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It's true that Ptolemaic cosmology stuck thinkers in a rut for a very long time; but what got us out of that rut was observation (and simplification). Copernicu

It's true that Ptolemaic cosmology stuck thinkers in a rut for a very long time; but what got us out of that rut was observation (and simplification). Copernicus saw that heliocentrism led to a simpler model that fit observation better (ironically he wanted to recover Ptolemy's perfectly circular orbits!). In turn, Kepler's perfectionism led him to ditch the circular orbit idea to yield the first accurate description of orbits as ellipses. Yes, transgression against long-held belief was necessary to move forward, but in every case the transgression explained observation. Transgression itself is undesirable. In fact, transgression unmotivated by observation is what powers the dark soul of the "crank", who is at best a time-waster and at worst a spreader of mental illness. Even Einstein did not produce (e.g. special relativity) out of whole cloth. He provided a consistent conceptualization of Lorentz contraction, itself the result of observing descrepencies in the motion of Jupiter's moons. The same could be said of the photoelectric effect, the ultraviolet catastrophe, and QM. All this to say that your statement "The rapid decline in progress in modern times would seem most likely to suggest that something we are taking as a fundamental assumption is probably wrong" is unsupported. Nothing could be more popular than questioning fundamental assumptions in science today! It could very well be that, as Sean Carroll puts it, we really know how everything larger than the diameter of a nuetron works! Moreover, we know that even if we find strangeness at tiny scales, our current theories WILL remain valid approximations, just like Newtonian mechanics are valid approximations of special and general relativity. The path to progress will not happen because a rogue genius finds something everyone missed and boldly questions assumptions long-held. Scientific revolution first requires an observation inconsistent with known models, but even the LHC hasn't given us even one of those. There is reason to think that GR, QM, and the standard model are all there is...until we do some experiments near a black hole!

