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November 23, 2018 73 mins

Surprisingly the field of particle physics poses a handful of existential threats, not just for us humans, but for everything alive on Earth – and in some cases, the entire universe. Poking around on the frontier of scientific understanding has its risks. (Original score by Point Lobo.) 

Interviewees: Don Lincoln, Fermi National Laboratory senior experimental particle physicist; Ben Shlaer, University of Auckland cosmologist University of Auckland; Daniel Whiteson, University of California, Irvine astrophysicist; Eric Johnson, University of Oklahoma professor of law 

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Episode Transcript

Available transcripts are automatically generated. Complete accuracy is not guaranteed.
Speaker 1 (00:06):
Man made black holes, low energy vacuum bubbles, strange lits.
These are some of the ways that an ill conceived
physics experiment could pose an existential risk, not just for humanity,
but for all life on Earth and possibly for every
atom in the universe if things go particularly badly. Physics

experiments seem like an unlikely place to find a clutch
of existential risks, but it makes sense. Really. There are
no other branches of science that explores the places where
something is magic. Is accidentally creating a tiny black hole
could happen. Physics is the purest branch of science. Back
in the thirties, physicist Ernest Rutherford put it something like

all science is either physics or stamp collecting. Physics, in
particularly particle physics, is the place where the leading edge
of science explores new frontiers of the universe. It's as
literal as that. But we are still at an early
spot in our understanding of particle physics, in the place

in human history where you and I live. Now, those
forays by the leading edge of science are blind pokes
in the dark, and we face a dilemma because of this.
We can't understand the universe without poking at it, but
we can't really say if poking at it is safe
until we poke it. The idea that particle physics could

end the world sounds like nothing more than paranoid fantasy,
born from something like fear of science and it's big,
hulking machines that blast invisible particles into one another, but
concerned that dangerous exotic stuff could be created inside a
particle collider come from the physics community itself. Physicists are

aware that they know enough about physics to build machines
that can simulate nature, but don't know enough to say
for certain just what will happen inside those machines. We
don't know enough to know that those experiments were running
are existentially safe, but we're doing them, pushing the envelope
anyway and hoping for the best. To understand how things

like low energy vacuum bubbles and man made microscopic black
holes could accidentally be made here on Earth, you have
to know a few things about physics first, and I
will tell you everything you need to know. To start,
I'll need you to hold your hand up in front
of your face. I want you to focus on, say,

the back of your hand. Hold it up in front
of you. Gaze upon it, kind of lose yourself in it.
Let your eyes come in and out of focus, so
that your hand becomes the only thing in the world. Now,
find some little spot on your hand and focus on it.
Let your self be drawn into that spot, drawn into

your hand. As you travel into that tiny point on
your hand, you will grow smaller and smaller and smaller,
so that you can pass easily through your own skin,
past your bone, and into your veins, further and further inward,
growing smaller as you descend, shrinking through your blood and

plunging into one of the giant, gummy disc red blood
cells in it, growing smaller and smaller, so that you
pass right through the cell walls untouched, smaller and smaller
among the galaxy of a hundred and twenty trillion atoms
that make up a single red blood cell. Plunging into
the electric cloud that envelops one single fuzzy oxygen atom,

you are surrounded by the electrical field, like a fog
that encapsulates the nucleus and binds the electrons to it
A million miles away. Here inside the atom, you will
learn the truth of the universe. Everything looks different than
what you've always learned in school. There is no atomic
solar system, with the nucleus as the sun and the

electrons like planets in orbit. The electrons are everywhere and
yet nowhere at once and at the center. There is
no proton, no neutron. There are no particles like tiny
pieces of matter, like crumbs of the universe. There are
only vibrations of energy. These are the true building blocks

of the universe, the corks and the gluons and all
of the other elementary particles that make up everything that
the material world is built from. You are here in
the quantum world, and now that you look around, you
see that there are vibrations everywhere. All around you, you
see fields of different kinds of energy passing through each other,

interacting with one another. And within those energy fields are
countless moving, pulsating vibrations. Look back upward, now up from
your place in the quantum field, pass the atoms to
the cells and out of your hand. Look up to
your own face and to the sky and the sun
behind you. All of those things, you, the sky, the

sun are made up of spectacularly complex arrangements constructed from
the energetic vibrations of complimentary force fields, entangled by irresistible
forces until time runs its course for them and their
arrangement collapses when they break down and travel along their
fields until they are attracted into some new arrangement. From

a frog as it dies, to the algae of a
pond that decomposing, to the belly of a fish, to
the mouth of a mother, to the iris of a
newborn child. The cycle of life and death is nothing
more than the movement of energy along a universe of
force fields. You can see now that everything, every site

you've ever seen, everything you've ever touched, everything you've ever
smelled or tasted, every emotion you've ever felt, all of
it is made from the interaction of the energy fields
that make up our universe. Even you, you can see
now that you are a bundle of discrete vibrations held

together by attractive forces in the hyperlocal area of the
universe that until a few moments ago you always thought
of as your body. Pinch your thumb and your index
finger together tightly. The sensation of pressure that you feel,
there's nothing more than the electromagnetic force pushing back against itself.

Physicists have known all of this for more than a century,
and now you see the true nature of the universe.
Every thing is energy. All of the vibrations in the universe,
and so all of the matter in the universe are

remnants of the energy left over from the Big Bank.
Almost every vibration unleashed, and the first trillions of a
second after the Big Bank came in equal and opposite pairs,
and they canceled each other out. They annihilated each other,
almost all of them, but not all. This is Don Lincoln.
He's a physicist at Fermi Lap near Chicago. Very early

on in the universe, there was some asymmetry, some little
difference between the two of them. And what happened is
there was a very slightly larger number of matter vibrations
than antimatter vibrations, something to the tune of three billion
to three billion and one. And then the three billions
canceled and the one was left over. And that's the

matter of abrations that are left that make up the
what we see now in our universe. Why there is
something and not nothing is one mystery that particle physicists
have run across while plumbing the void. Another is exactly
where our universe came from. It's looking increasingly likely that
there was nothing that came before that our universe erupted

randomly from an aberration in an energy field, like a
bubble of steam rising in a pot of boiling water,
and in fact, the basis of a theory by physicist
Roger Penrose from Oxford University called conformal cyclic cosmology, says
that this is just the way that universes are formed.
One bubbles up, lives, dies, and leaves nothing behind but

