Raymond Laflamme on the life-changing power of curiosity

Raymond Laflamme was the founding director of the Institute for Quantum Computing at the University of Waterloo, a position he held for 16 years, and he has been an associate faculty member at Perimeter Institute for more than two decades. He is known as one of the world’s leading experts on quantum information science, and was recently appointed as the chair of the Expert Panel on Quantum Technologies assembled by the Council of Canadian Academies. In this conversation with Lauren and Colin, Laflamme explains the incredible potential power of quantum technologies, and what drew him back to his native Canada to pursue research in the field. He shares how his life and career were influenced by his famous PhD supervisor, Stephen Hawking, and how his insatiable curiosity kept him motivated during his recent battle with lung cancer. View the episode transcript here.

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Conversations at the Perimeter is co-hosted by Perimeter Teaching Faculty member Lauren Hayward and journalist-turned-science communicator Colin Hunter. In each episode, they chat with a guest scientist about their research, their motivations, the challenges they encounter, and the drive that keeps them searching for answers.

The podcast is produced by the Perimeter Institute for Theoretical Physics, a not-for-profit, charitable organization supported by a unique public-private model, including the Governments of Ontario and Canada. Perimeter’s educational outreach initiatives, including Conversations at the Perimeter, are made possible in part by the support of donors like you. Be part of the equation: perimeterinstitute.ca/donate

Episode Transcript

(00:00):
(gentle electronic music)
- Hi, and welcome to"Conversations at the Perimeter."
Today we're excited to sharewith you this conversation
with Ray Laflamme.
Ray is a researcher at theInstitute for Quantum Computing
and the Perimeter Institute,

(00:21):
and he's an expert on everything related
to quantum information.
- I was so excited to havethis conversation with Ray.
I've been looking forwardto it for a long time
'cause I've known Ray for about12 years 'cause he hired me.
He was my boss at theInstitute for Quantum Computing
when I worked in communications,
and he's really responsible
for teaching me the things I first learned
about quantum computing

(00:42):
by showing me around andtaking me to the labs.
And his passion and his dedication
to the science is really infectious.
And as you'll hear, he'sa wonderful storyteller.
And he told us stories abouthis early days studying
under Stephen Hawking at Cambridge
and then working at LosAlamos National Laboratory
and then more recently, hisstruggle with lung cancer

(01:04):
and how that's shaped his perspectives
on life in the future.
- I really loved hearing his stories
about how quantum computing
and quantum technologyhas evolved over the years
and also what we canexpect for the future.
So let's step inside theperimeter with Ray Laflamme.
- Ray, Laflamme, thank youso much for being here.
It's great to see you.

(01:25):
- You're welcome.
- I wanna start with a big question.
How's life?
- Life is really good.
Definitely after a pandemic of two years,
life seems to pick upagain of seeing people.
And then I think that pandemichas made us enjoy the kind
of precious moment evenmore than we did before,
realizing that there are things

(01:46):
that goes in different ways as life goes,
and then you adapt to them,
and then suddenly you realizekind of what are the diamonds
that kind of before, youwere kind of neglecting.
- This is part of the reason
I was so excited to talk to you.
I've known you now, I did the math,
I think it's been about 12years since we first met
because you hired me to work
at the Institute for QuantumComputing in Waterloo,
where you were the director.

(02:07):
And I still remember thefirst thing you said to me
on the first day of the job.
I bet you don't remember this.
I remember it clearly.
I walked into your office.
You said, "Hello," andyou said, "Lose the tie,"
because I was wearing a tie.
And I thought, "Oh,okay, I like this guy."
And then you were such a mentor to me.
I had come out of a journalism career,
and I knew practically nothingabout quantum computing

(02:28):
and quantum information.
So you showed me around this Institute
for Quantum Computing.
Could you tell ourlisteners what the Institute
for Quantum Computingis, how you got involved,
and what it's for?
- The Institute for QuantumComputing is an Institute
at the University of Waterloo
whose aim is to develop thescience of quantum information.
And that includes quantumcomputing, quantum communication,

(02:51):
quantum metrology, or quantum sensors,
and some materials that are essential
to build devices thatuse quantum mechanics.
So it's an institute whose firstgoal is to do the research,
the basic research relatedto quantum information,
the second one to traina generation of students

(03:11):
and scientists andengineers who think quantum.
We all kind of grow up,
and you are learning Newton's mechanics
or classical mechanics.
Even if most peopledon't call it that way,
that's the way we understandhow to control our car,
using our bicycle or whatever,flying in an airplane.
But really, the world

(03:32):
at its very fundamentalpart behaves differently,
like atoms and molecules and electrons
and protons has a different set of rules.
And then we want to use these rules
to manipulate information.
- Could you give usmaybe an example of one
or two of those uniquely quantum rules
that you're trying to exploit

(03:53):
and why harness these properties?
- I'm happy you say why harness these
instead of why do they behave that way
because we just don't knowwhy they behave that way.
The world is built in some way,
and maybe there's a fundamental reason
that one day we will discoverthat it cannot be otherwise.
It had to be this way.

(04:14):
But right now, we justkind of explore the world
and try to understand how it works
and not necessarily why it works that way.
So one of these propertiesof quantum mechanics
is called the superposition principle.
In the physics of Newton orwhat I call classical physics,
we think of objects made of particles,

(04:35):
and particles are little things
that are at a given position in time
and at a given velocity.
This works very well todescribe most of the world
that we interact with in day to day,
except people like me and my students
and my colleagues who suddenly go in labs
and isolate these particles very well
and try to see how they work.

(04:56):
And what we find is there's something
called a superposition principle.
These fundamentalparticle of nature can be
at more than one place at a given time.
So a single system can be hereand there at the same time.
We are trying to use this property,
the superposition principle,and use it to compute.
And so we kind of discovered

(05:18):
that if we use these properties,we can build computers,
or we are attempting tobuild these computers.
We're still kind of early in that stage.
Although we have somereally good prototypes
that shows that the science is okay
and kind of things are working the way
that we're thinking they should work.
And so we found that by using the rules
of quantum mechanics,
the theory that describedthis kind of very small part

(05:41):
of the world,
if we use the rules ofquantum mechanics to compute,
we can solve problems whichseems to be intractable
with classical computers.
And suddenly it tells usthat if we can do that,
there's a wild world of information
that will open to us that we haven't,
which is totally surprisingbecause it is mind-boggling

(06:06):
what we've seen in the last50 years with the computing
or information revolution.
Before people werehaving to jump on a horse
to tell the story to somebody else
in the 16th, 17th, 18th century.
And suddenly people invented the telegraph
where we can send things,short waves to send messages.

