What would happen if a microwave, microwaved a microwave microwaving a metal spoon?
Great idea, but unfortunately it would not open a portal into an alternate universe. You’d probably only get one or two broken microwave ovens. Not as fun, but more realistic. The metal cabinet of the microwave oven on the inside would act like a Faraday cage, completely isolating everything on the inside of the inner oven from the outer oven, and everything outside of the inner oven from the inner oven. The inner oven would only be affected by the metal spoon, which would soon cause an equipment malfunction after a period of sparks. On our oven, the repair bill was over $100. The metal cabinet of the inner microwave oven would probably spark like most metals (the Faraday cage effect hides everything more than a few microns inside that cabinet, but not the cabinet itself), soon causing an equipment malfunction of the outer microwave oven. Now the repair bill is doubled, and still no portal.
