Ultralight axions versus primordial black holes
نویسندگان
چکیده
We reconsider entropy arguments which have been previously argued to support the idea that dark matter constituents are primordial black holes with many solar masses. It has recently shown QCD axions solve strong CP problem may masses [Formula: see text] in extended range text]. Ultralight provide so degrees of freedom their can exceed holes. This suggests ultralight more suited than be matter.
منابع مشابه
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ژورنال
عنوان ژورنال: Modern Physics Letters A
سال: 2021
ISSN: ['1793-6632', '0217-7323']
DOI: https://doi.org/10.1142/s0217732321502412