From Edmund Marr
Michael Brooks mentions the double-slit experiment, saying that as long as no one is watching, the photon exists in two places at once. When discussing Markus Arndt’s application, which showed that a carbon-70 molecule can also go through two slits at once, he states that: “though these ball-shaped molecules aren’t quite as substantial as cats, they can nonetheless be seen through a microscope” (26 June, p 34). How many cat flaps did Schrödinger have? If he wasn’t watching, which flap did the cat use?
Chippenham, Wiltshire, UK
