Translator: Chelsea Esterline
Reviewer: Denise RQ I think as long
as we're attacking enigmas, it'd be good idea for us
to just shoot for the stars. Let's solve the enigma of the universe. Here you can see an image
of my colleague Dave and I. We both work on the Large Hadron Collider, and we really enjoy talking to the public,
obviously, about what we do. Here we were hosting a virtual visit of some students
about 12 and 13 years old. They were joining us from Seward, Alaska, and this virtual visit gives them
a chance to sort of ask scientists, "What's it all about? What are you guys doing over there
smashing particles together?" Sometimes, the best questions,
in fact, most of the time, the best questions come from young people, "How do we measure what we can't see?" I think if I try to answer
that question here, we'll make a big leap towards understanding
the enigma of the universe. So let's give it a try. I think we can do it. What is it that we see, right now,
when we look at the universe? I'm going to show it to you. Are you ready? Here we go: nothing, nothing,
nothing, nothing, nothing. Nothing! Something, intergalactic gas, nothing, nothing, nothing,
nothing, nothing, nothing, nothing, nothing, nothing, nothing,
nothing, nothing, nothing, more interstellar gas, nothing, nothing, nothing,
nothing, nothing, nothing [Kind of humbling, isn't it?] (Laughter) nothing, nothing, nothing,
nothing, nothing, nothing, nothing. Oh, that's us. Wait, that's us. That's our galaxy. Nothing, nothing, nothing,
nothing, nothing, nada, nada. Sorry, nada, nada. Nothing, nothing, nothing,
nothing, nothing, interstellar gas, nothing, nothing, nothing,
nothing, nothing, nothing. So you've guessed it. The universe is
exactly what you expected it was: a dark beer. (Laughter) (Applause) OK, I can finish now. It's what we all expected. It's 96% stuff that we can't see. It's only that small 4% at the top
of the things that we are able to see. So when a particle physicist tells you
they're doing a really good job, remind them that they're
missing 96% of the universe. Let's try to solve some of that if we can. How do we know this? How do we see what we do see, and how do we know
what the universe is made of? Well, this tool has been
serving us extremely well since the beginning of mankind. For millions of years,
we've been using this, and it's an amazing tool. The human eye can see
to one 1/100 of a degree in precision. That means that we can look
at my colleague Eva's hair. She has very fine, blond hair;
that's why I chose her for this. About 40 microns... Don't ever say that us guys
aren't observant, OK? About 40 microns her hair is. You can't go much better than that,
but that's pretty good precision. That's for something up close. We can also see something
very, very far away, 2.5 million light years away, there's this galaxy out there
called Andromeda; and we can see that with our bare eyes. We don't need anything more. So we're happy, right? Good enough? No, we're human beings. Human beings have
this insatiable desire to know more. It's just what we're made out of. That's what drives us;
that's how we survive. We need to learn more
about the world around us. We want to know
the answers to many questions. Where did we come from? What are we made of? Are there rules that govern all of this? Is there anything else
out there that we don't see? Over time, we've come up
with a couple means to address this. We use these together. We answer like this: exploration. We try to see more all the time. We've developed instruments,
we've developed tools, which allow us to expand our vision: telescopes to look out,
microscopes to look in, and we travel everywhere
that we possibly can. So we expand what we can see. But in addition to that
we have extrapolation. We try to figure out what's beyond. What else is there? We've developed methods over time:
mathematics, science, formulas that allow us to go beyond
what we actually see physically. Over time, we've developed tools to allow us to look out
into the heavens to see more. These tools give us
better and better precision. They use things beyond light. In fact, we've gone so far
that we even now, very recently, were able to use our ears to note waves in the space-time of the universe
that started way, way back in time. We can actually hear
the ripples of space-time. We also like to look in, in more detail. Maybe we want to see
Eva's hair a little bit better. We've developed microscopes. We've learned how to use other things
besides photons, besides light to be able to probe inside matter. This is an electron microscope. We also have developed these devices. This device, the Large Hadron Collider at CERN, right now is probing the deepest depths
that we possibly can at the moment. That's where we're at the moment; that's where we're trying to solve things. What have we learned from all this? Well, in looking out, we've learned that we live on
a beautiful little blue planet. It's one of eight or nine planets
revolving around a sun. It's a pretty normal sun sitting in the suburbs
