Vaikra-Leviticus 14:35-36 (Metzora)
35. and the one to whom the house belongs comes and tells the kohen, saying, “Something like a plague has appeared to me in the house,”
36. the kohen shall order that they clear out the house, before the kohen comes to look at the lesion, so that everything in the house should not become unclean. After this, the kohen shall come to look at the house.
Let us analyze these two verses from the point of view of quantum mechanics. An owner of the house sees a suspicious lesion on the house that looks like tzara’as and calls a cohen (priest) to inspect the house. There are two possible states of the house: Pure (no tzara’as) or Impure (contaminated by tzara’as). At this moment, before the cohen inspects the house and collapses the wavefunction, the house is in a state of linear superposition of two states: Pure and Impure, something like ½ Pure + ½ Impure. Only a cohen can collapse the wavefunction of the house and declare it pure or impure. The cohen, therefore, is a participating observer in quantum-mechanical sense. When the cohen looks at the house, he collapses its wavefunction and house will be pronounced either pure or impure. All pots and furniture contained in the house are entangled with the house. If the house will be pronounced impure, all that is entangled with it will automatically become impure as well.
This is very much analogous to the infamous Schrödinger cat entangled with radioactive atom inside the box and suspended in the blurred state of superposition of being alive and dead. Here, instead of the box, we have a house; and instead of a cat, we have kelim (furniture, pens and pots) in the house entangled with it. As the Schrödinger cat, kelim are suspended in blurred state of superposition of pure and impure. When an observer looks inside the box, he or she will collapse the cat’s wavefunction and will find the cat either dead or alive. Similarly, when a cohen looks on the house, he will collapse the wavefunction of the house and the kelim inside, which will all become pure or impure. Should we call them Schrödinger pots?
Should the house be declared impure by the cohen, some of the objects inside the house, such as earth-ware, could no longer be purified and would have to be broken. Not wishing to inflict an unnecessary financial loss to the homeowner, the cohen instructs him to empty out the house so that kelim (furniture and pots) will no longer be entangled with the house and will not become impure together with the house, when he collapses the wavefunction.
Arguably, this is one of the earliest practical applications of the laws of quantum mechanics in biblical times.