Mystery of dark matter in Halloween spotlight

Researchers are taking part in a series of events on Halloween to celebrate Dark Matter Day – highlighting research into a mysterious substance that surrounds us, but is little understood.

As part of Dark Matter Day activities on 31 October, scientists will engage with policymakers and the public at events around the world, many of which are hosted on social media.

Professor Alex Murphy from the School of Physics and Astronomy will meet politicians at Westminster and give a public talk as part of Dark Matter Day events.

Fundamental science

The search for dark matter represents one of the scientific arena’s greatest challenges, with researchers at Edinburgh at the forefront of work in the field.

Directly observing dark matter and learning more about it could help explain fundamental physics such as how galaxies are formed, and the gravity that holds them together.

Studies to date suggest dark matter and its counterpart, dark energy, together account for about 95 per cent of the Universe. Ordinary matter – including the planets and stars – make up the remainder.

Experimental efforts

Astronomers have found evidence of dark matter through its effect on gravity in distant galaxies, and physicists are carrying out sophisticated experiments to directly detect particles that demonstrate its existence.

Scientists at Edinburgh are involved in an international collaboration, known as Lux-Zeplin, which is searching for elusive dark matter particles.

Particle search

These weakly interacting massive particles, or WIMPS, do not absorb light and react only rarely with regular matter.

The team is searching for WIMPS using a large detector filled with unreactive liquid xenon. Sensitive light meters are primed to detect the impact of a WIMP on a xenon particle.

The experiment is housed in a lab deep underground to prevent interference from background radiation.

Lux-Zeplin is one of many teams around the world searching for direct observations of dark matter.

Pinpointing dark matter would enable a new avenue of research into the material that accounts for much of our Universe, and give unprecedented insight into fundamental aspects of physics.

Professor Alex MurphySchool of Physics and Astronomy