In article m, Martin
Underwood writes
- superconductivity occurs are very low temperatures (approaching 0 kelvin)
not at very high temperatures - this error is a classic

Not quite, Lord Copper.

Superconductivity occurs when there is effectively[*] zero resistance
to electron flow. Ways that this can happen [+] include a half-empty
energy level with Bose-Einstein statistics and a regular progression of
completely filled energy levels with Fermi-Dirac statistics (these being
responsible for He4 and He3 superconductivity respectively). There may
well be other mechanisms.

It so happens that all known cases of superconductivity occur at
extremely low temperatures (under 10K) or very low temperatures (perhaps
150K, I forget), but there is no theoretical reason why it couldn't
occur at room temperature or even at 400K (123 degrees C) or above.
[*] Not "effectively" as in "almost", but "effectively" as in "as if it
was". I have a vague memory that there's actually some resistance in one
sense, but other effects exactly balance it. BICBW.

[+] This is based on my memory of various bits of reading on the topic.
I'm happy to accept correction from professional quantum mechanics.

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