Stepping back from any solution, here are some observations about dark matter phenomena and dark energy phenomena.
1. Dark matter phenomena appear to be fully determined from the distribution of ordinary matter to the limits of experimental precision and our ability to calculate theoretically expected relationships.
2. Dark matter phenomena are only discernible in extremely weak gravitational fields; dynamics in stronger gravitational field can be fully described with Newtonian gravity with general relativity adjustments near very large compact masses and for very fast moving objects.
3. The magnitude of dark energy phenomena at any one place is much weaker than the magnitude of dark matter phenomena.
4. The form of a gravitational pull that would produce flat rotation curves in spiral galaxies is consistent with dimensional reduction from a sphere to a disk of gravitational pull.
5. Alignment of celestial bodies in a plane is expected when there is dimensional reduction of gravitational pull.
6. The more spherically symmetric an agglomeration of matter is the weaker the apparent dark matter phenomena that it exhibits.
7. Galactic clusters exhibit a greater magnitude of dark matter phenomena than galaxies do.
8. Some ultra-diffuse galaxies show an immense amount of dark matter-like effects, while others show almost none. Those that exhibit almost none are in locations where an external field effect is one possible explanation and tidal stripping of dark mater is another. In general, there is strong statistical evidence for an external field effect.
9. There is no credible evidence for the existence of, and there are no credible theoretical predictions to suggest, that there are any hadrons other than protons and bound neutrons which are stable for more than even a microsecond.
10. If dark matter particles of 1 GeV mass to 1000 GeV mass exist, they have a cross-section of interaction with ordinary matter that is millions to billions of times weaker than neutrinos which interact only via the weak force and gravity. All known fundamental particles have the same magnitude of weak force charge. The mass range at which interactions with ordinary matter are weaker than neutrinos extends below 1 GeV.
11. If dark matter particles of 1000 to 100,000 GeV exist, they have a cross-section of interaction with ordinary matter that is weaker than any force other than the weak force.
12. Dark matter particles with masses of asteroid scale or larger do not account for a significant share of dark matter phenomena.
13. No black holes with masses less than what would be produced by a stellar collapse have been observed. Primordial black holes cannot be a sole explanation of dark matter phenomena.
14. Parameter fitting for self-interacting dark matter theories to a Yukawa force model produce an interaction strength on the same order of magnitude as electromagnetism but with a limited range suggestive of a force carrying boson with a mass on the order of a pion.
15. Inferred dark matter particle halo shapes rarely correspond to an NFW distribution which is what would be expected from a collisionless particle with a mass too large to have significant quantum effects.
16. Galaxies form significantly earlier than would be predicted in a cold dark matter particle cosmology, but this observation is consistent with many gravitational explanations of dark matter phenomena.
17. It is possible in multiple ways to reproduce the cosmic background radiation amplitude peaks with a gravitational as opposed to a dark matter explanation.
18. The aggregate magnitude of dark matter phenomena in the universe is about half of the aggregate magnitude of dark energy phenomena in the universe.
19. Dark energy phenomena are only observed at scales of at least intergalactic distances.
20. General relativity with a cosmological constant (one form of dark energy) does not globally conserve mass-energy.
21. There is strong observational evidence that if dark matter particles exist they are stable on the time frame of the age of the universe, or are created and destroyed in indiscernible interaction that are in near perfect equilibrium.
22. There is evidence from simulations that neither collisionless warm dark matter, nor self-interacting dark matter that has no interactions with ordinary matter can explain observed dark matter phenomena.
23. Gravitational lensing of light is consistent with general relativity or a massless graviton, but is inconsistent with a massive graviton.
24. Gravitational waves travel at a speed consistent with the speed of light and limited to a tiny deviation from the speed of light.
25. There is no credible evidence of sterile neutrinos that oscillate with active neutrinos.
26. Cosmology evidence strongly suggests that there are only three flavors of neutrinos that are consistent with the cosmology definition of a neutrino.
