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No, that is not how science actually progresses, it is an idealised view of it at best. Thomas Kuhn wrote "The Structure of Scientific Revolutions" back in the

No, that is not how science actually progresses, it is an idealised view of it at best. Thomas Kuhn wrote "The Structure of Scientific Revolutions" back in the 1960s. Plank's principle stated "Science progresses one funeral at a time". Scientists are also human and will tend to defend existing ideas. In cosmology the arguments over LCDM, dark matter and dark energy have been raging for decades. Dark matter people like to say that the Bullet Cluster is incontrovertible evidence of dark matter; MOND people don't agree and point to other aspects they claim refute dark matter! It's gonna take a long time for it all to shake out.

SubiculumCode 1mo ago
Not an expert, but isn't your LCDM vs MOND example assymetric? Like different kinds of data supports each model very well, and so reconciliation isn't simple? Moreover, your objection that science progresses one funeral at a time is exaggerated, even if it is real, it's not necessarily all that strong: https://pmc.ncbi.nlm.nih.gov/articles/PMC6814193/ https://pmc.ncbi.nlm.nih.gov/articles/PMC6814193/
- MattPalmer1086 1mo ago
  Certainly true that the data can be viewed in many different ways. Often the same data is used by both sides! The funeral thing isn't really a position I strongly hold; it's a pithy comment that points out science is a human endeavor and maybe not quite as objective as it is often presented. But science as a whole is ultimately a self correcting methodology, even if it might take longer than we would want and doesnt always get it right.
layer8 1mo ago
MOND people have become a small minority. In addition to the galaxy cluster observations, MOND doesn’t match the CMB power spectrum, while ΛCDM does, and various very precise measurements within the solar system also contradict MOND. This was different 30-40 years ago, but since then, as evidence has strongly mounted against MOND, a lot of “shaking out” has already taken place.
- MattPalmer1086 1mo ago
  Well, MOND is not a cosmological theory or relativistic - there are some different versions that attempt that. MOND itself can't be used to match the CMB spectrum. It has always been a minority position - but it is interesting to see a different perspective. ΛCDM is not without it's own problems. Not least that when new observations contradict it, it just gets tweaked - since we still have no idea what the CDM, if it does exist, actually is. It does not have a great predictive record; it is good at explaining obervations after the fact (the CMB notwithstanding). I am interested to know what the measurements within the solar system are that you refer to. I had thought this was far too small a scale to prove anything about MOND or CDM.
  - suuuuuuuu 1mo ago
    > It does not have a great predictive record; it is good at explaining obervations after the fact (the CMB notwithstanding). Can you elaborate on what you mean? LCDM hasn't been "tweaked" since \Lambda was established in the 90s (at least, not for large-scale cosmological observations). The current discrepancies are all at the precision level (<10%) rather than a qualitative O(1) difference. An important (but not dispositive) nuance is that LCDM well explains all observations individually; the percent-level tensions arise only between fits to datasets, meaning unknown systematics remain a viable explanation. The unknown fundamental nature of CDM (as important a problem as it is) seems irrelevant to arguments about LCDM's predictivity (as a cosmological model).
    - MattPalmer1086 1mo ago
      A couple of examples: 1. LCDM predicted hierarchical formation of large galaxies through aggregation. JWST seems to show this is not what happens (large galaxies at early times). I am sure it can be made to work, but it was not a prediction. 2. Constant Lambda - recent obervations seem to show it may be changing (OK - that is more built into the theory rather than being a prediction). By the way, I am not saying LCDM is not massively successful. It can clearly be used to explain a lot of things. I am saying that I am not aware of many things it successfully predicted ahead of observations being made.

SubiculumCode 1mo ago

Not an expert, but isn't your LCDM vs MOND example assymetric? Like different kinds of data supports each model very well, and so reconciliation isn't simple? Moreover, your objection that science progresses one funeral at a time is exaggerated, even if it is real, it's not necessarily all that strong: https://pmc.ncbi.nlm.nih.gov/articles/PMC6814193/ https://pmc.ncbi.nlm.nih.gov/articles/PMC6814193/

MattPalmer1086 1mo ago
Certainly true that the data can be viewed in many different ways. Often the same data is used by both sides! The funeral thing isn't really a position I strongly hold; it's a pithy comment that points out science is a human endeavor and maybe not quite as objective as it is often presented. But science as a whole is ultimately a self correcting methodology, even if it might take longer than we would want and doesnt always get it right.

layer8 1mo ago

MOND people have become a small minority. In addition to the galaxy cluster observations, MOND doesn’t match the CMB power spectrum, while ΛCDM does, and various very precise measurements within the solar system also contradict MOND. This was different 30-40 years ago, but since then, as evidence has strongly mounted against MOND, a lot of “shaking out” has already taken place.

MattPalmer1086 1mo ago
Well, MOND is not a cosmological theory or relativistic - there are some different versions that attempt that. MOND itself can't be used to match the CMB spectrum. It has always been a minority position - but it is interesting to see a different perspective. ΛCDM is not without it's own problems. Not least that when new observations contradict it, it just gets tweaked - since we still have no idea what the CDM, if it does exist, actually is. It does not have a great predictive record; it is good at explaining obervations after the fact (the CMB notwithstanding). I am interested to know what the measurements within the solar system are that you refer to. I had thought this was far too small a scale to prove anything about MOND or CDM.
- suuuuuuuu 1mo ago
  > It does not have a great predictive record; it is good at explaining obervations after the fact (the CMB notwithstanding). Can you elaborate on what you mean? LCDM hasn't been "tweaked" since \Lambda was established in the 90s (at least, not for large-scale cosmological observations). The current discrepancies are all at the precision level (<10%) rather than a qualitative O(1) difference. An important (but not dispositive) nuance is that LCDM well explains all observations individually; the percent-level tensions arise only between fits to datasets, meaning unknown systematics remain a viable explanation. The unknown fundamental nature of CDM (as important a problem as it is) seems irrelevant to arguments about LCDM's predictivity (as a cosmological model).
  - MattPalmer1086 1mo ago
    A couple of examples: 1. LCDM predicted hierarchical formation of large galaxies through aggregation. JWST seems to show this is not what happens (large galaxies at early times). I am sure it can be made to work, but it was not a prediction. 2. Constant Lambda - recent obervations seem to show it may be changing (OK - that is more built into the theory rather than being a prediction). By the way, I am not saying LCDM is not massively successful. It can clearly be used to explain a lot of things. I am saying that I am not aware of many things it successfully predicted ahead of observations being made.