the remnants of the black holes that formed in it,
which are scooped up in the structure of the next
universe that bubbles up to replace the old one. To
us living in this universe, such a process would take
the longest scales of time a man tenable, but to
someone with a different perspective of time, perhaps watching universes
bubble up, collapse, and bubble up again might be like

watching a pot of water simmer. All of this is
to say that if our universe arose from an aberration
in an energy field, or from the remnants of the
collapsed universe that came before ours, then it could happen again.
Our universe could be reborn in a different form within
itself and from a closer look at the Higgs field,

it appears that it's constantly trying to do just that.
One of the energy fields that make up our universe
is the Higgs field. It is the field that gives
mass to other energetic vibrations. Without the Higgs field, nothing

would have mass, which means that the Higgs field is
the energy field that allows you and all other matter
in the universe to physically exist. Without mass, there cannot
be matter to be bound together, and without matter, there
cannot be chemistry, which binds that matter together and creates
new forms of matter. And so without chemistry there can

be no life, which means without the Higgs field, there
can be no life, which is one reason the Higgs boson.
The particle that carries the energy of the Higgs field
and interacts with other particles, is called the God particle.
The other reason is that God particle was originally short
for the God damned particle, which is what physicists called

it because it eluded them for so long. It seems
a bit heavy, but think of mass is just another
property that a vibration can have, like how a ball
can be read, round and bouncy all at the same time.
When you know what properties of ball has, you can
predict what it will do in any given situation. Like

if you drop the ball, you can say that it
will probably bounce a couple of times and then roll away.
And since it's red and round, you know what to
look for when you go try to find it in
the grass to get it again. The same goes for
sub atomic particles too. Their properties, like their electrical charge
and their mass, let physicists predict how particles will interact

with particles from other energy fields. And since everything is energy,
if you can understand how every energetic particle interacts, you
can understand everything. And since Einstein showed the world with
his E equals MC squared equation that mass and energy

or just two sides of the same equal sign, you
can just look at mass like it's just another type
of energy, which it is. When a vibration arises, let's
say a cork from the cork field, it interacts with
the boson from the Higgs field, almost like it's coded
by it. And now that cork has mass, so it

can be acted on by other fields like the gravity field.
These fields, the cork field, the gravity field, the Higgs field,
all of the fields, they are everywhere, at every point
in the universe. The Higgs is the only field that
can give mass to other vibrations, and it has another
unique property too. It is the only field that still

has an energy when it's turned down to zero, which
is surprising. If you could turn down all of the
energy fields in the universe to zero on some master
universe style, there would be no electrons at all in
the electron field, no corks, no glue ons, all of
the energetic vibrations would cease, and yet energy would still

persist in the Higgs field. It's like if you turn
down the volume on this show to zero, yet you
could still make out faint pops and crackles in your headphones.
It would lead you to believe that there was some
setting below zero that you could turn the volume down to. Well.
Physicists have arrived at the same conclusion about the Higgs field,

but this opens up an unsettling possibility. If the Higgs
field isn't currently at its lowest energy state, and the
Higgs field is what gives matter mass, then if the
Higgs field ever slipped into that lowest energy statement, the
mass of everything in our universe would suddenly change. In
other words, we would all disintegrate. This is theoretical physicist

Ben Schlayer from the University of Auckland in New Zealand.
Particle physics and the corresponding chemistry would be suddenly very different,
and in particular, matter would no longer be at the
right size. The different sizes of the atoms that make
up matter are based on the distance between the electrons
and the outer periphery and the nucleus at the center.

If electron suddenly got heavier, adams would shrink into smaller size,
which means everything in our universe would suddenly shrink. All
of the matter around us would suddenly find itself unstable
to a great shrinking, and as it shrank, it would
give off a huge amount of electromagnetic energy. So they'd
be an explosion of X rays and that would be

a pretty violent event. Two theoretical physicists, Sidney Coleman Frank
DeLucia determined back in that this new lower energy state
of the universe would not support chemistry, which means that
life would not have the chance to re evolve in
this new version of our universe. They called this vacuum

decay and said that it was the ultimate ecological catastrophe.
But things can actually get worse from there because the
shrunken universe is denser than it was before. That means
gravity acts on all of the mass throughout the universe
more forcefully, too, so that vacuum bubbles outward. Expansion will

eventually be and then reversed as it's pulled backward, returning
to where it started, like an implosion, forcing all matter
into an infinitely dense, infinitely tiny ball, possibly the very
same place where our universe started from. This is called
the Big crunch. It's the antithesis of the Big Bang.

Spacetime ends and the universe ends. In a big crunch,
it would be like our universe never happened. That the
Higgs field has balanced between its current state and the
lower energy version of itself means that it poses a
natural existential risk to us. If it moved into that

lower energy state, that would be it for not just
human existence, but for everything in the universe. So the
Higgs field actually poses a universal existential risk for now
and for the foreseeable future. At least, the Higgs field
is in a state called meta stable. The good analogy
is a puddle in a valley at the bottom of

the hill. On the other side of the hill, say
there's an even lower valley, and the Higgs puddle would
be happy to settle into that lower one. But it
would take a tremendous amount of energy for the puddle
to move itself up the hill to the other side,
energy that the puddle doesn't have, so the Higgs field
won't be moving up the hill. But there's another way

that it could slide into that lower energy state. Unnervingly,
the Higgs is constantly trying to tunnel through that metaphorical
hill to get to the lower valley on the other side,
and this attempt to tunnel through comes in the form
of indescribably small pockets of this other lower energy version
of the Higgs field that at every moment bubble up

from it like a simmering pot. But these lower energy
Higgs bubbles are too weak to overcome the external pressure
or universe exerts on them, so they wink out of
existence just as fast as they arise. The trouble is
that if one of those lower energy bubbles ever does
manage to stick around long enough to stabilize and grow,

it would swallow our universe and bring about that vacuum
decay that Coleman and DeLucia wrote about and disintegrate our
version of the universe. It would be a big crunching deal,
you could say, But probability is on our side. Under
normal circumstances, the chances of one of those lower energy

version bubbles growing are so low it's not expected to
happen over the estimated lifetime of our universe, so we
appear to be in the clear again. Though that's under
normal circumstances. We humans have a tendency to alter normal circumstances,
and there's a way that the Higgs field campose an

anthropogenic existential threat. A vacuum bubble could grow with the
help of a microscopic black hole, which we might actually create.
Inside one of our particle colliders. Here on Earth, m

about a hundred meters beneath the countryside where Switzerland juts
up from the southeast into France. Above sits the Large
Hadron Collider, the largest highest energy particle collider in the world.
Hadron is a name for sub atomic particles like protons
and neutrons that are made up of quarks and gluons.

