Eise

One simple way to see it: a^3 = (a^4)/a a^2 = (a^3)/a a^1 = (a^2)/a = a a^0 = (a^1)/a = a/a = 1 Does that make sense?

The second postulate is that the speed of light is the same for all observers. (And not that c is the limiting speed of material objects.) As said, 'my light cone' was also of Joigus. AFAIU Joigus' intention with the latest, was to show that your remarks about light cones were much too vague (as usual): they also fit these funny space-time diagrams. So you are just reinterpreting a piece of science history. I am sure Ole Rømer hypothesized that the anomaly in the orbital times of Jupiter moons was caused by a signal delay, i.e. that the light signals do have some measurable speed. So this is no argument at all. The units, yes. But light has a fixed speed in vacuum, independent on which units we use, be it inches, cm, meters, seconds, minutes, hours. Yep, this anti-correlation is given, as we are talking about entangled particles. What would entangled particles be without correlation? So the correlation 'an sich' is not a hidden variable at all. The Bell experiments prove that the correlation is stronger than can understood classically. And you are arguing classically all the time, so no wonder you keep hammering on the idea that there should be a signal, interaction or whatever. Where did Markus say that the direction of the spins are fixed? Nope. They even had to delay the entangled photon, so that the classical signal would be at the other side first. The correlation between the entangled photons is instantly, yes, but that is just an attribute of any form of correlation, like the left and right shoe example. quantum teleportation as a whole is not instantly.

Eh? Joigus did it: It seems you really do not understand EM either. Just take the historical lesson: Maxwell discovered the laws of EM, based on the experimental results of Faraday, and his ideas of electric and magnetic fields. Maxwell discovered that his equations implied that EM waves should be possible, because he could derive a wave equation from them. According to plain old classical wave mechanics, he showed that the speed of the waves should be sqrt(1/(mu_naught * epsilon_naught)). As this fitted very well to the known speed of light, he concluded that light is an EM wave. And now you say that c is not so much light speed????? Oh my. I also want to mention, that you obviously simply do not understand, or evade all explanations given. On one side, you said you fully agreed with Markus' first explanation (but where for me it was obvious that this could not be, he clearly explained why you were wrong). But then, Markus showed you made the same errors all over again. So you did not understand one word of what he was arguing. Please, learn real physics.

And I explained that nobody was even saying this. So you were beating a dead horse. So let's try to explain it once again. As a starting point we take a Bell experiment, that closes the communication loophole. This means: the measurements cannot influence each other with a light signal, or any slower signal the decision which spin direction will be measured is taken after the particles left the entanglement source So there can't be any causal connection between measurement device A, B, and the entanglement source. Said otherwise, no communication is possible between these 3 components. To make the example as simple as possible we also assume that detectors and entanglement source do not move relative to each other, and the entanglement source is exactly in the middle, so the measurements are exactly at the same time in the rest frame of the experiment. Are you with me so far? Maybe Joigus' drawing helps: Just take Alice and Bob as other names for the detectors. So now we ask ourselves what Carla and Daniel will see. Well, it is in the drawing: in Carla's frame of reference the measurement at Bob's side is first, for Daniel's FoR it was Alice's side. It is just a question of perspective, not of changing anything with the experiment of course. Got that too? Now according SR observers can disagree on the timely order of events, when these events are space-like separated. But that is exactly what the closing of the communication loophole means. But SR also states that Carla and Daniel should at least agree on the physical process. But they don't: according to Carla, Bob's measurement determined the outcome of Alice's according to Daniel, Alice's measurement determined the outcome of Bob's But these cannot both be true. So the conclusion is that there is no 'determination relation' between the measurements. So no signal, FTL or not. For Alice and Bob of course nothing changes. In their FoR the measurements are simultaneous, just as before. So Carla or Daniel have no influence at all on the experiment. But they should agree at least on the physics.

Seems you have wax in your ears: Nobody claims that observers that are in other inertial frames of reference affect the experiment. There you are right, for one time. To understand entanglement, one must understand QM. But as said, SR is a 'filter' for possible explanations. If an explanation is in conflict with SR, then it is wrong. Yes, that is what I said. (No, it wasn't, but I let that be.) Then did you read it well? Or didn't you understand it (again)?

Now it would be interesting to know if you agree with Markus' descriptions. 'Unrelated'? You simply do not see what the relation is. One could call SR a 'meta-theory': it describes how space and time transform when seen by different inertial observers. As we all observe physical phenomena in space and time, all fundamental laws of physics must pass the test if they are Lorentz invariant. If they are not, then they are not correct. An FTL signal does not pass the test, so an entanglement explanation that contains an FTL signal cannot work. That is the whole argument in a nutshell. Even QM must 'obey' special relativity, which it does, as QFT.

And of course a +1 for Markus. At least I understand it a little more clearly now.

That goes back to the old example where lightning strikes both ends a train simultaneously on both ends relative to an observer in the center. Oh my. In the entanglement situation we are discussing that different inertial observers, in your interpretation where there is a FTL signal, must see one signal (between the measurements) going into opposite directions, but taking the same trajectory. And now you come with an example with two signals, taking two different trajectories, one of the front of the train to the middle, the other from rear to the middle. And this has to do nothing with SR. SR is not about observers being at different locations. That can be handled just as well with Newtonian mechanics. Just take the signal velocity in account, and you are done. SR however is about the different observations by observers in different inertial frames of reference, i.e. observers that move (fast) relatively to each other. Do you know the difference between spacial distant events, and space-like separated events in SR at all? I thought so. Case closed. Ah. It only violates one of the two groundstones* of SR, without which SR would be thoroughly false. At the same time SR is essential to our understanding of QFT, it is the basis even of our classical understanding of electro-magnetism, it is practically essential for GPS and particle accelerators, it explains the colour of gold and the liquidness of mercury, etc, but yeah, the invariance of light speed is just a provisional conjecture. You have no idea how SR is one of the roots of our understanding of the physical world. Every fundamental law of nature must pass the criterion that it is Lorentz invariant, i.e. does not lead to inconsistencies when we apply SR. * BTW the second postulate is not that nothing can go faster than light, it says that the speed of light is invariant. That no material object can reach the speed of light is a conclusion of SR. He, 22 already! Do not eat too much popcorn...

Nope. You said: For which I wanted an explanation. Then you said: And then I asked an example of information transfer, or a signal, that works without a transfer of energy and/or matter. So maybe I was a bit confusing, but I want two examples: One of "Different observers seeing signals going into different directions" and how this is "a well understood phenomenon of SR". Information transfer or signal, without any energy or matter involved. And both not using entanglement, because that would mean you are using your conclusion about entanglement as argument, with other words you would "beg the question". And I am still waiting for a reaction on my posting:

Nope. An observer with a constant velocity compared to a defined inertial frame will observe distances, durations etc differently from an observer in that defined inertial frame. What is true is that when we have an inertial frame of reference, and an observer is moving with constant velocity relative to that inertial frame, then that observer is also in an inertial frame. But it is another one.

So you mean the entanglement source and the detectors are in same inertial reference frame, in other words, they are at rest relative to each other? Then say so. Next step: is this a preferred frame of reference? A preferred frame of reference in this context would mean that only in this frame correct conclusions about what physically is happening can be drawn. Next step: according to SR there are no preferred inertial frames of reference. Still, all observers, whatever their speed and direction, agree on the physics about what is going on. (However they can differ on distances, durations, timely order of events, simultaneity etc.) That is against 1., so 1. does not apply: the inertial frame of the experiment is not a preferred frame of reference. Next step: if there is a physical signal from one measurement to the other, all inertial observers should agree on this signal, especially its direction. Next step: for some observers Alice's measurement was first (e.g. Daniel in Joigus' drawing), for others Bob's measurement was first (Carla). Next step: Daniel and Carla do not agree on the direction of a hypothesised signal. But as they, according to SR, should agree on the physics of the situation (in this case which measurement determines the other), there can be no signal. As you see, there is no influence whatever from the different observers. Italics: Nope. Every observer observes the measurements, but they do not agree with each other which was first. So there is no objective first. Just to be sure: that is only true when the measurements are space-like separated, in the SR meaning of that concept. Not just space separated. Which you are using in your next argument: Oh my! In SR we talk about inertial frames of reference, not about the position of observers in space! It is 'easy-peasy' for Alice, if she knows the distance to Bob's detector, to conclude that his measurement was at the same time as her measurement. If detectors and entanglement source are in the same inertial frame of reference, Alice and Bob can agree on which measurement was first (or if they were simultaneous). Obfuscation from your side again: you have changed the meaning of 'reference frame'. Or you have a total misunderstanding of SR. Or both. Nope. I say that for space-like separated events there is no objective order of events. And just observing does not change anything. Do you really think we are saying that Carla and Daniel change the 'objective' order events, and that in different directions?

