The REAL Reason You Don't Understand Relativity

almost every approach to teaching relativity Begins the same you get a set of pseudo-mystical sounding statements time and space are relative the universe has a speed limit there is no ether reality is a four-dimensional entity exhibiting curvature and so on then you are told certain empirical experiments prove the math and the math in turn proves the philosophy but does a mathematical formalism ever necessarily necessitate a single interpretation certainly this isn't the case with quantum mechanics which sports a rich diversity of viable and competing philosophies of course this might lead you to question are there other interpretations of Relativity out there and if so should we be teaching them this is dialect with the real reason you don't understand relativity [Music] last year we successfully debunked a major myth of general relativity which went along the lines of time dilation causes gravity at the time this idea appeared to us to be so ludicrously in contradiction with the basic tenets of Relativity that we assumed it had to be a product solely of the YouTube sphere but after publishing our video we discovered to our surprise that the misconception extended far beyond YouTube appearing in textbooks and even quoted by renowned physicists this of course got us wondering how could such brilliant people get their own Theory so incredibly wrong well the answer is because relativity very much like quantum mechanics is extremely confusing and it's doubtful anyone truly understands it of course with quantum mechanics this fact being openly acknowledged has led to a rich and intriguing field of Diversified interpretations but in relativity everyone carries on just as if they were all teaching one in the same interpretation the one they call Einstein's the problem is few people are acquainted with Einstein's actual work and don't know that Einstein never really had a solid interpretation of relativity most people teaching relativity are unaware for instance that Einstein himself didn't believe in the conventional solution to the twin paradox or in absolute acceleration that he didn't believe in black holes that he didn't believe in Cross terms of the line element that he didn't believe in the geometrization of gravity or most shockingly that he did Believe In The Ether or at least that he reversed his stance on it in 1920 when before an audience at the University of Leiden he declared that general relativity necessitates space b endowed with certain physical qualities and since the special theory of relativity does not compel us to deny ether that therefore there exists an ether indeed a number of major shifts in Einstein's interpretation of Relativity can be traced throughout his lifetime and he died never really having made up his mind about what the Theory actually meant in his wake he left an immense philosophical vacuum which modern physicists are still trying to fill in with their own ideas today the result is an extraordinary and inordinate confusion which you can see clearly on display in the wide number of personal interpretations that professionals give to their explanations such differing interpretations can be found in any number of YouTube videos but today we're going to pick on one in particular Sabina hasenfelder's why you misunderstand relativity now we enjoy sabina's Channel and we were in fact greatly appreciative of this video on the whole since it corroborated our own video from a few months earlier about how you're accelerating up at the surface of the Earth but on the flip side this video also brings several contradictory statements into immediate proximity to one another and in doing so demonstrates just why relativity is so badly in need of better interpretations no this isn't an attack personally on Sabina in any way and she has plenty of great content but we do feel that her arguments in this video are representative of the confusion of the greater physics Community as a whole now the video gets off to a strong start with Sabina emphasizing the formalism of Relativity over its philosophy and explaining that our confusion about relativity stems from the simple fact that we're treating time dilation too literally that is taking it to be something physically real when it's rather just an artifact of how we choose to do measurements and draw up coordinates the time that passes between two events is not the time on the coordinate axis that's just a label it's convention it has no physical meaning this is what people often call time dilation I'd call this pseudo-time dilation because it's a meaningless comparison why would you care about the coordinate time it's just a label it has no physical meaning for Bob all of this is great and it seems very in keeping with Einstein's original 1905 special relativity paper wherein you won't find too many Grand statements about the nature of space and time itself but rather just a simple demonstration of how adopting light as a basis for our spatial temporal measurements conveniently reproduces the already well known at the time Lorenz transformations but a few minutes later into the video while Sabina is discussing the twin paradox she gives us this statement the way he travels this is the real-time dilation it comes from the acceleration this is the real-time dilation the real-time dilation the real-time deletion like what first she was telling us we were confused about relativity because we were treating time dilation too literally and now she's saying time dilation is something literal and to understand the theory you need to accept a fact that only minutes earlier was stated to be the source of your confusion again like what let's slow down for a second more precisely Sabine is saying here that time dilation is only real for the special case of acceleration but as she implies in the beginning it's the idea of any sort of time dilation being real that confuses people indeed by saying that time dilation is only real for acceleration she thinks she's resolving the source of our confusion but she's not she's merely transferring it from the case of velocity to the case of acceleration secondly she neglects to mention that observers who aren't accelerating will not perceive the same manner of time dilation as those who are in a uniform gravitational field for instance observers who are stationary within the field I.E those who are accelerating will see clocks at different positions ticked at different rates