Those energetic vibrations that make up matter. If you could
go inside the LHC reduce yourself back again to the
scale of those energetic vibrations, you would see something spectacular.
The protons in the Large Hadron Collider are created by
passing a laser through a cloud of hydrogen gas, which

breaks the atoms apart. Those stripped protons are directed into
the LHC's vacuum tubes by an electrical current, and they're
separated into two beams that are kept apart and sent
in opposite directions around the elliptical collider. Over the course
of days, the beams are accelerated until they reach unimaginably

fast speeds point nine nine nine one percent the speed
of light, where a single proton can make the trip
around the seventeen mile circumference of the collider more than
eleven thousand times in a single second. At these speeds,
the protons carry with them as much as five trillion

electron volts of energy, an extraordinary amount for something so small.
It's like a mosquito with the kinetic energy of a planet.
When the beams are at their highest speeds, they're directed
into each other so that they cross inside of one
of the collider's enormous sensitive detectors. Every second a billion

collisions take place, and the energy from those impacts turns
into mass, which creates particles for just a fleeting moment
that we're around right after the Big Bang. So the
LHC is a way to rewind nature, to study its origins.
To me, it's like I think of using particle colliders
to understand the universe as an exploration. We're like looking

for new stuff and you never know what you find.
You know, this is particle physicist Daniel Whiteson from the
University of California, Irvine, And one strategy we have to
understand these things is just to look for patterns among
the particles. And the way to look for patterns is
to see more of them. That's the goal of using
the LHC to explore the universe. We want to find

more particles, get more clues, see sort of a larger
window into the reality that we're seeing currently, and hopefully
get some insight. The Large Hadron Collider was first brought
online in two thousand nine after decades of planning and construction,
and it woke up in a world where the field
of particle physics had hit a wall. The LHC was

designed to break through that wall. It was designed, you
could say, to break physics. The work of particle physics
can be divided between two groups. On the one hand,
you have theoretical physicists. They come up with all the
ideas about how the universe might work, and on the

other hand, you have experimental physicists who test those ideas
in machines like the Large Hadron Collider. The work of
these two groups forms in aura borros, the mythical snake
that eats its own tail. The experimental physicists find support
for the theoretical physicist theories, or they say that they're wrong.

The experimental physicists also come up with new data that
the theoreticians can use to create entirely new theories that
the experimental physicists can then test. As a deeper understanding
of particle physics develops, the snake grows fatter. In the nineties,
sixties and seventies, the theoretical physicists dropped a huge amount

of new work on the desk of the experimental physicists.
A group of theoreticians wrote down everything science knew about
the quantum world and What they came up with is
a set of formulae known as the Standard Model of
particle physics. Over the decades, the Standard Model has been
proven correct again and again. The Standard Model does a

really good job at describing the particles that exist in
the quantum world and the forces that govern them. The
strong nuclear force binds protons and neutrons into the nucleus
of an atom. The weak nuclear force causes atoms to
decay over time. The electromagnetic force binds atoms together into
higher structures like you and meat, and the sun, and

mosquitoes and red blood cells. Every particle that the Standard
Model predicted should exist by now has been discovered. It is,
as scientists put it, an extremely reliable model to describe
the quantum world. The last of the bunch was the
Higgs boson, which the LHC found in two thousand twelve,

and with that discovery the experimental physicists exhausted the theoreticians
standard model. But as good as the Standard Model is,
as reliable as it is, it's been incomplete from the
very beginning. It has no place for gravity, and vice versa.
With Einstein's famous theory of relativity. It's proven extremely reliable

at describing how gravity governs the interaction of large scale
things like people and planets. But the other three fundamental forces,
electromagnetism and the weak and strong nuclear forces don't fit
into the equation partum field theory. It really doesn't deal
with the universe as a whole, and it's well known
that general relativity does not merge in mill well with

a quantum realm. So what physics has on its hands
are the standard model and the theory of relativity too
totally accurate but totally incomplete pictures of the universe that
won't fit together to form a cohesive whole. It's almost
like they repel one another. Particle. Physicists built the large

hay Drown Collider to figure out why that is. They
hope that the incredibly high energy collisions will produce new
particles that don't fit into the standard model to show
where physics should start looking next. One of the biggest
mysteries of all that physicists are hoping to solve is
why gravity is so weak compared to the other three

fundamental forces. It's strange. Gravity is the force that keeps
planets in orbit around massive stars and can catch light
by the ankles and prevent it from escaping a black hole.
Yet the other three forces are stronger, and you can
see this for yourself if you just lay a paper
clip on a countertop and hold a regular old refrigerator

magnet over it. As you bring the magnet closer, the
paper clip will eventually rise to meet and stick to it.
What you've just seen is the electromagnetic force and that
tiny magnet overcoming the gravitational force exerted by the entire
mass of planet Earth. Like I said, strange. To make

sense of this, and to unify relativity in the standard
model into a theory of everything, some physicists have taken
to adding new dimensions to our universe. Some models see
our four dimensional world of length, with height and time
as just a tiny membrane floating within an infinitely larger

fifth dimension that we can't sense, called the bulk. Others
include as many as eleven total dimensions, most of which
are curled up into extremely tiny coils at the corners
of every point in the fabric of spacetime. These models
explain why gravity is so weak by allowing it to

spread across all of the dimensions. The other three forces,
like us are trapped within our four D world, but
gravity is not. And if we could sense all five
or eleven, or however many dimensions there are, we would
see that gravity has the same strength as the other
three forces. It just seems weak to us because it's

diluted by comparison inside our four D world. So one
way that physicists are hoping that the LHC breaks physics
is by revealing the presence of other dimensions. And a
really good way to demonstrate that there are other dimensions
would be to create a microscopic black hole. Those aren't
supposed to exist in our four D world until the

idea came along that's such a thing as microscopic black
holes could exist. We used to think that we understood
black holes pretty well. It was sort of a golden
age of black hole understanding. We learned over time that
black holes were gaping, all consuming, horrific abominations in space time,
with masses so huge that they boggle the mind. Sure,

