Linked from
The 25 pages that link to Cryogenics, each with the reason it gives.
Absolute zeroNarrower topic: It developed methods for approaching absolute zero in real materials.
KelvinRelated: Kelvin quantifies the temperatures at which cryogenic materials and systems operate.
Liquid nitrogenNarrower topic: Liquid nitrogen is a common working fluid in cryogenic systems.
Argon fluorohydrideRelated: Cryogenic temperatures help prevent trapped HArF from decomposing.