Twenty-one grams. That is the mass of all of the electrons in
your body if, like me, you weigh about 70 kilograms. Now all of the mass comes from the Higgs mechanism,
which means that as your electrons are traveling through space time, they interact with the
Higgs field and it is that that gives them their mass. It slows them down and stops them from traveling
at the speed of light. But most of your mass doesn’t come from
the Higgs mechanism. And neither does all of this stuff that you
see around you. The mass is coming from somewhere quite different
and that is because most of your mass and most of this mass comes from neutrons and
protons and they are not fundamental particles. They are made of constituent particles called
quarks. Now the theory that describes quarks and their
interactions with each other through gluons is called quantum chromo dynamics. And chromo is the Greek word for color. So in some way these objects are meant to
carry the color charge. But they are much, much smaller than the wavelength
of visible light, so there is no way that they are actually colored, but it is a useful
analogy that helps us think about how they interact and the particles that they can make
up. Now the rules are pretty simple. In order for a particle to exist, it must
be colorless or white, like this house. Now you can accomplish that in two different
ways. You could make three quarks in where each
one is a different color, red, green and blue, so overall they combine to produce white. Or you could use a quark and an anti quark
where one is a color like green and the other is its anti color, say, magenta. Now what I would like to do on this little
patch of beach behind me is simulate how quarks actually bind together and form different
particles. Now for this you need to remember that in
the last video we talked about how empty space is not truly empty. So the beach here is has these undulations
in it which represent the fluctuations in the gluon field. But you have to imagine this beach sort of
rippling and these bumps coming and going. Now that is really important, because to get
rid of those fluctuations actually takes energy. And this is an important part of binding the
quarks together. The existence of quarks actually suppresses
the gluon fluctuations and creates what is called a flux tube, an area where there is
really nothing in the vacuum and that is in between this quark and the anti quark. And that pairs them up and creates what is
called a meson, the quark, anti quark pair. What is interesting about that flux tube is
that as these quarks become more separated, the flux tube remains the same diameter and
the same sort of depth of suppression of the field, which means that the force doesn't
actually increase. It is not like a spring. It is not like an elastic band. The force is the same that is pulling these
quarks back together. But you are putting more work in as you move
these quarks and anti quarks further apart. And so for a time people thought: Well, these
quarks are always going t be confined, however far you move them. You are just going to get a really long flux
tube. But what actually happens is you that you
put in enough energy that you can actually create a quark, anti quark pair. >> Nevertheless, the quarks are still combined. You can never see an individual quark, because
if you try to pull it out, you put so much energy into the situation that another quark,
anti quark pair will be created. >> Now to form a proton, we are going to need
an up quark, another up quark and a down quark. Now the standard model of a proton that you
have probably seen involves these quarks bounded together by little gluon springs that go between
them. >> We know that that picture is totally wrong
now. Even in the best sense you might have hoped
that you would see flux tubes around the edge of the triangle. But we know that, in fact, they don’t do
that. That you get these y shaped flex tubes. >> The crazy thing about a proton is that
there may be more than three quarks there. You see, you can have additional quark, anti
quark pairs pop in and out of existence. So at any given time there could be five or
seven or nine, any odd number of quarks could make up a proton. So this is what a proton actually looks like. You can see that the quarks like to sit on
those lumps in the gluon field. And you can see the two up quarks and a down
quark, but there is also a strange quark and an anti strange quark, which is strange, because
you don’t normally think of these quarks being inside a proton, but they can be at
any particular point in time. And you can also see that these quarks have
cleared out the vacuum. And you can see that there is kind of these
flux tubes which are the areas where the gluon field has been suppressed. And that is really what is binding these quarks
together. >> That is the strong force that binds quarks
into the heart of the proton. >> It is intrinsically related to the fact
that clearing out those fluctuations has more energy than where they are. >> That is right. It costs energy to clear the vacuum. >> So where is the mass of the proton really
coming from? Well, of course, the constituent quarks do
interact with the Higgs field and that gives them a small amount of mass. But if you add up the mass of all the quarks
in the proton it would only account for about one percent of its total mass. So where is the rest of the mass coming from? The answer is: energy. You know, Einstein’s famous equation: E
equals mc squared. Well, that says we have got a lot of energy
for just a little bit of a mass. But if you rearrange the equation you can
see that we can get an amount of mass if there is lots of energy there. And that is really where most of the mass
of the proton is coming from. It is from the fact that there are these energy
fluctuations in the gluon field and the quarks are interacting with those gluons. That is where your mass is coming from. It is coming from the energy that is in there. You know, Einstein talked about, well, if
I had a hot cup of tea, it would actually have a slightly greater mass than the same
cup of tea when cold. And he was right. I mean, you can’t measure it with a cup
of tea, but most of your mass you owe to E equals mc squared, you owe to the fact that
your mass is packed with energy, because of the interactions between the quarks and these
gluon fluctuations in that gluon field. I think it is extraordinary, because what
we think of as ordinarily empty space, you know, that turns out to be the thing that
gives us all most of our mass. I really want to thank Audible.com for supporting
this episode of Veritasium. In case you don’t know, Audble.com is a
leading provider of audio books with over 100,000 titles in all areas of literature
including fiction, non fiction and periodicals. You know, one of my favorite books is by James
Gleick. It is called The Information: A History, A
Theory, A Flood. And if you head on over to Audible.com/Veritasium
you can download it right now for free. Or you could pick another book of your choosing. You know, it is great to have support from
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This title is so wrong...The mass comes from all the energy being concentrated onto a small amount of "stuff".
The binding energies are the rest of your mass.
Mass = energy, Einstein anyone?
all of it is energy
I believe in the one electron universe. Blasphemy.
hmmmm... interesting
Idiette