but we could feel good about them. We understood them,
and we were here, and they were a way out there.
They had no way to touch our world, let alone
end it. From studying them, we found that black holes
were created when some incredibly massive star far larger than
our Sun, exhaust at its fuel and collapsed under an

unimaginable force of gravity into an infinitely dense, smaller version
of itself that actually pushed a bottomless pit in the
fabric of time and space. Encircling the rim of this
black hole is the event horizon, the threshold where the
gravitational poll is so strong that anything crossing it is

doomed to be forever trapped inside the black hole, torn
apart by the unimaginable gravity with it. Over time, we
began to notice black holes everywhere we could detect them,
ripping apart nearby stars, pulling them into a ring of
hot gas, and circling the event horizon like water around
a drain. We began to find them at the center

of galaxies, including our own Milky Way, which nourishes a monstrous,
supermassive black hole the size of four million of our sons.
We saw that black holes could cannibalize other black holes,
which forms even larger black holes, and perhaps the fate
of our universe was to one day be swallowed into

one giant black hole made up of every black hole
that's ever existed in every universe that's ever existed, But
like any good golden age, this one was not meant
to last. It ran from the time black holes were
predicted in Einstein's theory of relativity in nineteen fifteen until
about the mid seventies, when a not yet world famous

physicist named Stephen Hawking proposed some ideas about black holes
that suggested that maybe we didn't understand them so well
after all. For starters, Hawking and his colleagues proposed that
black holes didn't have to be made of something as
big as a star. Black holes could actually be incredibly tiny.

This was news. It's true that anything with mass can
be turned into a black hole if it's made dense enough.
If the Earth were condensed to do a black hole,
it would have an event horizon about as big around
as your index fingernail. But as far as physicists understand it,
the Earth could never actually become a black hole because

it simply doesn't have enough mass for gravity to collapse
it into that infinite density. It takes a truly sincerely
massive object like an enormous star to undergo that sort
of transformation. What Stephen Hawking and his colleagues realized back
in the seventies is that there are actually times in

the universe's distant past, say within trillions of a second
after the Big Bang, when everything was much much denser,
and so during this time, something with a mass like
the Earth's could have collapsed into a black hole back then,
and much much smaller things could have two, maybe even particles.

Hawking called these hypothetical particle sized black holes that may
have formed in the very early universe primeval black holes.
Today people call them microscopic black holes. In addition to
his theory that such a thing as very tiny black
holes could possibly exist, there was another thing that Hawking
realized that brought our golden age of understanding black holes

to an abrupt end. It was actually possible for them
to spit matter out. He said this was news too.
Our understanding of black holes at the time was that
they did nothing but consume, ceaselessly, growing eternally. The idea
that they could spit stuff back out was pretty revolutionary.

The idea that black holes could actually radiate energy came
to be called appropriately Hawking radiation, and Hawking showed that
a black hole could emit photons and gravitons, the particles
that carry electromagnetic energy and gravitational energy, respectively. Normally, these
particles don't have matt mass, they don't interact with the

Higgs field. But what Hawking figured out is that the
less massive a black hole is, the hotter the temperature
of the radiation that it spits out, which means a
very very tiny, microscopic black hole with a very very
small mass would actually have extremely hot radiation because its

mass is so small that radiation could be hot enough.
Hawking realized that the photons and gravitons the black hole
spit out could actually have mass themselves. And here's why
temperature is a measure of heat. Heat is a form
of energy, so high temperature means high energy. And since

mass and energy are two sides of the same coin,
E equals mc squared. Remember, mass and energy are theoretically interchangeable,
which means that heat can be translated into mass. Another
way you could put it is that if the energy
of a normally massless particle like a photon or a
graviton has a high enough energy, it will interact with

the Higgs field and get coated with mass, and a
microscopic black hole could produce photons and gravitons with energies
that high. If Hawking was correct, then that means that
over time a tiny black hole could actually lose mass
itself as it spit out photons and gravitons with their
own mass, and at some point, when the microscopic black

hole lost enough mass, it would wink right out of existence.
Black Holes aren't supposed to do this. It seems we
didn't understand black holes nearly as well as we thought
we did. Are comfortable Golden Age came to an end.

It's about here where the story begins of how cern,
which actively messes with the mass and energy of particles,
took up a long time quest to prove that it's
large hadron collider won't do humanity. Actually, wait, it begins
a little before the LHC came along. The story really starts.
In that year was, as far as anybody knows, the

first time anyone seriously raised the idea that a particle
collider might be able to end the world. Scientific American
Magazine published a letter from a reader who wasn't so
sure that the relativistic heavy ion Collider at the Brookhaven
National Lab in New York nicknamed the Rick, was entirely safe.

The reader was concerned that the rick might produce a
microscopic black hole, the kind of thing that Hawking proposed,
when particles collided inside of it. Scientific American published the
reader's letter along with a response by a physicist named
Frank will Check, and will Check pointed out classical six
doesn't allow for microscopic black holes to exist at all.

That's point one. Point two was that even if the
theories that include additional dimensions, theories that are beyond classical
physics and actually do allow for microscopic black holes to exist,
if those additional dimensional theories turn out to be true,
the energies of the particle collisions in the rick were
still far too low to actually create a microscopic black hole.

So no worries, Well, there was one worry. At least.
Will Check did mention that it was much more likely
the Rick could produce an exotic type of matter called
a strangelet. Strangelets are heavy particles made of smaller vibrations
called strange quarks. Despite their heavier size, they're actually lower

energy than typical strange quarks, which means that the universe
would prefer them over strange corps. It's just that strangelets
tended as all very quickly because of their higher mass.
The concern over strangelets is that if one of them
didn't dissolve into elementary particles, it could conceivably set off
a chain reaction, lowering the energy but increasing the mass

of the matter that makes up Earth, converting our planet
and everything on it, including us, into a massive, inert
dead bulk. Will checks offhand comment at the end of
his reply set off a separate, years long tangent of
uneasiness and investigation into strangelets and whether they have the
goods to pose in existential risk themselves. But at least

the microscopic black hole terror was put to bed, or
so it seemed. The terribly disconcerting idea of a man
made black hole has a habit of winking into existence
again and again. A couple of years after the Scientific
American readers black hole question was asked and answered, the
looming specter of a potentially world ending black hole created

