Or it might be at such high energies, that conventional particle accelerators will never observe it. Sterile neutrinos, axions and quintessence particles might have masses in the PeV range. We were lucky with the Higgs, and the W and Z Bosons, and the top quark.

Dark matter and dark energy might be a phenomenon in the GUT regime, which we will not observe with particle accelerators. We need more information about the Higgs, because it sticks out like a sore thumb of all the other particles. It is our first glimpse into the underlying fabric of the universe, as the Higgs field is non-zero everywhere and a scalar field. No other (known) particle behaves like that. But a future collider is expensive...

just my 2 cents

good plot for a scifi movie: aliens measure a different vacuum value of the Higgs field and discover sub-space communications ;-)

I'm just a layman, but in this[1] paper from 2023 Deur and his collaborators took his model[2] and applied it to the Hubble Tension problem. This paper does mention fitting the CMB well (as I understand it), and the model having no Hubble Tension.

I know his work has been contentious in the past, and that his past work has used multiple models that are not entirely compatible for different problems, weakening his claims.

That said, at least from my armchair it seems like a worthwhile direction to pursue.

[1]: https://arxiv.org/abs/2301.10861

[2]: https://arxiv.org/abs/1709.02481

> If your new hypothesis doesn't even mention the CMB power spectrum

MOND successfully predicted the first peak of the power spectrum. I wonder why everyone focuses so much on LCDM predicting the second peak.

> DM does that, everything else does not.

Whenever someone says DM "does that", it's often after its initial prediction was falsified and the calculation was modified in some way to account for the new observations [1,2]. This has been going on for decades, so that's hardly a ringing endorsement.

I'm not surprised mind you, this is the hallmark of the confirmation bias that's been characteristic of LCDM for decades now.

[1] From Galactic Bars to the Hubble Tension: Weighing Up the Astrophysical Evidence for Milgromian Gravity, https://www.mdpi.com/2073-8994/14/7/1331

[2] Not that MOND is a suitable replacement because it too has its problems. My only point is that this tendency to sweep these inconveniences under the rug as if DM is a compelling and successful theory and saying "nothing else does the job" is disingenuous at best. What you should say is that "nothing does, period, not even our best DM theory", because that's the truth.

The phrase "Dark Matter" literally means we don't know and therefore until something testable is postulated and tested (to be fair i believe some candidates have fallen by the wayside over the years as measurement has improved), it's principally equivalent to plugging in a giant X and giving it properties not unlike Fermi's famous elephant curve fitting comment.

Very true - but the CMB has outlived quite some funerals.

Nobody said it's "true", whatever that even means for a model. The claim is that it's the best anyone has been able to come up with. And not for a lack of trying.

Everybody also acknowledges that there are issue with DM, it's just that every other known model has bigger issues.

It’s not a good objection. It conveniently ignores the actual data.

QM and GR are mutually exclusive: if one is right, the other must be wrong (of course, it's very much still possible that both are wrong). If you use GR to predict the movement and interactions of photons in a medium, it's just wrong. If you use QM to predict the movement of light around a huge body, especially a black hole, it's just wrong. And what's worse, there is no limit or term you can add such that you could say "QM works only for objects up to size X, GR works for objects larger than size Y".

Also, we're nowhere near explaining 99.99999999% of the behaviors we see in the universe. In fact, we're not even able to explain 6% of the things we see in cosmology - as is often explained, dark matter accounts for 27% of all energy in the universe, and dark energy for 68% - and we have no ideas what these actually are, if they exist at all.

> laws of nature "must" be shorter

Coming at this from philosophy of science rather than as a physicist, I feel those quotes around "must".

I think you also recognise how that might be a sort of "fundamentally wrong assumption".

Imagine your words replayed 50 years in the future, not on physics but applied tp the problem of general AI/sentience.

  "The equations that we already have are sufficient to describe human
  thought to 99.9999999% but they are a hodge podge of several
  different theories...."

  "Why on Earth are you looking for a *singular*, unified explanation
  of human experience?"

No detections for abundant stuff over long time frames is not a logical contradiction, but it certainly decreases the plausibility of such a theory relative to alternatives, particularly since we're not expecting any such particle for any other reason (we've tested broad energy ranges). Literally the only evidence we think it exists is incompatibility of our gravitational theory (GR) with observations in a regime where this theory is not as well tested. We already know GR is wrong for other reasons, so the real question is, on balance, which is more plausible? Maybe in the 80s the balance of probability swung one way, but given the unexpectedly successful predictions MOND has made, the repeated unexpected prediction failures of DM, the new energy regime we've probed in the LHC showing nothing, and the repeated, failed DM detection experiments, it's very reasonable that people might conclude that the balance has shifted the other way.

FWIW (which is not much), I was an astrophysicist whose research was Dark Energy, though I arrogate to myself no authority on this topic as frankly a lot of knowledge I used to possess on the topic has been replaced by knowledge of tedious programming APIs (meh...it's a living). My sense was that, perhaps owning to their colorful (colorless?) names, and because they diffused into popular culture more than other equally-important theories in other fields, Dark Matter and Dark Energy were presented to and apprehended by laypeople as "exotic". This invited speculation about these theories and even an urge to overturn them, especially where "exotic" was equated with "tendentious." But, by my lights these theories aren't very exotic. Dark Matter especially seems to me to be very consistent with the history of particle physics. Rutherford first proposed the existence of the neutron in 1920, but it wasn't observed directly until 1932. Pauli first proposed the existence of the neutrino in 1930, but it wasn't observed directly until 1956. Both are forms of "dark matter" and neutrinos were once a candidate for explaining flat rotation curves in galaxies and the "missing mass problem", until they were later excluded by observations of large scale structure. Dark Matter interacts with gravity strongly enough that its effects on astronomical and cosmological scales are pronounced, but it interacts with the other forces weakly enough that so far it hasn't been observed directly. So what?

"the nature of dark matter and dark energy"

I don't know anything about "the nature" of things. That sounds very philosophical to me.

"What are [the properties of Dark Matter and Dark Energy] aside from their effect on the large scale structure of the universe?"

I don't know. I also don't know why you're excluding (in the case of Dark Matter) its gravimetric effect on the large scale structure of the Universe. That seems like a pretty important property to me.

I'm specifically referring to:

> There are- things like flat or hollow earth, antivax and HIV deniers, homeopaths etc. Proponents of all of the above are looking for a grand unifying cosmology. Dark matter and dark energy are confusing and unknown, so people want to just simplify them away.

I think that's pretty uncalled for. To me, positing and exploring alternative views of the universe is a noble and interesting goal, even if the currently accepted answers don't get overturned. The generated ideas might still have other value. Maybe there is a piece of it that's salvageable and can be integrated with other concepts. Or it can inspire future ideas. I think it's pretty uncalled for to lump them in with "flat or hollow earth, antivax and HIV deniers, homeopaths". Do MOND and MOG people make conspiracy YouTube videos about how governments of the world just want you to believe in dark matter and energy to shutter your mind from realizing the truth of their theories? Are they telling people to stop taking chemotherapy and be healed through faith alone instead? Perhaps I'm simply unaware of some nasty behavior, but if not it's pretty rude to lump them in with those other groups.

From my perspective they're engaging in a theoretical pursuit and you're just taking a dump on them.

> If the MOND people and the MOG people keep getting things wrong, they're still free to persevere just as we're free to ignore them.

Are you ignoring them? There are a lot of things I don't pay attention to, MOND/MOG included, but I also don't feel the need to demonize them for getting out of bed in the morning and trying out a new idea. Couldn't you just say, "Interesting concept. I doubt it works out for cosmic background radiation, but would make for a cool Star Trek episode". Or just say nothing?

Why do you have to accuse them of being small-minded, simplistic thinkers who are really just motivated by being too dumb to understand the current meta and not unlike harmful idiots that earnestly believe space is just government propaganda and viruses aren't real?

> people are entitled to

> they're still free to persevere just as we're free to ignore them.

I don't think we were talking about what people should be penalized for by the government, in which case rights and freedoms are primary considerations. We're talking about what things people can do to deserve to be considered unreasonable and be ridiculed, looked down upon, and likely considered harmful to society. I don't think MOND/MOG people qualify.

I don't consider cosmic inflation to be an observation. I consider it theory.