Matter consists of a mêlée of elementary particles. There are protons and neutrons, made up of quarks, and many other short-lived massive particles. All atoms consist of protons, neutrons and an accompanying cloud of electrons - then there are electrons, muons and neutrinos, as well as the massless particles - photons.

The very early universe is a unique laboratory for studying the rarest of particles. We see the faded brilliance of the fiery past, and can assemble clues that enable us to trace out the particle content of the beginning of the universe. One hope is to discover particles of dark matter, but this has so far eluded our best efforts.

The transcript and downloadable versions of the lecture are available from the Gresham College website: https://www.gresham.ac.uk/lectures-and-events/elementary-particles-and-their-interactions

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