Cindy Kelly: I’m Cindy Kelly, Atomic Heritage
Foundation.
It is Wednesday, April 25, 2018.
I have with me Tom Cormier.
First question is please say your full name
and spell it.
Thomas Cormier: Tom Cormier, C-o-r-m-i-e-r.
Kelly: Perfect.
Okay, my first question to everybody has been
to tell me a little bit about yourself, where
you’re from, when you were born, your education
and how you came to be a scientist.
Cormier: I grew up in the suburbs of Boston
in the town of Lexington, which is a very
historic area in its own right.
Growing up there, I was surrounded by people
who in that community lived and worked in
and around Boston in many of the big universities
in the Boston area.
In fact, a lot of the neighbors on my street
were from MIT [Massachusetts Institute of
Technology] and so forth.
My father, who was very interested in science
but was not a scientist – he was kind of
an engineer, a hands-on sort of a guy.
He always talked about physicists, even when
I was very young.
Because he grew up, of course, through the
period where, from his perspective, physicists
helped with the existential crisis of World
War II.
So he was very impressed with physicists,
and he would always talk to me about them.
Although he really understood almost nothing
from a fundamental point of view, he really
wanted to hear about it all the time.
I sort of researched things.
I can remember even being very young researching
things and trying to help explain it to him.
Finally, when I got older, I just went to
my neighborhood school, which was MIT.
And the rest is sort of history.
By the time I arrived at MIT – which was
1967 when I first arrived there – every
significant university in the United States
had a burgeoning program in nuclear physics
already.
It was something that also grew out of the
Manhattan Project.
It had sent its roots into the university
system in the United States.
Virtually every university in the United States
of any size had its own particle accelerator
in those days.
As an undergraduate, you were invited to get
your hands into the physics and work with
these machines that were all over the place.
Of course, over the years, those machines
were turned off gradually, and the science
got bigger and bigger and bigger.
Until finally, you don’t find the kind of
science we do anymore on a university campus,
that’s for sure.
The science has sort of outgrown that.
But I’ve been attached to it right from
those early days.
Kelly: What happened next between MIT and
ORNL [Oak Ridge National Laboratory]?
Cormier: I had the usual few post-doc positions.
I spent a year in Germany at the Max Planck
Institute.
Then I got my first faculty position and,
as often happens to young assistant professors,
the way you get promoted is by moving to another
university.
I had tours of duty at several places, until
finally I had become a senior professor and
got invited to join the faculty as a department
head.
Worked as a department head for a number of
years, until finally a position opened up
here for a new group leader to give the effort
in the kind of physics that I was doing, called
heavy ion physics.
I’ll have to explain why in a bit.
But there was an opening for a leader in that
area here at ORNL to rejuvenate the effort
and give it a new focus, and so I thought
it would be interesting.
I was, at the time I came here, probably officially
past the retirement age, let’s say.
I was looking forward to working for, whatever,
five, six, seven years or so and taking this
challenge of instituting a new program and
seeing what we could do with it.
Kelly: How many years has it been?
Cormier: It’s been five years so far.
I would say we really accomplished most of
what we set out to do in that period.
I’ve hired a lot of new people and built
up the group, as you know, at CERN [European
Laboratory for Nuclear Research], and got
the necessary rules waived to allow us to
site our people at CERN.
The group, literally, is in Geneva, Switzerland,
although I’m here most of the time.
One week a month, roughly, I go to Geneva.
Kelly: Can you describe in very simple, layman
terms what it is that your group is involved
in?
Cormier: Right.
We use the Large Hadron Collider at the CERN
facility.
CERN is the European Center for Nuclear Research,
and all the European countries come together
there to conduct their research in this field,
elementary particle physics and high energy
physics.
By pooling their resources, they’re able
to build an impressive facility, a world-class
facility.
It’s said to be the largest physics laboratory
in the world.
Today, not only Europeans come there, but
also a very substantial number of Americans,
for instance, and Asians come there to do
their work.
The kind of experiments that are mounted on
the Large Hadron Collider typically have thousands
of collaborators.
The ALICE [A Large Ion Collider Experiment]
experiment that I’m part of has about 2,000
collaborators.
That is, when we publish a paper, it has 2,000
names on it as the authors of the paper.
It’s a significant undertaking.
The other experiments are even larger than
that.
