The writer is a science commentatorTrying to spot neutrinos is a bit like trying to catch moonbeams. The subatomic particles permeate the universe but, being near-massless and electrically neutral, they rarely interact with anything. In the seconds it takes you to read this sentence, trillions of these so-called ghost particles will have zipped through your body.
Neutrinos are a new frontier in the quest to stress-test the Standard Model, the basic description of how the universe works. That is because the particles could illuminate one of the most fundamental mysteries in science: why, against expectation, does the universe exist? Two multinational experiments in Japan and the US may furnish answers over the coming decade — answers that could prove as unsettling as Einstein’s challenge to Newton’s law of gravity.
According to the Standard Model, the Big Bang 13.8bn years ago should have created equal amounts of matter and anti-matter, a mirror form of stuff in which every “antiparticle” has the same mass as its corresponding particle but the opposite electrical charge. Each should have cancelled each other out. Instead, here we are — along with other excess matter such as stars and galaxies.