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Coldest temp achieved: 450 picokelvin
http://cua.mit.edu/ketterle_group/Projects_2003/450picokelvin.htm

Hottest temp achieved: 10^13 K
http://hypertextbook.com/facts/2003/TiffanyGillyard.shtml
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http://liquids.deas.harvard.edu/penanen/workings.html