in a particle collider rose again, like a new universe
rising to replace an old one. This time the collider
in question was the Large Hadron Collider, which was beginning
to be assembled in Europe. This time around, the fears
weren't quite so unfounded, because the energies of the collisions
in the Large Hadron Collider are an order of magnitude

higher than the ricks, high enough, in fact, that if
any of those multidimensional theories are correct, the LHC should
be fully capable of producing microscopic black holes inside of it.
So capable, in fact, that a two thousand one paper
by physicists Stephen Gettings called the LHC a black hole
factory and calculated that it could produce a microscopic black

hole every second it's proton beams were crossed. Now it's
here where CERN began its long standing quest to prove
the Large Hadron Collider is safe. On the one hand,
the idea that the LHC might be able to break
open the current understanding of the universe and point theoretical
physicists in a clear new direction is intensely exciting for

the particle physics community. But on the other hand, CERN
was much less excited about the idea of everybody else
seeing their machine as a black hole factory that could
end the world. And it's pretty easy to understand why
the funding for certain at any given point is precarious
enough under the best of circumstances, they count on public

funds from multiple nations and work under the threat of
those funds drying up at any time, and the stakes
for keeping the Large Hadron Collider funded are very high.
This is law professor Eric Johnson, who has written extensively
on the risks that come along with high energy physics experiments.
It's really hard to downplay the amount of money and

the amount of professional lives that are involved with the
Large Hadron Collider. Uh. CERN is a multibillion dollar institution.
UH there's thousands of people who work there and in
the field of particle physics. In the field of particle physics,
there really aren't It's not like everyone's off doing their
own experiments. Particle physics tends to be dominated by the

big collider of the day and the data that it's producing.
And if that collider doesn't come online, then there's nothing
to study for a whole lot of people. Protecting certains
enterprise is made all the more difficult by the fact
that what it is doing is pure science. There's no
obvious research and development that can be turned into useful

products that the nations involved can expect to make back
some of their investment with instead. The LHC is as
unadulterated as scientific experiment as you will find on Earth.
It was designed and built solely so that we can
better understand the universe in our place within it. A genuine,
noble public good to benefit all humankind. It can be

tough to make money off of else. That is not
to say that the Large Hadron Collider hasn't already produced
dividends well beyond physics. You could argue and plenty do.
That's certain paid for itself many times over. Back in
the late nineteen eighties, when one of its computer scientists,
a British man named Tim berners Lee, created a method

for linking text files so that they could be shared
universally over computer networks. Burners Lee called it the Worldwide Web,
so that it could protect its funding, calm fears among
the non scientific public, discover whether the LHC actually is
an existential threat or all of those things. CERN took

up its quest to demonstrate that the Large Hadron Collider
will not doom humanity, who would be a long and
circuitous route so at that point cern couldn't rely on
the not having enough power to produce black Hall's argument
for safety, and they they acknowledge the need for a

new examination of hazards, and uh they went back and
did some new work on that, and then they said
in two thousand three that Hawking radiation will ensure that
any black hole that's produced will evaporate almost as soon
as it's produced, so that that will be safe. Because

any microscopic black holes the colliding particles inside the LHC
might manufacture would have extremely small masses. Hawking radiation says
that they would emit particles and lose their mass at
a blinding speed, winking out of existence instantaneously. Just how
fast that would happen, called the rate of decay, would

be a fraction of a fraction of a second, something
like ten to the negative power of a second, a
decimal point, followed by zeros, and then finally all the
way down in the position a single one that fraction
of a second. In this unimaginably short time, the microscopic

black hole would have no chance to absorb any matter
and grow larger. On this infantism le small scale matter
is just too few and far between, so the microscopic
black hole would be gone before we knew it was
ever there, but it would leave telltale traces behind that
the LHC's detectors could find and show the world that

there are dimensions beyond our own. But this argument that
suggests the Large Hadron Collider is safe comes with some baggage.
Between the time that the research began on the safety
paper and when CERN released it, the physics community's faith
in the existence of Hawking radiation was shaken. In the
early two thousands, the trickle of papers began to question it.

It wasn't disproven, just question enough to erode it as
the kind of thing that CERN could fet the survival
of the planet on. So CERN looked for another way
to show the Large Hadron Collider was safe, and this
time they settled on cosmic rays. Cosmic rays aren't exactly

what they sound like. They're actually tiny energetic particles that
travel at incredibly fast speeds through space and smash into
other particles, creating a spectacular cascade of energy converted temporarily
into mass. And if this sounds a lot like the
collisions inside the Large Hadron Collider, you're absolutely right. A
particle collider is, if anything, a laboratory for stimulating cosmic

ray collisions, and because they're so similar, means that since
cosmic rays bombard everything in the universe all the time
and have for billions of years, then the fact that
the universe still exists proves that even if particle collisions
can create microscopic black holes, that microscopic black holes must
be harmless, because again, the universe continues to exist. That

is the cosmic ray argument, and it's the second thing
that's certain pinned the safety of the Large Hadron Collider too.
But there's a problem with the cosmic ray argument as well.
Cosmic rays aren't exactly like particle collisions inside the Large
Hadron Collider, and exactness is kind of important when you're
trying to show the world that your machine won't bring

about the end of the universe. Cosmic rays travel at
high speeds, yes, but the particles that the cosmic rays
smash into, say particles in the Earth's atmosphere, are just
kind of hanging out there. They're relatively stationary, which means
that the collisions are a lot like rear end collision
and most importantly, in a rear end collision, the momentum

of the faster vehicle or particle carries it and the
other vehicle or particle careening off in some direction away
from the site of the crash. This is important because
it means that if cosmic rays do produce microscopic black holes,
the momentum of the crash would carry the microscopic black
holes away from the collision to most likely they'd pass

harmlessly through Earth and right out into outer space. The
problem is in a particle collider, the collisions are different.
They're less like rear end collisions and more like head
on collisions, and then a head on collision, the two
particles cancel one another's momentum out when they collide, they
don't go anywhere. The upshot of all of this is

that a microscopic black hole produced by the collision wouldn't
go careening off away from the impact and into outer space.
It would be stationary. It would stay put, which means
that it would stay put here on Earth. That is
a problem because if we've already thrown out the idea
of hawking radiation, and along with it, the concept that

