Illustration of Parity violation

1956 Parity violation

The book of science

Tom Sharp

Tsung-Dao Lee, Chen-Ning Yang physics Illustration of Parity violation

Parity violation

Everyone thought antimatter was to matter as matter is to a mirror. If matter spins right then antimatter spins left. But experiments violated expectations. It turned out the weak force violated mirror symmetry. Only the left-handed components of matter and right-handed components of antimatter participate in weak interactions.

This might be why

We live in a universe of matter instead of a universe of antimatter. Masses must warp space or they would not congregate. Light must travel at a constant rate, not to be exceeded by anything. Energy must equal mass times the square of the speed of light. If it were not true, then we wouldn’t be here to suppose it otherwise.

Camera violation

When I turn to my right looking in a mirror, I’m turning the same direction, which if you were facing me, would be to your left. Turn your head to the right to take a selfie with the camera on your phone. On the screen of your phone you’re looking in the same direction. In the photo, you will be looking in the other direction.

The discovery of parity violation solved a problem with the decay of charged strange mesons in quantum field theory. Experimental verification came only after Lee suggested that researchers look for it. The effect had been noticed in 1928 but it was ignored because there was no theoretical support.

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