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the speed of light is basically
is fast as you ever get
What is it in American units, something like one hundred and eighty six
thousand miles a second
but on our account we can slow them down to 38 miles per hour- that's what
we did in our first experiment
and then we actually slowed them down all the way to to one mile an hour and
then you can actually
you can basically crawl faster than light
what we do is we a bunch of atoms, and we use what I call sodium atoms, exactly what
you have in table salt
and then we cross-manipulate these atoms in very special ways with
laserbeams and then we can cool these atoms down to a few billionths of a degree above absolute
So, of course, that's really cold. It's actually the coldest place in the universe.
And then once we create a cloud
of such really cold atoms we illuminate that cloud with one laser beam
and then we send a light pulse
into the cloud from the other side and we can now slow that light pulse down to the
speed of a bicycle and it sort of chuffs along.
And then, if we feel like it, we can actually completely stop that light pulse inside our atom
cloud
and then leave it there for a while, park it there, and then when we feel like it,
cloud send the light pulse back on its way, revive it, regenerate it, and out it comes.
what we are seeing here
is actually the atom pool, really, because as I mentioned, we create these really cold atoms
and we need laser beams to do that.
And eventually these laser beams are really running around,
criss cross on the optics table.
And then they converge on the vacuum chamber where all the action is happening.
And then up here, behind, we have a very special atom source-
that's where the sodium
atoms are coming from. And they are hot to start-
we actually have to heat them to create a gas of sodium atoms... And at the time when we 0:02:00.190,0:02:02.299 started to go after cold atoms
I did not have a clue that some years later I would start to look at slow light forces. And that's really
an example of,
if you get your hands on an exciting new system,
you start to poke it
and see what comes out
And what you hope is that something totally unexpected, totally exciting
will come out and and i think that's what happened in this case.