Looking at the Big Bang
The energy density attained at LEP corresponds to a temperature of one
trillion degrees, 1015 K. With existing theories, we can
calculate how long the Universe took to "cool" to this temperature after
the Big Bang, and we find that it is only a tenth of a billionth of a
second, 10-10 s. In other words, what particles reveal to us
in LEP collisions is the way the Universe behaved just this tiny fraction
of a second after the Big Bang.
Particle collisions at LEP have helped us to probe the first instants
of the Big Bang, which in turn has helped us to understand the way the
Universe is today.
Particle Physics Education CD-ROM ©2001 CERN
