If you have even the slightest interest in
science, by now you've probably heard of an
exciting new scientific facility called the
Large Hadron Collider or LHC.
But what do you know about it?
Well first, the LHC is a particle accelerator.
It is located at the CERN laboratory in Europe,
just west of Geneva, Switzerland.
This accelerator takes two beams, each containing
about 300 trillion protons, and shoots them
at one another.
Even though there are lots of protons in the
beams, individual collisions are only between
two protons, one travelling in one direction
and one travelling in the opposite direction.
For the subatomic world, these protons have
an enormous amount of energy, although from
a human perspective, it's really very small...
about as much energy as a mosquito flying
at full speed.
However this energy is concentrated into an
incredibly small volume.
The result is that when the protons collide,
they experience temperatures of tens of trillions
of degrees centigrade, which is over a hundred
thousand times hotter than the center of the
Sun.
In order to get a feel for what those conditions
are like, we could ask if we wanted to make
a ball the size of a basketball with that
energy density, how much energy are we talking
about?
The answer is simple.
A lot.
And I'm not kidding.
It would take the energy of the Sun itself.
And I'm not talking about the energy of the
Sun hitting the Earth, I'm talking about all
of the energy of the Sun.
And not just for a second, a minute, a day
or a year.
If you could take the entire energy output
of the entire Sun for over 20 million years,
and concentrate that energy into the size
of a basketball, that's what it's like in
the center of an LHC collision.
Studying matter under these incredible conditions
allows us to learn what the universe was like
a tenth of a trillionth of a second after
the Big Bang and to work out some of the most
fundamental rules that govern the universe.
And we've already had a huge triumph.
In July of 2012, we announced the discovery
of the Higgs Boson, which was the last missing
piece of our current best theory of the laws
that govern the universe.
When the 2013 Nobel Prize in Physics was awarded
to Peter Higgs and Francois Englert for the
prediction of the Higgs Boson, the entire
scientific world basked in their glory.
Of course, even with such a momentous discovery,
we're not done.
I mean, if you're in a mine and you find a
huge nugget of goal, you don't stop.
You keep digging.
And LHC scientists are doing just that.
After taking data from 2010 to late 2012,
the LHC was temporarily shut down for refurbishments,
retrofits and upgrades.
The Spring of 2015 is the beginning of a new
period of data taking that is expected to
run for several years.
Even better, the new and improved LHC really
is that- new and improved.
It will collide particles at over 150% the
energy it did before and with far more collisions
per second.
With these enhanced capabilities, scientists
will look for all sorts of things, hoping
for a discovery.
You might ask "what are we going to find?,"
but that's really a very silly question.
After all, the LHC is a machine of discovery.
To paraphrase a famous scientist, if we knew
what we were going to find, it wouldn't be
called research.
But we do know what we're going to look for.
We're going to look for supersymmetry, extra
dimensions, precision tests of our existing
theories and deeper investigations into the
properties of the Higgs boson, and maybe even
make the dark matter that astronomers say
is five times more prevalent than ordinary
matter.
And, of course, we'll be scouring the data
looking for something entirely unexpected.
That would be the coolest outcome we could
hope for.
There's another interesting aspect of the
LHC.
For those of you who might not have a scientific
interest but are fascinated by engineering,
the LHC is an outrageous accomplishment.
The LHC is a ring about 17 miles in circumference:
27 km.
The beam travels around the ring about ten
thousand times a second.
To guide the beam in a circular path takes
9600 magnets, of which 1232 are especially
strong.
These magnets, called dipoles, use about 11,000
amperes of current to make a magnetic field
160,000 times stronger than the Earth's magnetic
field.
The energy stored in the magnets is 11 billion
joules.
That's enough energy to melt fifteen tons
of copper.
When the beam is put in the accelerator, it
circulates for a long time, say about 10 hours
or so.
During that time, the beam travels far enough
to go to Pluto and back.
In order to have a beam travel that far, the
beam is kept inside a pipe that is under high
vacuum.
The vacuum is ten times better than the surface
of the Moon.
And the total volume in the beam pipe is about
the same as one of Europe's majestic cathedrals.
And if all those numbers weren't enough to
blow your mind, the center of the magnets
are cooled to incredible temperatures, to
1.9 Kelvin or 456 degrees below zero Fahrenheit.
By any definition, the LHC is a spectacular
scientific achievement.
And the thing that makes the whole endeavor
so incredibly exciting is that the experiments
we do might discover something entirely new
and change our entire understanding of the
universe.
We'd have to rewrite the textbooks.
But you know, I am totally up for that.
How about you?