In fact, there’s some that are approaching
5,000 authors, I think.
It is definitely Big Science.
Obviously, this doesn’t fit on a university
campus anymore.
In fact, it almost doesn’t fit in more than
one place in the world.
The whole world comes together to do this
in one place, and that’s what CERN is.
At this facility, what we do is we collide
elementary particles.
My specialty is colliding whole nuclei.
Whole lead nuclei, circulating around this
accelerator in opposite directions at really
unprecedented energies, are brought into collisions
as a means to produce tiny samples of ordinary
matter, heated to trillions of degrees Centigrade
and compressed to hundreds of times the density
of normal nuclei, to essentially turn back
the clock.
This tiny sample of matter is similar to,
it turns out, what the matter that made up
the universe was like when the universe was
only a few microseconds old.
Basically, using that facility, and those
special ions, gives us a window into the nature
of the matter that filled the universe when
it was only a few microseconds old.
To push further back than that, to try to
push back right to the very beginning, is
essentially impossible, because the laws of
physics are unknown to us under those conditions.
But this time window, which begins at a few
microseconds after the universe began, is
essentially something we can understand with
the current laws of physics as we understand
them.
And an area where we can actually make observations
of the matter by, as I say, running back the
clock through these collisions.
Kelly: Why don’t you tell us a little bit
about the most famous recent discovery, the
Higgs boson.
Cormier: Yeah, the Higgs.
The Higgs is an amazing discovery.
As you said, it’s one of the few examples
in physics where you built a facility and
then, within the first year of operation,
you’ve won the Nobel Prize with the three
scientists to who it was awarded.
That doesn’t happen very often, I’ll tell
you, that thousands and thousands of people
came together to build that machine, and it
was a very single-minded effort in that sense.
There was one thing that everybody was striving
for, was to see if this particle existed.
Because it was a missing link, essentially,
in the theories that underpin our understanding
of matter.
The theorists told us it had to be there.
If it wasn’t there, then our understanding
was really incomplete in some very fundamental
way.
So it was worth the – I don’t know, five
to ten billion dollars that were spent to
accomplish that result in the end, to build
the biggest machine that has ever been built
anywhere by human beings.
And to operate it during the first year in
a way that gave positive evidence for the
existence of the Higgs boson.
What the Higgs boson does in the theories
that describe it is rather complicated, but
what it does is it gives everything mass.
Without the Higgs boson, all the particles
that we understand in the universe, all the
atoms that we see around us, they would be
massless.
And it wouldn’t be much fun.
Finding the Higgs was really important to
having everything hang together.
All the bits and pieces that make up the stuff
around us, that it has any substance at all,
is really due to the Higgs boson.
It’s there, and in fact it’s amazingly
simple once you see it.
It stands out, it’s obvious, and was just
out of reach for all these years until we
built a machine big enough to find it.
Kelly: It’s so interesting.
As a souvenir there, I bought a coffee cup
that has a simplified version of the formula.
I mean, it makes it look very simple.
Cormier: Right, yeah, it’s—
Kelly: And no, it’s not.
Cormier: It’s not simple, no.
Kelly: I know it’s not.
Cormier: In fact, I think what you’re talking
about is the QCD [quantum chromodynamics]
Lagrangian, is what it’s called.
In fact, you can write it down, but you can’t
actually solve it in detail, because it’s
a highly what a mathematician would call non-linear
formula.
There’s no way to actually solve it exactly.
Now, we can solve it approximately in computers,
which is what the theorists do these days,
but it’s a beautiful formula.
But basically too complex to really figure
out with a pencil and a paper.
The people who did the experiments to discover
the Higgs and so forth are really working
in somewhat different fields from me.
They collide protons and it makes all the
difference in the world whether you collide
two protons –– which are the smallest
pieces of matter than you can isolate, ordinary
matter that you can isolate, –– or the
things that I do, which are to collide full
lead nuclei and start with a large sort of
macroscopic sample of matter.
The people who studying the Higgs are looking
for the next piece of the puzzle, which would
be if there were more examples of the Higgs
boson.
Is it really only one, are there multiple
Higgs bosons?
Because those are variations of the theory,
which would make the universe behave quite
differently.
This exploration of the so-called Higgs sector
is looking for the kinds of physics that might
be hiding in the neighborhood of the Higgs.
