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  1. 8 points
    So if I change the charge of one plate, somebody can measure an instantaneous change at the other plate. Wouldn't that be a violation of special relativity? @Menan You show that you do not understand entanglement. Let's go one step at a time. First a classical example. I have a bag of balls, they are all red or green. Without looking I pick two balls, and I put them in separate boxes. I keep one, and send the other far away. Then I open my box, and see it is a green ball. What can I conclude about the colour of the ball in the remote box? Right, nothing. And why? Because there was nothing special with my picks. It could have been two reds, two greens, or one red and green. Now I pick, looking of course, one red and one green, and put them in two separate boxes. So what I did here is 'entangle' the balls. Now I shuffle the two boxes, so that I do not know which one is which. If I open one, and see that it is red, I immediately know that the ball in the other box is green. And of course, this is independent on the distance. If I send the second box lightyears away, and only then open my box, I still know immediately what some alien sees when he opens his box. I know it because the observations are correlated. And the correlation already happened at the moment of my picks. That is the moment of entanglement. It is not when the boxes are opened. Now in quantum physics, there are processes where two particles pop out, which have e.g in one aspect always opposite values. Say the direction of spin. So if I measure the spin e.g. in a vertical direction, say it is 'up', then I immediately know that the other one will measure spin 'down', when also measured in the vertical direction. But as with the balls, the 'moment of entanglement' is when these particles popped into existence. But in quantum physics a few things are different: first, it is impossible to say which particle has which spin without measuring (it is as if I created the green and red balls, including their boxes, without knowing which ball is in which box). But as the two particles are entangled, if I measure both, the measurements will always be correlated. And there is nothing special with correlation: if I send one particle far away, and then measure my particle in the vertical direction, and the alien measures his particle in the same direction, I will always know what he measures: the opposite of my measurement. The 'spooky' aspect comes in when we do not know from each other in which direction we measure the spin. It can be vertical, horizontal, 30o, 45o, 55.3977o. What we find is that the correlation is stronger than one would expect if we would assume that the particles already had a definite spin from the beginning. But it still is correlation, not causation. As with the red and green balls, there is no direct causal relationship between my and the alien's observation. The causal relationship goes back to the moment of 'entanglement'. Everything afterwards is just correlation, and therefore cannot be used to transfer information. And because there is no causal relationship between my measurement of the spin of my particle, and the alien's measurement, I cannot use entanglement for sending information. And all this is very well understood by all quantum physicists, and is no secret at all.
  2. 7 points
    SR does not claim that such an observer will always see the Earth clock run slow, if by see, you mean what his eyes or instruments directly record. In this usage of see, he will see it run at a rate of T = To ((1-v/c))(1+v/c))1/2 where v is positive if Earth and the Observer are receding from each other and negative if they are approaching each other. A factor contributing to this observation is the the distance and thus the propagation time for signals is constantly changing, getting longer when receding and getting shorter when approaching. This factor works out to be c/(c+v) When you factor this out of the first equation you are left with the time dilation equation. This means that there are two things to consider: what you see happening to the Earth clock, and what is happening to the Earth clock. So while while receding from the Earth, the observer will see the the 1000 Hz signal as being 500 hz and the Earth clock as ticking 1/2 as fast as his own,. Taking into account the effect of the increasing distance, he will determine that the Earth clock is ticking 0.8 as fast as his own. He will meet up with the object when his own clock reads 1.01.2022 (as the distance between Earth will be only 1.2 ly as measured by him and this is how long it takes to traverse this distance at 0.6c.) He will see the Earth clock reading 1.01.2021, but determine that it is 8.07.2021 on the Earth at that moment. Now at first, you might be tempted to think " But wait, if he sees 1.01.2021 on the Earth