a microscopic black hole would simply wink right out of
existence if it was created, then that means that if
we do create a microscopic black hole in a particle collider,
it would hang around here on Earth, which means that
it could possibly grow, which means that it actually might
pose an existential threat to us. As far as safety

arguments go, this is decidedly not reassuring, especially considering the
idea of the two thousand one paper by Stephen Gettings
that said that the LHC is a black hole factory.
If that paper was correct, then a new, stable, earthbound
microscopic black hole is created inside the collider every second

it's proton beams are crossed. So certain looked again for
a new way to show that LHC was existentially safe.
What they needed was something out there in the cosmos
that was dense enough to have a gravitational pull that
could hang to do a microscopic black hole. Something that
could do that would show again simply by existing, that

microscopic black holes really are harmless. It would show that
even if the Large Hadron Collider produced a microscopic black
hole and the Earth hung onto it, there's still no
cause for concern. It was basically cosmic ray argument two
point out, and CERN finally found what they were looking
for in white dwarf stars. A white dwarf is a

star that's run out of fuel and has partially collapsed,
so it becomes far denser and exerts a much stronger
gravity on things around it, definitely more than Earth's gravity.
So any microscopic black holes that a rear end cosmic
ray collision could produce would still be stuck in the
star that wouldn't careen off into outer space. And since

white dwarfs are bombarded with those cosmic rays, and since
they enough gravity that they could trap a microscopic black hole,
then the fact that they continue to exist strongly suggests
that microscopic black holes are not a danger. That is
to say, again, if microscopic black holes even exist. Based
on astronomical measurements of white dwarfs, CERN found eight of

them that, in their opinion, were dense enough and old
enough to sufficiently demonstrate the safety of the large Hadron
collider certain issue of paper, and it was followed by
another paper that concluded the first paper was sound, and
they circulated both papers to the physics community, which in
turn provided CERN with quotes about just how sound the

conclusions of the papers are and just how utterly safe
they show the LHC to be. Certain included these quotes
on their website, and that's where things stand today. Classical physics,
which represents our current understanding of physics, doesn't allow for
microscopic black holes to form in the place. But even

if those microscopic black holes could form, so long as
those eight white dwarfs exist in the sky, Certain is
willing to bet the whole farm on the safety of
the LHC. But with physics, our understanding has a way
of changing. The whole idea of particle physics is to
discover new things. Particle physics works at the leading edge

of human knowledge, at the leading edge of theory. That's
the whole point of it is to be out there
trying to figure out something new. So it does evolve
all the time. And I think it would be naive
to say that right now this year, we've arrived at
a point where the theory is not going to change,
or the assumptions are not going to change, so that

we can feel satisfied that whatever conclusion particle physicists have
today about the safety of a particle accelerator that that's
not going to change m M. By now, you might

be asking yourself exactly how might a black hole be
created inside the large Hadron collider? Well, that is an
excellent question. When you take a little tiny particle like
a proton, and accelerated to almost the speed of light,
something very peculiar happens to it. The little amount of
mass that it has starts to grow, and as its

mass grows, the stronger the gravity acting on it grows too.
A very fast particle accelerated in the Large Hadron Collider
begins to grow enough mass that it warps the fabric
of spacetime around it. This warping has the effect of
concentrating gravity, and in the minute fraction of a moment

before two extremely fast moving particles collide, they're bent gravity's
over lap and concentrate gravity even further. The sum of
all these parts amounts to an unusual amount of mass
and extremely high gravity concentrated within a very very tiny area.
All of this together could produce a microscopic black hole.

Because it would lack the kind of escape velocity that
a cosmic ray might give it. The microscopic black hole
would be held fast by the gravity exerted by the
Earth's mass. About every half hour, the microscopic black hole
would oscillate between the LHC and a point on the
opposite side of the world, somewhere off the coast of
New Zealand, and back inside the Earth. The black hole

would grow over time, but exactly how long that process
would take depends, as does everything, it seems like, on
the correctness of one of the unifying theories that combine
relativity with the standard model. One of the things that's
so unsettling about the idea of Hawking radiation, the theory

that a microscopic black hole will wink right out of
existence just as fast as it's created, is that whether
Stephen Hawking was right or wrong, microscopic black holes still
pose an existential risk. If Hawking was wrong and there
is no such thing as Hawking radiation, then a microscopic
black hole could stick around and slowly eat the world.

What would a black hole eating the Earth from the
inside out look like, Well, it's hard not to imagine
a microscopic black hole growing in the Earth's core until
it emerged on the planet's surface, kind of popping out
as a gaping bottomless pit that some hapless person wandering
through the woods might accidentally stumble into. But this isn't
what it would look like at all. Remember, if the

Earth itself could be compressed into a black hole, it
would have an event horizon just about a centimeter in diameter,
So any microscopic black hole that consumed all of the
Earth's mass would have an event horizon about the same size.
A microscopic black hole then would never pop up on
Earth's surface. It would still be unnoticeably tiny as it

tore the planet apart. Plus, let's not forget we couldn't
see it anyway, being a black hole, like couldn't escape it,
so it couldn't reflect off the black hole's surface, which
would make the microscopic black hole both tiny and invisible.
But we would be able to clearly see the effects
it had as it tore our planet apart. One of

the defining traits of a black hole is, of course,
the intense gravitational pull that it exerts on matter around it.
Black Holes are capable of pulling matter literally apart, and
as it does, it releases enormous amounts of energy. That
violence produces extremely high temperatures and all of that hot
torn apart matter becomes trapped in an orbit around the

black hole. Eventually that matter falls past the event horizon,
unable to escape. Particles that the microscopic black hole encounters
in the quantum world would be among its first victims.
But as it grows over time, the black hole would
eventually get big enough to devour whole atoms. And as

the black hole grows, so too will its strength. The
more it increases in mass, the more of the Earth
it will draw into it, pulling Earth apart and into
that gaseous stew of hot matter that circles around it.
Over time, the magma, the bedrock, the soil, the lakes,
the very planet itself would be pulled apart. There would

be no place left for life to live on Earth,
which would be a moot point anyway, since every bit
of life on Earth would be pulled apart as irresistibly
as the planet itself, drawn into that roiling circle of
plasma around the black hole, which would slowly feed on
our planet for a very long time. Under classical physics,