(06:28):
This turned into computersin the 1970s and '80s
and to cellular phone that we have today.
When we look at our kids,
if you want to give them a hard time,
you take their cell phone off.
It's like the end of the world,like they cannot connect.
You and me have grown upwhere we had neighbors,
and our friends were neighbors.

(06:48):
Our kids grow up where theirfriends can be in France
or in Japan or in South America.
Instead of having a little local village,
the earth is a global village,all putting this together.
That changed the way thatpeople think, how we behave,
and what we think about the future,

(07:10):
so this incredible changeof how we conceive the world
because of this information revolution.
And suddenly quantum mechanics comes in
and tells us things canbe very, very different.
We can evaluate even somuch more information
that these classical computers cannot do.
So, there it is.
And this is what the Institutefor Quantum Computing,
I would say the Perimeter also,

(07:31):
are investigating these pieces
and trying to put all of this together.
- So as you've alluded to,
this field and the related technology,
it's really very quicklygrowing and changing.
So I would assume thatwould mean the goals
of a place like the Institute
for Quantum Computingwould also have to evolve.
Can you tell us a little bit
about how those goals have changed

(07:52):
throughout the timethat you've been there?
- Yes, I'm kind of thinking of this
and kind of putting myself back 20 years
when I first came to Waterloo.
At the time, the goal wasmostly to convince people around
that this idea of quantumcomputing was not totally crazy,
and I say not totally crazybecause we don't have them yet.
And me as a scientist,

(08:14):
as a scientist, you shouldn'tkind of believe something
until you see all the goods.
We don't have a full-fledgedquantum computer today,
and until we have one, youshould have a little skepticism.
Although I reallybelieve we will have one,
but this is a belief andnot the scientific data,
and quite a distinction between the two.
In the 2000s, a lot of the work

(08:34):
of the director of theinstitute was to convince people
that this was really an important field.
And we seem to have done a very good job
because people now are,
there's investment fromgovernment, industry,
many universities across Canada
and around the world havegroup of quantum information.
Now this is different.

(08:55):
Now a lot of the work is reallyto develop these ideas to
in part better understand where the power
of quantum computing comes in,
find new class of algorithms
that kind of quantum computing could help
and kind of make more efficient
and then turn into how dowe rebuild these devices

(09:16):
and building them.
So maybe 20 years ago,we were really asking
how can we really build these things?
Now we have a bunch of blueprints,
and people are in lab tryingto show them, and industry.
Building quantum computershas become complex enough
that it is hard to makethis in a university,
in part because it takes a long time

(09:37):
to go from the first steps tothe device that we have today.
A generation of grad studentsare three, four, five years,
and that's all too short tokind of keep things going.
So we can make proof of principle
of certain mechanism or certain things,
but it is really theIBM, Googles, and Xanadu

(09:58):
and those that are really kind of putting
all the engineering together
and kind of developingthese ideas to get devices.
And indeed, they are producing devices,
not the one what we finally want,
but enough to give us confidence
that we are on the right track.
- Takes a lot of pieces and alot of collaboration, I guess.
- Yes, a lot of pieces,a lot of collaboration,

(10:19):
a lot of stamina,
lot also of understandingwhere the problems
and the challenges are and get over them
and kind of moving forward.
- You said that your primary job
as director of the institute
for the first 10, 15 yearsor so was convincing people
that this wasn't a crazy idea.

(10:39):
Was there a time when youneeded to be convinced
that it wasn't a crazy idea?
Were you a skeptic about quantum computing
before you were a preacher about it?
- Yes, my first piece ofwork on quantum computing was
to try to prove that theywould never work, and I failed.
- You failed and succeeded,I'd say, in an equal measure.

(11:00):
- So after my PhD, I went to Vancouver,
and I worked with aphysicist called Bill Unruh.
And Bill is an incredibly good physicist,
and he has this tendency of,he really likes to argue.
And as a post-doctoral fellow,
it turns out thatsometimes it was very hard
to work with him becauseevery time I had a new idea,

(11:22):
I would tell him black,
and as a person who really likes to argue
and sharpen your ideas,he would say white.
We'd would argue for black and then black,
and then he would kind ofpoke holes at my arguments,
which, after a while,it gets really tiring,
every time you have a new ideathat you kind of get poked.
It is really goodscientifically to do this,
but as a human being trying to do research

(11:43):
and trying to make your namewith kind of being poked.
But I learned that it was important.
Probably 10 years after,
I started to work on quantum computing.
I went, in fact, to aconference in San Fe.
My mentor at Los AlamosNational Lab, Wojciech Zurek,
told me there was this conference
on the physics of information.
And I initially said, "Idon't want to go there
because I don't know anything
about the physics of information."

(12:05):
And Wojciech told me there'sreally neat people going there.
Like, what is it?
It'll take two days.
And it is kind of 45 minutesaway from Los Alamos.
Says, "Just go," and soI said, "Okay, I'll go."
And it turns out that wasthe first time I heard
about this algorithm calledthe Shor's algorithm,
which is crucial for quantum computing.
It's related to factoring numbers

(12:26):
which are product of primesusing a quantum computer,
which turns out to be analgorithm on which cryptography,
in fact, most of today'sworld cryptography is based
on the difficulty of factoring numbers
which are products of primes.
- Cryptography being the stuff
that keeps our information safe?
- Absolutely. When you use your cell

(12:47):
or your computer to log into your bank,
the cryptography that is set up
so that it is private is based,
like breaking thecryptography is equivalent
of finding the factors of a number
which is the product of prime.
So I went there, and sothis computer scientist,
Umesh Vazirani, explained this algorithm,

(13:08):
and in fact, he startedwith a very funny story.
Umesh is a really smart guy.
He always has great ideas, all this.
And he started this talk by saying,
"I haven't done anythinginteresting in the last two years."
What?
And usually scientists are very,all of them are not humble.
- That was put politely.

(13:28):
- So that was a little surprising to hear.
And he said, "But I'veheard about this algorithm,"
which was going to becalled Shor's algorithm.
And he says, "From thisguy called Peter Shor
to factor numbers whichare product of prime."
And there was a buzz in the conference
that this was really important,
and people were talking about it.
At the time, I didn't know,
I knew very little about cryptography.