clock, and the Earth is, according to him, 1.2 ly away, wouldn't that mean that it should be 3.15.2022 on the Earth by his reckoning?" This is not the case. The light he is seeing at that moment left Earth at a time when the distance between them was less than 1.2 ly, so the time it took the light he is seeing took less than 1.2 years to reach him from the Earth. Now he accelerates in order to come start the trip back towards Earth. We will assume a minimal acceleration period. Now this is the part where people tend to get tripped up. After he is done and is now approaching the Earth and not receding, we will assume that he still reads 1.01.2021 on the Earth clock by visual means. However, he will no longer conclude from this that it is 8.07.2021 on the Earth. Instead he will conclude that it is 6.05.23. During the return trip he will see a frequency of 2000 hz from the signal and the Earth clock tick twice as fast as his own. But again, taking into account the decreasing distance effect, he will conclude that the Earth clock is ticking at a rate 0.8 as fast as his own. Thus he will see the Earth clock tick from 1.01.2021 to 1.01.2025, but conclude that it ticked from 6.05.23 to 1.01.2025 during his return leg. (see will see it tick off 4 years, but conclude that it ticked off 1.6 years. Again, it all come back to what happens during that acceleration period. As far as anyone at rest with respect to the Earth is concerned, nothing special beyond the standard SR effects take place. But for the observer actually undergoing the acceleration, things aren't this simple. For him, the rate at which clocks run depend on which direction they are from him relative to the acceleration he is undergoing and the distance from him in that direction. Clocks in the direction of the acceleration run fast, and those in the opposite direction run slow (beyond what he sees. This even effects clocks that share his acceleration. A clock in the nose of the Ship will run fast and one in the tail will run slow. ( in this case, since there is no changing distance between himself and the clocks, what he sees, will be in perfect agreement with what is happening to the clocks. While this may seem to be at odds with common sense, it is how a Relativistic universe works. A problem with your questions is that they only deal with particular points of the whole scenario without taking in the whole picture. It like comparing two men walking and only considering where they end up. Below we have the paths of two men, Red and Blue, over the same interval. If you just look at where they end up, you would conclude that Blue walked a shorter distance because he ends up closer to the starting point than Red does. But when you consider the whole interval, it is clear that Blue walked a further distance. The same thing is true with SR, if you only consider the end results, you are missing what is really going on.
  3. 6 points
    Right, he is saying that the speed of light in both directions is the same with respect to any inertial frame as measured from that frame. So in the following example we have two observers. One standing along the tracks and the other traveling along the tracks in a railway car. Two flashes are emitted from two points along the tracks that are equal distance from the track observer. the light from these flashes arrive at the midpoint observer at the same moment as the railway observer is passing him. Thus both observers detect the light from the flashes at the same time. Like this: For the midpoint observer ( or anyone at rest with respect to the tracks) these flashes were emitted simultaneously, as shown by the expanding circles: However, for the railway car observer, events have to occur differently. He still detects the light from both flashes simultaneously, and they arrive when he is adjacent to the track observer. But unlike the track observer he has not remained halfway between the emission points the entire time. He is not an equal distance from the emission points when either of the flashes was emitted. But he must also measure the speed of light for each of the flashes as being the same relative to himself. But since the distances each of these flashes travel relative to him are not the same, in order for the light of the flashes to reach him simultaneously, they must have left at different times. And the sequence of the events for him occur like this: For the track observer, the flashes are emitted simultaneously, but for the railway observer they are not. This is the relativity of simultaneity: Events that are simultaneous in one inertial frame are not so according to another which in relative motion with respect to the first frame.
  4. 6 points
    I am pleased to now add CharonY and Strange to the list of gullible fools wonderful people willing to sacrifice their time for the greater good here at SFN. Congratulations!
