[rapjr9]

> Why can’t they make visible light with an antenna?

Why can't an oscillator and antenna emit matter? Is some matter transparent to other matter in the same way that some matter is transparent to light? This idea that matter and energy are equivalent and that the same wave physics underlies it all doesn't seem to be true in reality. Instead it seems that phenomena are divided into regimes and in each regime behavior is very different. Sure it's tough to build an oscillator at the frequency of matter, but is it really impossible to build a matter emitter? I only have a BA in physics but I remember while learning (and in later reviews of physics) that it seems like theory doesn't always scale and there are a lot of very weird assumptions and "explanations".

[amluto]

You can (for the most part) produce bosons (e.g. photons, aka light), individually or in big piles, out of thin air. You cannot produce fermions (e.g. electrons, protons, neutrons) out of thin air like this. To make an electron, you need to also produce a positron or do something else that satisfies the various conservation laws. You can make an electron-positron pair in a collider, but doing this in large amounts takes absurd amounts of energy.