Physicists working to understand how and why matter came about

Neutrinos, subatomic remnants of the early universe, are high-energy particles that pass at nearly the speed of light through everything -- our planet, our bodies -- while rarely interacting with other matter. Most of them were born in the beginning, nearly 14 billion years ago, though more are continually made in the nuclear reactions of stars, in human-built nuclear reactors and in particle accelerators used for experimentation.

These ghostly particles are of intense interest to physicists because they may be a key player in how the universe came to be; how, in the first moments after the Big Bang, matter managed to annihilate antimatter, allowing a universe of particles to coalesce and form atoms, molecules, elements and compounds, the matter that became and becomes galaxies, black holes, planets and -- on one planet at least -- life.