What this takes –– so as I said, we discovered
the Higgs in one year –– what this takes
now is many years’ investment, studying
in much, much greater detail, the kind of
events where the Higgs shows up.
But looking to see what else is going on,
maybe at a one part in a thousand or one part
in a hundred thousand kind of level and digging
deeper and deeper into the details.
That’s good, old-fashioned, roll-up-your-sleeves
kind of science, and that’s what’s going
on now.
Kelly: That’s what they’re doing.
Cormier: Yes.
Kelly: But what you’re doing—
Cormier: Yes.
We collide lead nuclei, which is something
that CERN does one month a year.
It’s actually possible to distinguish it
by saying what the people who are colliding
protons are doing are studying elementary
particle physics, the physics of the elementary
constituents of nature.
Whereas, what the people who collide lead
nuclei are studying is an extension of nuclear
physics into this ultra-high energy regime.
So one month a year—the accelerator runs
for about seven, eight months a year—and
so for 10, 12, 15% of the time, it does nuclear
physics.
For the rest of the time it does elementary
particle physics.
The program of studying the nuclear physics
is what I began my dissertation with here,
which is to study the matter of the early
universe.
By colliding two lead nuclei at these fantastic
energies, you create not a point-like object,
which is what you get when you collide two
protons, you create something that actually
has a finite volume.
A nucleus may not be very big, but compared
to a proton, it’s gigantic.
What we do is we take a sample of matter the
size of a lead nucleus and heat it, as I said,
to trillions and trillions of degrees, until
the matter melts into a soup, which is very
much like the early universe in the first
few microseconds of its existence.
Then, our detectors help us study the properties
of that matter and observe it as it expands
and cools and turns back into ordinary matter.
We can trace it from the instant of the collision,
where the temperature goes from essentially
zero all the way up to trillions and trillions
of degrees in the collision, and then watch
the collision come apart in our detectors
as the matter cools back down.
And can watch the transitions that it goes
through, the same transitions that the early
universe went through, where the early constituents
of the universe was this soup of quarks and
gluons at very, very high temperature, which
expanded.
The universe expanded through its first moments
of existence, and as it expanded it cooled
in the same way that our little mini-bangs
expand and cool when we perform the collisions
at the Large Hadron Collider.
So we can study how ordinary matter reappears.
You start with these collisions, they create
the matter of the early universe, and then
study it as it reemerges as ordinary matter.
What kind of matter is made?
Do we make the protons and neutrons, for instance,
that make up everything around us today appear
in our collision?
We start with matter, heat it to trillions
of degrees where there are no protons and
neutrons –– there are only quarks and
gluons –– and then we watch it cool and
expand.
We watch the protons and neutrons emerge,
again, from this hot soup, just the way they
did from the early universe.
It is really an experimental probing of how
the universe behaved in that first few microseconds,
which we can then compare with the theories
of the early universe.
Now, these theories of the early universe,
obviously, are very closely coupled to our
other colleagues at the Large Hadron Collider,
because this is a world that was full of elementary
particles.
You have to know how elementary particles
behave.
I shouldn’t have given the impression that
we only work one month a year when we’re
running the lead beams.
We have to understand the collisions of the
protons as well.
It’s an important ingredient in understanding
how those protons emerge when we study them
with the lead collisions.
It’s a full seven, eight months a year that
we’re doing physics in Geneva.
Kelly: That’s fascinating.
So your team is actually collaborating with
members of other teams that are dedicated
to the particle physics.
Do the particle physicists bring in members
of your team, or is it a bilateral ––
Cormier: It is.
All of the experiments – there are four
experiments on the Large Hadron Collider.
They are sited at locations where the beams
intersect.
The Large Hadron Collider has a circumference
of about 21 kilometers, and as the beams go
around that enormous ring, they collide at
four different locations.
At those locations there are these enormous
experiments, and each of them studies the
physics of these collisions from a slightly
different perspective.
That is, the detectors differ in the way they
perform their observations, the kind of things
that they measure.
There’s a coherence in that the underlying
physics is the same, but everybody’s looking
at it in a slightly different way.
There’s a very strong sort of cross-breeding
between all the experiments and all the collaborators.
One of the things I do sort of in my spare
time is I’m on the so-called ALICE thesis
committee.
