LHC question - probably one for jake!

[Loosehead]

http://www.bbc.co.uk/...-environment-11711228
They say here that a temerature of ten trillion degrees is produced. Is that merely a mathematical calculation of the temperature that should be produced in this collision or do they have any way of actually measuring it?

[jake-the-peg]

The "temperature" is a measurement of energy that the lay man is supposed to be able to relate to.

They work in electron volts or Mega electron volts or Tev in this case 3.5Tev a new record

Changing it to Temperature's a bit silly really because in effect people can't relate to trillions of degrees any more than Tev

[Loosehead]

Right so it's the energy of the collision translated into temperature for the masses to digest. Thanks.

[jomifl]

It seems that they don't use a thermometer Doc, at least not one from Argos.

[jno]

the usual form would be to express it as 'a temperature the size of Wales', Loosehead.

[boxtops]

...especially not the sort you test the dog's temperature with....

[daftgrandad]

Or in the same way boxy !

[Loosehead]

well I see we have the usual "geniuses" venturing out of numpty land. Thanks jake for an actual answer.

[jno]

chill out, Loosehead!

[jake-the-peg]

I thought jno's answer was quite insightful

x times the size of Wales does seem to be a stock science writers way of communicating scale as does the predictable y times hotter than the center of the sun.

There seems to be an overriding desire to try to put things in everyday terms even when it's pointless to even try.

They really only need to say that they now have the record for the most energetic collisions ever achieved and are still only winding up.

All the same it's nice to see a good news story from CERN after all the early - "it cost a mint and it's broke again" stories

[beso]

Temperature, by definition, is a measurement of the average kinetic energy of the particles in the sample. The fluid in a thermometer rises with temperature because the particles bang together harder and bounce further. A solid generally expands with temperature because the atomic bonds shake harder and thus lengthen.

There is nothing "silly" about the temperature in the LHC as it complies strictly with the definition of temperature. Just because a person may be unable to relate to a trillion degrees does not in any way lessen the fact that that is the temperature of the plasma.