  5. 6 points
    As I said in my previous post. Relativity makes no such claim when it comes to what an observer will visually see. This is a straw-man argument based on a misrepresentation of Relativity. To explain the difference between what the observer would visually see vs. what he is conclude is happening, we'll use some space-time diagrams. First consider two clocks separated by some distance and stationary with respect to each other. The blue line is our "observed" clock and the green line is our "observing" clock. The scale is such that light, shown as the yellow lines, is drawn at a 45 degree angle. Thus our observer will see light that left the blue clock when it read 1 arrive when his clock reads sometime after 3, and he will see the blue clock read 1 at that time. He also will see the light that left the blue clock when it read 2 arrive sometime after his clock reads 4. However, this does not mean that he will think or conclude that what he sees actually represents what time it is for the blue clock at those moments. That would be shown by the black horizontal lines, which shows that when the green observer sees the blue clock read 1, he knows that it actually reads the same as his own, or somewhat after 3, and when he sees the blue clock read 2, it actually at that moment reads somewhat after 4. Now let's add a third clock, one that is moving at 0.6c relative to the both clocks so that it and the blue clock are closing in on each other. This will be the red line in the following diagram. The light that left the red clock when it read 1 still arrives at the blue clock when the blue clock reads somewhat after 3. But the light that left when it read 2, arrives before the blue clock reads 4. The blue clock observer will in fact see the red clock ticking at a rate twice as fast as his own. But again he will not conclude that this means that this represents what time it actually is at the blue clock. When he sees the blue clock read 1 he will conclude that it reads a bit before 3 at that moment and when he sees it read 2, he will conclude that reads something before 3.5 at that moment, as shown by the black lines. He knows that the light carrying the image of the blue clock reading 2 left the blue clock when it was closer to him than the light carrying the image of it reading 1 left the blue clock. His has to account for this when determining when exactly that light left according to his own clock. As the black line from his clock reading 2 shows, the red clock didn't actually read 2 until sometime after his clock read 2. Thus after accounting for the time it took for the light from the red clock to reach him, he will conclude that the red clock is ticking slower than his own. This is time dilation. Now add yet another clock, this time so that it and the observer are receding from each other, as shown by the light blue line. Again the light leaving when it reads 1 arrives at the green observer when the green clock reads after 3. But the light leaving it when it reads 2 doesn't arrive until the green clock read after 5. The green observer will see the blue clock ticking at 1/2 the rate of his own. But this time, the light blue clock is further from the green when it reads 2 than it was when it read 1, and when the green observer takes this into account, it will turn out that when compared to his own clock, the light blue clock is ticking slower than his own, and by the same rate as he concluded that the red clock is ticking slow. The light blue clock exhibits the same time dilation as the red clock. This is what Relativity says is happening in the real universe, and this is not you you are trying to claim it says ( that an observer will always see a clock as running slow). If you are going to argue against a theory, you have to argue against the actual theory rather than some imagined version of your own creation.
  6. 5 points
    Hello everyone! It has been a while since I was active in the forum. Sure, I post a song here and there, but I just can't participate like I used to. I'm still having problems with my left hip even though I had a hip replacement back in April, 2017. Since then, I lost my job and medical insurance because I simply can't sit and write code for hours on end due to the extreme pain in my left hip. I lost my job as a software engineer in the middle of being treated by my doctor and they want a $500 deposit to continue treating me. Unfortunately, I don't have any income, I'm unable to work, and I've blown through my savings on living expenses and doctor bills. Most likely, I will need a revision done on my hip replacement to fix whatever is wrong so that I can go back to work and be a productive member of society. So, I'm reaching out to the community and asking for your help! The following link is to my GoFundMe campaign. I've attached photos of how my surgeries went so you will understand how much pain I'm actually experiencing. It's ok if you can't donate. You can help me out tremendously just by sharing this link! Every little bit helps!!! https://www.gofundme.com/clevelandraymond Thank you all so much! I truly appreciate anything you can do. Not only does your efforts mean the world to me, but also to my family as well.
  7. 5 points
    In previous threads, staff have mentioned that we have on occasion curtailed or removed the ability for people to use the reputation system. In previous versions of the forum software we were able to limit positive or negative reputation limits separately. This meant that the impact of people who wished to use the reputation system to target specific members was always low, and staff could easily reverse it. This no longer being the case means that the system is more open to being abused by people wishing to use it as a form of personal attack. Thankfully, we have had very few cases where staff have had to intervene. For those cases where we have had to do something, admin have created two new member groups with reputation point limits set to either 0 or 2, which limits the use of both positive and negative rep points.
