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That would be true if young scientists wouldn’t continuously make successful predictions based on cosmological principle among other observable effects of the g

by Svoka 5y ago

That would be true if young scientists wouldn’t continuously make successful predictions based on cosmological principle among other observable effects of the general relativity and standard model. Make observable prediction, coherent thesis, then we’ll talk. Of course our models are not perfect, but it is best we have. Physics so far never dealt in “fundamental truths”, just good enough models. So far, this is best we got.

zeven7 5y ago
I'd argue that Einstein in particular cared a lot about "fundamental truths". Not everyone can be Einstein, but I'm glad some people care about asking deeper questions.
- kkylin 5y ago
  I don't disagree with your point, but do want to add that not publishing on "fundamental truths" isn't the same as not asking those questions. Not everyone's going to have something novel, plausible, and fundamental to say on a regular basis, hence most publications (even if everyone's asking these questions, which granted they're probably not) are going to be much more incremental.
- rich_sasha 5y ago
  Ironically, it was Einstein who introduced the “cosmological constant” (and thus indirectly dark energy). I think later in life he called it a glorified fudge factor and his biggest regret.
  - raattgift 5y ago
    Wikipedia covers this sufficiently at https://en.wikipedia.org/wiki/Cosmological_constant#Sequence_of_events_1915%E2%80%931998 https://en.wikipedia.org/wiki/Cosmological_constant#Sequence... The five-line tl;dr: non-expanding cosmologies with no big bang but lots of galaxies tend to collapse in finite time. One can avoid collapse with a positive cosmological constant. That approach predated the work of Hubble (expansion) and Lemaître (big bang). Expanding cosmologies with a sufficiently large initial big bang do not need a cosmological constant to keep expanding forever. Einstein, not being stupid, recognized that and carried on. Since 1998: an accelerating expanding universe is inconsistent with just a single big bang as impulse, but is consistent with a small positive cosmological constant. Einstein and Schrödinger certainly discussed whether to treat the cosmological constant as an energy entering into the right hand side of the Einstein Field Equations instead of a multiplier on the metric in the left hand side: [Harvey 2012] https://arxiv.org/abs/1211.6338 https://arxiv.org/abs/1211.6338 Their conclusion is that choice of side is principally a matter of aesthetics, and that remains true today. Harvey2012 §5 is a good reminder not to put too much weight into the early days of general relativity. Exact solutions were few and simple but still extraordinarily hard to work with by hand. Numerical approaches didn't exist, nor did formalisms that provide post-Newtonian approximations that are more tractable. Realistic distributions of matter were largely as-yet undiscovered (compare 1917 introduction of cosmological constant and low estimates of the number of spiral galaxies in the sky, their mass, and the light-travel distance to them: https://en.wikipedia.org/wiki/Great_Debate_(astronomy) https://en.wikipedia.org/wiki/Great_Debate_(astronomy) which came later). Einstein's adaptation to the flood of astronomical discoveries during his productive lifetime is part of what made him Einstein rather than any less celebrated figure.
- simonh 5y ago
  He cared about fundamental truths, but he didn’t think we had them. “ all our science, measured against reality, is primitive and childlike — and yet it is the most precious thing we have.” The best we can ever say about science is that it is useful, that’s what truth means in science, that it produces accurate predictions. Truth in any deeper sense is a matter for philosophers.
  - zeven7 5y ago
    He didn't think we had those truths yet but I do think it's clear he thought it was the job of scientists (not only philosophers) to discover them. That's his major motivation behind the EPR paradox, general relativity, and the search for a greater theory. If you look at what he did, he wanted to figure out what is true. General relativity answered Newton's "metaphysical" question about how gravity could act on bodies at a distance.
- secondaryacct 5y ago
  And he made mistakes based on his bias on what "should" be like all of us. Not everyone can do maths like Einstein, but on this particular point everyone can say "God doesn't do X" and be wrong.
- Svoka 5y ago
  Einstein is a great mind. His importance is greatly overblown by pop culture and politics. Outstanding mind, but not unique. He built small bricks on shoulders of titans and with lots of help from his co authors. Would he be born 50 years earlier, none of his discoveries were made. Anyway. This is outside the topic. Every person who does physics cares about "fundamental truths" But even such great minds as Einstein build their models understanding limits of the model, in best case scenario.
  - zeven7 5y ago
    This is an easy and naive view of Einstein. Would you argue the same for Newton? The truth is special relativity was going to be discovered soon regardless, general relativity was a leap that required a leader as unique as Einstein, Newton, Galileo. Of course he had a lot of help from Hilbert. I don't consider collaborating on a discovery as grounds to dismiss a scientist as "not unique".