(13:48):
So it was very hard for meto really assess everything.
But there was really acoherence in that conference.
For those who know physics,
it was like Bose condensationof human beings' thoughts
of kind of suddenly, wow,something's happening here.
I came back to the lab,and I started the thing.

(14:10):
I was working on something
which was called quantum decoherence.
And I said, "Oh, this quantum decoherence
is gonna be an obstacleto quantum computers."
And I started to use littlekind of simple models
to show that if there wouldbe quantum decoherence,
quantum computers would not work.
And so I kind of put things together.
Not everything was tight and clean,

(14:32):
but I was pushing the ideathat quantum computers
would never work.
And one day, there is thisthing called the archive
where we get pre-prints foreverybody around the world.
I look at the archive, andthere's a paper by Bill Unruh
on quantum decoherenceand quantum computers
giving exactly my method.
So I was pretty miffed.(all laugh)

(14:54):
And then I said, "Oh, it'spretty much the idea that I had."
So, okay, my last coupleof months of work,
it kind of goes in the garbage.
But then I said, "Oh, Billalways asked me to argue white
when somebody says black,and the other way around."
So I started to workto demolish his paper,

(15:16):
and I tried to poke holes at it.
- Which was essentially poking holes
in your own ideas as well, right?
- Absolutely.
- Well, as a scientist,- Idea?
- You have to look at both sides.
You don't know where the truth is.
We have ideas, and you neverknow if these ideas are right
or wrong until you gothrough the whole details
of the mathematicalmodels and all of this.

(15:38):
So I was poking the other way around
to try to kind of demolish his idea.
Then I didn't have to say to other people
that I had the same idea.
I can say, oh, this guy was wrong.
So by doing this, I stumbledinto quantum error correction,
which shows that not all errors

(15:59):
will be kind of deadlyfor quantum computers.
There's family of models oferrors that if they happen,
there's ways to take care of them.
At that time, many physicists thought
that this was impossible.
- Because decoherencecauses too many errors
and makes your computation worthless?
- Yes, and quantummechanics has this property,

(16:21):
it's called unitary.
That is, if you makea computation forward,
if it is quantum mechanical,it should go backward also.
If noise comes in naively,
it seems that you cannotgo backward again.
So they would say it's justnot going to be possible
to do this.
The idea at first level seemed to be okay,
but if you start to thinkabout it very carefully,

(16:42):
it is not really correct.
And this is what quantum errorcorrection is really about,
is to find a way to be able to go forward
and backward in your quantum computation,
even if noise comes in.
- So you essentiallydemonstrated the opposite
of what you thought, thatquantum computing is possible.
- I think we should have to,
I should be a little bit more precise.

(17:04):
It didn't show that quantumcomputation was possible
because we don't have them yet.
So we still don't know.
It shows that noiseand quantum decoherence
are not a fundamental objectionto get quantum computers.
- And we also have to thinkabout error correction
in classical computers, right?
So can you tell us a littlebit about the difference,

(17:25):
really, the fundamentaldifferences between classical
and quantum error correction?
- Now that becomes a little bit more,
could become a little bit more technical.
So I'll try not to be too technical.
The idea is first related tothe type of noise that we have.
In classical computers,
all the information is encodedin bits of information.

(17:45):
Bits in information is thesmallest unit of information
that we have typically encodedin a system with two levels.
And we call them zero or one,
like something which is eitherpointing up or pointing down,
that little kind of magnetic moment,
or a pulse of light whichis there or not there,
or a switch on or off.

(18:05):
So all the information is encoded in this.
And the type of noise thatwe have is called a bit flip.
You have one bit.
Let's say you want to send it to me.
If it is zero, we'd get zero,
but suddenly there'snoise between you and me.
And then it gets flipped toone, and I get the wrong answer.
The idea of classical error correction
is not send your bit one by one,

(18:28):
but to encode them so thatinstead of sending zero or one,
you'll send me zero, zero,zero, or one, one, one,
three bit for the one.
And if one of them flips,
you can still recover the information
just by taking the majority.
If there's two errors, thenit's gonna fail, that process.
But the process here will take care

(18:50):
of the one-bit error that comes in,
which would not have been taken care of
if you sent it single bit.
So now when you try to translatethis for quantum computing,
there were fundamental objectionsthat this would happen.
First, the noise in quantummechanics is not discrete
like a zero, one, but itcould look like continuous.
The second one is that it seems

(19:12):
that when we have taken a bit, zero,
and encoded it in zero, zero,zero, we've copied it twice.
And quantum mechanics tells us
that we cannot copy quantum information.
And the last thing is that when we try
to make this majority voting,
then we have to measure the bits.
Another property of quantum mechanics

(19:32):
that I could have mentioned
at the beginning of this podcast,
when you measure it,
you kill the superpositionof zeros and one.
By doing this, then you killthe quantum information.
So the question was how to get over this
and these three objections.
And the three ways now seems obvious

(19:53):
once you know how it works,
but it wasn't around the 1990s.
And I'm not gonna go intoall details how it happens,
but maybe I'll mention one thing.
So, type of noise,
it turns out that althoughthe noise can be thought
to be continuous,
there's a way also ofthinking it as being discrete.
And the type of quantumnoise can be simplified

(20:16):
to have either bit flips,the classical noise,
or what is called a phase flip.
So when we have superposition,
there's something called a phase,
and this phase get changedfrom plus to minus.
So we certainly have twotypes of discrete noise.
And the combination of the two
makes the type of noise that we have.
So the continuous noise thatwe have can be thought of

(20:37):
as a discrete piece,
and then we can get overthat first objection.
And the last two are alittle bit more complex,
so I'm not gonna mentionexactly how it works,
but there's a way to go through.
So there is a theory ofquantum error correction,
and it turns out thatclassical error correction
is like a subset ofquantum error correction.
It's quantum error correction

(20:58):
when we don't have phase errors.
We have only bit flip errors.
And then in that case,things are lot, lot simpler.
- And these considerationsabout noise and copying,
they are challenges thatyou need to overcome
when you're doingquantum error correction,
but are they also kind of advantages
when we're trying to encrypt data?
- Well, the advantage is

(21:18):
that you can keep these superpositions
that we don't care in the classical world
because your bits are either zero or one.
In quantum mechanics, andmaybe I should have said this
at the beginning of this podcast,
that the bits in quantuminformation are called qubits
or quantum bits, a namecoined by Ben Schumacher.
And these quantum bitscan be in a superposition

(21:40):
of being in zero and one.
There's one way of kind ofhaving a picture of this.
You can take the surface of the sphere
as the kind of quantum statethat one qubit can have.
The classical bits are thenorth and the south pole.
We'll call them zero and one.
But if you are anywhereelse on the sphere,
then you are in zero andone at the same time.

