Strange

This is an open area of research: http://en.wikipedia.org/wiki/Abiogenesis It is generally assumed to be some sort of "chemical evolution" where, at some point, particular sets of chemical reactions become self-sustaining and then were able to combine with other chemicals (e.g. those that could form a membrane to protct it from the environment). Most hypotheses require some specific external factors. For example, some models suggest that the structure of clay could have provided the right environment. One of the most intriguing ideas (to me) is that the availability of free protons (hydrogen ions) at deep see vents provide a source of energy that could have been exploited by the pre-life reactions. This is consistent with the biochemistry of all known cells and the DNA evidence. There is no reason the think that is the case.

Yes. But I am still not sure (because of your waffle) that you agree that one of them will determine that the two flashes happened at the same time, and the other will calculate that they happened at different times. Why do you need anything faster than light? We know the speed of light, so we can work out how long it takes light to travel a given distance. And the "speed of thought" (in so far as it means anything) is much, much slower than light. Slower than the speed of sound, even. Everything occurs before it is seen, because of the finite speed of light. It doesn't need any mythical "instantaneous viewing". This has nothing to do with relativity.

Yes, but relativity of simultaneity is NOT about the delay between something happening and when it is perceived. It is about the result when that delay is taken into account to work out when the events actually happened. That is what is different for the two observers.

No, that is purely a delay, due to the speed of sound, that causes them to hear things at different times (because they are at different distances). If they took the distance and the speed of sound into account, they would all agree on the time the shouts happened.

Do you agree that simultaneity is relative and that events that are simultaneous for one observer are not necessarily simultaneous for another? If not, perhaps you could explain what is wrong with the thought experiment as described (rather than your mangled version of it).

So you agree that simultaneity is relative and that events that are simultaneous for one observer are not necessarily simultaneous for another?

Maybe you should quote from the rules, then, rather than a dictionary. AT least, I assume it is a dictionary. In your usual sloppy way, you don't provide a reference.

But not understanding them, apparently. What? She is opposite him when the flashes occur. Not when he sees them. He sees them later, when they arrive at his location. They both arrive there at the same time. Therefore, in his frame of reference, they are simultaneous. But by then she has moved and is no longer opposite him. You said: But now you say: These statements are mutually contradictory. I watched it years ago the first time I tried to explain this very simple concept to a relativity denier. I just watched it again, just for you. It describes, as I remembered, exactly the same scenario and reaches exactly the same conclusions for exactly the same reasons. The only minor criticism I would make of the animation is that it is "not to scale". It exaggerates the differences in timing of events to make things clear. But apart from that I see nothing wrong, nor any differences, in the scenario described. EDIT: OK. There is one misleading sentence in the video "As the center of the car passes the observer on the platform, he sees two bolts of lightning strike the car - one on the front, and one on the rear." Arguably, that should not say, "sees". In everyday life, it would be reasonable (on these scales) to talk about seeing things at the same time as they happen. But because that is what is being analysed, it would have been better if they said the two flashes "occurred" at that moment (which is what the original says).

Then there is nothing more to say. I wouldn't know. I haven't watched it.

SHE ISN'T. Please, please, please read the description of the experiment. She is in the center, aligned with the guy on the platform, WHEN THE FLASHES OCCUR. Look: http://www.bartleby.com/173/9.html I should add, that I think his description is a bit wordy and confusing. I'm sure there are better ones.

No. Let's not. Let's just work through this one very simple example until you understand it. What is the point of adding more and more complexity to hide the underlying concept, if you can't even understand the simple version? You will only confuse yourself more. I assume this is a deliberate tactic to avoid actually admitting that relativity is correct. Why not focus on the problem (perhaps actually reading what it says). Why not explain at which point you disagree with the explanation - then it might be possible to address that specific misunderstanding. I have spent months trying to explain this very, very, very simple thought experiment to another crackpot who insisted on making up ever more complicated ways of refusing to understand it. I'm not sure why I am doing it again.