  8. 5 points
    People are starting to argue with reputation points. I see more and more negatives, on both sides, even for valid points which deserve deliberation. It is a very sensitive subject but, I have come to know that everyone involved in this discussion is a sensible person. Discussion leads to understanding, so if you want your viewpoint understood, discuss it. Don't neg rep opposing views, they're just trying to make their viewpoint understood.
  9. 5 points
    You will find all relevant answers in this excellent resource: http://stopmasturbationnow.org/
  10. 5 points
    This is actually one of the few times there's a simple answer. Science describes god(s) as supernatural simply because they defy observation and prediction, two foundational tools of science. All of them. It's not an atheistic definition. Science describes what the natural world appears to be doing, and gods don't appear in the natural world. Pretty simple. By the way, one can be an atheist without rejecting anything. I'm perfectly willing to entertain the existence of a god if one decides to become observable. In that way, I think I'm actually much more open-minded than you.
  11. 5 points
    I'll let you know about a "rule of thumb" with regards to science and the scientific methodology. First and foremost, before you let your imagination run free, searching/looking for any new ideas that are not mainstream, please make an effort to get to know the mainstream product, and why it is mainstream and held as valid by most scientists...learn its predictions that have been shown to be valid...research the experiments that have supported its validity...check out all the observational data that support it. Then if you really and truly believe there is a serious fault with the particular incumbent model, start imagining why over so many years, the professionals and experts in that particular discipline, have not found this serious fault. You see that is the scientific method. Theories/models do not get established and then just rest on their laurels. They are conducting experiments everyday, testing the limits and accepted successes of the theories. Even long established theories are tested everyday...Even SR and GR are continually asked to live up to their deserved reputation. If you do that honestly, you will see why the chances of any Tom, Dick or Harry, coming to a forum open to all, to invalidate or propose some new model over-riding the incumbent is pretty close to zero. Best of luck anyway.
  12. 5 points
    Because the electron is not a classical particle (“little ball of mass and charge”), but a quantum object. As a first approximation, you can picture an electron as a 3D standing wave around the nucleus - you can only get standing waves of a given wavelength in specific places, which is why orbitals come in discrete levels. Crucially, there is a lowest energy level, which corresponds to the minimum distance an electron can be with respect to the nucleus (let’s assume here there is only one electron) - and that lowest energy level is not zero. Therefore the electron cannot fall all the way to the nucleus, it can only fall into its lowest energy level, which corresponds to an orbital that is still some distance outside the nucleus. This is a direct consequence of the laws of quantum mechanics, and coincidentally one of the questions that motivated the development of quantum mechanics in the first place.
  13. 5 points
    Here we finally have it! Proof of the existence of a creator? Best evidence yet!
  14. 4 points
    ! Moderator Note Menan was banned for breaking the rules, but for this sentence he should be banned from ever touching a computer again. This ignorance is willful.
  15. 4 points
    Yes, there ought to be a rule that you can leave those discussions, and just take part in the ones that interest you.
  16. 4 points
    I apologize on behalf of Science that Dark Matter is not yet fully understood. By all means, feel free to not treat us seriously until we rectify this egregious situation. You would think that by now we would have everything figured out. Mea culpa, mea culpa, mea maxima culpa.
  17. 4 points
    Why DNA manipulation? Why not just cut the fore-arm and stick a whip in there. Army of darkness style. Also: what are you talking about? That's the most random question I ever heard. Did you imagine that there is a whip gene? And you get it into your bloodstream and become whip-man?
