4 ms·

I have also seen many cranks in physics forums claim special relativity is largely an artifact due to the convention of Einstein synchronization, which they cla

I have also seen many cranks in physics forums claim special relativity is largely an artifact due to the convention of Einstein synchronization, which they claim is falsehood, as this convention adopt the equivalence between "one-way" and "two-way" speed of light as an axiom, and special relativity would be the natural consequence. But there's no reason to accept that, without accepting it, all the arguments for time dilation, etc, collapse, thus special relativity is invalid, then they return to non-relativistic classical mechanics and Galileo transformation. Not a mathematician or physicist, many things are not right in those arguments, I don't know what to say.

cygx 7y ago
You can safely ignore that: Relativity and classical mechanics make different predictions, and we've done the experiments. But if you travel into the weeds, a constant speed of light is not the only way to arrive at those predictions: In the extreme case, you could make the speed of light infinite in one direction if you slow it down to c/2 in the opposite direction. We don't do that because we like symmetries, and having light jump instantly from the surface of the sun to hit your head, then 'crawl' towards a mirror only to make an instantaneous jump into your eye seems rather weird...
- segfaultbuserr 7y ago
  > and we've done the experiments. I accept the findings of those experiments, such as [1]. But if you are a crank, you can always come up with conspiracy theories which claim "The Experiment X" back in the 1930s disprove it but is suppressed by the establishment. I used to read those posts as entertainment, but I stopped since then, as it stopped being fun after a month or so. > But if you travel into the weeds, a constant speed of light is not the only way to arrive at those predictions I think many major subjects of natural science have a "catch" like this. What is being written in popular science and most textbooks is merely a caricature of the subject, far from the full picture, but is considered "correct enough" to be a useful mental model (or physical model) for public consumption. For a simple example, an electric circuit is inherently an electromagnetic phenomenon, yet the fairy tale of "the flow of electron" is commonly used, it's an incomplete and flawed model even at DC. We use it because most people, myself included, are incapable of thinking the physical picture of vector calculus and solve PDE mentally, let alone Quantum Field Theory, not to mention the "truth" is only sometimes relevant and useful. Thus, if someone wants to engage in denialism or create FUD, one could just write something that is largely relevant but out-of-context, and say "you are being fooled, everything you know is wrong"! I suspect many pseudoscientific subjects, like the anti-vax movement or crank physics, frequency use this technique (or fell into it). Also, I once saw a LessWrong post that hypothesized: engineers are more likely to become cranks - because they are knowledgeable enough to spot a flaw in a physical model commonly used in the industry, and realize they are being fooled by thinking critically, but often they are completely unaware of the underlying history or context of the physics. I don't have data, but I definitely have seen something like this. I once saw a website by an RF engineer that claims GR is false, and built his own version using the ideas from antenna theory... [1] https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment#Recent_optical_resonator_experiments https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_exper...

cygx 7y ago

You can safely ignore that: Relativity and classical mechanics make different predictions, and we've done the experiments. But if you travel into the weeds, a constant speed of light is not the only way to arrive at those predictions: In the extreme case, you could make the speed of light infinite in one direction if you slow it down to c/2 in the opposite direction. We don't do that because we like symmetries, and having light jump instantly from the surface of the sun to hit your head, then 'crawl' towards a mirror only to make an instantaneous jump into your eye seems rather weird...

segfaultbuserr 7y ago
> and we've done the experiments. I accept the findings of those experiments, such as [1]. But if you are a crank, you can always come up with conspiracy theories which claim "The Experiment X" back in the 1930s disprove it but is suppressed by the establishment. I used to read those posts as entertainment, but I stopped since then, as it stopped being fun after a month or so. > But if you travel into the weeds, a constant speed of light is not the only way to arrive at those predictions I think many major subjects of natural science have a "catch" like this. What is being written in popular science and most textbooks is merely a caricature of the subject, far from the full picture, but is considered "correct enough" to be a useful mental model (or physical model) for public consumption. For a simple example, an electric circuit is inherently an electromagnetic phenomenon, yet the fairy tale of "the flow of electron" is commonly used, it's an incomplete and flawed model even at DC. We use it because most people, myself included, are incapable of thinking the physical picture of vector calculus and solve PDE mentally, let alone Quantum Field Theory, not to mention the "truth" is only sometimes relevant and useful. Thus, if someone wants to engage in denialism or create FUD, one could just write something that is largely relevant but out-of-context, and say "you are being fooled, everything you know is wrong"! I suspect many pseudoscientific subjects, like the anti-vax movement or crank physics, frequency use this technique (or fell into it). Also, I once saw a LessWrong post that hypothesized: engineers are more likely to become cranks - because they are knowledgeable enough to spot a flaw in a physical model commonly used in the industry, and realize they are being fooled by thinking critically, but often they are completely unaware of the underlying history or context of the physics. I don't have data, but I definitely have seen something like this. I once saw a website by an RF engineer that claims GR is false, and built his own version using the ideas from antenna theory... [1] https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment#Recent_optical_resonator_experiments https://en.wikipedia.org/wiki/Michelson%E2%80%93Morley_exper...