|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'501'711
Articles rated: 2609
20 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
Dark Matter and Naturalness | | Mark P. Hertzberg
; McCullen Sandora
; | | Date: |
26 Aug 2019 | | Abstract: | The Standard Model of particle physics is governed by Poincar’e symmetry,
while all other symmetries, exact or approximate, are essentially dictated by
theoretical consistency with the particle spectrum. On the other hand, many
models of dark matter exist that rely upon the addition of new added global
symmetries in order to stabilize the dark matter particle and/or achieve the
correct abundance. In this work we begin a systematic exploration into truly
natural models of dark matter, organized by only relativity and quantum
mechanics, without the appeal to any additional global symmetries, no
fine-tuning, and no small parameters. We begin by reviewing how singlet dark
sectors based on spin 0 or spin ${1over2}$ should readily decay, while pure
strongly coupled spin 1 models have an overabundance problem. This inevitably
leads us to construct chiral models with spin ${1over2}$ particles charged
under confining spin 1 particles. This leads to stable dark matter candidates
that are analogs of baryons, with a confinement scale that can be naturally
$mathcal{O}(100)$TeV. This leads to the right freeze-out abundance by
annihilating into massless unconfined dark fermions. The minimal model involves
a dark copy of $SU(3) imes SU(2)$ with 1 generation of chiral dark quarks and
leptons. The presence of massless dark leptons can potentially give rise to a
somewhat large value of $Delta N_{ ext{eff}}$ during BBN. In order to not
upset BBN one may either appeal to a large number of heavy degrees of freedom
beyond the Standard Model, or to assume the dark sector has a lower reheat
temperature than the visible sector, which is also natural in this framework.
This reasoning provides a robust set of dark matter models that are entirely
natural. Some are concrete realizations of the nightmare scenario in which dark
matter may be very difficult to detect, which may impact future search
techniques. | | Source: | arXiv, 1908.9841 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER