CERN Physicists Generate Hottest Man-Made Temperatures Ever: ~5.5 Trillion K 107
Diggester sends this quote from Nature News:
"Physicists at CERN's Large Hadron Collider have achieved the hottest man-made temperatures ever, by colliding lead ions to momentarily create a quark gluon plasma, a subatomic soup and unique state of matter that is thought to have existed just moments after the Big Bang. The results come from the ALICE heavy-ion experiment — a lesser-known sibling to ATLAS and CMS, which produced the data that led to the announcement in July that the Higgs boson had been discovered. ALICE physicists, presenting on Monday at Quark Matter 2012 in Washington DC, say they have achieved a quark gluon plasma 38% hotter than a record 4 trillion degree plasma achieved in 2010 by a similar experiment at Brookhaven National Laboratory in New York, which had been anointed the Guinness record holder."
Re:How was it measured (Score:5, Informative)
Curious (and too lazy to google)-- At 5.5 trillion K, they aren't going to just stick a thermometer in there. How do they measure how hot the plasma was?
Temperature is related to energy. So by measuring how much energy is in the quark-gluon plasma you can deduce its temperature.
Another example is how do you determine the surface temperature of stars ? We sure as hell don't send thermometers to the sun, or to other stars. So how do we know that the surface temperature of the sun is roughly 6000 K ? You mesure how much energy the sun radiates, and by using a theoretical model (known as a black body) you can establish a relationship between amount of radiated energy and temperature. Therefore you can deduce the temperature of the sun (or of other stars).
Re:How was it measured (Score:2, Informative)
Probably using a specialized technique which I have no idea of. From TFA:
Re:Meaningless (Score:5, Informative)
If anything is published in a forum that also caters to Americans, you can safely assume that the short scale was used. While people elsewhere can convert, most Americans can't, whether this is due to ignorance, incompetence or hubris.
The long system makes more logical sense:
one billion = one million ^2
one trillion = one million ^3
one quadrillion = one million ^4
As opposed to the short system:
one billion = one thousand ^3
one trillion = one thousand ^4
one quadrillion = one thousand ^5
I.e. the name versus the exponent is always off by one.