  18. 4 points
    I am not a fan of general statements which imply parity between Democrats and Republicans. Unfortunately here in the U.S. we only have 2 major parties and despite various attempts by many to pretend they are both puppets cut from the same cloth there are measurable differences on nearly all matters between the two. When it comes to electing women for example there are 23 women in the Senate and 17 of them are Democrat. There are 84 women in the House and 63 of them are Democrat. So of the 107 women elected to congress in the U.S. 75% of them are Democrats. There are 3 women on the Supreme Court and all 3 were nominated by Democrats. Democrats were the first to run a Women, Geraldine Ferraro, on a Presidental ticket as VP in 1984 and the first to make a women their nominee for President in 2016. Republicans may nominate a Female for President in my lifetime. I am not saying it is impossible but I think it's not currently in the cards. Meanwhile on the Democratic side I will be surprised if either Harris, Warren, Gillibrand, or even Oprah aren't on the ticket as the nominee or VP. 75% of elected women in Congress being Democrat is not a coincidental number.
  19. 4 points
    Oh come on, INow… Let me bask in the glory of finally starting a topic which has lasted more than a page.
  20. 4 points
    By what you would visually see, then yes, you would see events occurring faster at Andromeda. Though you couldn't actually travel at the speed of light, just close to it. The equation for this relationship is fo = fs sqrt((1+v/c)/(1-v/c)) Where fo is the observed frequency, fs is the source frequency, and c is the speed of light. Note that if you make v=c then you end up with fo = fs sqrt(2)/0) And the division by 0 is undefined. ( but since travel at the speed of light is not allowed, this never arises.) However, just because you are seeing events unfold more quickly at Andromeda, does not mean that you would conclude that they were unfolding faster. Once you account for the effect caused by the decreasing distance between you and Andromeda, you would conclude that events were actually unfolding slower at Andromeda. For example, if you were traveling at 0.99c, you would see events at Andromeda as happening 14 times faster, but would conclude that they were happening 7 times slower. The 7 times slower would be due to time dilation, while the 14 times faster you see is due to Relativistic Doppler effect, which is a combination of time dilation and the effect caused by the decreasing distance. Even this is only a part of the whole picture. In order to understand what happens over the whole trip from Earth to Andromeda according to both Earth and ship would involve delving more deeply into Special Relativity.
  21. 4 points
    Depends. Some space probes have a very small plutonium reactor (e.g. Voyager), but they are not based on nuclear fission, but the natural decay of plutonium. Plutonium-238 is so highly radioactive that the heat of this decay is enough to produce electricity with it. Then there are other types of fission reactors, e.g. aqueous homogeneous reactors, that are pretty small: But they also work just with highly enriched Uranium-235. In the article the KEMA Suspension Test Reactor is also mentioned ("the reactor consisted of a reactor vessel (ø310 mm, content 18.3 liter"): My father worked at KEMA (but he was not associated with the reactor laboratory). You brought back a few melancholic associations with your question... And last but not least, there are experiments in Germany with nuclear power for smart phones. Sorry, I only found a German video of its promo, but I think you can understand what it is about, just looking at the video. It is worth it! https://www.youtube.com/watch?v=9-nezImUP0w
  22. 4 points
    I really wish you hadn't posted a link to that rag Here is a report from a slightly more reputable news source: http://www.bbc.com/autos/story/20161010-driving-the-saltwater-sports-car And: https://www.theskepticsguide.org/salt-water-car-not-so-fast Here is the Wikipedia age on the technology https://en.wikipedia.org/wiki/NanoFlowcell Sounds rather implausible (and the "saltwater" claim of the Daily Scum is just stupid).
  23. 4 points
    I asked a sincere question and I’m here to learn. I assumed you being the forum chemistry expert you could lend a hand. And yes, since you’re the chemistry expert - it is your job John.