of a wonderful galaxy, that's one of a hundred
billion stars in a galaxy, that's one of a hundred
billion galaxies in the universe. We've also learned about time; we've learned how we've evolved, that the universe started
in a Big Bang 13.8 billion years ago, and that our universe
that we're in is expanding. I'm going to get back to that. Looking in, we can see the depths
of the hair, for example; inside there are cells. Those cells are made of molecules, molecules are made of atoms, atoms have nuclei, the nuclei have protons and neutrons, and now we know that protons
and neutrons are made out of quarks. In fact, we've gone so far
that we have a very nice model, something that was drawn up in the 1960s, but now which we've completely
mapped out and filled out today, something we call the Standard Model
for lack of a better name. There is the Standard Model: you see the particles,
but you also see an equation. That equation tells you
how those particles interact. So that's what we can see. There are still some things that remain. Remember, 96% remains. Let's take a look at that. Back to the beer, because I figured you guys would want
to get back to the beer at some point. The 73%: that's something that we call
dark energy or invisible energy. When we measure the rate at which galaxies or clusters
are moving away from each other, we have found, fairly recently, that it's not just
that the universe is expanding but that expansion is accelerating. Things are going further and further away
from each other more quickly. We can calculate how much matter
there is out there, and then calculate how much energy
it would take to do that. You guys all know energy is matter: E=mc^2. So, how much energy does it take to push everything out
at the rate it's going, to accelerate it? That turns out to be
about 73% of our universe; dark energy. Another enigma that we have. We look at galaxies. A great astronomer
named Vera Rubin noted this. She figured all galaxies
must work just like the Solar System. The planets in the Solar System,
you can look at how fast they turn around. They turn fairly quickly
towards the center, but on the outside
they're going more slowly. You can calculate all that. I'm sure you guys all know how to calculate all that
with classical mechanics. It can be done. You expect exactly
the same thing from galaxies. It's not at all the case. The stars on the outside of galaxies
move too quickly for what you would expect and the only way that Vera
could calculate the movement was if she added more matter. In fact, it took 80% more. So, out there in a galaxy,
and also in space in general, there is 80% of our matter,
which is stuff that we can't see. It's been called dark matter
or invisible matter. We don't know what that is. And a third enigma:
of this matter, whether you see it or not, every single fundamental particle
gets its mass somehow. This is a strange thing. A fundamental particle, you may have seen them visualized
like this red ball here, they're actually pointless. Pointless. That's a bad way to put it.
They're actually pointed. They're point particles.
They don't have a volume. Yet, they have a mass. That's a very, very strange thing. How does something
which doesn't have a volume have a mass? We didn't understand that. It doesn't make sense. And they have different masses. How do you explain that? Who knows which of these enigmas
have been solved? Anybody knows? Anybody wants to guess? Which one of these enigmas
has already been solved? It was solved... You know. The last one. On July 4th, 2012, we celebrated the fact
that a proposal that was made in 1964 by Peter Higgs, Francois Englert,
and Robert Brout was correct. They proposed that there exists
a field everywhere commonly called the Higgs field, and a particle that we discovered
at the time called the Higgs Boson was the carrier of the force of that field
and this explained how things get mass. But, a discovery is great, and of course
we enjoyed it, and we celebrated, but it was much more important than that. This particle, this field
has a very important property. It is the key to unlocking another enigma. The reason for this is that if you look very carefully
at the arrow next to his beer - there's a lot of beer in this - next to his beer you'll see that the Higgs boson couples
with all particles with mass, right? Dark matter is dark, and it's matter. It has mass. Therefore, if we can measure
that particle very carefully, maybe we can solve this. Let's work on that. You can see here, of course, for those of you who are used to looking
at Lagrangians and equations in physics, the bottom two lines of this formula
carry that Higgs field in it, and they tell us all massive particles
will interact with the Higgs field. There's a key here. There's something that can help us out. So let's solve this, OK? As long as we're here, before lunch. It's always good to get
something done before lunch. Let's solve the enigma. We're going to use something
called the Large Hadron Collider. It collides protons together. A lot of people think of it AS you're smashing stuff together
