4 ms·

There used to be this theory of Phlogiston, which was a material substance of heat (if you put a lit match under a brick, phlogiston would move from the match t

There used to be this theory of Phlogiston, which was a material substance of heat (if you put a lit match under a brick, phlogiston would move from the match to the brick.) Today of course, this sounds ridiculous. But my physics teacher was always keen to point out that the people involved weren't stupid and that it was an important theory because it was a good starting mental model of how things actually worked and led to our better understanding today. I wonder if dark matter is similar. It's not flat wrong, it's the best explanation that we have so far and in it will lead us into another breakthrough of understanding. 1 - https://en.wikipedia.org/wiki/Phlogiston_theory https://en.wikipedia.org/wiki/Phlogiston_theory

mikeash 10y ago
Phlogiston is an absolutely reasonable theory given what was known at the time. It's a really interesting example. Phlogiston is basically negative oxygen. It's very similar to how our traditional notion of electrical current moves in the opposite direction from the actual electrons, because people had no idea whether positive or negative charge was the one that moved around, and they just arbitrarily assigned the positive charges as the ones that moved. It doesn't quite work that way, because charges can be positive and negative, whereas oxygen can only be positive or zero. But until you're able to do some pretty careful measurements, or create a good vacuum, it's hard to tell. It's a great analogy. Phlogiston theorized that combustion involved an undetectable (with the technology of the day) substance. That substance was investigated over time and the theory was refined until eventually people figured out that the sign was inverted. If you think of "the opposite of oxygen" as still being a pretty solid theory, not absurd, it comes out looking pretty good.
- saalweachter 10y ago
  Oxygen is also really weird from a certain point of view. Your fuel is exhausted by gaining something. Your fuel may even still be there, but you can't keep burning it because there is too much of an extra thing, which is also necessary for burning.
badosu 10y ago
This also reminds me of the Michelson-Morley experiment[0]. A pretty sofisticated setup (at the time) was preparated to prove the fairly established idea that light propagated through Aether. Well, the failure of the experiment motivated a lot of scientists to improve and test other models. I can't exactly recall right now, but Einstein's work was supported by the work of many other scientists. It's not the case that at the time an alternative theory of gravity, space and time was unpopular, as you can see in the works of Lorentz and Minkowski for example. Not to degrade Einstein's contribution, but to shed light on how the actual scientific process diverges from the popular perception (even among fairly educated people). In quantum mechanics and analyzing the history of it's development this is much more evident. E.G. Max Planck on his solution to the Ultraviolet Catastrophe[1]: "My unavailing attempts to somehow reintegrate the action quantum into classical theory extended over several years and caused me much trouble." 0: https://simple.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment https://simple.wikipedia.org/wiki/Michelson%E2%80%93Morley_e... 1: https://en.wikipedia.org/wiki/Ultraviolet_catastrophe https://en.wikipedia.org/wiki/Ultraviolet_catastrophe
- poofyleek 10y ago
  Michelson-Morley experiment failed to substantiate the existence of ether. That was 1887. Much after that, in 1905, Einstein's special theory of relativity stated you don't need ether and any medium for light to travel, as long as one abandons the idea of absolute time. The comment by Mordehai Milgrom, " the emperor has no clothes, that dark matter is our generation’s ether." rings true to me. So far no dark matter has been found by LHC. They used to say 95% of the universe was dark matter. Now they say 68% is dark energy and 27% dark matter. Still only 5% normal matter. Could it be that there is 100% normal matter, 95% of which are transient and temporal in vacuum? If we were to follow Milgrom, and not invent substances, it seems plausible that we still have more math work to do.

mikeash 10y ago

Phlogiston is an absolutely reasonable theory given what was known at the time. It's a really interesting example. Phlogiston is basically negative oxygen. It's very similar to how our traditional notion of electrical current moves in the opposite direction from the actual electrons, because people had no idea whether positive or negative charge was the one that moved around, and they just arbitrarily assigned the positive charges as the ones that moved. It doesn't quite work that way, because charges can be positive and negative, whereas oxygen can only be positive or zero. But until you're able to do some pretty careful measurements, or create a good vacuum, it's hard to tell. It's a great analogy. Phlogiston theorized that combustion involved an undetectable (with the technology of the day) substance. That substance was investigated over time and the theory was refined until eventually people figured out that the sign was inverted. If you think of "the opposite of oxygen" as still being a pretty solid theory, not absurd, it comes out looking pretty good.

saalweachter 10y ago
Oxygen is also really weird from a certain point of view. Your fuel is exhausted by gaining something. Your fuel may even still be there, but you can't keep burning it because there is too much of an extra thing, which is also necessary for burning.

badosu 10y ago

This also reminds me of the Michelson-Morley experiment[0]. A pretty sofisticated setup (at the time) was preparated to prove the fairly established idea that light propagated through Aether. Well, the failure of the experiment motivated a lot of scientists to improve and test other models. I can't exactly recall right now, but Einstein's work was supported by the work of many other scientists. It's not the case that at the time an alternative theory of gravity, space and time was unpopular, as you can see in the works of Lorentz and Minkowski for example. Not to degrade Einstein's contribution, but to shed light on how the actual scientific process diverges from the popular perception (even among fairly educated people). In quantum mechanics and analyzing the history of it's development this is much more evident. E.G. Max Planck on his solution to the Ultraviolet Catastrophe[1]: "My unavailing attempts to somehow reintegrate the action quantum into classical theory extended over several years and caused me much trouble." 0: https://simple.wikipedia.org/wiki/Michelson%E2%80%93Morley_experiment https://simple.wikipedia.org/wiki/Michelson%E2%80%93Morley_e... 1: https://en.wikipedia.org/wiki/Ultraviolet_catastrophe https://en.wikipedia.org/wiki/Ultraviolet_catastrophe

poofyleek 10y ago
Michelson-Morley experiment failed to substantiate the existence of ether. That was 1887. Much after that, in 1905, Einstein's special theory of relativity stated you don't need ether and any medium for light to travel, as long as one abandons the idea of absolute time. The comment by Mordehai Milgrom, " the emperor has no clothes, that dark matter is our generation’s ether." rings true to me. So far no dark matter has been found by LHC. They used to say 95% of the universe was dark matter. Now they say 68% is dark energy and 27% dark matter. Still only 5% normal matter. Could it be that there is 100% normal matter, 95% of which are transient and temporal in vacuum? If we were to follow Milgrom, and not invent substances, it seems plausible that we still have more math work to do.