Sixty Symbols

Sixty Symbols began in 2009 as a project between physicists at the University of Nottingham and video journalist Brady Haran. The original plan was to explain sixty symbols used in physics and astronomy. The channel has long since passed that number and now covers hundreds of topics.

The videos are informal conversations with working researchers. Professors talk through an idea at a whiteboard or on brown paper, often reacting to recent news such as Nobel prizes, new telescope images or claims about artificial intelligence. The tone is relaxed, but the people explaining are experts in their fields. Teachers often use the videos to extend A level physics lessons.

Some highlights include:

A careful explanation, with the equations shown, of why nothing can travel faster than light.

Astronomers discuss the first image of a black hole and what it actually shows.

A look at the attosecond laser pulses behind the 2023 Nobel Prize in Physics and why they matter.

The channel has over 880,000 subscribers and still posts new videos regularly.

Physics sits underneath every branch of engineering. Sixty Symbols is a good way to hear how real scientists think, argue and check their reasoning. It suits students weighing up physics, astrophysics or engineering at university, and anyone who wants more depth than a textbook gives. The videos also show that scientists disagree, change their minds and enjoy a good debate.