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Comment Amplitude not Height (Score 5, Informative) 61

I think you mean that their amplitude can be as much as 500m. For a start these are not surface waves so they do not raise the water surface. Additionally, although the article does not really specify it, I would expect that they are actually far more longitudinal than transverse in nature and so the displacement will be almost entirely in the same direction of the wave motion i.e. horizontal. Fluids generally tend to be very poor transmitters of transverse waves because they cannot support a shear stress.

Comment Re:Hmmm ... (Score 1) 312

But the question (for which I don't pose an answer) is "do we accept there are valid limitations on free speech, and if so what defines that?"

Really what we mean by free speech is that we should be free to communicate any ideas or feelings we have without restriction no matter what they are. Where we should draw the line is with deliberate lies which will likely result in physical harm or loss of property e.g. shouting fire in a crowded theatre when you know that there is no fire, lying about a financial scheme to persuade people to invest etc. Here though it is not the speech which is illegal but rather the intent of the person speaking.

Comment Re:One Criterion Missing (Score 1) 416

New science is not always required if something odd is noticed.

True but this is a little different from your example. There is no fundamental law of physics saying that you cannot build an instrument large enough to observe distant planets. In the absence of such a restriction building that instrument is down to human ingenuity. However there is a fundamental law of physics which says that momentum is conserved.

As a result this force is either due to some interaction with the surroundings that the experiment has forgotten to account for or is due to new physics in the form of new particles/interactions or violation of conservation of momentum - which is an extremely fundamental law of physics. There really are no "loopholes" to squeeze through.

My personal feeling is that it will turn out to be some effect which they forgot to account for although I cannot help but hope that it turns out to be something far more interesting...which is why it is so easy to fool ourselves when doing experiments.

Comment A lot more than one (Score 1) 532

Yet I bet nearly every one of us has dealt with at least one error or oversight that benefits the company

I lived for several years in the US just over a decade ago when MCI was a long distance phone company. They made so many mistakes that it became a joke: there was at least one error every 3 months and it was always in their favour. Even the one time they accidentally credited my bill with someone else's far larger payment they tried to charge me a late payment fee when they corrected it several months later despite acknowledging that I had informed them of the mistake at the time it occurred!

If you contrast this with Canada I don't think I have ever had an error on a bill since I moved here 12 years ago. Even in the UK, where I was moving around more frequently, the only time I had trouble was with either the setup or termination of services which was more understandable. As a result it is hard to believe that the massive rate of mistakes I observed in the US (and not just MCI, although they were by far the worst) is entirely due to incompetence and it seems far, far more likely that it is a deliberate policy of some companies to overcharge and then hope that you cannot be bothered to complain.

Comment Need more data (Score 5, Insightful) 249

The only evidence uncovered is that the PD has a robust system for reporting and investigating claims.

That's not quite true - the evidence suggests only that they have a robust system for reporting and recording claims. I've not seen any evidence to suggest that they robustly investigate them and the OP claims that there is evidence of them using unnecessary force and racist language without repercussion which, if substantiated, would be clear evidence of very poor investigation.

I completely agree that having a large fraction of claims refused is not evidence that the system is not working. It does suggest that the system should be investigated to understand why there are such a lot of dismissed complaints because either cops are having to endure a lot of frivolous discipline cases or they are getting away with serious misconduct. Either possibility is bad but the statistics provided do not distinguish between the two cases.

Comment Re:One Criterion Missing (Score 5, Informative) 416

No. These tests prove that the device is real, and that it produces force.

Actually that is NOT what these tests show. They show that someone has done an experiment which, using their apparatus, returns readings consistent with a micro-newton force. What the experiment has NOT shown is that this is due to some new, as yet unexplained, physics.

There are a myriad of other, far more mundane, possibilities to generate such results before anyone will seriously start believing in new physics as an explanation. For example did they account for the radiation emitted bouncing back and forth between the apparatus and the vacuum chamber walls?

After the results have been confirmed independently and all the possibilities people can come up with disproven then you have an interesting result which is unexplained. At this point there are still two possibilities: either new physics OR an effect so subtle that nobody has thought of it. The only way to prove new physics is therefore to come up with a theoretical explanation which allows testing.

Whether or not you agree with this this is how science works: there are simply too many ways that a precision experiment like this can be fooled and history is littered with examples of this happening e.g. faster than light neutrinos, gravitational waves in the cosmic microwave background, cold fusion etc. The results have to be confirmed and stand several years of scrutiny before people will start to believe that they are interesting. Even when that happens to get people convinced that there is new physics here you need a model for that new physics that makes predictions which can be confirmed.

