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寻找暗物质，我们最后的希望在哪里？

暗物质,黑洞,粒子寻找暗物质，我们最后的希望在哪里？

发布时间：2020-12-06加入收藏来源：互联网点击：

A variety of searches for sterile neutrinos have also ruled out this possibility in the relevant mass range. See, e.g., https://arxiv.org/abs/1710.06488 andhttp://iopscience.iop.org/article/10.1088/1742-6596/718/3/032008/pdf

* Exclusions for Axion Dark Matter: Renée Hlozek, David J. E. Marsh, Daniel Grin “Using the Full Power of the Cosmic Microwave Background to Probe Axion Dark Matter” (August 18, 2017, see https://arxiv.org/abs/1708.05681 ).

* Combined direct dark matter detection exclusions.https://arxiv.org/abs/1708.04630 and https://arxiv.org/abs/1707.01632

* Exclusions based on non-detection of annihilations in dwarf galaxies.https://arxiv.org/abs/1708.04858

* Primordial black hole exclusions. https://arxiv.org/abs/1301.4984

* Daniele Gaggero, et al., “Searching for Primordial Black Holes in the radio and X-ray sky” (see https://arxiv.org/abs/1612.00457 ). Abstract:

We model the accretion of gas on to a population of massive primordial black holes in the Milky Way, and compare the predicted radio and X-ray emission with observational data. We show that under conservative assumptions on the accretion process, the possibility that O(10) M⊙ primordial black holes can account for all of the dark matter in the Milky Way is excluded at 4σ by a comparison with the VLA radio catalog at 1.4 GHz, and at more than 5σ by a comparison with the NuSTAR X-ray catalog (10 – 40 keV). We also propose a new strategy to identify such a population of primordial black holes with more sensitive future radio and X-ray surveys.

* Tight Warm Dark Matter parameter exclusions,https://arxiv.org/pdf/1704.01832.pdf

* More Warm Dark Matter parameters exclusions: Simon Birrer, Adam Amara, and Alexandre Refregier, “Lensing substructure quantification in RXJ1131-1231: A 2 keV lower bound on dark matter thermal relict mass” (January 31, 2017, seehttps://arxiv.org/abs/1702.00009 ).

We study the substructure content of the strong gravitational lens RXJ1131-1231through a forward modelling approach that relies on generating an extensive suite of realistic simulations. The statistics of the substructure population of halos depends on the properties of dark matter. We use a merger tree prescription that allows us to stochastically generate substructure populations whose properties depend on the dark matter particle mass. These synthetic halos are then used as lenses to produce realistic mock images that have the same features, e.g. luminous arcs, quasar positions, instrumental noise and PSF, as the data. By analyzing the data and the simulations in the same way, we are able to constrain models of dark matter statistically using Approximate Bayesian Computing (ABC) techniques. This method relies on constructing summary statistics and distance measures that are sensitive to the signal being targeted. We find that using the HST data for \RXJ we are able to rule out a warm dark matter thermal relict mass below 2 keV at the 2 sigma confidence level.

* Paolo Salucci and Nicola Turini, “Evidences for Collisional Dark Matter In Galaxies?” (July 4, 2017, see https://arxiv.org/abs/1707.01059 ). Abstract:

The more we go deep into the knowledge of the dark component which embeds the stellar component of galaxies, the more we realize the profound interconnection between them. We show that the scaling laws among the structural properties of the dark and luminous matter in galaxies are too complex to derive from two inert components that just share the same gravitational field. In this paper we review the 30 years old paradigm of collisionless dark matter in galaxies. We found that their dynamical properties show strong indications that the dark and luminous components have interacted in a more direct way over a Hubble Time. The proofs for this are the presence of central cored regions with constant DM density in which their size is related with the disk length scales. Moreover we find that the quantity ρDM(r,L,RD)ρ⋆(r,L,RD) shows, in all objects, peculiarities very hardly explained in a collisionless DM scenario.

* Dark matter distributions have to closely track baryon distributions, even though there is no viable mechanism to do so: Edo van Uitert, et al., “Halo ellipticity of GAMA galaxy groups from KiDS weak lensing” (October 13, 2016, seehttps://arxiv.org/abs/1610.04226 ).

* One of the more successful recent efforts to reproduce the baryonic Tully-Fischer relation with CDM models is L.V. Sales, et al., “The low-mass end of the baryonic Tully-Fisher relation” (February 5, 2016, seehttps://arxiv.org/abs/1602.02155 ). It explains:

[T]he literature is littered with failed attempts to reproduce the Tully-Fisher relation in a cold dark matter-dominated universe. Direct galaxy formation simulations, for example, have for many years consistently produced galaxies so massive and compact that their rotation curves were steeply declining and, generally, a poor match to observation. Even semi-analytic models, where galaxy masses and sizes can be adjusted to match observation, have had difficulty reproducing the Tully-Fisher relation, typically predicting velocities at given mass that are significantly higher than observed unless somewhat arbitrary adjustments are made to the response of the dark halo.

The paper manages to simulate the Tully-Fisher relation only with a model that has sixteen parameters carefully “calibrated to match the observed galaxy stellar mass function and the sizes of galaxies at z = 0” and “chosen to resemble the surroundings of the Local Group of Galaxies”, however, and still struggles to reproduce the one parameter fits of the MOND toy-model from three decades ago. Any data set can be described by almost any model so long as it has enough adjustable parameters.

* Dark matter can’t explain bulge formation in galaxies: Alyson M. Brooks, Charlotte R. Christensen, “Bulge Formation via Mergers in Cosmological Simulations” (12 Nov 2015, see https://arxiv.org/abs/1511.04095 ).

回答于 2019-09-11 08:43:50

寻找暗物质，我们最后的希望在人自身的探测功能。这是我们可以控制的唯一的高维度探测仪，前面各式各样的探测器，以低维度的观测，探讨高维度存在的问题，自然劳而无功，毫无结果。用人自身试一试就可以了。上面国内外物理专家的研究，已经看到了曙光就在前面。

回答于 2019-09-11 08:43:50

黑洞显然是暗物质，时空发现引力波，显然时空也是物质的，但很奇怪引力波以光速传播，说明时空中的物质又是没有质量的，它显然是一种波色子。它到底是什？它应该是最小的粒子，数量庞大，且均匀充斥整个宇宙，因它的束缚，整个时空所有物质、粒子以相同的速度运行（光速）。它最小，但数量庞大，它才是维系我们宇宙不被撕裂主角。

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