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If I am allowed to reflect a little on such postings, as the OP, or better, on the reactions to it. We see three kinds of reactions here: the 'beecee-reaction', the 'Janus-reaction', and the 'Markus-reaction'. (All are equally valid). Beecee's reaction is global, saying more or less that SR is empirically tested to the bone, so anybody thinking he found an error in relativity will have a very hard time: it is difficult to argue against endless observational tests, and the fact that SR is technically used, e.g. in particle accelerators. These would not work the way they do if we would not take SR in account. Janus' reaction is technical, to the point, showing where discountbrains makes errors in his argumentation. For me, with a limited understanding of SR, it is always a joy to read his exposés about errors made by 'Einstein-was-wrong!' (im)posters. Often his reactions improve my understanding another little bit. Markus' reaction I find, as a philosopher, the most interesting: it shows that SR belongs to the absolute fundamentals of our understanding of the world, of the laws of nature. This is even so much so that the Lorenz transformations can function as a filter for new laws of nature. If new found laws are not invariant under Lorenz transformations, they cannot be fundamental laws of nature. At most they are approximations. Historically, this has been a strong guide to find more fundamental laws of nature. The most astonishing example I find is Dirac: by discovering that the laws of QM, as they were known in his days, were not invariant under Lorenz transformations, and changing them by making them so, he was able to predict the spin of the electron and the existence of the anti-electron. Spin was already postulated on other grounds, but got its fundament with Dirac. The anti-electron was found about a year after Dirac's prediction. I am sure physicists here can come with more examples. I think e.g. that we could turn around Markus' argument: imagine we would only have known about the electric field and its impacts, but had not discovered the magnetic field. By making the electrical field Lorenz-invariant, the magnetic field would roll out. So, discountbrains, by saying 'Einstein had a fallacy' you are opposing the whole body of established physics. I think it are the outrageous sounding effects of time dilatation and length contraction that are so counter-intuitive, and are often presented as examples par-excellence of special relativity, that lay people think this is mainly what special relativity is about (just forgetting that E=mc2 also follows from special relativity), and that there must be an error. (And think that Einstein came to this theory and since then there was nothing anymore to it.) One could even defend that special relativity is not a physical theory, but a meta-physical theory (no, not metaphysical): every theory in physics must comply to special relativity, otherwise it is just an empirical approximation.

Hi, my name is ALine. I am new to this community and would like to put my opinion into the ring. It can generally be presumed that those who visit this site fall into 2 distinct categories. (1) An individual who is highly curious about the sciences, however, has no background within it what so ever which causes them to ask seemingly strange and simplistic questions. For this individual who is simply naturally curious, you need to be more gentle with them in your responses. It is comparative to a child who just wants to learn something new or wants to express new ideas to a community who is primarily focused toward discussing these ideas openly and fluidly. Depending upon the individual's method of delivering his thoughts or ideas it can be inferred that they are either scared of being judged for there ideas because it is being submitted into an open "arena" or they are just anxious about doing so. It is as if one of you were to go into say the arts without ever having picked up a paintbrush before and is expected to draw the Mona Lisa. By being accepting of all possible ideas it would allow for more individuals to become interested in the sciences. That is not to say that you should lessen your scrutiny of there ideas because hey let's face it if an idea is not rooted in reality then it no longer becomes a science, it is known as an art. However, instead of abruptly pointing out flaws or errors in work submitted slowly guide them in the right direction. Rome was not built in a day. The more they come on here the more they will realize their mistakes and the more they will come to realize that it is they themselves that are wrong. People really hate it when they are wrong, that is one of the consequences of the human psyche, probably. Some people will need to be moved quickly to build them up faster and some need to be moved more slowly and gradually. In doing so you can have a "LOT" more passionate individuals and have a lot more creative individuals share their ideas on here while at the same time being able to slowly start to accept criticism. (2) An individual who only wishes to prove that they are right no matter what else happens. No matter what you say or what you do they will always claim that their idea is the best idea because it proves this thing wrong, and then they do not themselves prove it wrong. Who says they know the material without knowing the material. These individuals are a little bit more tricky yet simple to deal with. Just kindly ask them to explain how they came to that conclusion. When they give an explanation simply provide your explanation for how that may be correct or incorrect. Slowly work with them to deconstruct their argument in a constructive way. See how they got to that eventual conclusion so that you can assist them in there logical and rational train of thought so that you can train them and they can help train you to become better rational thinkers. You may learn something new as well. This is not a game of "who is smartest" nor is it a fitness function in which only the "smartest" survive. What you all have created here is an academy for the free expression of knowledge between student and professor. The student must respect the professor for how much he knows and the teacher must respect the student for how much he wants to know. Both most work in a synergetic union in order to build on top of each other. The student will know more than the professor creatively and the professor will know more than the student in regards to the wisdom that they have acquired.