somenameforme 2y ago
Heliocentrism from its earliest formulation was pretty bad for many reasons, including as you mentioned the desire to maintain circular orbits, as well as uniform velocities, epicycles, and more. You could easily pick a million holes in heliocentrism to 'disprove' it. And the geocentric view, as convoluted as it was, was observably accurate and predictive with 'holes' being plugged by simply having the entire dysfunctional model absorb them - e.g. by simply assuming retrograde motion as a natural phenomena, and otherwise - just add more epicycles. Heliocentrism was most fundamentally driven by somebody, with extremely poor interpersonal skills (which is much more the reason he was left living his final days in house imprisonment, rather than his theory itself), moving forward on his own somewhat obsessive bias. Similarly, with relativity. I have no idea what you mean by a 'consistent conceptualization' of Lorentz contraction, but length contraction was a completely ad hoc explanation for the Michelson Morley experiment. It's correctness was/is more incidental than anything else. Einstein did not cite Lorentz (or anybody for that matter), and I do not think that was unfair or egotistical of him. -- I'm also unsure of what you're referencing with Sean Carroll, but I'd offer a quote from Michelson of the Michelson-Morley experiment saying essentially the same, "The more important fundamental laws and facts of physical science have all been discovered, and these are now so firmly established that the possibility of their ever being supplanted in consequence of new discoveries is exceedingly remote.... Our future discoveries must be looked for in the sixth place of decimals." So convinced was Michelson that the 'failure' of his experiment was just a measurement issue that he made that comment in 1894, near to a decade after his experiment and shortly before physics and our understanding of the universe was about to revolutionary explode thanks to a low ranking patent inspector.
- simpaticoder 2y ago
  >I have no idea what you mean by a 'consistent conceptualization' of Lorentz contraction, but length contraction was a completely ad hoc explanation for the Michelson Morley experiment. It's correctness was/is more incidental than anything else. Einstein did not cite Lorentz (or anybody for that matter), and I do not think that was unfair or egotistical of him. In "On the Electrodynamics of Moving Bodies"[1] Einstein checks his derivation against Lorentz contraction. It's on page 20 of the referenced English translation. Lorentz' model was ad hoc, E derived it with only 2 postulates (equivalence principle; c invariance). Lorentz was indeed cited, and the cite is useful to connect E's theory to real-world observation. This is true whether or not you want to get pedantic about the meaning of "cite" vs "reference". 1 - https://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf https://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf Originally "Zur Elektrodynamik bewegter Koerper"
- kolanos 2y ago
  Max Planck famously said, "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it."
  - GoblinSlayer 2y ago
    Now we know how to prevent it: popularize ideas like "physics is mathematics", "shut up and calculate", "it's useless philosophy not worth to think about", "nobody can understand it, so it's useless to even try". Also a nice excuse for ignorance.
srean 2y ago
> Copernicus saw that heliocentrism led to a simpler model that fit observation better. That's not true, he didn't. Geocentric model of the time was a better fit of the data than the Copernican model. What Copernican model had was simplicity (at some cost to observational data fidelity). Making the heliocentric model approach (and breach) the accuracy obtained by the geocentric model took a lifetime of work by many people. As a kinematic model (description of the geometry of motions) as observed from Earth's reference frame geocentric is still pretty darn accurate. There's a reason why it is so. Compositions of epicycles are a form of Fourier analysis -- they are universal approximators. They can fit any 'reasonably well behaved' function. The risk is, and it's the same risk with ML, deep neural nets, that one (i) could overfit and (ii) it could generate a model with high predictive accuracy without being a causal model that generalises. Heliocentric model was proposed much much earlier than Copernicus but the counterarguments were non-ignorable. Reality, it turned out was very surprising and unintuitive.
- simpaticoder 2y ago
  Truth be told, I don't know much about Copernicus. He may indeed have been right but for the wrong reasons! If so, he's a very good example against my point that observation must precede successful revolution. It seems strange that the Catholic church took him so seriously if his claim was supported by his enthusiasm and not observation. It's definitely something I'd like to learn more about - any book recommendations?
  - srean 2y ago
    This history is absolutely fascinating. Let me find a blog post by Baez that covers a lot of that history. I don't think this history says anything against your point -- sometimes the time is just not right for the idea -- and even classical science can be very unintuitive and weird, so much so that common sense seems like very strong counter arguments against what eventually turn out to be better models. I of course learned this over many books, but the mind blanks out over which one to suggest. I think biographies of Copernicus and Kepler would be good places to start. Edit: you may find this interesting: https://news.ycombinator.com/item?id=42347533 https://news.ycombinator.com/item?id=42347533 HN do you know what happened to John Baez's blog that listed his multiparty blog posts ? They are a treasure trove that I do not want to lose. Azimuthproject too seems to have disappeared
GoblinSlayer 2y ago
Copernicus and Kepler did interpretations, not observations, they explained observations, but geocentrism explained observations too, so heliocentrism wasn't unquestionably superior.
CooCooCaCha 2y ago
I especially like your last paragraph. Even if our fundamental assumptions are wrong, current theories still work very well within appropriate bounds. And those bounds basically contain all practical scenarios here on earth. That's a big reason why it's hard to make progress on string theory, because we can't create scenarios extreme enough here on earth to test it. So even if our fundamental assumptions are wrong and some new theory is able to explain a bunch of new stuff, chances are it won't impact the stuff we can practically do here on earth, because scientists have already been doing the most extreme experiments they can, and so far progress is still stalled on fundamental physics.

somenameforme 2y ago

Heliocentrism from its earliest formulation was pretty bad for many reasons, including as you mentioned the desire to maintain circular orbits, as well as uniform velocities, epicycles, and more. You could easily pick a million holes in heliocentrism to 'disprove' it. And the geocentric view, as convoluted as it was, was observably accurate and predictive with 'holes' being plugged by simply having the entire dysfunctional model absorb them - e.g. by simply assuming retrograde motion as a natural phenomena, and otherwise - just add more epicycles. Heliocentrism was most fundamentally driven by somebody, with extremely poor interpersonal skills (which is much more the reason he was left living his final days in house imprisonment, rather than his theory itself), moving forward on his own somewhat obsessive bias. Similarly, with relativity. I have no idea what you mean by a 'consistent conceptualization' of Lorentz contraction, but length contraction was a completely ad hoc explanation for the Michelson Morley experiment. It's correctness was/is more incidental than anything else. Einstein did not cite Lorentz (or anybody for that matter), and I do not think that was unfair or egotistical of him. -- I'm also unsure of what you're referencing with Sean Carroll, but I'd offer a quote from Michelson of the Michelson-Morley experiment saying essentially the same, "The more important fundamental laws and facts of physical science have all been discovered, and these are now so firmly established that the possibility of their ever being supplanted in consequence of new discoveries is exceedingly remote.... Our future discoveries must be looked for in the sixth place of decimals." So convinced was Michelson that the 'failure' of his experiment was just a measurement issue that he made that comment in 1894, near to a decade after his experiment and shortly before physics and our understanding of the universe was about to revolutionary explode thanks to a low ranking patent inspector.