Again use of vague concepts. What does 'grounded' mean here? That the experiment happens to be done in an inertial frame? OK, obviously you need reading glasses. So in a large font, specially for you: Nobody claims that observers that are in other inertial frames of reference affect the experiment. The rest of your argument is BS. Observers in other inertial frames, like in Joigus' drawing, Carla and Daniel, see the space-like separated measurements, assuming they were simultaneous in the frame of reference of the experiment, in opposite timely order. Still they must agree on the physical interpretation of the measurements. A signal from one measurement to the other cannot fulfill this condition. And, BTW, Alice and Bob are in the same inertial frame as the experiment. So what was the difference? I said, an example without entanglement. Oh man... It is so simple. According to SR there is no preferred inertial frame of reference. But you take the FoR of the experiment as such. I think that is also the reason why you keep sticking to this stupid idea that we think that other observers somehow change the order of events.

And, oh, by the way, I am still waiting for an example:

So what is the difference between the entanglement experiment and the Alice and Bob scenario? What? SR is the theory of how observers in different inertial frames of reference see physical events. It is the theory about how events are seen across different reference frames. How often must I repeat this? No order of events is 'changed'. Observers in different inertial frames of reference just see them in different timely order, when events are space-like separated. So this is blatantly false: Again: the essential improvement of Aspect's experiment was that the measurements were space-like separated. And when the measurements are, then there will be inertial frames in which the timely order of the measurements is in one direction, and others where it is in the other direction. And that is exactly what I am saying. However, you use the inertial frame of reference of the experiment as a preferred frame of reference. Which is prohibited by SR, exactly as you say.

So your answer on my question of giving an example of a signal that does not imply transfer of energy is "No, I do not have such an example". Try again. And do not forget: no begging the question. Another example as entanglement. Sigh. I nowhere said that results are changed because of 'outside observations' (I assume you mean 'observations by observers that move relative to the experiment'. Why are you so vague again and again?). I am saying, trying other words, there is no universally agreed timely order of the space-like separated measurements. The inertial frame of the experiment has no 'special authority': that would mean it would be a preferred inertial frame of reference, which is against SR. So different observers do not agree upon which measurement was first, and therefore about the direction of a signal.

The measurements do not have to be 'at the same femto second' in the rest frame of the experiment. To be space-like separated is enough. As in Aspect's 'real world' experiment. Really? A real signal, i.e. transferring information (and therefore at least a minimum amount of energy)? Or will you beg the question, and will give entanglement as example? So, please, give an example of such a signal, but not concerning entanglement. Simultaneous according which observer? Simultaneity is not even agreed upon by different observers for time-like separated events. Only the timely order is.

No, I noticed earlier, but I always give people the benefit of the doubt. Maybe bangstrom has some problems understanding texts, maybe he doesn't know SR, etc... But I already called him a troll much earlier: Page 14 .

It is obvious what I mean: again you are obfuscating the discussion. Of course I mean it in the context of SR: all inertial reference frames are equally valid; none is privileged, not even the inertial frame where entanglement source and measuring devices are at rest. So if we have two events, e.g. two measurements, that are space-like separated, there is no fixed timely order. You are moving the goal posts. Yes, it is easy, just setup the experiment so that the measurements are time-like separated. But that was not what we are talking about. You are evading the point we are making. As you know, we say there is no message. And one of the ways of seeing that is that when the two measurements are space-like separated, the timely order is different for different observers. Signals have a direction. But a signal going into one direction for one observer, but in another direction for another observer makes no sense physically.

Which is not relevant at all for the point we are making with our references to SR. You could just as well have said "the earth is a sphere": it is true, but not relevant when discussing space-like separated measurements. Again: the improvement of Aspect's experiments compared to Clauser's, was that the measurements were space-like separated, i.e. even a light signal would not be fast enough to 'tell' the other measurement what it should be. Yes, you did: Here you take the inertial frame of the entanglement source and the measurement devices as a preferred frame. There is no change in order of events. With space-like separated events there is no objective order of events. For one observer measurement 1 might be first, for another measurement 2. Nothing changes. It is only a change of perspective. It's OK, I didn't criticise your anthropomorphic expression. I even went with it, and I do it here again: no, there is no way that on basis of a measurement one can know if the other was already measured or not. If you think you can, then show us how. But with space-like separated events, mind you, in the SR meaning of the word, not with 'space distance'. I nowhere said such a thing. If you think I did, cite the relevant text passage.