  24. 4 points
    If only it was as simplistic as you think it is First of all, quantum physics is both completely deterministic and stochastic. What is deterministic is the evolution of the wave function - given any initial wave function, you can predict with certainty how that wave function will evolve over time (assuming you know the respective boundary conditions etc). However, what is stochastic is the relationship between the wave function, and physical observables - observables are represented by hermitian operators, and which of their eigenvalues you actually measure is - in general - purely probabilistic. For example - you send a stream of photons through a double slit. Given knowledge about the initial conditions (slit separation, photon frequencies, etc) you can predict with certainty what kind of an interference pattern you are going to get on your screen at the end of the experiment. However, you can not predict precisely where each individual photon will hit the screen, that is purely probabilistic. And we’re not even talking about the question which slit each photon goes through. So this is your third possibility - it’s come to be called “determined probabilities”. That’s the first thing. The other thing then is that determinism does not imply an absence of free will, and conversely, indeterminism does not imply that free will is necessarily possible. There are four different philosophical positions that encompass the four possibilities here: hard determinism, compatibilism, hard incompatibilism, and libertarianism. You can look these up yourself. The main point here is that this an ongoing debate, and there is no consensus about which is the correct one. And just to top things off - the human brain is a macroscopic system, and as such classical. So one would expect it to be deterministic. In reality however, in spite of its classicality, it is an example of a complex non-isolated, non-linear, chaotic system. So even if it were completely classical (which actually it isn’t anyway, since it’s fundamental building blocks are quantum mechanical), you still couldn’t predict its precise state very far into the future, because it is extremely sensitive to initial and boundary conditions, never even mind way too complex to mathematically model with currently available technology. It’s also an open feedback system, since it continuously receives external inputs, and generates responses that can modify those very inputs. So is the brain deterministic? You decide yourself, based on the above. Whatever your conclusion, what does that imply for free will? Again, you decide yourself, based on the philosophical positions on this subject matter. I think it is safe to say that there are no straightforward answers either way here.
  25. 4 points
    In a sense, getting to massless SM particles could be achieved by increasing the temperature in some region. But it would be more like an activation of the frozen Higgs field than a blocking. It is easier to explain coming from the high-energy side (high temperature), since that is the standard explanation for the Higgs mechanism: The Higgs proto-field (*) can be considered as an additional particle class to a Standard Model in which all of the other Standard Model particles are massless (**). It interacts with most of the other particle fields. But it also has a weird self-interaction which causes the energetically lowest state to not be at "no proto field" but at "some value of the proto-field". At low temperatures, where the Higgs proto-field is just lying around in its minimum, this means that the dynamic interaction terms of the Higgs proto-field with the other particles become some dull interaction of those particles with some sticky stuff that seems to lie around everywhere (***). In the mathematical description of the Standard Model time evolution, the associated terms that originally were terms of a dynamic interaction now become the mass terms for the other particles. If the minimum was at "no field", they would simply drop out (****). This "low-energy" limit actually covers almost all of the temperature ranges we can create on earth, and only recently did we manage to even create and see a few excitations of the Higgs proto-field around its minimum in specialized, very expensive experiments (-> confirmation of the Higgs-Boson at the LHC). So technically, I think we are very far away from creating the "massless particles" state in an experiment. But there is no theoretical reason why this would not be possible (*****). But as described, I would understand it to be less of a shielding of the Higgs field and more of an activation. And as a state with such a high amount of interaction between the fields. So I am not even sure if the common view of a few particles flying through mostly empty space and only rarely kicking into other free-flying particles would still make sense. Remarks: (*) I would just call it Higgs-field(s), but since the paper you cited seems to explicitly avoid using the name at this stage I may be wrong about common usage of the terms. Haven't been working in the field for over ten years. So I have invented the term proto-field for the scope of this post - it is also easier to understand than "doublet of complex scalar fields". (**) This is not exactly true because the particles are mixed and get renamed under the Higgs mechanism. But I'll pretend that does not happen for the sake of providing an answer that is easier to understand than reading a textbook. (***) Sidenote: In this state, the few excitations of the Higgs proto-field around its minimum are the infamous Higgs Boson. (****) Which is why you can always invent new fields that just happen to have no effect on anything we can see but magically make your particle cosmology equations work at very, very high energies (****) Except for the fact that some people still expect new physics and associated new particles at such high temperatures, which then again would have mass from another Higgs-like mechanism