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>Dark energy is known to make up 70% of the mass-energy of the universe, whereas black holes are a mere fraction of the ordinary matter, which constitutes less than 5% of the universe. Is there some cosmological constraint that says dark energy compressed into a small volume would exhibit gravitational pull and therefore contribute to our measurements of black hole masses? If not then it feels like this is a weak cou…
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Scientists are also tired of arguing about the reality of evolution, perpetual motion mechanisms, flat earth, a non-plate techtonic earth and maybe other settled matters. Try to get a research fellowship for flat earth or perpetual motion and see just how ruthlessly science cuts down dead ideas. Or maybe now in Florida you can get a flat earth fellowship, the Republicans certainly seem eager to remove the benefits of…
0 - https://www.sciencedirect.com/science/article/pii/S096098222...
>Dark energy is known to make up 70% of the mass-energy of the universe, whereas black holes are a mere fraction of the ordinary matter, which constitutes less than 5% of the universe. Is there some cosmological constraint that says dark energy compressed into a small volume would exhibit gravitational pull and therefore contribute to our measurements of black hole masses? If not then it feels like this is a weak cou…
Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…
Sure. You seem to take issue with this notion. However, this very strategy lead to the discovery of elementary particles (neutrino) and planets (Neptune) in the past. It's how science works.
> Obviously, I don't have an explanation myself, and I understand that we can only work with the evidence we have, but I think it's a sign we need to radically rework our basic assumptions about reality, and not just look for our missing keys...
This is an extremely common opinion among laymen (relevant: https://xkcd.com/1758/). I find it a bit patronizing, because it implies that scientists haven't considered everything under the sun to explain the observations. Please take it from me, who got a PhD in cosmology, that every single person I encountered during my graduate studies was extremely bright, in particular the professors. They have thought of everything a layman can think of a billion times over. The knowledge gap in a field as unintuitive as cosmology between a professor and a layman is basically that of an adult and a toddler.
That's not saying that dark matter or dark energy is beyond any doubt, just that "we need something radically different" is not a very helpful take. You're basically saying "We just need another Einstein", except better data is harder and harder to come by. It's not sufficient anymore to just observe the perihelion shift of mercury. We now need to do things like measure the shapes of billions of galaxies to make any progress, and hope that the billions of galaxies we can observe (there is an upper bound) will yield sufficient precision to even tell two theories apart. We need to build gigantic particle accelerators and build humongous particle detectors in the antarctic to even hope to make some progress.
Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…
That's not how it works.
Many a physics PhD has spent their career trying to come up with better models, including different sorts models of gravity or indeed "to radically rework our basic assumptions about reality,".
Surprisingly, physics professors aren't idiots and have thought of this. It's just that, so far, invisible matter is still the thing that best fits the data compared to the (non-overfitted) modified gravity models people have been able to come up with so far.
Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…
> Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? Sure. You seem to take issue with this notion. However, this very strategy lead to the discovery of elementary particles (neutrino) and planets (Neptune) in the past. It's how science works. > Obviously…
Correct me if I'm wrong (please), but don't we still lack any kind of fundamental definition of what dark energy/matter is other than..."the cause of the difference between what is calculated, and what is observed"? To the point that we aren't even really sure that there is such a "thing" as dark matter (in that it exists in any conventional sense)? From Wikipedia: "Dark matter is a hypothetical form of matter though…
Dark Matter is just a hypotheses to explain our current observations. Future discoveries may back up dark matter, or point towards something different. This is how Science works.