We have, as I said, about 2,000 collaborators.
Among those collaborators are hundreds of
PhD students and those PhD students write
their PhD theses.
There may be as many as 50 PhD theses produced
per year, just from the ALICE experiment.
Then the students are invited to submit their
thesis to be judged for the annual prize that
goes out for the best thesis in ALICE.
I’m one the guys who has to read all of
those submitted theses.
This year, we have twenty PhD theses, so that’ll
keep me busy until about July.
Kelly: Do you actually meet with the scientists,
or just read the papers?
Cormier: No, we know most of them.
The young people are really the heart of the
experiment, they do all the work.
They are – you can’t miss them.
They are there in the ALICE buildings and
they are underfoot.
They’re there and you know them well, and
you know their work, you’ve known them for
the three or four years that they’ve been
doing it.
They’re well-known to us.
It always comes down to a difficult choice.
We have a committee, I think, of probably
eight people this year who will look at these
twenty or so theses that are submitted and
try to judge the best one out of the bunch.
It’s a difficult job.
And again, every thesis is a little different.
A PhD thesis asks a question, basically, and
then the author of the thesis tries to convince
you that he knows the answer, or she knows
the answer.
Everybody has a different take on it, and
so it’s quite interesting to see how the
young people are sort of continuing this kind
of tradition of nuclear physics.
But now on such a mega scale that when I was
a student, it would have been inconceivable
that you could have a machine this big and
you could actually make it work.
Never mind make it work, but just imagine
collaborating with a thousand people and getting
anything done.
Getting that paper written when there are
a thousand authors is a task in itself.
Kelly: Staggering.
Goodness.
On top of that, you’re dealing with, I’m
sure, people from every nationality.
Cormier: Oh, yeah.
In ALICE, there are, I think, represented
about fifty to seventy separate national funding
agencies, for example.
It operates a little bit like a United Nations,
a mini United Nations, to make all of those
people focus on the same idea and cough up
the money to support their share of it.
The Department of Energy is one of the participants
in that.
They fund our work explicitly, but they’re
also stakeholders and they contribute to running
the experiment.
It is a little bit like the United Nations,
figuring out how much is your share and how
much is my share.
Within that group of fifty to seventy or so
national funding agencies, there are some
that are dominant.
They simply are the largest participants.
They include the ones you would guess, probably:
the United States and the major Western European
countries and Russia and China, of course,
and Japan.
Basically all the countries that have very
vibrant economies can sort of afford this
kind of science.
They tend to be leading groups in all of this.
But every country, virtually every country
is represented at some level, even if it’s
only a single person.
Azerbaijan is there, for instance.
They have one student who is part of the collaboration.
You’re right, every nationality is represented
at some level, and some nationalities are
more dominant, of course.
As I said, they tend to be the ones that come
from the countries with very strong economies
and can kind of afford it.
It makes it – the common language in all
of the scientific communications is English.
But if you’re in the experiment, you’re
hearing Italian and German and French spoken
sort of simultaneously.
It takes a little getting used to, actually,
all that background noise in five different
languages all at the same time.
The scientific communication is in English
and the papers are written in English.
There was some debate, probably very early
on, when CERN was first formed, whether it
should be English or French, but English won
out.
I think official CERN communications are still
in two languages.
That is when they send out some political
document, the top half is in English, the
bottom half will be in French.
But all of the real scientific discussion
is in English.
Kelly: Which is a big advantage for Americans.
Cormier: Oh, yeah, really.
Because if I had to survive on my French,
we’d be in trouble.
Kelly: I’m just curious about the number
of women who might be involved in CERN work.
If you don’t know precisely, what’s your
impression?
Cormier: No, I don’t know precisely, but
I’ll tell you there are some interesting
trends that you can observe.
For instance, women are a substantially larger
fraction of the scientific community at CERN,
if you look at the collaborators who come
from France, for example.
Same is true of Italy to some degree.
Women in Italy tend to gravitate more toward
physics than women in the United States do,
for example.
I’m trying to think.
In the full U.S. team, not just Oak Ridge,
but the full U.S. team consists of about –– well,
it varies from year to year because the students
come and go, but there may be 100 U.S. participants
in this experiment.
I’m going to guess that there are less than
five or ten women in that group from the United
States.
