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  1. 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.
  2. 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.
  3. 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.
  4. 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.
  5. 5 points
    You will find all relevant answers in this excellent resource: http://stopmasturbationnow.org/
  6. 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.
  7. 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.
  8. 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.
  9. 5 points
    Here we finally have it! Proof of the existence of a creator? Best evidence yet!
  10. 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.
  11. 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?
  12. 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.
  13. 4 points
    Oh come on, INow… Let me bask in the glory of finally starting a topic which has lasted more than a page.
  14. 4 points
    While that's not outside the realm of possibilities, arguably a plausibility, it is not "essentially" doing that. If he is getting neg reps for understanding the difference, where you don't, there is something wrong with that.
  15. 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
  16. 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.
  17. 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.
  18. 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
  19. 4 points
    Let's put it this way: the Relativistic Doppler shift only depend on the relative velocity difference between the source at the time of emission and the receiver at the time of reception. For example, if the source is moving at 0.5 c relative to you at the time of emission, but you accelerate up to 0.5 in that same direction just before the light reaches you, you will measure no Doppler shift because relative velocity difference between you at reception and the source at transmission is 0. However, with cosmological red-shift we are dealing with the geometric expansion of space between the time of emission and reception. This stretches the light waves. So lets; say there was zero expansion of the universe at the moment of emission, then during some period between emission and reception there is some expansion. the light wave will share this expansion. Now the expansion stops before reception so that it is zero again. However, this does not mean that the light wave reverts to it original length. For that to happen, there would have to been a contraction of the universe. This means that you the observer will measure the red-shift caused by this period of expansion even though it no longer exists a the time of reception. So to put it simply, Relativistic Doppler shift only depends on the relative velocity difference between emission and reception ( You could change your velocity to many times while the light it traveling towards you, but the only thing that counts is your velocity at the moment of reception.) Cosmological red-shift is dependent on what occurs during the entire period that the light is traveling and not just the conditions at the "end points".
  20. 4 points
    Do you understand that scientists also observe nature and explain it without invoking a God. And do you also understand that nature is entirely consistent with there being no God? And do you therefore understand that nature is not evidence for God. It's like saying that it is theoretically possible that someone deliberately planted weeds in my garden. The weeds are there. So the phantom weed planter must exist!. The presence of weeds is consistent with His existence, but it's certainly not proof of it and, given that there are other more plausible explanations, it hardly counts as evidence for it. So, while nature is tangible, it's not evidence.
  21. 4 points
  22. 4 points
    A pretty cool simulation of everything in orbit around the Earth: http://stuffin.space/?intldes=1983-001A And an article about it here: https://www.universetoday.com/138981/this-is-the-coolest-everything-thats-orbiting-the-earth-right-now/
  23. 4 points
    Here's the problem with this. Anyone who has honestly delved into the scientific theory behind evolution would NOT be a "lifelong doubter". Also, the reasons those questions "keep nagging at" you is because you keep rejecting the best supported explanations for them, and for some reason refuse to honestly study the theory. You've come to prefer your imagined role as a skeptic, not realizing that true skeptics don't spend their whole lives on the fence.
  24. 4 points
    This is getting ridiculous, look, if God wanted publicity it would do some impossible shit that can be verified and tested; it doesn't so it can't. I think it's about time you stop invading multiple threads, with even a tenuous link to religion, with this unfathomable drivel. Please please, please...
  25. 4 points
    I find this video explaining the OP question very clearly. They even constructed a mechanical device visualizing the Lorentz transforms: