Question

Observational evidence suggests that the majority of the dark matter is in the form of _______.

a) Neutrinos
b) Exotic particles like axions
c) Black holes
d) None of the above

Answer 1

The majority of dark matter is thought to be exotic particles like axions or neutralinos, known as WIMPs, which have not yet been detected on Earth.

Step-by-step explanation:

Observational evidence suggests that the majority of the dark matter is in the form of exotic particles like axions or neutralinos, which are collectively referred to as WIMPs (weakly interacting massive particles). These particles are hypothesized to be chargeless, only interacting through the weak nuclear force and gravitation, and do not participate in nuclear reactions that produce deuterium. Hence, deuterium abundance cannot limit the quantity of WIMPs in the universe. Sophisticated experiments are ongoing in the search for these hypothetical particles. The dark matter in question cannot be made of more familiar objects like black holes, because they would lead to more X-ray background radiation and other observable effects than we currently detect.