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fsh

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With smaller reactors, one needs more of everything: reactor vessels, containment structures, cooling systems, generators, etc. This is why industrial facilities are usually built as large as reasonably possible, and why SMRs fell out of fashion as soon as GW-class reactors became feasible in the 1960s.

That would poison the entire country. Nuclear waste is many many orders of magnitude more radioactive than coal per energy generated. The meme about coal emitting more radiation comes from a 1970s paper that compared radioactive emissions and found them to be on the same order of magnitude between a BWR and an unfiltered coal power plant.

The original iPhone was genuinely terrible. A 2006 Nokia could surf the web on the go and tell you where you are. The iPhone could do neither, since Apple did not include a 3G modem or GPS. It also did not have any apps, and one of the key features highlighted by Steve Jobs was voicemail. The 3G one year later was the first truly usable iPhone.

Japanese public transport is good, but no match for the Swiss system. Outside of big cities, the coverage is spotty, and even reasonably large towns are only connected by reserved-only trains every couple of hours that get booked out days in advance. The almost complete lack of digitization is also remarkable (reservations have to be made with machines in the stations). There are other annoyances such as the public transport in Tokyo shutting down completely at midnight. In contrast, the Swiss government-owned system delivers usable connectivity to almost any human settlement, even most mountain villages. The ticket prices are also not so different, which is surprising considering the large difference of salaries in the two countries.

I find the editorialized title misleading. They trapped 17000 atom pairs in an optical lattice and demonstrated a high-fidelity quantum gate between the atoms of each pair in parallel. There is no interaction between the atoms of different pairs and no individual control. The experiment demonstrates a very robust gate scheme, but is a long way from a programmable computer.

F-35 Got Hit 4 months ago

"Quantum radar" is a toy experiment with zero practical applications. The experiments achieved a "quantum advantage" by using entangled photons which only works in the single-photon regime. Since microwave photons are pretty small, this implies incredibly low transmission powers. With the typical return loss of an airplane (stealth or not) detected by a radar antenna, one would have to average for centuries to detect something (assuming the airplane stays there for said centuries). This assumes perfect entanglement with no other imperfections.

Essentially none of this is true. The war of the currents was between Edison and Westinghouse, not Tesla. Tesla's downfall was that he turned into a crackpot who rejected modern science, such as Maxwell's equations, and started defrauding investors. Edison was an outspoken opponent of the death penalty, and the electric chair used AC simply because it is much more deadly.