Whereas, the fraction for the French group
might also be 100 people, but they’d be
closer to half women.
So, it’s really a big ––
Kelly: That’s astounding.
Cormier: Yeah, it is.
Kelly: So Marie Curie lives on.
Cormier: Yeah, I think, in fact, there’s
an influence of exactly that.
That’s right.
Kelly: What do you think the future holds?
Cormier: This is a big topic of discussion,
of course, because the Large Hadron Collider
took approximately twenty years to realize.
The planning for it started twenty years ago.
The building of these big experiments takes
ten to fifteen years, even once you know what
you’re going to build.
You need to get the funding in place and so
on and so forth.
It’s a twenty year commitment to getting
this machine running.
The planning for what comes next started quite
some time ago already.
There are a number of options on the table.
It doesn’t cost a whole lot of money to
explore options, but once you select one,
then it gets expensive.
There are options.
There is the so-called Future Circular Collider.
The Large Hadron Collider, as I said, is a
circle about 21 kilometers in circumference.
The Future Circular Collider would be about
ten times bigger than that.
It would cover a substantial fraction of the
western end of Switzerland and that region
of France, and would have an energy that would
be ten times higher than the current energy.
There are other ideas, however.
There’s the so-called Compact Linear Collider,
which is where you basically give up on the
idea of running beams in a circle, so that
you can reuse them.
But rather make accelerators that are linear,
straight lines, and they simply just shoot
particles at each other.
You can have a machine that maybe is 100 kilometers
long and the beams come at each like the bullets
from two guns traveling in opposite directions
and you have collisions like that.
Each of these approaches has their own team
pushing for them.
R&D is going on in both kinds of futures.
But again, these are facilities that are so
big –– we’re talking now ten times the
scale of what has just been accomplished –– that
this really now takes complete involvement
of the whole world.
Whereas the U.S. participation in the building
of the Large Hadron Collider was at the level
of some percent, probably, of the total budget
for the thing.
Although there were very significant technical
contributions from all the national laboratories,
for example.
It would take from the major economies of
the world far more substantial investments
to realize now a facility which is ten times
the size of the one that we have now.
All the usual problems then have to be worked
out.
Where are you going to build it, first?
The Japanese would like to have it in Japan,
for example, and U.S. senators would like
to see it near Chicago.
Those discussions will go on forever, and
at the end of the day, the country that comes
up with the most money probably has the most
to say about where the thing gets built.
The future is – because the lead times are
so long on these projects, people are already
thinking about what will happen now ten years
from now, twenty years from now.
I think there’s one thing I would say just
to sort of frame this kind of work.
It’s a little bit different from a lot of
the science that your typical high school
student may think of when he or she thinks
of science.
They think of the chemistry laboratory, behind
the little door and so on and so forth.
This is truly Big Science.
This is science of the scale of the Apollo
lunar landings, for instance, which was undertaken,
of course, entirely by the United States.
Now science of this size is of such a scope
that it really needs to be undertaken by the
whole world together.
That’s an important part of this, I think,
and that attracts some people to it.
It pushes some people away, because they just
see it as so much chaos.
There are long periods of chaos, there’s
no doubt about it.
But in the end, when it all comes together
and works, it’s really quite impressive
that you can really get that many people moving
in the same direction.
It’s an exercise, really, in sociology as
well as science, which is kind of fun.
Kelly: People talk about can we have another
Manhattan Project, and World War II was such
a galvanizing force ––
Cormier: Right, exactly.
Kelly: Right, and you had all the prima donna
scientists that [J. Robert] Oppenheimer had
to corral.
Some of them were a little wayward, but most
of them were very focused.
Cormier: Right.
Kelly: But that’s very hard to recreate.
Cormier: Right.
That’s exactly right, and there’s an interesting
outgrowth of that.
What I call Big Science actually begins – well,
the first example of that is the Manhattan
Project.
Because prior to that, governments around
the world did not invest in science at all.
You had private foundations or universities
or whatever investing in science, and that
really limited the scope of what you could
do.
But after the Manhattan Project, it became
clear that the way to really get things done
is to put the backing of major governments
behind certain scientific initiatives.
Then you can see what –– you can land
on the moon, you can build the Large Hadron
Collider.
That really begins with the Manhattan Project.
This whole idea of government investing in
science really came out of the Manhattan Project.
