Universe's Missing Pieces Unveiled

Scientists Review Dark Matter's Origins and Elusive Hunt

New research explores how dark matter, the universe's invisible scaffolding, might be created and finally found.

For decades, scientists have puzzled over dark matter, a mysterious substance that doesn't interact with light, making it truly invisible. This new review gathers existing knowledge on this cosmic enigma. Researchers explored how dark matter could have been formed and the sophisticated ways scientists are trying to detect it.

Potential Origins and Candidates

The study looked at how dark matter might have been created from dark energy during the universe's fiery early moments, a process called "cosmological phase transitions" (moments in the very early universe where conditions changed dramatically, like water turning to ice).

It also investigated exotic particles called "sterile neutrinos" (hypothetical, elusive subatomic particles that interact even less with normal matter than regular neutrinos) as possible dark matter candidates. The study did not involve new experiments but reviewed many existing findings.

Where Does Dark Matter Fit?

Previous observations of the Cosmic Microwave Background Radiation (CMBR) (faint glow left over from the Big Bang) show that the universe's total density is estimated to be 1.0023. Of this:

Roughly 73 percent is dark energy.
Only about 4 percent is the ordinary matter that makes up stars, planets, and us.
The remaining 23 percent is dark matter.

The review suggests that during the Electroweak Phase Transition (EWPT), dark matter particles might have formed with masses from a few GeV to 140 GeV. During the Quantum Chromodynamics Phase Transition (QCDPT), they could be heavier, ranging from 0.5 to 3.5 TeV. To give a sense of scale, a proton has a mass of about 1 GeV.

"Dark matter is a significant component of the universe, making up approximately 23% of its density."

This unseen stuff holds galaxies together, acting like invisible glue in the cosmic web. Without it, galaxies would likely fly apart.

The Hunt for Dark Matter

Experiments like LUX and PandaX-II, which use large detectors filled with noble gases like xenon, are actively hunting for dark matter by looking for tiny interactions it might have with normal matter.

Scientists still face big challenges in finding dark matter. Its exact makeup remains unknown, and current detection methods are indirect. Future research will need more theoretical ideas and new experimental approaches to solve this cosmic riddle.

Dark matter remains one of the universe's greatest mysteries, silently shaping the cosmos around us.

Reference:

Kisslinger, L. S., & Das, D. (2019). Review of Dark Matter. arXiv preprint arXiv:1908.00612.