The physics of the very small and the very fast — quanta of light, the structure of the atom, and Einstein's relativity.
Six interactive experiments — all live.
Shine light of different colours on a metal and see why only frequency — not brightness — frees electrons.
Open simulator →Watch electrons jump between energy levels and emit photons of specific colours.
Open simulator →Speed a clock toward light speed and watch time dilation and length contraction set in.
Open simulator →Trap a particle in a box and see the discrete energy levels and standing wavefunctions of quantum mechanics.
Open simulator →Bend starlight into an Einstein ring around the event horizon and watch time slow to a halt at the edge.
Open simulator →Watch hundreds of random quantum coin-flips add up to the perfectly smooth law N = N₀e^(−λt), halving every T½.
Open simulator →