The dark matter halo around our galaxy should exhibit different interaction probabilities as the Earth orbits the Sun, varying our motion through the dark matter in our galaxy. Image credit: ESO / L. Calçada.

The foolish optimism of thinking dark matter is about to be detected

Just because we know it’s real doesn’t mean it’s easy to create in a lab.

“For me the best answer is not in words but in measurements.” -Elena Aprile

Atoms, molecules, human beings, the Earth, the Sun, stars, galaxies, gas, dust and plasma in the Universe all have something in common: they’re all made of the same fundamental particles. Yet if you break everything we know, see and perceive down into its smallest constituents, you can only explain about 15% of the total mass in the Universe. Without emitting or absorbing light, 85% of the Universe is mysterious, visible only through its gravitational effects on the luminous, interacting matter we know. This dark matter has an overwhelming suite of astrophysical evidence for it, but seeing something from afar isn’t the same as creating, detecting and analyzing it in a lab for ourselves. Despite the fact that there are a great many experiments searching for dark matter, it would take a foolish level of optimism to expect any of them to be successful anytime soon.

Dark matter/nucleon scattering would produce a specific signal, but there are many mundane, background contributions that could give a similar result. This will show up in Germanium, liquid XENON and liquid ARGON detectors. Image credit: Dark Matter Overview: Collider, Direct and Indirect Detection Searches — Queiroz, Farinaldo S. arXiv:1605.08788 [hep-ph].

• Direct creation of dark matter particles via…