[strong-cp] https://en.wikipedia.org/wiki/Strong_CP_problem [chiral] https://arxiv.org/abs/2412.02024
Adjust the theory to make it darker, lighter and more nebulous.
The end station of dark matter is that "we know it's real because computer models but due to a fluke there's no dark matter in the solar system so we can't detect it".
- galaxy rotation curves
- galaxy cluster dynamics
- gravitational lensing
- the Cosmic Microwave Background radiation
- large-scale structure
- Baryon Acoustic Oscillations
- X-ray emission in galaxy clusters
- galaxy cluster collisions
- mass-to-light ratios
That's a tall order for any competing theories. They're welcome to try, of course, but so far none have succeeded.
I have gotten skeptical of these “could be amazing” researches - I suspect success in academia is PR and funding as much as actual good ideas and it’s hard for an outsider to know the difference (or care?).
That is kind of just how the job works unfortunately.
Unless the way research funding changes (I don't know how) you need money to do research and to get that money you need to be good at selling an idea.
Why is it so hard for people to believe that there are some particles that are not interacting with electromagnetism that we haven't detected directly yet? It's not even a precedent, the neutrino is just like that.
I guess the name "dark" matter was a mistake because it implies something weird, when in fact it just means whatever this is, doesn't have electric (or chromo) charge.
But we are not very well educated so yeah, they will doubt it for no good reason other than "it doesn't feel right"
The orbit of planets in our solar system have hinted at missing matter several times -- one time it lead to the discovery of a new planet (Uranus or Neptune, IIRC); one time it lead to the discovery of General Relativity.
Until we either detect dark matter/energy, or develop a theory that accurately predicts the behaviour we're attributing to dark matter we cannot say one way or the other which is the correct approach.
It could also be that we are not accurately modelling EM/SR/GR effects at a large scale, such as how they are warped by the different stars orbiting the arms of the galaxies. Or that when we extend QED/QCD to accelerating reference frames (general relativity) that dark matter won't be needed, just like how QED was formulated by extending electromagnetism/QM to special relativity (non-accelerating reference frames).
Yes, while we sometimes do pursue scientific inquiry for its practical application to the betterment of humanity, we also recognize the value of scientific inquiry simply for expanding the endowment of human knowledge about the world. That is an "innate good". Moreover, if history is any guide, it's sometimes or even often difficult to predict what practical applications will or won't emerge from any given scientific endeavor. In the case of Dark Matter, it may not be exactly the case that we will ever directly manipulate it in any scientific application. However, it may be the case that by grappling with Dark Matter we will refine and deepen our understanding of the fundamental laws of nature, and that will unlock future practical applications. Then there is the topic of "human capital": training people to be scientists trains cadres of people with strong skills in science, math, engineering, and computer science, which is an investment in that human capital. Often, they're well-equipped to go on to fruitful careers outside of their initial field of inquiry, producing innovations that benefit humanity. Finally, if it's a matter of cost, many people feel that the societal cost (e.g. federal expenditures on science) are puny compared to other things which I need not name here. Consequently, "basic science" which includes fundamental physics and the study of Dark Matter, is always a great investment for society.
Or something like that...that's my understanding of how that argument goes. Make of it what you will.
Superconductivity is absurd magic and took impossibly low temperatures until they weren't impossible, and now it's driving MRIs, massively improving medical research, and the realm of usability is constantly expanding. Absolute zero was known reasonably accurately for over 100 years before liquid helium was achieved, and superconductivity came only three years after.
It's the kind of thing you can frequently only judge accurately in retrospect.
My guess? If we figure out how to detect dark matter we can get closer to figuring out how to interact with it (other than through the very very very weak gravitational force). Or maybe we figure out that it was a spinning universal frame or something that gives us a better Standard Model.
If, however, we figure out how to interact with it and can harness any potential energy from it, then by definition we won't see any interference in the electromagnetic forces. That would be incredible, that would be as good as having readily available superconductors.
"It's of no use whatsoever. This is just an experiment that proves Maestro Maxwell was right—we just have these mysterious electromagnetic waves that we cannot see with the naked eye. But they are there." -- Heinrich HertzIs my theory even _possible_ here, or am I missing something. Really fundamental?
> FWIU this Superfluid Quantum Gravity rejects dark matter and/or negative mass in favor of supervaucuous supervacuum, but I don't think it attempts to predict other phases and interactions like Dark fluid theory?
From https://news.ycombinator.com/item?id=42371946 :
> Dark fluid: https://en.wikipedia.org/wiki/Dark_fluid :
>> Dark fluid goes beyond dark matter and dark energy in that it predicts a continuous range of attractive and repulsive qualities under various matter density cases. Indeed, special cases of various other gravitational theories are reproduced by dark fluid, e.g. inflation, quintessence, k-essence, f(R), Generalized Einstein-Aether f(K), MOND, TeVeS, BSTV, etc. Dark fluid theory also suggests new models, such as a certain f(K+R) model that suggests interesting corrections to MOND that depend on redshift and density
pavel_lishin•4h ago
Can someone explain this using an analogy that makes sense?
pyinstallwoes•4h ago
slow_typist•4h ago
evanb•4h ago
But sympathetic response, or resonance, is how this device would work---just like a radio. Axions couple to electromagnetism; by listening in on different frequencies we can see if there is any "cosmic signal being broadcast" (meaning: axions suffusing the galaxy); the frequency of the signal corresponds to the mass of the axion.
In that sense, the search for resonances is a classic approach in particle physics; various particles were discovered by finding increased signals at particular collision energies. What's different here is that it isn't a resonance in a collision cross-section but an axion --> electromagnetism conversion.
staplung•1h ago