To address this scenario you have to take length contraction, time dilation and the relativity of simultaneity into account. For example the initial distances you give are as measured in the frame of the spaceships. This means that they measure the distance between the two planets as being length contracted (shorter than the distance that would be measured by someone at rest with respect to the planets). The distance that the lead ship measures between himself and Planet B, will be longer as measured by anyone at rest with respect to the planets. If he was traveling at 0.9999c relative to the planets, then the distance he measures as being 100 miles, will be measured as 7071 miles in the planet frame. You also say that when The lead ship is 100 miles from planet B, that the Trailing ship is 100 miles from planet A. Again, as measured from the frame of the ships. But this does not mean that the rest frame of the planets will measure The trailing ship as being 7071 miles from planet A when it measures the leading ship as being 7071 miles from planet B. When you say that the distances between the ships and planets are 100 miles at the same time, you are basically saying that if two ships had clocks in them and those clocks were synchronized to each other in the frame of the ships,then those clocks would read the same time (say 12:00) at the moment each ship was 100 miles from its respective planet. However, due to the relativity of simultaneity, according the planet frame, the clocks in the ship are not synchronized with each other. The clock in the trailing ship will read quite a bit ahead of the clock in the lead ship. The planet frame will agree that when the trailing ship's clock read 12:00 it was 7071 miles from planet A and when the lead ship' clock read 12:00 it was 7071 miles from planet B, but it will not agree that clocks on the two ships read 12:00 at the same moment. The sequence of events in the planet frame would go like this: The trailing ship clock will read 12:00 and it will be 7071 miles from planet A. At that time, the lead ship clock will read some time before 12:00 and will be greater than 7071 miles from planet B The distance between the trailing ship and planet A will increase while the distance between the lead ship and planet B will decrease. When the clock in the lead ship reads 12:00, the lead ship will be 7071 miles from planet B. The clock in the trailing ship will read quite a bit past 12:00 and the trailing ship will be more than 7071 miles from planet A. For a thorough analysis you would need to know both the proper distance between the ships (as measured by the ships) and the exact fraction of c the ships are moving with respect to the planets. Length contraction comes into play when you consider the muon frame. For the muon, its clock doesn't run slow, neither is its speed relative to the earth different from what the Earth measures as the muon's speed as being relative to the Earth. Thus the only way it could reach the ground in its lifetime at that relative speed would be for the distance between where it was created and the Earth's surface to be shorter for it than was when measured by the Earth.

back in the day I can see that maybe the air force was either just overwhelmed and was embarrassed they couldn't explain it or it was a cover up of some sort of secrete technology but by now you would think they would just some out and say what really was going on. I have toyed with the idea of some sort of plasma discharge or even plasma life but that is worse than aliens really...

In addition to what Mordred said, consider stellar fusion, where you get a balance between nuclear interaction rates and gravitational attraction. If you increase the gravitational attraction, you get fusion at much smaller gas densities, and would get to heavier elements fusing (up to iron; that shouldn't change) instead of stopping at an earlier stage.

He could PM his answers to you and ask you to copy-n-paste them to the thread...

ALine just PM’d me saying they could not post here. Unsure why?

I suspect for some people it feels unfair when after giving a lengthy explanation they've spent ages working on, they get a response that sounds like "you are wrong because of 'x', here is a link that explains things for you." They've already given this a lot of thought and obviously think they already understand. Most of the responses people here give focus on pointing out the errors with a speculation, and rightly so. But if you want to address the issue of appearing to reject an idea 'out of hand', it would be wise to stop telling them they are wrong, and present it in such a way that they arrive at the conclusion they are wrong all by themselves. Get them to accept the logic/evidence/math that is the foundation of the valid theory we are defending while leaving out the section where their flaw resides. If presented well, when you ask them to fill in the missing section, there will only be one possibility (the right one). My analogy is painting a picture for them while leaving out one section. When they look at the painting you want them to say "ah, obviously that section should be filled with the woman's face, not a pustulating boil as I previously suspected".

Indeed. And, it can be misleading, because people in this group sometimes pose the questions as "what if <alternative scenario>" or even appear to be proposing an alternative scenario rather than actually asking a question. But they are usually happy to be corrected and to learn. But without putting in the years of study required (and, quite possibly, but not necessarily, without being as smart).

If you change nothing but the gravitational constant, the universe would collapse before planets could form. Hence the fine tuning problem associated with Universe models as to why our universe is so finely tuned.

That's part of a long-term plan with Warren buffet's group and Morgan Chase to bring down healthcare costs to US businesses and their own employees in the US. Good luck to them.