27. Collisions between galaxies and galaxy clusters happen more often and at higher velocities than predicted by a LambdaCDM model.
28. The radial acceleration relation holds for galaxies of all observed sizes (except for the small number of "no dark matter" ultra-diffuse galaxies where an external field effect could be present).
29. No mechanism sufficient to produce "feedback" effects necessary to make the LambdaCDM model work in simulations has been observed in specific instance.
30. There are strong, but not conclusive hints that dark energy has not been constant over time and that the Hubble constant has not, in fact, been constant over time. The Hubble constant as estimated from the cosmic background radiation pattern appears smaller then than it is in recent billions of years from multiple kinds of observations.
31. Efforts to detect axions or axion-like particles have so far failed to see any, and the "strong CP problem" has multiple proposed solutions that do not rely on axions.
32. There is no positive experimental evidence of supersymmetry.
33. There is no positive evidence of any non-Standard Model Higgs boson.
34. Hot dark matter particles (e.g. thermal freeze out dark matter with masses on the order of neutrino masses) are ruled out observationally.
7 comments:
21. There is strong observational evidence that if dark matter particles exist they are stable on the time frame of the age of the universe,
Dark matter as Planck relics?
or are created and destroyed in indiscernible interaction that are in near perfect equilibrium.
X17?
Definitely not X17 which if it exists is expected to have a mean lifetime of a fraction of a second.
Planck relics? Really?
i was thinking x17 created and destroyed in indiscernible interaction that are in near perfect equilibrium
4. The form of a gravitational pull that would produce flat rotation curves in spiral galaxies is consistent with dimensional reduction from a sphere to a disk of gravitational pull.
dark energy effects ?
The X17 is just somebody trying to overcome their bad analysis with a new particle. It isn't real. Follow experiments will confirm this fact.
Dark energy effects are far too weak to explain dark matter phenomena.
The hypothetical X17 particle is proposed to have a mean lifetime of 10^-14 seconds after which it purportedly decays into an electron and positron pair (it purportedly has spin-1 and a neutral electromagnetic charge).
At the speed of light it could go no further than 3*10^-6 meters and since it is proposed to have mass it can't go that fast, so its actual effective range would have to be smaller. Analyzing the range of a 17 MeV Yukawa force carrier you get a range of closer to 6 fm, which is way to small for it to be involved in dark matter.
The processes with which it purports to be associated are not ones that could be in equilibrium:
"The particle has been proposed to explain wide angles observed in the trajectory paths of particles produced during a nuclear transition of beryllium-8 atoms and in stable helium atoms."
"Feng et al. (2016) proposed that a "protophobic" X boson, with a mass of 16.7 MeV, suppressed couplings to protons relative to neutrons and electrons at femtometer range."
"As of December 2019, the ATOMKI paper describing the particle has not been peer reviewed and should therefore be considered preliminary. In late 2019, a follow-up paper was published in Acta Physica Polonica B.[1] Efforts by CERN and other groups to independently detect the particle have been unsuccessful so far. The ATOMKI group had claimed to find various other new particles earlier in 2016 but abandoned these claims later, without an explanation of what caused the spurious signals. The group has also been accused of cherry-picking results that support new particles while discarding null results."
See https://en.wikipedia.org/wiki/X17_particle
The claim that it could have anything to do with dark matter phenomena is simply irresponsible hype with no plausible scientific basis even if the claimed particle really existed.
Of course, the muon g-2 anomaly which it has been proposed to shed light upon doesn't actually exist and is the product of a flawed SM prediction for muon g-2 so that justification for it is also a fail.
The claim that it could have anything to do with dark matter phenomena is simply irresponsible hype with no plausible scientific basis even if the claimed particle really existed.
it could be part of a hidden sector with other particles
Dark energy effects are far too weak to explain dark matter phenomena.
Dark energy effects + gravity in 2D might be MOND
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