to see what's inside. That's not exactly quite right. What we're trying to do
is squeeze these particles as close together as possible
at high energy so they can have a chance to interact. At the points where we make them
go right next to each other we put these big beautiful detectors. This is the ATLAS detector. I'm very biased because I work for ATLAS. There are four beautiful detectors
on the LHC, and they're at the points
where we make these collisions. What happens when they collide
is you see something like this. This is a fairly recent image that we took when we had our proton collisions
at 13 TeV that started last year, and it's going to start up again
in a few weeks. We're going to start doing a lot of this. What we do is we look at
what comes out when there's the collision. We look at the different types
of particles and the numbers that come out of that. Anybody know Heisenberg? Ever hear of him, Heisenberg? Heisenberg told us
that there's a little area. The Heisenberg uncertainty principle
tells us there's a little area
that we'll never see. No matter how beautiful
of a detector we make, no matter how powerful of an accelerator
that we make, there's a little area. Can you see it in there,
the little, little, black area? Inside that area, we will never
really know what's going on. But that's the trick. That's really the trick. Just thinking about
what goes inside there. This is what the extrapolation part is,
the theory part. We often call extrapolation, theory. Theorists are allowed
in that small black area, but experimentalists like myself,
we just measure what comes out, and we try to figure out what's going on. I'm going to give you an idea. We're going to zoom in on that. I happened to bring it right here. What's interesting about this box, which I took right out of the beam,
expanded it a bit (Laughter) is that the entire universe
is inside here. Absolutely everything is inside this box. Anything that can happen, happens. That's what quantum field theory is. You didn't expect
to learn quantum field theory, but you're going to now. Everything happens inside here. Particles interact, those rules that I put up there before
of the Standard Model is what we thought for a long time
is what happens in here, but that only explains
4% of the universe, right? What we hope is something else. Let me give you an example. Let me just show you here. I brought a few particles. Let's start with this. Here's a Higgs boson. I happened to get one. We actually have a few thousand of these. It took quadrillions
of collisions, by the way. Quadrillions is ten to the whatever. It's a really big number. You need a lot of collisions in order
to produce some of these Higgs bosons. But that never stopped us. We like to do this stuff. Physicists, you know. The Higgs boson couples,
when we say couples we mean it interacts, with other particles. Let's call this guy the Higgs Boson. Here's another particle. That particle gets its mass
by interacting with the Higgs boson. We make a whole bunch of these things. We call these vertices. All of these are explained
with that formula. We have a whole bunch
of different vertices, different connections,
that we're allowed to make and that's what the model tells us. This is supposed to explain
what comes out of the box. All we see is stuff
sticking out of this box. We have to from that extrapolate, go inside and figure out
what stuff's in there. Now here's the key. This is where the enigma gets interesting because what we hope is
this darker stuff here, this dark matter. If we have something that's stable
and that's massive, and is a fundamental particle,
it will interact with the Higgs boson. So by measuring this guy,
now we've got it. We've had it for 3, almost 4 years now. We've got that Higgs boson. By measuring a lot of interactions, we will be able to see something which goes beyond what we thought
was inside that box. It'll be something that will change it. We will see different proportions
of particles that come out or something. Something will surprise us and it will break the rules. At least that's our hope. To get back to the question
that was asked, how do you measure what you can't see? First of all, you imagine. [Imagine] You imagine what's inside that box. (Applause) Secondly, hold on a second. I know you're hungry. (Laughter) Then, we explore. [Explore] We explore as best we can
with the best tools we possibly can, and we have to have a lot of patience. We might be able
to find something this year. We're going to have a lot of collisions
this year in the LHC. It might take the full 20 years
we're going to be running. It might take the next accelerator. But you have to explore, explore, explore. Finally, when you're lucky
you break the rules. [Break the rules] I think when I looked out in the audience, I saw a little bit of doubt from people when I said the entire universe
was in this box, and I think that it's very important
that everybody here know that you should never,
ever, ever doubt a TEDx speaker. The universe is in the box. Thank you. (Applause)