(22:03):
And so these differentkind of states allows you
to do something different.
In fact, the transformationto go from zero
to a superposition of zeros and ones
is something that classicalcomputers cannot do.
And so by having a quantum computer,
suddenly you have different types
of transformation you cando with your information.

(22:24):
And the hope initiallywas to find shortcuts,
that there would be shortcuts
that if you had different transformation,
if you can do some thingsthat your peer cannot do,
maybe you can kind of find ashortcut to go somewhere else.
And indeed, quantum mechanics
and quantum algorithms are exactly this.
They are shortcut to get to the answer.
- When you showed me around the Institute
for Quantum Computing for the first time

(22:45):
and showed me what the labs were,
and then I would give toursto visitors around the labs,
and you would see in one lab,
it would be all darkwith lasers and mirrors.
And you'd see these lasersbouncing off of things.
And you go to the nextlab, and there's a big,
the nuclear magnetic resonance can.
I don't know what youcall it, this super cool,
your quantum computerprototype in one lab.

(23:05):
And then another lab has ion traps.
There's all these different approaches.
Are they sort of different attempts
to find the right wayto do quantum computing,
or are they all sort ofpart of the same effort
at harnessing quantum information?
- They're all differentblueprints for quantum computers,
and it's not clear yetwhich one is the winner

(23:26):
in all of this.
People are making bets ofwhich one will be the best one.
Different companies have different ideas
of which one will end.
What they have in commonis that they all want
to manipulate quantum information,
and they have differentphysical implementation
of how to do this.

(23:47):
In some sense, we can think of,
in classical computerstoday who have all chips
will all look the same.
But if you do classical computing,you could have an abacus.
An abacus is a way ofmanipulating information,
and you can have a slide rule
which tells you how to calculate, also.
There are different ways of doing this.

(24:07):
Now, I'm not gonna comparethe different implementation
to the slide rule andtoday's kind of modern,
which one is a slide rule, whichone is the modern computer.
I'm gonna kind of saynothing about this exactly,
but the differentimplementations are aiming
to be the quantum computer.
And maybe it's possible thatthere could be more than one

(24:28):
that kind of works.
Maybe one will work betterfor certain applications.
Another one works better forsome other type of things.
And so investigating thoseright now are all kind
of worthwhile endeavor to do.
And there's also, I would say,
a spinoff of having thesedifferent implementation,
which relates to notnecessarily quantum computing,

(24:48):
but to quantum sensors.
So quantum sensors are sensors
which use, again, rulesof quantum mechanics
to better sense certain phenomena.
It could be better sensethe electric field.
It could be a better to sensethe gravitational field.
It could be better to fieldsome different properties
that we have around.
And by studying eitheratoms or ions or light,

(25:11):
then, in that case, theycan be more appropriate
to certain places.
An example of this is light.
Fundamental differencebetween using light as a qubit
and an atom as a qubit
is that light goes at the speed of light.
It doesn't stop.
So you cannot take aphoton and keep it here.
While you're doing somethingelse on your qubit,

(25:31):
they are gonna move around.
And so you have to find a way
that if you want this photonto interact with that one,
that even if this one goes around,
that it has come back in the right state
to kind of interact.
With ion, it's easierbecause they are in a trap,
and they are there next to each other.
Now, the difference is if you want
to send informationwhich is in an ion trap,

(25:52):
quantum information to yourpartner who's somewhere else,
then you have to use lightto be able to do this.
So you can transferinformation from the other.
from one implementation to another one.
- I remember you describing that
in the early days ofquantum computing's being
somewhat like the earlydays of classical computing,

(26:15):
you had to try different techniques.
And there were vacuumtubes, and that was a step,
and that we don't use vacuum tubes now.
Do you imagine thefuture quantum computers
will perhaps use elementsof what we've seen before,
but perhaps things we haven'teven investigated yet?
- Yes, certainly we might stumble
into a better physical implementation
of quantum information whichis more robust to noise.

(26:37):
In fact, I would say the biggest challenge
that we see today tryingto build quantum computers
is the noise and quantum decoherence.
That's why quantum errorcorrection is really important.
That's the main techniquethat we have right now
to have the idea of scaling up.
But I can see this changing.
There's this beautiful quote

(26:57):
from "Popular Mechanics,"1949, saying the ENIAC,
which was one of thefirst classical computer,
the ENIAC had 15,000 vacuumtube and weighed 30 tons.
And we could imagine thefuture having computers
which would weigh only a ton
and have 1,000 vacuum tubes.(all laugh)
- Dare to dream.
- Yeah, that's it.

(27:18):
And if this would'vebeen a scientific paper,
you would say, okay,they tried to be careful,
but that was "Popular Mechanics."
You would give them alicense to kind of dream
and kind of having a wide imagination.
So it does show that suddenly
when transistors were just appearing
in labs, totally disconnected,
and people didn't think they would be used
for computers at the time, appeared.

(27:39):
And this changed things completely.
Maybe the implementationthat we have today
of quantum computers are the ENIAC type.
Suddenly we could find some form
of artificial particlein material science.
And there are suggestion about this
called topological quantumcomputers with anions.
Maybe these things, if wecan make them in the lab,

(28:03):
and they're able to control them,
they would becomenaturally robust to noise
and give us a chance to scale up.
This is part of the dream,
and we hope that we see these things.
In fact, it would be veryneat to discover something
that kind of suddenlymakes it a lot easier
because today building quantumcommuters is very hard,
very, very hard.

(28:24):
- On the topic of dreaming in the future,
I think this would be a good place
to play for you a questionthat was sent in by a student.
So this one is from Mohamed Hibat-Allah,
and he's a PhD student atthe University of Waterloo
and the Vector Institute in Toronto.
- Thank you for taking my question.
So I'm a physics student atthe University of Waterloo.

(28:45):
My question is relatedto quantum computing.
So as we all know,
there is a lot of researchall over the world
for the purpose of buildinga useful quantum computer.
So my question is,
what do we need tobuild a quantum computer
that is useful to real-world applications?
And what do we need to do

(29:06):
to reach the point where quantum computers
can outperform classical computers?
Thank you.
- That's a very good question
and in bunch of different parts,
so maybe I'll start by the last part
to, like, what do we needto have a quantum computer
which is more powerfulthan classical computers
that we have around.
And it turns out we're pretty much there.

