the conversation with the bigwigs. He was constantly being nudged away from his former boss.

It's hinted at in his original relativity paper. He comes up with the energy of a slowly accelerated electron. One only needs to look at v=0.

By definition.

No, they're not the same thing, but I'm struggling for a good description of why. I think a wave packet is, at best, a description of a photon under some circumstances. They aren't the same thing.

Right — if the universe is closed, then it curves in upon itself. The geodesic, or what we perceive as a straight line, is actually curved — Cartesian coordinates do not properly describe the geometry. I don't how you got to this conclusion.

This is the "bad continuity equation explanation" I alluded to earlier.

Alternately, you strike "pseudoscience" altogether. True pseudoscience is actually kind of rare around here, and I don't see posts about astrology or homeopathy getting much traction. Such threads, should they crop up, can simply be closed. The section becomes speculations, and is where any non-mainstream ideas get discussed.

It's good — anything to within 10% is for something like this — but it's not the error. Unfortunately this is often taught in physics class, or at least is not corrected. Error has to do with uncertainty concerning the experiment, not the difference between your answer and the accepted one. You might estimate that your measurement of the wavelength is to within ±0.5 cm. which would be ± 1.2e7 m/s, or 7.7% error. In that case, your answer and the accepted on agree to better than the error. Alternately, (and more deliciously) you could do the experiment many times and find the standard deviation of the measurements. You might get better results if you used a chopped up bar or smaller kisses (or just chocolate chips), spread out a little more. ——— I don't agree that you should use the speed of light in chocolate. The standing wave is in the air. The wave in the chocolate would not generally be a standing wave, it will be two traveling waves, and will not give you nodes and antinodes, since the return wave will be out of phase. And the amount of power in that wave will be small.

Yes. IMO, it's a veneer. A thin and polished cover, while the science beneath it is complex and deep.

They claimed a nuclear reaction, and it's neutrons that were missing, not neutrinos. The "establishment" was pushing the "dogma" that baryon number is conserved. If you're going to contradict well-established, experimentally verified science, you have to have solid evidence. They didn't.

I don't really know what the lay perceptions of physics are, other than that the ones portrayed here are often wrong. I don't think you can get anything but a superficial understanding of physics from a popularization — they skip over too many of the details. That cult of personality has an apparent influence in what physics people accept tells you it's not the value of science that driving it. In that regard it's no different than a persuasive con artist scamming you with a perpetual motion machine. The value of popularization is getting people interested in science, not in how much science they actually learn from that popularization.

m1 cancels, so its sign is irrelevant. But what if you change the sign of m2?

Yes. Bernoulli is a statement of conservation of energy. Newton is conservation of momentum. They both hold. If someone disagrees, ask which conservation law is being violated. I suspect the controversy arises because in some scenarios it's easier to see that one is true but the other is not at all obvious, e.g. the asymmetric wing usually uses Bernoulli but a symmetric wing uses angle-of-attack. And the standard explanations often get some details wrong (like how continuity is explained) and that is used as an argument to invalidate the whole concept. ——— regarding Coanda: A link from an aeronautical engineer. Read all of 18.4 http://www.av8n.com/how/htm/spins.html#sec-coanda "You may have heard stories saying that the Coanda effect explains how a wing works. Alas, these are just fairy tales. They are worse than useless." I don't have the background to vouch for it, though.

But the grid will likely be cheaper, and doesn't add weight to your car. I don't doubt that some cars might come with such an option. I just don't see that it solves a big problem. I'm just trying to point out where the real problems are. I think electric cars are the future, but it's a grid upgrade — production, preferably green, distribution and charging stations everywhere — that's needed most. That and an attitude recalibration for the long trips. Depending on the adoption schedule, this too will be solved over time. If such a car were available with a 100 km range, some people would buy them, and outfit their houses, if need be, to recharge the cars overnight. The impact to the grid would be minimal, and once critical mass has been achieved, the rest will happen as a matter of basic capitalism. But a battery's ability to be charged quickly is not what's preventing this from moving forward. I'll make a little less up, in a back-of-the-envelope calculation. http://www.eia.doe.gov/cneaf/electricity/epa/epates.html shows that US residential, commercial and industrial demand is roughly equal (to first order), with residential being the largest at ~37%. Presumably much of the industrial is dormant at night, so that's daytime demand. In the US the average household draws about 1 kW on average, so, 24 kWh per day. That's roughly the equivalent of 50 miles of driving. If you're recharging that, you've replaced more than the entire industrial load. Certainly residential and commercial go down at night, so the nighttime demand is still lower, but not by a lot. Interesting article. The numbers I've been using don't quite jibe with the recharging times and distances I'd seen and was using (factor of two or so discrepancies; I may have gotten older performance data), but the article doesn't mention how much current is being drawn or what the battery capacity is. edit: it's a Toyota Scion, which has a 35 kWh battery. The listed range is indeed a factor of two better than the numbers I was using (4 miles per kWh vs 2 I had seen a few places). It also means his special 240 V plug is delivering ~75 Amps if he can do a full charge in 2 hours.

Actually, it is a crude form of peer-review. Peer-review tells you about the shortcomings of your work, and things the reviewer think should be addressed. In my limited experience with it, I don't recall any "keep up the good work" comments. Critical review is going to be, well, critical. The key is how people respond to such criticism. The amount of personal insult that is perceived is generally proportional to the crankosity.

It's the scenario I described. An object on a scale on a planet, and a second observer moving with respect to the planet. Why do you denote transverse mass? Presumably it's different than longitudinal mass. It's no longer a scalar, per se, if you have to assign those tags to it.

A car covered in solar panels might get you a couple of kWh — insolation values are a few hundred watts/m^2 for Northern Europe and the US, and solar efficiencies are 25% or less. That's fine if you're only driving a few miles a day, but not for any longer-haul movement. And if you're going to plug it in anyway, it's not clear to me how much this gets you for the cost.

P&F is a really bad example to bring up. They didn't follow the standard route for presenting scientific material (skipped peer review) and it backfired on them, because their claims were overblown. Einstein, on the other hand, had a mathematical framework, based his work on established science and made testable predictions. If only the cranks would do things in a similar fashion.

I will reiterate: you've made two conflicting claims. Which one is wrong, or were both of them wrong?