the time it would take for a tiny black hole
produced in the LHC to gain enough mass to become
a threat to life on Earth is longer than the
current age of the universe, more than thirteen billion years,
but that time shortens dramatically when new dimensions are added.
The additional dimensions allow for stronger gravity on those quantum scales,

which would allow a microscopic black hole to attract and
consumed particles early in its life much more quickly. Such
a black hole could destroy the Earth in as little
as three hundred thousand years, which is a bit alarming
considering the possibility the LHC has been creating a microscopic
black hole every second it's been colliding protons to as

it came online back in two thousand nine. Humanity might
still very much place a high value on our home
planet a few hundred thousand years from now, and prefer
that it continued to exist. It's probably a good bet
that our descendants would not want the planet ruined by
haphazard physics experiments conducted by their ancestors. I imagine the

rest of life on Earth would have similar feelings on
the matter too. But what if Hawking was right and
microscopic black holes do evaporate, It could still pose an
existential threat because in evaporating microscopic black hole could give
a low energy vacuum bubble from the Higgs field just

the boost it needs to grow and ruin the universe.
If we can rewind back to the moment in the
LHC when those two particles collided head to head at
amazing speeds and they're concentrated gravity overlapped, Let's say that
the microscopic black hole they produced didn't grow up to
tear Earth apart, but instead it evaporated, just as Stephen

Hawking predicted. As it evaporated, it could become the nucleus
for a low energy vacuum bubble to grow, in a
very similar way to how tiny impurities in a metal
pot become the places where water can undergo a phase
transition from liquid to gas within itself. This is what
we call forming a bubble. An evaporating black hole could

serve as a nucleation site for the Higgs field to
undergo a transition from its current state to the lower
energy version of itself, which again would bring about vacuum decay,
the ultimate ecological catastrophe, which, again, at the risk of
restating the obvious, would be very bad for the current

arrangement of our energetic vibrations. This would not take a
few hundred thousand years to notice. It would happen so
fast that we likely wouldn't notice we just suddenly be gone.
So we have then at least two possible catastrophic outcomes

from the creation of man made microscopic black holes here
on Earth. And what's unsettling about them is that there's
a catastrophe for each possibility. Where Stephen Hawking was either
right about evaporating black holes or where he was wrong.
Take your pick. One day in two thousand and eight,

a bird that lived in the countryside along the border
between Switzerland and France found itself a bit of crusty bread.
Around that same time, one of the electrical supply stations
that cools the Large Hadron collider's magnets with liquid helium
suddenly went offline. When workers went to investigate, they found
a bit of crusty bread and some feathers. The press

reported on it, took liberties with it, and that story
grew to enormous proportions. Words spread that a single bird
with some baguette had knocked out the Large Hadron Collider,
the fastest and largest particle collider on Earth. A pair
of theoretical physicists named Hulger Nielsen and Massao Ninomia had

been taking note of the accidents in weird setbacks like
this that plague the LHC as it was being built.
They had come to believe that something, possibly God, was
reaching back from the future two sabotage the Large Hadron
Collider and prevent it from ever reaching full power. It

might mean that the LHC would create something, the physicists said,
that could destroy the universe. They took the bird in
the baguette as further evidence for their hypothesis. Nielsen and
Ninomia proposed issuing a challenge to the future to determine
if we should shut down the Large Hadron Collider and
abandon it forever. We could present the LHC with some

luck of the draw, maybe something like ten million cards,
all of them hearts, except one, just a single spade.
And if we asked the Large Hadron Collider to pick
a card, and the Large Hadron Collider picked that one
single spade, an extraordinarily unlikely event, then the particle physics
community should take it as a sign that the future

was communicating a warning to us. Sir, never took the
physicists up on their card draw proposal. Nielsen and Ninomia
suspected that the future was trying to prevent the Large
Hadron Collider from creating a Higgs boson, that particle that
gives everything that has mass mass. It was widely hoped.

In fact, it was largely the reason it was built
that the LHC would produce the Higgs boson, which again
was the last undiscovered particle predicted by the standard model.
And in two thousand and twelve, the Large Hadron's computers
found something that had been created for a fraction of
a fraction of a second inside the collider that fit
the parameters for the Higgs boson. There was no catastrophe,

The world didn't end, and to an extent, the discovery
of the Higgs frustrated physicists even more since it further
supported the stubbornly accurate Standard model they've been hoping to break.
But finding reassurance in the survival of the universe after
the successful creation of the Higgs boson in the LHC
is actually a logical fallacy. Specifically, it produces what's called

the normalcy bias. We tend to assume that because no
catastrophe has befallen us, yet none will. It's the same
false belief that drives investors to buy stock based on
past performance. But any financial advisor worth their salt will
tell you there is no certainty about the future to
be found in the past, and so too will a

particle physicist tell you that. One of the tenets of
quantum physics is that there is no such thing as certainty.
We are incapable of certainty. Instead, particle physicists deal improbability.
As one certain physicist explained it to me, you can,
for example, take the number of times that a car's

engine has ever been started and calculate the probability that
the next time you start your car it won't create
a chain reaction that ignites Earth's atmosphere. What you have,
then is what's called the lower bound probability that it
would happen in an odd, roundabout way. When cars were
first invented, they actually had a higher probability of igniting

the atmosphere compared to cars today, simply because fewer cars
had ever been turned over back then. The large Hadron
collider is in a similar position with the LHC. We
simply have a smaller data set from the fewer times
that it's been turned on. This is in a perfect analogy,
though there aren't any quantum theories that suggest a car

could ignite the atmosphere, like there are that suggests the
LHC might be capable of creating a black hole or
a strange lit But ironically, the more times we press
our luck and run the LHC, the lower the probability
that something terrible will happen. Get the thing is, no
matter how many times we run the Large Hadron Collider,

we will never be certain that something terrible won't happen.
This is the curse of the universe that quantum physics
carries with it. We are doomed to uncertainty. Eight white
dwarfs still hang in the sky, but we still can't
be certain that one of them won't begin to come
apart tomorrow from the microscopic black hole growing within it.