(29:29):
We have quantum computerprototypes around the world,
one at Google, one at IBM,
that are big enough to do a computation
which classical computers
have incredible difficulty to solve.
So we are just on the border.
And a little bit discussionof if we're there,
but to me it doesn't really matter.
And so the challenge thereis that these problems

(29:52):
that these quantum computers are solving
are not that interestingfor day-to-day application,
but I think it's quite a milestone.
If I compare this to 10years or 20 years ago,
then to arrive there,
15 years ago, there werepeople who were saying
that we will never be ableto build a quantum computer.
And here we have a prototype today.
We have controlled thesequantum bits well enough

(30:15):
to do a computation
that the classical computer can barely do.
To turn this into a devicewhich is very useful
for practical application,
then we have to scale thenumber of these quantum bits.
And as we scale thenumber of quantum bits,
it's very hard to makethem more and more precise.
If you have an error ratepair operation, which is P,

(30:38):
then as you have N of these qubits,
if the error pair qubitis P, if you have them,
then the error rate goes like N times P.
So if you have 100 qubits,it's 100 times higher,
and if you have 10,000qubits, it's 10,000 higher.
This tells us that wewon't be able to compute
in a way which is fault-tolerant

(30:58):
or to have confidence in the result
if we don't have a mechanismto take care of these errors.
And again, that's what quantumerror correction tells us,
that we can bring thisNP to some constant value
and compute.
We need to be able to have a device
with quantum error correction.
At least the focus is there.
We don't know how to do this
without quantum error correction.

(31:19):
And so we need to do this.
And that will probablytake another 10 years.
Hopefully I'm wrong,and it's in three years,
or I hope that I'm not wrongthat they'll be in 50 years.
But the consensus and somepeople in industry claim
that probably by the end ofthis decade, roughly 10 years,

(31:40):
we should have these devices.
And we'll need many thousandsof qubits to do this.
So the noise has to be thought carefully
and how do we control these qubits also.
Right now, we do this brute force.
We send one little wire
for every of the qubits that we have,
but if we have a million,
how do we kind of link all of this

(32:01):
and make all these wires thatgoes into all of the qubits?
It's not totally clear right now.
There's different architectures.
I saw something fromIBM Open Day last week
about making a sandwich of qubits
and having wires to come tothem in kind of different ways,
which I thought fascinating.
And although I've seenkind of people talking

(32:22):
about (indistinct) architecture,
they had very concrete plans to do this.
So there will be progress
that will happen the years to come.
So that's why the fieldis incredibly exciting.
There's new thingsevery day in this field.
- This field wasn't the original field
that you got into when youstarted studying science.
You were more interested in the universe
in its largest scales, right?
You were more into cosmology?

(32:42):
- Yes, I was in cosmology,
but a small branch of cosmologycalled quantum cosmology.
What is quantum cosmology?
So the universe is very, very big,
and I've told you a few minutes ago
that quantum mechanics iswhat described the world
when it is very, very small.
So these things seemto be, at first sight,
contradictory in terms,

(33:03):
but the university is verylarge, but it is expanding.
Instead of thinking about the future,
if you look at the past,
means that the universe wasa little smaller yesterday,
even smaller the daybefore, even smaller before.
And then we can trace backusing Einstein's theory
of relativity.
We can trace back and ask the question,
how long does it take
before the universe iskind of small to a point?

(33:25):
And it's roughly about 13 billion years.
And at that point, quantumeffects should come out.
What I was studying is howdo we use quantum mechanics
to describe the beginning of the universe?
So I worked in Cambridge withProfessor Stephen Hawking
on a proposal that he hadcalled the Hartle-Hawking
or the no-boundary proposal.

(33:45):
So he was trying tounderstand how this proposal
was kind of fitting whatwe observe in the universe
and does it make sense
and try to interpret this wave function.
A wave function is a mathematical tool
which describe everything we can learn
from the quantum system that it represent.
I was trying to understandhow it interpret.

(34:06):
In usual quantum mechanics,quantum mechanics in the lab,
we interpret the wave function
as it gives us the probabilityfor something to happen.
And we show that we havethe right wave function
by repeating the experimentsmany, many times.
And then you get theprobability distribution
of different events.
And this probability kind ofmaps with the wave function.

(34:27):
The problem with this, the universe,
we cannot kind of havingmany of these experiments.
We have only one of them.
So how do we use this wavefunction to make prediction?
And it turns out thatdecoherence is a tool,
or quantum decoherence is a tool
to turn this wave function
into probability of classical events.

(34:48):
I knew this quite well,
and this is part that I learnedwhile I went to Vancouver
with Bill Unruh.
And it turns out thatwhen I was at Los Alamos,
my mentor, Wojciech Zurek,
was probably kind of the best known person
in the world workingin quantum decoherence.
And when I went to this talkabout quantum computers,
then I could put the two things together.

(35:10):
Quantum decoherence was an asset
to interpret the wavefunction of the universe
but an impediment tobuild quantum computers.
But again, it's the same mathematics.
I jumped one to the other,
and at that time I thought,oh, I'll work a little bit
on quantum computers for a few weeks.
And then I'll come backto the fundamental issues
of quantum cosmology andwork with the universe.

(35:30):
But I got stuck on quantumcomputers for a little while.
- And actually, one ofyour current students
sent us a question aboutthis time in your career.
So maybe we can play that one.
- Hi, Raymond. This is Matt Duschenes,
one of your students at IQC and Perimeter.
Ray, how did your advisor,Stephen Hawking, react

(35:51):
to your career pivot?
Did you two still discuss science
and quantum gravity topicsafter you transitioned
to quantum computing?
- Again, a very good question.
So I had the chance,after finishing my PhD,
I would bump into Stephen
or kind of go to Cambridgefrom time to time.
And Stephen has alwaysbeen driven by curiosity.
This is something which haskind of always puzzled me.

(36:12):
When I was a student, he wasalready incredibly disabled.
So he couldn't do prettymuch anything by himself.
When I started as a gradstudent, he could speak then,
and he could move a joystick
on his wheelchair to move around,
but he would not be able to put his leg,
or he was barely able to put his leg back

(36:34):
on the little stalls ofhis wheelchair by himself.
But he couldn't feed himself,
couldn't go to the bathroom by himself.
And he couldn't kind of lifthimself in his wheelchair,
so, incredibly disabled.
But Stephen was curious,
and he knew an incredibleamount of things.
I always wonder, howdid he learn all of this
if he had to read a book.
Today, we read on the internet.