Comment One Criterion Missing (Score 4, Insightful) 416

Actually this is the one criterion missing from the list of "what would it take to convince you that it is real": a viable theory as to how the drive works which makes a prediction that can be tested by another experiment. If this is a real effect then we need a theoretical framework which can be used to explain and predict the size of the effect under different conditions which can then be tested.

This is how the solar neutrino problem was solved. For decades experiments measuring the flux of solar neutrinos had come up short by a factor of 1/3 to 1/2 of the expected value. Initially people thought the experiments were somehow wrong, then focus switched to the solar models predicting the flux but these were confirmed as correct so ultimately nobody had a clue as to why there was discrepancy. People were split between inaccurate experiments, inaccurate prediction or new physics. The problem was solved only when the model which theorists had proposed as a possible solution - that neutrinos changed their flavour as they move through space - was tested by the SNO experiment which measured both the total neutrino flux and the electron neutrino flux separately.

You need both theory and experiment to agree to get understanding and without that clear understanding I would not expect the 'warp drive' effect to be resolved. No matter how much you repeat and verify the experiment there will always be questions raised about some effect which is not accounted for (assuming the effect remains so small). After a few decades you might get to the point where people will admit that the effect is not understood but even then many will ascribe it to some subtle experimental effect rather than new physics. The only way you will change minds is by having a new theory whose predictions are verified by further experiments.

Comment Renewable and Nuclear Power (Score 4, Insightful) 280

I have the same gripe with calling Teslas "zero emission vehicles". They are not.

True, but unlike petrol driven cars they could be. Both renewable and nuclear power power are zero carbon methods of generating power and while renewable has issues with cost, limited locations and variability if it were supplemented by nuclear we could significantly reduce greenhouse gas emissions. In fact if you charge your Tesla in France then 75% of that power comes from nuclear so you might not be zero emission but you will be getting close.

Comment Who decides what is "super" (Score 2) 352

Those roles can't be done by some national "super teacher."

The other problem is who decides the criteria for being "super"? Different people find different teachers effective. For example I know that Feynman was regarded by most as a "super teacher" but I hated his books and found his explanations needlessly complicated and far more confusing than most other textbooks. In short I found him a terrible teacher. I realize I'm in the minority with that but the point is that not everyone will agree on who a super teacher is because different people learn differently. This is why you need to learn from a variety of teachers and not just the most popular.

Comment Deccan Traps (Score 2) 152

A super volcano could be extinction event if it is big enough.

Not unless it is a lot bigger. The one that occurred around the time of the extinction of the Dinosaurs gave rise to the Deccan Traps.

To put the scale of this extinction-level eruption in context the article mentions that the new, larger chamber under Yellowstone contains enough magma to fill the Grand Canyon which according to here is 4,170 cubic kilometres. The Deccan trap eruptions produced 512,000 cubic kilometres over 30k years. A Yellowstone eruption would certainly cause a lot of devastation over a large area of North America but its peanuts compared to an extinction level event.

Comment Cut the rhetoric, look at the evidence (Score 0) 341

Contrary to your argument, those who receive the chickenpox vaccine seem to have proven to have a lower risk of shingles [cdc.gov] (scroll to "Risk Factors").

...and yet the vaccine prevents those people who already had Chicken Pox as a child being re-exposed to it the virus later in life which has been shown to prevent shingles in adults.

Now I could accuse you of spreading lies and deceit but really that would be behaving exactly like the anti-vaxxers: adopting a preconceived notion, ignoring all scientific evidence to the contrary and getting mad at anyone who disagrees. So how about we adopt a more scientific stance which is that for the specific case of the Chicken Pox vaccine there is no clear evidence that it is a net benefit to individuals or society over just catching the disease as a child and recovering? The risk of the vaccine is not measurably less than the risk of the disease and there are clear questions about the net affect of susceptibility of adults to shingles: it might be good or it might be bad but we really don't have a clue either way.

My position is that if there is no clear evidence for any benefit from a medical procedure then you don't do it. If that changes with more studies and they can show that there is a clear benefit then great I'd be 100% behind it. In the meantime I would argue that it is unethical to coerce people into undergoing a medical procedure for which there is no evidence of a net benefit to them or to society. Worse, because in this one specific case, the evidence is lacking you give the anti-vaxxers ammunition which they can use to shoot at the cases where the vaccine is incredibly beneficial and absolutely should be taken by everyone.

Comment Re:Agreed but there is a point (Score 1) 341

You speak as though getting chickenpox will prevent shingles which it won't

Correct - once you have the virus you never lose it and shingles can emerge if something compromises your immune system. However if you have the vaccine and then the immunity wears off and you are exposed to the virus again then you can get shingles even without a compromised immune system.

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