It's a matter of faith, faith, and probabilities when it
comes to the existential safety of physics. Uncertainty curses. All
of us physicists face a dilemma when they talk about
the safety of their work to people like you and me.
The general public. If they speak openly about it, they

may cause a panic and possibly even undermine their own
field of research. If they don't, they appear like they're
hiding something. Here's physicist Daniel Whiteson again. And I think
the reason is that they don't believe that there's a
lot of and that there's a lot of numerous e
in the public and in journalism, and that a nuanced

position where you're saying, um, there's no none of the
threats we understand are significant. However, there's a possibility of
a thing we don't know that we hadn't considered that
could of course destroy the world, but you know that's
unlikely and unknowable and so not something to consider. That
kind of nuanced position, I think it is very difficult

to convey. So physicis systs may decide that the general
public can't really understand probabilities, and we'll stop hedging when
they speak about the safety of their work, erasing those
remote possibilities of catastrophe and presenting a full certainty that
particle physics is perfectly safe, that there is no risk.

This is a dangerous position when it inevitably comes out
that there is in fact a risk and that scientists
are well aware of it. Trust is lost in the
very people who carry out existentially risky experiments, and the
most sensational and unfounded stories start to gain traction among
the general public. And it's also directly a dangerous position

as far as existential risks go, because existential risks are
by definition remote. They are the risks that get erased
when physicists speak with certainty about the safety of their work.
But as you know by now, those same existential risks
are the ones that can erase humanity should the ability
surrounding an experiment suddenly skew towards the remote Unexpectedly. Pretending

those risks are not there is the most dangerous route
we can take. But scientists who do have the integrity
to admit that they can't be certain their field doesn't
pose existential risks frequently find that they're misquoted or misrepresented
in the media, which can lead to them being ostracized

by their colleagues for stirring up problems for the field.
So they may become defensive, which is never good for
keeping lines of communication open. But I think the experience
of a lot of scientists is that they say Oh,
that's very unlikely, but of course possible. And then they
read an article where they say certain scientists says end
of the world possible, you know, and so it's it's um,

I think you're right that they're defensive, but I think
that comes from some experience and some caution about the
level of the discourse in the public arena. It is
with this in mind that CERTAIN is to be commended
for working to show that the large Hadron collider is
a safe machine, even considering that it was a reactive
procedure rather than a proactive one. CERTAIN is a great institution,

and one thing that I admire so much about them
is how open they are. And much of what I
was able to do in my research is thanks to
them being very open. They're very very open in terms
of sharing their data, sharing their papers, being accessible in
terms of talking to them. That's part of what makes
me admire them so much as an academic myself. I

just think that that's a great model for building and
sharing knowledge, and it's to their credit that they have
looked at these issues with a great deal of transparency.
It is extremely important that the physics community follows CERN's
lead and its willingness to investigate the safety of its
work has their experiments grow more and more powerful in

the future. There's a different interpretation to the cosmic ray argument,
a more nihilistic one. It says that the presence of
cosmic rays doesn't prove that particle colliders are safe. It
just shows that our particle colliders can't make anything more
precarious than they already are. Turning on a particle collider
is safe because we can't turn cosmic rays off, so

we're not going to be causing any new danger by
turning them on. But what about some decades or a
century from now, when our experiments begin to reach levels
that exceed cosmic rays. If the Large Hadron Collider is
an early incarnation of a long line of particle colliders
to come, as physicists hope, there will likely be a
point where the energies of future colliders rub up against

and then eventually exceed, the energies of cosmic rays, the
very same cosmic rays that we use today as some
sort of proof that our colliders are safe. And over time,
as physicists develop a greater mastery over the rules of
our universe, particle colliders may transition into laboratories that physicists
use to bend the laws of physics to their will.

Those nearly blind pokes and prods into the darkness of
our understanding that physicists today carry out are providing the
body of knowledge that physicists to come in the future
will build upon. And if humanity can survive our infro
to physics, a tremendous amount of promise lies in store
for us from it. An odd thing about the universe

has been bothering physicists for a while now, and it's
something that the discovery of the Higgs didn't help. It
seems more and more that our universe appears to be
finely tuned to allow for life to exist. The Higgs field, gravity,
all of it is right within the narrow bounds that
allow for atoms, chemistry, and life. When the Higgs boson

was finally founded two thousand twelve, it appeared right in
the very middle of where it was predicted, as perfectly
finely tuned as the rest of the fundamental particles. One
answer to the strange situation is that our universes finally
tuned for life simply because of random chance. There's a
remarkable implication of string theory, one of those theories that

seeks to unify gravity with the quantum forces. String theory
says that if you take all of the particles and
forces and dimensions that the theory predicts, you can come
up with ten to the five power different possible combinations
among them. If you consider each of those combinations as
a set of rules for a potential universe, including the

combination that governs our own universe, then you have as
many possible universes as ten to the five power. Our
universe just so happens to be one with the combination
of those dimensions and particles and forces that allow for life.
That's the basis of what's called the anthropic principle. The

kind of universe where life could evolved is the only
type where we would find ourselves wondering about why things
seem so finely too fine tuning may really not mean
anything at all. By learning about the reality of our universe,
physicists will answer questions like this, and when they do,
they will be able to do amazing things like predict

anything that could possibly happen with absolute accuracy, and perhaps
future physicists will learn to construct new universes within their
particle colliders grow them from seat. Exactly how we may
someday be able to do this has already been roughly
sketched out, and now the data must catch up to
the theories. To some people physicists creating new universes where

life might arise organically, it's actually a dreary sad idea.
Any universe we might create in the lab would almost
certainly have its own space time, and so it would
be totally detached from our own universe, And so those
physicists who created that universe would have no way to
alleviate the profound suffering that life in that other universe

might experience. To people who believe that the purpose of
life is to reduce suffering, creating a universe like this
would be a profoundly irresponsible act by a creator God
with no power to interview. But there is also a
tremendous amount of promise in the idea of lap grown universes.

Perhaps we will be the life that populates them. Perhaps
future humans will be able to grow new universes to
move into when our universe begins to expire. Perhaps, unbeknownst
to us, those physicists of the future will be carrying
out the same kind of experiments that produced our universe,

or perhaps they will be creating our universe. For phaps,
that is how we will make our escape back to
the beginning. Perhaps that's what we've always done. On the
next episode of the End of the World with Josh Clark,

the future is what's called a transgenerational global commons. We
share it not just with everyone alive today, but everyone
to come as well. And for the first time in
human history, it is in the power of those of
us alive to save it or destroy it permanently. And now,
if you think about what the existential risk mitigation is,

not all that is it the global public good existential
risk mitigation, but it's also of transgenerational public good. But
to take on the existential risks we face, we will
have to overcome our own worst impulses.

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