(36:55):
We just kind of move frompages to pages or read a book.
He couldn't turn the pageby himself, of a book.
So he had to have somebodyall the time doing this.
Despite all of this, hehad an incredible knowledge
on a broad level and curiousabout so many things.
So certainly when he came to Waterloo,
and Stephen did cometo Waterloo many times

(37:16):
in the last 10 yearsbefore he passed away,
he was always curious tolearn different things.
And I remember at some point I asked him,
"Are you interested tocome and visit the labs?"
He's a theoretical physicist,
so I was not totally sureif that would interest him.
And he was really keen.
He said, "Oh yes, absolutely."
And then I learned that while he was here,

(37:37):
he had gone to SNOLAB in Sudbury.
This is a lab where peoplehave measured the mass
of the neutrino.
Professor McDonald got a Nobel Prize
for the work that they have done this.
And then it turns out that the lab
to measure this in a mine,
and the mine is still active,but you can go and visit it.

(37:57):
You go in this kind of elevator.
You go down, I think it'stwo miles down the ground,
and then becomes really hot.
You go down there with the miners.
And as you get out of the elevator,
the miners goes to the right,
and scientist goes to the left.
And then you walk for abouthalf a kilometer down there.
And then you arrive to aplace which is a clean room.
So incredibly, incredibly clean part.

(38:19):
So it's all closed off, sealed off.
You have to get a showerbefore going to the other side.
The men and women geton two different parts.
They're all stripped off,go through the showers,
go and get dressed, andthen go and observe things.
By the way, if you havenever seen this lab,
and you have a chance in Sudbury, just go.
It's totally amazing place.

(38:41):
But I hear that Stephen was interested,
that he went. (laughs)
And I say, "How was it?"
And he said, "The elevator was great.
It was like free fall."
So for somebody who wasthe master of gravity
to be in elevator for thatlong and felt like free fall,
he thought it was absolutely fantastic.

(39:01):
So he went to visit there, came back here,
and during the week, hecame and visited the lab.
And at every lab, he had somereally interesting questions.
And you know that he knew some pieces
of all the different partsthat we were talking about,
which totally, I mean it,
I said, "Where does heget all that knowledge?"
But it was very interesting.
- I remember when he visitedIQC a number of years ago,

(39:21):
we had a gift made forhim that you gave to him,
and it was a wooden boomerang.
Can you explain why we chose a boomerang
as a gift to Stephen Hawking?
- The first project whenI was a graduate student
of Stephen, which was to tryto prove that the wave function
that bear his name, theHartle-Hawking wave function,
showed that the arrowof time would reverse

(39:45):
at the time of maximum expansion.
So the universe got started very small.
We have the big bang,which is like an explosion.
At that time, the people thought
that the universe would reacha time of maximum expansion
and re-collapse.
At the beginning of the universe
and at the end of these universes,
there are something called singularities,
places where physicalquantities would go to infinity,

(40:08):
which essentially tells you
that the theory by itself breaks down,
the place where somethingdifferent will happen.
Classical relativity,Einstein's theory of gravity,
would break down there
and should be replaced by something else.
And Stephen had been working
that quantum gravity wouldbe what would replace
and smooth out thesesingularities in some ways

(40:28):
because he want his wavefunction that he had picked up,
his quantum wave function,
was smoothing out thesingularity at the beginning.
He thought that it wouldsmooth it out also at the end.
But today we see entropy ordisorder to increase as we go.
So at some point, thiswould have to reverse
and come back so that itgoes to a smooth thing.

(40:50):
That was my first project.
I had to show this.
So he had the idea.
And then he had to show thatthe math agrees with the idea.
So we've talked aboutthis a little bit before.
It's great to have ideas.
Some are right. Some are wrong.
And usually really smart people,
clever people like Stephen,
get them all right straight away.
And I started to work on the math of it,

(41:11):
and I couldn't make it work.
And I would go and see Stephen once a week
and show him my progress.
And he would always pickapart some of my argument
or my comments, or ask me,
"Have you checked this carefully?"
Well, I was a grad student just starting,
so I had not checked everything.
And I'm sure other grad studentswould understand very well
that kind of, you goand see your supervisor.

(41:33):
You think you have everything neatly done,
but something, oh, there are little pieces
under the carpet there thatkind of you had assumed.
And that's why Stephen wouldpick at me all the time.
Fortunately, after a couple of months,
one of his ex-post docs, Don Page, came,
and he asked me what I was working on.
And I told him, and I said,"I just cannot make it work."

(41:56):
And he said to me, "Oh, it's interesting
because I've been thinking about this.
And also I believe thatit's not gonna work."
So then I felt reassured
because for the last kind of six months,
I thought that I wasthe one who was wrong.
And so Don, who was abit older than me, said,

(42:16):
"Stephen will never agreeif we just go brute force
and tell him he is wrong.
What we have to do is slowlyputting the pieces together
and build our arguments and addone more piece to the other,
which each of these little piece don't say
that the arrow of time will not reverse,
but kind of all togetherwill kind of bring."

(42:37):
And so we did this, and afterabout two months of arguing,
that both of us kind of wereputting, Stephen came and said,
"It's never gonna work."(all laugh)
And then, so you say, "Ah, yeah."
When I finished my PhD, Stephengave me a copy of his book,
"A Brief History of Time" and, well,

(42:57):
a quotation at the beginning:
"To Raymond, who showed me
that the arrow of timewas not a boomerang.
Best, Stephen Hawking."
So when he came to visit here,
it was kind of 20 years later.
Then I gave him a boomerang of this.
And then he had a big smile on his face.
And interestingly enough,in the following year,
there was a documentary on him

(43:19):
that I was watching at somepoint, and it was at his house.
And I could see in the background,
the boomerang was thereon the wall, put there.
So this is the story of the boomerang.
- Well, this actually leads
into one more question that we got,
and this one was fromNayeli Rodriguez Briones.
She's a postdoc at the Universityof California, Berkeley,

(43:40):
but she did her PhDdoing some work with you.
And so she actually wanted to know
what your fondest memoryis with Stephen Hawking,
and you've shared a few now,
but I'm curious, what's thefondest when you look back
on all those times?
- Maybe one piece thatsurprised me about Stephen
is scientists, some ofthem are very stubborn.