So that means your argument is not relevant. That particles at different locations have a space distance is a tautology. That two measurements are space-like separated in a space-time diagram is not. This is just one example of you confusing, or better, obfuscating, the discussion again and again. (Calling' non-locality' 'not realist' is another one.) As repeatedly said, the inertial frame of the entanglement source and the measurement devices is not a privileged frame. There is no 'objective now', and no absolute timely order for space-like separated events, so no objective first. There is no way, even for the measurements themselves, to 'know' if its entangled partner has been measured. There is no flipping of the wave function before it is measured: there are only measurements. It takes so long because you do not see the relevance of it. You only show again and again that you do not understand SR, and therefore you do not understand the relevance.

Here you show where you do not understand space-time diagrams. If you would draw a simple space diagram, yes, then there is a space distance between particles at different locations. But that is not the same as a space-like separation between 2 events in a space-time diagram! One could call a space-time diagram also a causality diagram. Events that are space-like separated cannot have a causal connection. Events that are time-like separated can have causal relationships. And because of the 'law of conservation of causality', i.e. every observer agrees what event was the cause, and what event is the effect, every observer agrees about the timely order of events. And as there is no possible causal connection between space-like separated events, there is no problem that different observers see them in a different timely order. And this is the crux of Aspect's experiment, where it improved on Clauser's: Aspect set up the experiment in such a way that the measurements could not even influence each other with the speed of light. In other words, they were space-like separated, i.e. outside each other's light cones. This (italics) is definitely false: Nobody here defended that there are observers that see time-like separated events in a different timely order. Your first sentence is correct, except that it is not relevant precisely because the essential improvement of Aspect was that the measurements were space-like separated. Recall, the measurements, i.e. events, were space-like separated. Not with Clauser's experiment. There of course there was a spatial distance between the measurement devices, but the measurements were not space-like separated, in the sense of SR. All this confusion arises because you are so sloppy with what a space-time diagram depicts, namely events, not physical objects. A physical object A in a space-time diagram is a chain of events, A being at x1 at t1, at x2 at t2, etc. Drawn all infinitesimal positions and times, the physical object A will show as a world-line, never as an individual point. Again, your use of the concepts in your arguments are so vague, that they are, well, not even wrong. They miss the matter under discussion completely.

This shows you do not even understand what SR is about. The 'objects' in a space-time diagram are events, not physical objects of any kind, so not particles either. Important to note is that the measurements (that are events) both lie in (e.g. when using electrons) or on (when using photons) the future light cone of the event in which the entangled particles were created. Of course observers have no effect on the timing. But when the measurements (events!) are space-like separated, there will be observers who see Alice's measurement first, and others that see Bob's measurement first. So that would mean that the first observer must, according to you, send a FTL signal to Bob, but for another observer Bob must send a signal to Alice. But under relativity, all observers agree on what physically is happening. A signal going into one direction for one observer, and into the other direction for another observer, cannot be a physical signal. A none-physical signal is no signal at all. And this has nothing to do with: Observers can perfectly calculate the delay due to their distance of the measurements. And they still will observe that they see the measurements in a different timely order. Space-like separated events do not have a defined timely order, it depends on the observer. And don't forget: the inertial frame in which the entanglement source, and the measurement devices of Alice and Bob are standing still, is not a privileged frame. You really do not understand SR, and the relevance of it for understanding what the true impact of entanglement is.

I find it a terrible error that we have invested, and are still investing, so much money in nuclear technology, just to keep up the energy that our society is wasting everywhere. If we had used all that money in technologies that save energy on one side, and develop durable energy sources, we would have no problems now. We are stuck with a technology that works, but I still don't know of any country that has a definite solution for nuclear waste of nuclear fission plants, and how to go on when we are running out of U-235; and a technology that will be successful 50 years in the future, and will always be that way.Yes, I am very pessimistic that we will ever have useful nuclear fusion power plants.

Seems just an old fashioned neon bulb. If you want to be careful, and have some nice power supplies, I would slowly turn up the AC or DC to 220 Volt. Otherwise turn it into the correct E27 fitting, and connect it to the power grid. Best with a switch of course, and safety glasses on. Here an example, DC one direction, DC other direction, and AC:

Oh, I nearly always see steel constructions in thunder clouds ... OK, without joking, there is a nice subtle difference in Kevin's thunderstorm, and real-life thunderstorms. With Kevin, all the droplets fall downwards. So my guess is that this construction is needed, because otherwise the influence can not be self-amplifying. In real thunderclouds of course we have up- and down-streams, making steel constructions unnecessary.