Per: http://news.yahoo.com/s/nm/20100215/sc_nm/us_physics_temperature
Hottest temperature ever heads science to Big Bang
Hottest temperature ever heads science to Big Bang
By Maggie Fox, Health and Science Editor Maggie Fox, Health And Science Editor Mon Feb 15, 11:23 am ET
WASHINGTON (Reuters) Scientists have created the hottest temperature ever in the lab -- 4 trillion degrees Celsius -- hot enough to break matter down into the kind of soup that existed microseconds after the birth of the universe.
They used a giant atom smasher at the U.S. Department of Energy's Brookhaven National Laboratory in New York to knock gold ions together to make the ultra-hot explosions -- which lasted only for milliseconds.