(44:03):
Some of them kind of have ideas,
and they think that alltheir ideas are right.
One thing which really amazed me
with Stephen is when suddenly he realized
that he had made amistake on this proposal
on the arrow of time,he totally turned around
and said explicitly in conference
and talked in his bookthat he had made a mistake

(44:25):
and realized that thingswere going differently.
And he gave me a lot of credit for it.
I thought it was incredibly generous.
And so that was a part of Stephen
that I didn't know that much before,
that he was my boss andincredibly smart person.
I was a small graduatestudent kind of stumbling

(44:46):
on this problem.
- I can't imagine the intimidation factor
of telling Stephen Hawking,
"I think you're wrong about that."
- Yeah, I must admit
that I never said it explicitly that way.
I would go to the Blackboard and say,
"I don't see how this can work,"
or "I don't see this working."
And then you would go,
I would tell him I've done this and this

(45:08):
and do this calculation.
And if I look at this, I get this result.
And so I'm not gettingwhat you're thinking.
So a little bit different than saying,
"You're totally wrong, Stephen."
Another thing of Stephen which is amazing
is his sense of humor.
He liked to tease people,
and this happened often between him and me

(45:29):
and the staff around kind of
where we'd play tricks on each other
and throw things to eachother at different place.
He would have a good laugh,and I was not very shy.
And this, I don't know why is that,
but many people who arrivednext to Stephen totally freeze,
and he was very, very disabled.

(45:51):
And his voice was distorted
when you started to talk with him.
When I started my PhD afterthat, he had a computer.
So people would kind of,
often if I would be helping Stephen,
they would ask questionto me instead of Stephen
because they don't knowwhat kind of reaction.
Maybe I can thank my mother,who was very hands on

(46:14):
and not be shy and alwaystelling us, the kids,
to help whenever help was needed.
So I would help Stephen,
and sometimes I would say to Stephen,
"I just don't know what to do now,"
kind of trying to help him whenthings were not going right.
Stephen's sense of humorcomes out in different ways
that quite often people don't notice.
And once you notice it, he likes to joke.

(46:35):
He likes to tease people.
He likes to kind of have fun.
That's one part that Ireally was impressed of him,
of somebody who's incredibly disabled.
I've rarely seen people as disabled
in my life who can still function
and do extraordinary things
of being a worldwide scientist, traveler,

(46:59):
nearly a rock star in many ways
but at the same time beingincredibly, incredibly disabled.
This is something that really impacted me,
saying, if you reallywant to do something,
then things are possible.
Like don't let yourselfkind of pity yourself
and stumble on throughthings because of hurdles.

(47:22):
- That actually leadsinto my next question.
One of the reasons we're sodelighted to have you here today
is that a doctor told you some years ago
there was no guarantee thatyou would be anywhere today.
So you had a prognosis of cancerthat came out of the blue.
Can you tell us whatthat was like for you?
- Yes, 5 1/2 years ago,
I was diagnosed with lungcancer, stage three also.

(47:45):
People who know aboutthis know that prognostics
were not that great at the time.
So I was told that I had about 20% chance
of surviving five years.
Except for the lungcancer, perfectly healthy.
I like to do outdoor stuff.
I like to go on bicycle.
In fact, while I was being diagnosed,
I went on my bike to a little cottage

(48:07):
that we have on the way toOwen Sound very far from me,
not very far from here,about 125 kilometers.
I could do this,
so didn't feel really thatthat impacted me that much.
But the doctors told methe chances are very slim
to go through.
And that only made me change a little bit
my view of the future.

(48:29):
It turns out that I had been director
of the Institute for Quantum Computing
for pretty much 15 years.
I had told the institutethat I was not going to ask
for another mandate.
So I could just kind of quickly wrap up.
And I thanked my colleagueand partner Kevin Resch,
who have taken over at theinstitute at that time.

(48:50):
And then I had to go tochemo, surgery, radiation,
and all that stuff, and more chemo.
So many things seems tohave kind of picked up,
and things went okay.
I had a recurrence about three years ago,
but it turns out that theparticular cancer that I have is,

(49:11):
one particular pieceof my DNA has changed,
and there's targeted therapies.
It's a mutation of theDNA, which is known,
and there's a drug that kind of came
to the market five or six years ago.
And that particular drug kindof stops the cancer to go in,
and it's been incredibly good.
So, thank you for medical researchers,

(49:33):
people who design drugs.
And thank you for thecompany who makes this drug
that I'm still alive today.
And here I am, and things look good.
- You mentioned last time we spoke
that there's actually a note on your file
at the regional cancer center saying,
"Note, this guy's a physicist,
and he'll ask a lot of questions."

(49:55):
Can you tell, were you asking questions
about the machinery they wereusing for their diagnostics?
- Yeah, in fact, when I had treatment,
there was a kind of three piece of it.
Surgery, that's kind of biology stuff.
And with this,
I don't feel that muchattraction to that kind of stuff.
Then there's chemotherapy, chemistry,

(50:17):
all these stinking stuffand kind of liquid things
that again, I'm not too keen on this.
I tried to understand alittle bit how it works,
but it's not natural to me.
Radiotherapy, that's radiation,
That's electromagnetism.
Ah, this, I can read about this.
I can try to understandkind of how it works.
So I started my treatmentof radiotherapy here

(50:38):
at the hospital in Waterloo.
And I started to askquestions about the machine,
and I was really curious tosee kind of how it works.
So I started to say,
"Well, what is thefrequency of the radiation
that we have?" and the staffwho were going kind of,
"Oh, I'm not really sure.
We'll kind of ask."
And they would come back and tell me this.

(50:58):
So some of the question I would ask,
they would come back and know the answer,
kind of how long does thatthing process work and all this,
how do you calibrate the machines?
One day I came in, I said,
"Well, do you have the instructionmanual for the machine?
I'd like to double check a few things."
(all laugh)
So they burst laughing.

(51:19):
And he said, "We have a medical physicist
on staff at the hospital.
Maybe we can set up anappointment with him."
So his name is Ernest Jose.
And so the next time Icame after my appointment,
he was there waiting, and he said,
"Apparently you're a curious man."
And then he told me this.

