This experiment is searching for dark matter that must have properties in a part of the dark matter parameter space that direct dark matter detection experiments and particle collider tests have already ruled out by a dozen orders of magnitude or more. It is also basically ruled out by the LAT collaboration.
It is arguably one of the biggest wastes of time in the astronomy community right now. I would never have voted to fund it, if I were sitting on a committee considering the proposal.
Numerous observations confirm the existence of dark matter (DM) at astrophysical and cosmological scales. Theory and simulations of galaxy formation predict that DM should cluster on small scales in bound structures called sub-halos or DM clumps. While the most massive DM sub-halos host baryonic matter, less massive, unpopulated sub-halos could be abundant in the Milky Way (MW), as well and yield high-energy gamma rays as final products of DM annihilation. Recently, it has been highlighted that the brightest halos should also have a sizeable extension in the sky. In this study, we examine the prospects offered by the Cherenkov Telescope Array Observatory (CTAO), a next-generation gamma-ray instrument, for detecting and characterizing such objects. Previous studies have primarily focused on high-latitude observations; here, we assess the potential impact of the CTAO's Galactic Plane Survey, which will provide unprecedentedly deep survey data for the inner five degrees of the Galactic plane. Our modeling accounts for tidal effects on the sub-halo population, examining the conditions under which DM sub-halos can be detected and distinguished from conventional astrophysical sources. We find that regions a few degrees above or below the Galactic plane offer the highest likelihood for DM sub-halo detection. For an individual sub-halo -- the brightest from among various realizations of the MW subhalo population -- we find that detection at the 5σ level is achievable for an annihilation cross section of ⟨σv⟩∼3×10^−25 cm^3/s for TeV-scale DM annihilating into bb¯. For a full population study, depending on the distribution and luminosity model of Galactic sub-halos, yet unconstrained cross sections in the range ⟨σv⟩∼10^−23−10^−22 cm^3/s for TeV DM candidates are necessary for the brightest sub-halos to be detected.
Christopher Eckner, et al., "Detecting dark matter sub-halos in the Galactic plane with the Cherenkov Telescope Array Observatory" arXiv:2501.09789 (January 16, 2025).
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Reference: “Particle exchange statistics beyond fermions and bosons” by Zhiyuan Wang, and Kaden R. A. Hazzard, 8 January 2025, Nature.
DOI: 10.1038/s41586-024-08262-7
"It is commonly believed that there are only two types of particle exchange statistics in quantum mechanics, fermions and bosons, with the exception of anyons in two dimensions1,2,3,4,5. In principle, a second exception known as parastatistics, which extends outside two dimensions, has been considered6 but was believed to be physically equivalent to fermions and bosons7,8,9. Here we show that non-trivial parastatistics inequivalent to either fermions or bosons can exist in physical systems. These new types of identical particle obey generalized exclusion principles, leading to exotic free-particle thermodynamics distinct from any system of free fermions and bosons. We formulate our theory by developing a second quantization of paraparticles that naturally includes exactly solvable non-interacting theories and incorporates physical constraints such as locality. We then construct a family of exactly solvable quantum spin models in one and two dimensions, in which free paraparticles emerge as quasiparticle excitations, and their exchange statistics can be physically observed and are notably distinct from fermions and bosons. This demonstrates the possibility of a new type of quasiparticle in condensed matter systems and—more speculatively—the potential for previously unconsidered types of elementary particle."
Notably, the proof is limited to 1 and 2 dimensions, even though the article suggests that it should be generalizable to a greater number of dimensions. It is primarily relevant to condensed matter physical systems that are effectively one or two dimensional.
They are absolutely not preons. True "paraparticles" and "anyons" are not actual particles and thus can't be dark matter. They are emergent phenomena that arise in many body systems https://en.wikipedia.org/wiki/Quasiparticle.
maybe space-time and dark energy are emergent phenomena that arise in many body systems eg Grigory E. Volovik
Gravity through the prism of condensed matter physics
Authors: G. E. Volovik
Abstract: In the paper "Life, the Universe, and everything--42 fundamental questions", Roland Allen and Suzy Lidström presented personal selection of the fundamental questions. Here, based on the condensed matter experience, we suggest the answers to some questions concerning the vacuum energy, black hole entropy and the origin of gravity. In condensed matter we know both the many-body phenomena emerging on the macroscopic level and the microscopic (atomic) physics, which generates this emergence. It appears that the same macroscopic phenomenon may be generated by essentially different microscopic backgrounds. This points to various possible directions in study of the deep quantum vacuum of our Universe
From Landau two-fluid model to de Sitter Universe
G.E. Volovik
The condensed matter analogs are useful for consideration of the phenomena related to the quantum vacuum. This is because in condensed matter we know physics both in the infrared and in the ultraviolet limits, while in particle physics and gravity the physics at trans-Planckian scale is unknown. One of the corner stones of the connections between the non-relativistic condensed matter and the modern relativistic theories is the two-fluid hydrodynamics of superfluid helium. The dynamics and thermodynamics of the de Sitter state of the expansion of the Universe bear some features of the multi-fluid system. There are actually three components: the quantum vacuum, the gravitational component and relativistic matter. The expanding de Sitter vacuum serves as the thermal bath with local temperature, which is twice the Gibbons-Hawking temperature related to the cosmological horizon. This local temperature leads to the heating of matter component and the gravitational component. The latter behaves as Zel'dovich stiff matter and represents the dark matter. In equilibrium and in the absence of the conventional matter the positive partial pressure of dark matter compensates the negative partial pressure of quantum vacuum. That is why in the full equilibrium the total pressure is zero. This is similar to the superfluid and normal components in superfluids, which together produce the zero pressure of the liquid in the absence of environment. If one assumes that in dynamics, the gravitational dark matter behaves as the real Zel'dovich stiff matter, one obtains that both components experience the power law decay due to the energy exchange between these components. Then it follows that their values at present time have the correct order of magnitude. We also consider the other problems through the prism of condensed matter physics, including the black holes and Planck constant.
Comments: 24 pages, no figures. arXiv admin note: text overlap with arXiv:2307.00860, draft of the paper for collection of papers dedicated to 60 years of Landau Institute
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