Cooling copper plates could slash data center energy use by 90%

I think the main idea is that MOSFET chips don’t sink or source much current on their own (“fundamental” seeming to mean the way that current does not propagate into the gates, and most designs only really draw current during transitions)

OTOH some chips (amplifiers for example) may indeed have current flowing through them and therefore the power consumption of the “chip” would equal the sum of heat loss and output power. At least that’s my interpretation of the framing “how they operate at a fundamental level”. I could be wrong too, I’m not a working EE

It could go into the information directly. https://en.wikipedia.org/wiki/Landauer%27s_principle

Not really. They use aluminum fins because they are way lighter and cheaper. The copper tubes are actually heat pipes that transfer the heat through liquid/vapor phase change. And copper is used because the liquid inside is water (aluminum would corrode) and they are also easier to bend into shape (aluminum fatigues easier with bends, and pores would allow the liquid to escape).