(51:40):
He said, "Apparently in yourfile, there's a note saying,
'This guy is a physicist andasks a lot of questions.'"
- Amazing.
Did they ever give youthat operations manual
for the machine?
- I didn't get it through the hospital.
I got it through the internet somewhere.
I kind of figured it out.
And then interestingly,
the medical physicist wasgiving course on oncology

(52:03):
and therapies at the university,which I didn't know about.
I asked him if I could get in this course,
just be a listener, to which he laughed,
and he says, "If youwant to, that's fine."
So I joined the course,
and I spent the rest of theterm kind of at the back
of the lecture room and askingquestion from time to time,

(52:26):
trying not to intimidate thestudents who are at the front.
But quite often, they had questions
about what do patients feelwhen certain things happen
and kind of questionsthat patients would have.
And so there, I couldhelp them a little bit.
So now I know about radiation theory,
and I'm thinking that maybe there are ways
that quantum technologies
could help them kind of controlling,

(52:48):
after all of this,
kind of comes down tocontrolling radiation.
In the NMR quantum computing that I do,
we do control theradiation in certain ways
to reach certain goals.
So I think some of thesetechniques can be applied there.
- So you've sort of become interested
in new fields a few times, right?
You started out workingin quantum cosmology,

(53:08):
and then you became interestedin quantum computing.
And now you've acquired some knowledge
about medical physics.
But I think it must be very difficult
when you try to start learningabout a whole new field.
There's so much vocabulary
and maybe assumptions thatpeople take for granted.
Was it difficult to move
into those new fields a couple of time?
- Yes, there's definitely some hurdles,

(53:29):
but I would say thisis the price I'm paying
for being curious.
It's a wonderful thing to be curious
because it tells youthat you're never bored.
There's always some neatthings that you can learn about
or kind of, I like tounderstand how things work,
let it be quantum computing, qubits,
or quantum cosmology.

(53:50):
Or I have a Volkswagen van 1979,
and it doesn't always work perfectly
so that there are piece Ineed to understand there.
And while you do this,
indeed, there's lingothat people are using.
And that's probably most of the challenge,
is to understand exactly whatis the lingo that people do.

(54:11):
And all different fields havedifferent kind of assumption
that people absorb withoutsaying very explicitly.
And these are the hardparts to kind of get over.
But once you know thatthese are two hurdles,
then you can pick thebrains of other people.
So knowing this and not beshy about asking questions

(54:34):
is something which is critical.
I try to get my students not be shy.
Personally, I'm a person who's shy
in kind of lecture room and all of this.
But now that I know enough things,
then that gives me lessshyness to be able to do this.
And if my question is a little too naive,
then I'll say, "Okay, I'mjust new in that field.

(54:56):
So what?"
And maybe being a little bit older,
I've become less shy of being seen.
So quite often, I see students worry
about looking like foolof asking naive question.
But what I have learned
is that sometimes the naivequestions are the hardest one
to answer like the basicassumptions in fields

(55:16):
of why do we do this this way?
It's kind of much harder to answer
than a really specific technical tricks
that people are using toget a solution of something.
So asking things about the assumption is,
I think, very important
because once you know the assumption,
and then you learn abit of the mathematics,
then it's straightforwardto kind of move on.

(55:38):
- You've mentioned in thisconversation several times
the power of curiosity.
I remember you gave a TEDxtalk about 10 years ago,
and the very first wordof it was curiosity.
That was a standalone sentence, curiosity.
Is that something
that's you've hadinnately your whole life?
Have you always been that way,
or is that somethingyou've developed over time?

(55:59):
- That's a really good question.
I think there's an innatepart that everybody has.
I think it comes downto Darwin's principle.
Humans who are really curiouscan harness this curiosity
to turn their life into something better.
And I think that's the storyof developing technologies.
So you start with curiosity,

(56:21):
and suddenly people like me will face this
kind of trying to understandthe world around us
and try to ask questionabout how does it work
and kind of why do we see what we see
and trying to build what we call theories.
Theories at first step
try to put together a bunch
of data of observations
and kind of link them in a consistent way.

(56:43):
But a second step ofthe theory is something
that allows us to make prediction
of what's going to happen in the future.
And then that's one waythat in a scientific matter
that we prove that our theories are good,
is that they have a predictive power,
and they agree with the future experiments
that we're gonna do.
But also once you knowhow to predict things,

(57:06):
you can learn how to controlthese physical phenomena
that we have around.
And once you can controlthese physical phenomena,
you can make them dothings that helps you,
that helps you to survive.
And that's what we call technologies.
And I think the cycleof going from curiosity,
making theories, controlling,

(57:27):
and then kind of developingthese technologies
have come again and again.
And once you develop new technologies,
interestingly, you can pushyour curiosity steps ahead
or further down or further up,
depending on the scalethat you're looking at
in trying to understandmore physical phenomena
and take that cycle goingagain and again and again.

(57:48):
And so I think curiosity issomething that everybody has.
People use them in differentdegree, I would say,
but I think everybody's curious,
and that's what makes us drive
and kind of ask interesting question.
- Ray, I could talk to you all day,
and there have been times whenwe have chatted for hours,
but we won't keep you any longer.

(58:08):
Can you just share withus what your outlook is
for the future and yourresearch and your curiosity?
- Well, I think you want totalk for a few more hours.
(Ray and Colin laugh)
I'm curious about different things.
Now I have the luxuryof not being director
of any institute.
So I have plenty of time to do things

(58:28):
which, when I was director, I had to focus
on developing this Institutefor Quantum Computing,
but now a lot of time to read things.
And I get lost from day to day
on kind of reading too many things,
but definitely on the scientific part,
I want to better understand how
to control these quantum systems.
Also having been adirector of an institute,
I want to understand howdo we really go from ideas

(58:52):
and this curiosity toreally develop technology,
and how do we do this in aCanadian context, for example.
What are the piece that we'redoing very well in Canada,
and what are the piece which are missing?
That's another part.
And if we go to kind oflarger and larger scales,
one day, I'll come backto quantum cosmology
and trying to understandhow the universe works.

(59:13):
And between the small world
and the large scale of the universe,
there's plenty of thingsto push my curiosity
in different direction.
- Wonderful.
Well, thank you so much forspending the time with us today.
- You're welcome. Great pleasure.
(soft electronic music)
- Thanks so much for listening.
Perimeter Institute is a not-for-profit

(59:33):
charitable organization
that shares cutting-edgeideas with the world
thanks to the ongoing support
of the governments of Ontario and Canada
and thanks to donors like you.
Thanks for being part of the equation.