Customization will force correct I believe. As technology replaces more jobs people will need to find customized niches for employment. A kid born today will need to be far more educated than I needed to be. Quality paying jobs requiring no experience or previous education are disappearing faster than glaciers. Things like 3D printing, self sufficient structures, A.I., and etc will demand more skill. The days where a company could just build 5,000 cookie cutter homes which are all identical out in some suburb are ending. Change is always hard. There are always growing pains. Ultimately the youth today have no choice but to become smart.

Janus has just answered this comprehensively - it‘s because of the issue of simultaneity. May I just add that it can be mathematically shown in a general manner that SR is fully self-consistent, i.e. it is not possible to construct any kind of real paradox using its axioms. This is independent of the specifics of the scenario. That‘s an interesting contradiction, because if relativity did not apply, then the very wire itself could not exist in real world (and neither could you, btw). This is because the quantum field theories that describe the behaviour of all the particles that make up the wire critically depend on the symmetries of relativity. Without it, elementary particles and their composites would either not exist at all, or have very different properties than the ones we observe. As for magnetism specifically, it actually follows from fundamental principles, so you don‘t even need to start with relativity. Suppose we have a potential 1-form A. The source-free part of the electromagnetic field then is, as usual for all such fields, [math]\displaystyle{F=dA}[/math] which is a 2-form. This naturally implies, via Poincare‘s Lemma, that [math]\displaystyle{dF=d(dA)=0}[/math] which is precisely the magnetic part of the Maxwell equations. Since both of the above relations are manifestly Lorentz covariant, on account of the transformation properties of the exterior derivative, the validity of relativity for magnetism is quite a natural consequence of this. It is hence just as correct to say that relativity falls right out of the fact that magnetism exists.

The stationary observer and the ships will not agree on those distances. Distance is contracted in the direction of motion, while our stationary observer is not going anywhere. Be at the maximum for one and a lesser value for the other two.

https://phys.org/news/2018-06-worthy-scientific.html Are we alone? The question is worthy of serious scientific study: Are we alone? Unfortunately, neither of the answers feel satisfactory. To be alone in this vast universe is a lonely prospect. On the other hand, if we are not alone and there is someone or something more powerful out there, that too is terrifying. As a NASA research scientist and now a professor of physics, I attended the 2002 NASA Contact Conference, which focused on serious speculation about extraterrestrials. During the meeting a concerned participant said loudly in a sinister tone, "You have absolutely no idea what is out there!" The silence was palpable as the truth of this statement sunk in. Humans are fearful of extraterrestrials visiting Earth. Perhaps fortunately, the distances between the stars are prohibitively vast. At least this is what we novices, who are just learning to travel into space, tell ourselves Read more at: https://phys.org/news/2018-06-worthy-scientific.html#jCp <<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> I most certainly am not "terrified" if the answer to the question of "are we alone" is no.....In fact if such was shown beyond doubt to be no, we are not alone, I would be incredibly excited, and hopeful of a close encounter of the third kind before I kicked the bucket.

Check out welding helmets.

This is one of the maps from Sebastian Muenster and is one of the early versions of the new world. You see "India" located in the upper left and Zipangri, which likely refers to Marco Polo"s naming of Japan (Zipangu). I.e. it is a map of the Islands (i.e. North and South America and the Caribbean Islands) of the New World which were presumed to lie by India, based on the knowledge available at that time (maybe 50-60 years after Columbus" journey).

Here we finally have it! Proof of the existence of a creator? Best evidence yet!

What does Benoit B. Mandelbrot's middle initial stand for? A: ...Benoit B. Mandelbrot

Would you close my account here, please. I've seen what I have expected so consider my presence here terminated, thank you.

Consider 2 spaceships going from planet A to planet B on the same path and with the same velocity very close to c. One is ahead of the other by several millions miles and is just a few 100 miles from planet B and the trailing one is a few 100 miles from planet A. Since they are going close to c an observer at rest watching them off to the side sees their separation actually appears very small. He adds their separation to the distances of each to the respective A and B planets and calculates the distance between the two planets and finds it now much smaller than he hnows it should be. How can this be? This same reasoning can be applied to Einstein's explanation of the electro-magnetic effect and it can be concluded his theory does not explain this either. Once I posted the spaceships example before on one of these sites and was told "This site is physics not math". I'm puzzled why I didn't counter this remark with, "This is science not religion". I will give details why relativity doesn't explain the magnetic effect of an electrical current through a wire later-its not complicated.

You have hit upon a paradox of this whole theory. No discontinuity needs to be considered. I hope my post on this made it on this board and wasn't deleted. You see u are not allowed to go against this Einstein religion. Distances that are immutable somehow magically change when u start calculating them using relativity. This is a fantacy. Yet SR predicts some things quite well like E=mc²