but an observer Free Falling in that field you'll see those same clocks all ticking at the same rates no matter what their location thus any Observer not sharing in the acceleration won't be able to agree on the time dilation of the clocks so by no means can we claim accelerated time dilation to be any more or less real than velocity-based time dilation they both are coordinate Observer dependent phenomena now Sabina does point out that a more meaningful comparison of time ought to happen when observers are rejoined at the same place to compare clocks which is why she brings up the twin paradox but she gets something very wrong when she says that the real-time dilation comes from acceleration the asymmetry of the Paradox certainly comes from acceleration but to Alice Bob's velocity or kinematical time dilation is very real and the cause of his slowed aging and to Bob Alice's kinematical time dilation is likewise also very real but now in his case there's an additional accelerative time contraction which he has to add atop the kinematical dilation thus it's actually the kinematical and accelerative time dilations slash contractions taken together that describe the real proper time if you leave either of them out the math fails now if you want a quick and dirty rundown of the math we recommend you watch this short video by minute physics it's simple and easy to follow and it will give you the necessary insights about why kinematic and accelerative time dilations and contractions need to be taken together indeed saying only accelerative time dilation is real while kinematical time dilation isn't is not only incorrect it's also not an explanation you'll come across in any textbooks or historical works so Sabinas being a little disingenuous here and claiming she's teaching Einstein's interpretation as she's actually just teaching her own additionally earlier in the video she actually rejects Einstein's preferred explanation to the twin paradox which is the gravity-based one of course as we discussed earlier it's likely she's entirely unaware that Einstein even had a preferred solution to the twin paradox but this just demonstrates our point that nobody knows exactly what interpretation of Relativity they are teaching and generally they just fill in the gaps in their understanding with their own ideas here sabina's own ideas are quite in confusion as it's clear she can't decide what level of ontological reality to ascribe to the phenomenon of time dilation indeed physicists being unable to make up their minds about what the meaning of time dilation actually is is probably the biggest source of confusion in relativity and why you get such backwards ideas like time dilation causes gravity is time dilation something real something that should modify our idea of true immutably flowing time or is it just an artifact of how we've chosen to formulate our Theory and draw up coordinates this is where the formalism of Relativity doesn't provide any clear answers and consequently where the personal interpretations begin to flow if we want to treat time dilation as something real then sense different observers don't perceive the same manner of time dilation as one another we seemingly have to accept a solipsistic world view where different observers can construct different narratives of their existence on the other hand if we reject the reality of time dilation we're left scratching our heads over just how it comes about that certain clocks can be empirically observed to run slower or faster than others but what if it were the case that there were other interpretations of Relativity out there interpretations that reproduced the formalism but which steered clear of the heavy-handed space and time altering pseudomysticism of Relativity altogether interpretations in which there was no time dilation or spatial contraction to begin with no relativity of simultaneity or funky stretching or shrinking of measuring instruments would you feel you deserve to know what these interpretations are or do you think physicists should go on teaching relativity as it currently stands a theory with a perfectly functioning formalism but with its philosophy caught in a limbo so uncertain that even Einstein couldn't make up his mind about it well we can't make that decision for you but we can say that if we want to move towards a more consistent interpretation of relativity we need to re-examine one Assumption of Relativity in particular the Assumption of absolute acceleration indeed it's this assumption which Sabina uses to justify her interpretation that only accelerative time dilation is real but it's an assumption Einstein could never bring himself to accept indeed if you want to know Einstein's actual thoughts on the topic we suggest you read his 1913 paper entitled on the relativity problem because you might be surprised by what you find there we also suggest you watch sabina's video more carefully around the 17 minute Mark and ask yourself why she says that the spring which is brought in there has to come from outer space indeed a more thorough examination of the problematic notion of absolute acceleration will help guide us towards a better interpretation of relativity we're saving a full treatment of that topic for another video but for the moment we can with certainty say that this statement Sabina gives us at the end of her video is not correct and rather than clarifying things for her viewers it merely demonstrates her own confusion about the theory which of course brings us to the real reason you don't understand relativity you don't understand it because the people teaching it to you don't understand it at the end of the day this isn't a huge deal as quantum mechanics demonstrates that you can teach a formalism just fine without the accompanying Clarity of philosophical principles however the first step to overcoming a problem is admitting that you have one and relativity unlike quantum physics suffers from a serious case of denial but if you like us are after the truth then you know no harm can come of asking critical questions and exploring new ideas so hold on to your socks because our channel is about to move into Uncharted Territory this has been dialect stay tuned

Channel: Dialect

Views: 124,157

Keywords: physics, sabine hossenfelder, space and time, relativity, special relativity, general relativity, myth, conspiracy, math, time dilation, lorentz

Id: an6JiBLQqXY

Length: 15min 33sec (933 seconds)

Published: Sat Apr 29 2023