by Svoka 5y ago

zeven7 5y ago

I'd argue that Einstein in particular cared a lot about "fundamental truths". Not everyone can be Einstein, but I'm glad some people care about asking deeper questions.

kkylin 5y ago
I don't disagree with your point, but do want to add that not publishing on "fundamental truths" isn't the same as not asking those questions. Not everyone's going to have something novel, plausible, and fundamental to say on a regular basis, hence most publications (even if everyone's asking these questions, which granted they're probably not) are going to be much more incremental.
rich_sasha 5y ago
Ironically, it was Einstein who introduced the “cosmological constant” (and thus indirectly dark energy). I think later in life he called it a glorified fudge factor and his biggest regret.
- raattgift 5y ago
  Wikipedia covers this sufficiently at https://en.wikipedia.org/wiki/Cosmological_constant#Sequence_of_events_1915%E2%80%931998 https://en.wikipedia.org/wiki/Cosmological_constant#Sequence... The five-line tl;dr: non-expanding cosmologies with no big bang but lots of galaxies tend to collapse in finite time. One can avoid collapse with a positive cosmological constant. That approach predated the work of Hubble (expansion) and Lemaître (big bang). Expanding cosmologies with a sufficiently large initial big bang do not need a cosmological constant to keep expanding forever. Einstein, not being stupid, recognized that and carried on. Since 1998: an accelerating expanding universe is inconsistent with just a single big bang as impulse, but is consistent with a small positive cosmological constant. Einstein and Schrödinger certainly discussed whether to treat the cosmological constant as an energy entering into the right hand side of the Einstein Field Equations instead of a multiplier on the metric in the left hand side: [Harvey 2012] https://arxiv.org/abs/1211.6338 https://arxiv.org/abs/1211.6338 Their conclusion is that choice of side is principally a matter of aesthetics, and that remains true today. Harvey2012 §5 is a good reminder not to put too much weight into the early days of general relativity. Exact solutions were few and simple but still extraordinarily hard to work with by hand. Numerical approaches didn't exist, nor did formalisms that provide post-Newtonian approximations that are more tractable. Realistic distributions of matter were largely as-yet undiscovered (compare 1917 introduction of cosmological constant and low estimates of the number of spiral galaxies in the sky, their mass, and the light-travel distance to them: https://en.wikipedia.org/wiki/Great_Debate_(astronomy) https://en.wikipedia.org/wiki/Great_Debate_(astronomy) which came later). Einstein's adaptation to the flood of astronomical discoveries during his productive lifetime is part of what made him Einstein rather than any less celebrated figure.
simonh 5y ago
He cared about fundamental truths, but he didn’t think we had them. “ all our science, measured against reality, is primitive and childlike — and yet it is the most precious thing we have.” The best we can ever say about science is that it is useful, that’s what truth means in science, that it produces accurate predictions. Truth in any deeper sense is a matter for philosophers.
- zeven7 5y ago
  He didn't think we had those truths yet but I do think it's clear he thought it was the job of scientists (not only philosophers) to discover them. That's his major motivation behind the EPR paradox, general relativity, and the search for a greater theory. If you look at what he did, he wanted to figure out what is true. General relativity answered Newton's "metaphysical" question about how gravity could act on bodies at a distance.
secondaryacct 5y ago
And he made mistakes based on his bias on what "should" be like all of us. Not everyone can do maths like Einstein, but on this particular point everyone can say "God doesn't do X" and be wrong.
Svoka 5y ago
Einstein is a great mind. His importance is greatly overblown by pop culture and politics. Outstanding mind, but not unique. He built small bricks on shoulders of titans and with lots of help from his co authors. Would he be born 50 years earlier, none of his discoveries were made. Anyway. This is outside the topic. Every person who does physics cares about "fundamental truths" But even such great minds as Einstein build their models understanding limits of the model, in best case scenario.
- zeven7 5y ago
  This is an easy and naive view of Einstein. Would you argue the same for Newton? The truth is special relativity was going to be discovered soon regardless, general relativity was a leap that required a leader as unique as Einstein, Newton, Galileo. Of course he had a lot of help from Hilbert. I don't consider collaborating on a discovery as grounds to dismiss a scientist as "not unique".