Maybe your confusion comes about from not clearly separating the two frames of reference. The setup explicitly says that the lightning strikes happened at the time that she and the centre of the train are aligned with the man on the platform, in his frame of reference. In his frame of reference the distance to A and to B is the same (because, by definition, he is half way between them). In his frame of reference the light from A and B reaches him at the same time (as defined in the problem) In his frame of reference the speed of light is the same for the light from A and the light from B. In his frame of reference he can therefore work out the time the two flashes occurred (using distance/speed; the distance and the speed is the same for both, they both occurred the same amount of time before he saw them) In his frame of reference the two flashes therefore occurred simultaneously. The whole point of the thought experiment is to answer the question: "does this mean that they happened at the same time in her frame of reference?" In her frame of reference the distance to A and to B is the same (because she is half way from the front and back of the train). In her frame of reference the light from A reaches her before the light from B. Because, as you rightly say, she is moving towards the photon/wavefront from A and away from the photon/wavefront from B. In her frame of reference the speed of light is the same for the light from A and the light from B. In her frame of reference she can therefore work out the time the two flashes occurred (using distance/speed; the distance and the speed is the same for both, they each occurred the same amount of time before she saw them) In her frame of reference the flash from therefore also A occurred before the one from B (because they travelled the same distance at the same speed but she saw the one from A first).

As an engineer, I find the large number of anti-relativity cranks who are engineers to be slightly depressing. But, yes, being a successful professional scientist does not make you immune from this. There was the recent case of Erik Andrulis, a well-respected biochemist who has published a lot of good work in his field, who managed to get a meaningless "theory of everything" paper published.

Indeed. I suspect that the sort of people who make the sort of statement I was responding to, have no idea where the real challenges are. But instead they object to the fact that even well-understood areas of science are not easy for them to understand.

Because (read the description) she is in the middle of train, half way between A & B. Perhaps the other bit you don't get, is that from her perspective the flashes originated from the front and back of the train. But it is hard to follow what objections you are inventing.

Sorry - typo! - I was trying to contrast fusion and fission - I'll fix my post. Dang. Cant edit it any more. What it should have said was: Fission occurs in large atoms, which means they form solids. So materials like uranium and plutonium. This means they are relatively easy to work with and contain. On the other hand, fusion works with light elements (typically hydrogen) which is a gas. ...

No. All you get is the sum of the two forces. I assume you mean things like the magnetic fields, light pressure from the sun, etc. They are not taken into account because they are so small they have no measurable effect.

It will only go there when there is some objective evidence for anything related to the "realm of the spirit". All, of course, predicted by theory and measured in practice. (Unlike your woo.) Ain't science cool.

It is clear enough if you understand it. Nope. Not even one. I can't think of an example. Can you? But that's the good thing about science! That is what makes it so exciting. There is always more to learn. I think it is only the inattentive or stupid who think that physics is "is not clear, is full of paradoxes, of mutually exclusive theories".

Nope. Because ... it's a science forum.

Er ... science forum. Why come to a science forum and talk about things that are not supported by science? And why isn't science "there" yet? It is not as if it hasn't been studied (it has). Perhaps you expect science to lower its standards in order to accpet your beliefs?

I see you haven't changed your views, even after your generalizations and absolute assumptions are shown to be wrong.

I'm betting you can't cite even one scientific paper which demonstrates that there is any basis to astrology. (I'm sure you can dig up any number of books, videos, poems and pops songs. But, again, this is a science forum.) Citation needed. Provide some objective evidence and we will consider it. You need to get out more. That's another myth, you know. It has nothing to do with "knowing facts". It is about the scientific method to testing those "facts".

Pseudoscience. Ideas that are dressed up with some of the terminology of science but do not use any of the methodology. If you learn from a crackpot, you will be learning nonsense. Or at least, non-science. It is nothing to do with "the state's academia" (whatever that means) or who you should learn from. It is about evidence-based methods for testing knowledge, backed up by critical thinking skills.

That is all very interesting but it has absolutely nothing to do with science. Or even pseudoscience (which is what crackpottery is).