You're falling into the very common trap of assuming that "energy" is some kind of substance (like movies/series tend to depict it as for practical reasons), wh

You're falling into the very common trap of assuming that "energy" is some kind of substance (like movies/series tend to depict it as for practical reasons), when really it is a mathematical property of a physical object. Like other similar properties (such as spin, momentum and angular momentum), energy is relevant because fundamental symmetries of the universe require it to be constant. Therefore "losing energy" in one part of a physical system (such as the electron) is only possible when another part of the system simultaneously gains the same amount of energy. When you say: > this energy (of wave nature obviously) passes through the slits The question then is what type of object would possess this energy as it passes through the slits and hits the screen behind it. Since the screen is specifically set up to detect electrons, the simplest explanation is that it is really the electrons performing the interference. (Footnote, just to be safe: Energy conservation can be broken on very very short timescales, but this is not relevant for the double-slit experiment.)