> The key, it seems, is cramming the energy present in microwaves into a very tiny space—the point of contact between the objects in question. In your garden-va

> The key, it seems, is cramming the energy present in microwaves into a very tiny space—the point of contact between the objects in question. In your garden-variety microwave oven, microwaves have a wavelength of about 12.5 cm. But adjoining grapes (which are full of water that can absorb said microwaves) can concentrate the energy within into a region where the two spheres touch, which is no more than a couple millimeters wide. This creates a very strong, very condensed electric field at their interface—a pocket of ammo powerful enough to liberate negatively-charged electrons from, say, the salts naturally present in grapes and other fruits. This is the answer from the article. Not much else is said about the “how” piece This is the paper cited: https://www.pnas.org/doi/full/10.1073/pnas.1818350116 https://www.pnas.org/doi/full/10.1073/pnas.1818350116