yeah if we just look over here down in
the valley there is where
cern is and
the sps collider provides the initial
protons and from those initial protons
they then lead to the generation of the
neutrinos and those neutrinos then fly
off
through the mountain range through the
mountains through the mountain range
there and over to another set of
mountains in in italy grand sasso
mountains it's it's amazing to be here
and just
you suddenly realize you can talk about
it all you like in a room and you think
my god it's shooting straight through
that rock
there what happens when neutrinos hit
rock nothing
absolutely nothing that's the beauty of
neutrinos they only interact through the
weak force the weakest of of all the of
of all the forces electromagnetism
strong and the weak and the and and they
just don't even notice the rock at all
it's as if the rock might be a bit of
fog that they're just going through
and of course the the exciting result
that they was uh put was announced a few
months back i think in september of
2011.
was that the when they took the timing
of the neutrinos that were created and
detected they created here just outside
of this of cern and then detected in the
grand sasso laboratories worked out the
distance and they knew the time and they
worked out the speed the the velocity of
these neutrinos were faster than the
speed of light and the time difference
was just 60 nanoseconds so they were
arriving 60 nanoseconds earlier than
light would arrive
quite
rightly the experimentalists have been
you know reanalyzing everything they can
because it's such a radical result if
it's true
and they're going through everything and
it looks like they've found
a couple of sources of error that may
account for this difference yeah so it's
to do with um actually one of them is to
do with the cabling that takes them from
the gps system that they're using to
their own to their own optical system
it's an optical cable
and it sounds like it wasn't quite
connected well enough and when they've
tightened up the connection
the time delay that was that they were
recording a 60 nanoseconds seems to have
gone away completely i'm not an
experimentalist so i'm not one to
criticize i'm not going to criticize
them because
i've had loads of occasions when i've
got had loose wires and i can't get
things to transmit
well i think i think that they they've
done things the right way i think they
will get criticism for this if it turns
i mean it's still not proven that this
is gonna actually screw up the result
because there's there's two effects that
they've noticed one could actually of
course the neutrinos to go even quicker
whereas you know this one is saying that
actually they might go
you know there's two effects going on
they're competing with one another this
isn't the only possible source of error
or um they've they have another they've
talked about which i don't really
understand which is also to do with this
timing it's again to do with the
coordination between the the gps system
that they're using uh to calibrate and
and their own timing mechanism and
there's a they have this other source
which
intriguingly they say that these two
sources of error one the connection and
one this other source which i don't
understand is they're working in
opposite directions so
you know they could cancel each other
out if they cancel each other out then
the result's still there but at the
moment the feeling is probably that they
won't and that that result may disappear
they were sitting on this for three
years they didn't know what the uh you
know what
if there was anything wrong you know
they'd looked at it looked at it looked
at it i sort of liken it to darwin
actually when darwin came up with the
origin of the species his religious
convictions meant that he was very
nervous
about announcing it to the scientific
community and he sat on it for years
right it's a bit like that in a way
because they realized the controversy of
what they were going to announce
and
and so they sat on it and they i
wouldn't want to sit on it forever the
right thing to do is to open it up to
the rest of the scientific community and
they can study it and they can see if
they can find a fault i think that's the
right thing to do when we stand here and
look at those mountains
it really hits home to me how amazing it
is that neutrinos pass through mountains
what happens when fred the neutrino
is passing through that many atoms that
much rock how come nothing's hitting
anything the the the fred the neutrino
is you
you i think i think it's not a bad
analogy is you basically would replace
that rock as far as fred is concerned
with nothing more than a veil of fog
or
it's and you're passing through
and you just you you just bypass it
right you don't you might see it but you
just would go straight through it you
won't you don't interact with it in any
real way and it's only very occasionally
will will fred actually feel the impact
of one of the atoms that's and in fact
it basically passes all the way through
the rock and and the thing that ends up
detecting it
is an even more concentrated regime of
the detectors they use are really solid
detectors of lead which has got high
density of atoms in there and basically
you've just got to increase the density
of atoms as much as you can of so that
the nuclei of the atom the the you
maximize the chance that this neutrino
which has got no inter no
real interaction cross-section
which means you know the area that it's
going to hit with anything else that's
so small that it just passes all the way
through it's a point-like object
remember it's a fundamental object as
the neutrino it just shoots through and
you've you've got to be very lucky that
it actually hits one and and and leaves
a recoil that you can detect so you
maximize the density of material it's
passing through the gaps but also it's
it's not experienced it's got no charge
a neutrino has got no electric charge so
it's not feeling the effects of the
protons it's not feeling the effects of
the electrons at least in terms of the
electromagnetic interaction which is far
stronger so the protons and neutrons are
highly they're all there and they're
producing electrostatic interactions but
the neutrino doesn't feel then it's not
feel it doesn't feel the strong
interaction so this high density of of
of protons and neutrons which have got
all the quarks in there
the neutrino doesn't feel those strong
interactions the only thing it's it's
beginning to feel are the the weak
interactions that's the only thing it
feels and they're much weaker
than
than any of the others so basically it
just goes through feels everything is a
gap
personally if it isn't proved to be a
real effect
i will be gutted
as a theorist i'll be absolutely gutted
you know this is so exciting you know
when i when when it looked like it might
be a credible result you know me as a
theory thought you know i'm sort of
working in this field at a time when you
know as a hugely dramatic result has
occurred and you know that really
excited me and you know the game was on
to try and find ways to explain it you
know i'd already thought of a project
for one of my phd students potentially
you know to try to explain this result
probably won't bother now
so something like a nucleus has various
weapons in its arsenal to affect other
other particles
and a lot of its weapons or one of its
big weapons is neutralized in the case
of a nutrient absolutely that's it's
electronic it's the electrostatic forces
are neutralized and its strong forces
are neutralized the two big weapons it's
got are gone and it's just left gravity
is irrelevant is so weak on these scales
it's just left with the with your weak
interaction with being weak
means it's very difficult to detect them
yeah i'm always an artist on these
things i like interesting results like
this you know you don't you don't do
science for the just to sort of do the
boring old well i don't do science to do
the just boring old stuff you know i
want to i want to do interesting stuff i
want to do exciting stuff you know stuff
that's you know
is really sort of moving on from what we
previously thought that's what excites
me as a scientist you know maybe you
know i would like these sort of
anomalous results to come out you know
when i was doing my phd
and
that's when it was announced that uh the
acceleration of the universe which was
last year's nobel prize was given for
and uh you know i remember at the time
people were very skeptical about that
and you know if you say oh it'll just be
some systematics whatever
but actually that's turned out to sort
of that stood the test of time it seems
this one might not but you know at the
time that was a huge zone it's dominated
my career since that acceleration of the
universe results so you know this is
what it does these these are great
things you know we should embrace these
things obviously we need to be
scientifically responsible and you know
not just jump on a bandwagon because it
sounds good
but you know these are exciting things
and as i said i'll be gutted
thanks
in a little bit further
this is great
how often do you see that
wow