simpaticoder 2y ago
>I have no idea what you mean by a 'consistent conceptualization' of Lorentz contraction, but length contraction was a completely ad hoc explanation for the Michelson Morley experiment. It's correctness was/is more incidental than anything else. Einstein did not cite Lorentz (or anybody for that matter), and I do not think that was unfair or egotistical of him. In "On the Electrodynamics of Moving Bodies"[1] Einstein checks his derivation against Lorentz contraction. It's on page 20 of the referenced English translation. Lorentz' model was ad hoc, E derived it with only 2 postulates (equivalence principle; c invariance). Lorentz was indeed cited, and the cite is useful to connect E's theory to real-world observation. This is true whether or not you want to get pedantic about the meaning of "cite" vs "reference". 1 - https://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf https://www.fourmilab.ch/etexts/einstein/specrel/specrel.pdf Originally "Zur Elektrodynamik bewegter Koerper"
kolanos 2y ago
Max Planck famously said, "A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it."
- GoblinSlayer 2y ago
  Now we know how to prevent it: popularize ideas like "physics is mathematics", "shut up and calculate", "it's useless philosophy not worth to think about", "nobody can understand it, so it's useless to even try". Also a nice excuse for ignorance.

srean 2y ago

> Copernicus saw that heliocentrism led to a simpler model that fit observation better. That's not true, he didn't. Geocentric model of the time was a better fit of the data than the Copernican model. What Copernican model had was simplicity (at some cost to observational data fidelity). Making the heliocentric model approach (and breach) the accuracy obtained by the geocentric model took a lifetime of work by many people. As a kinematic model (description of the geometry of motions) as observed from Earth's reference frame geocentric is still pretty darn accurate. There's a reason why it is so. Compositions of epicycles are a form of Fourier analysis -- they are universal approximators. They can fit any 'reasonably well behaved' function. The risk is, and it's the same risk with ML, deep neural nets, that one (i) could overfit and (ii) it could generate a model with high predictive accuracy without being a causal model that generalises. Heliocentric model was proposed much much earlier than Copernicus but the counterarguments were non-ignorable. Reality, it turned out was very surprising and unintuitive.

simpaticoder 2y ago
Truth be told, I don't know much about Copernicus. He may indeed have been right but for the wrong reasons! If so, he's a very good example against my point that observation must precede successful revolution. It seems strange that the Catholic church took him so seriously if his claim was supported by his enthusiasm and not observation. It's definitely something I'd like to learn more about - any book recommendations?
- srean 2y ago
  This history is absolutely fascinating. Let me find a blog post by Baez that covers a lot of that history. I don't think this history says anything against your point -- sometimes the time is just not right for the idea -- and even classical science can be very unintuitive and weird, so much so that common sense seems like very strong counter arguments against what eventually turn out to be better models. I of course learned this over many books, but the mind blanks out over which one to suggest. I think biographies of Copernicus and Kepler would be good places to start. Edit: you may find this interesting: https://news.ycombinator.com/item?id=42347533 https://news.ycombinator.com/item?id=42347533 HN do you know what happened to John Baez's blog that listed his multiparty blog posts ? They are a treasure trove that I do not want to lose. Azimuthproject too seems to have disappeared

GoblinSlayer 2y ago

Copernicus and Kepler did interpretations, not observations, they explained observations, but geocentrism explained observations too, so heliocentrism wasn't unquestionably superior.

CooCooCaCha 2y ago

I especially like your last paragraph. Even if our fundamental assumptions are wrong, current theories still work very well within appropriate bounds. And those bounds basically contain all practical scenarios here on earth. That's a big reason why it's hard to make progress on string theory, because we can't create scenarios extreme enough here on earth to test it. So even if our fundamental assumptions are wrong and some new theory is able to explain a bunch of new stuff, chances are it won't impact the stuff we can practically do here on earth, because scientists have already been doing the most extreme experiments they can, and so far progress is still stalled on fundamental physics.