Hello, and welcome to the Physics World weekly
podcast.
Last week, Physics World's Matin Durrani boarded a
ferry in Hamburg
that was bound for Helgoland,
an archipelago
in the North Sea, about 70 kilometers off
the Northwest Coast of Germany.
It was a century ago in Helgoland
that the physicist Werner Heisenberg
devised the mathematical
framework
that underpins our understanding of quantum physics.
Matin was there with some of the world's
leading
quantum physicists
for a conference called Helgoland
twenty twenty five,
one hundred years of quantum mechanics.
And this conference celebrated Heisenberg's
brief stay on the archipelago's
main island.
Matin caught up with three eminent scientists
and asked them to reflect
on Heisenberg's
contributions to quantum science and also
to look forward to the next
one hundred years of quantum
science and technology.
Here are those conversations.
My name is Tracy Northup. I'm a professor
at the University of Innsbruck in Austria.
I'm a professor in experimental physics. My group
works on quantum interfaces,
between,
light and matter.
And we're in Helgoland,
in Germany at this conference celebrating a hundred
years of quantum mechanics.
And is this your first visit to Helgoland?
Have you, felt any
inspiration from Werner Heisenberg from all those years
ago? It is my first visit to Helgoland.
It's a very remote island. It's beautiful, and
it's so certainly inspiring to be here.
And we've heard a lot about fundamental questions
in or the foundational questions in quantum mechanics.
Do those interest you, and what do what
most inspires you about those questions?
I think these foundational questions are absolutely interesting.
It's it's not what I work on myself.
I'm an experimental
researcher where we work with trapped ions and
trapped nanoparticles.
But it's fascinating to hear about these questions
that my colleagues are engaging with and also
to think about what the repercussions of those
questions are for experimental physics. You know, how
does our
interpretation of quantum mechanics, how does that shape
how we think about quantum mechanics, how we
think about our measurements,
how we think about this interplay between experiment
and theory?
So tell me about the panel that you're
chairing on the last day of the conference,
Saturday. Who who who who's going to be
on it, and what will you be discussing?
Right. So on Saturday, at noon, I'll chair
a panel. It will be the the last
event at the conference, and it will be
about the next hundred years of quantum mechanics.
So that's an exciting topic. It's a daunting
topic. And, the panel members are Peter Zoller,
Gerd Leichs, Lorenzo Mccone, and Ramon Schnabel. So,
really leading,
theorists and experimental physicists, in quantum mechanics, and,
I'm looking forward to their insights.
So, I mean, how are you gonna pack
the next hundred years into an is it
an hour? That sounds really, really ambitious. I've
I've good luck to you. How are you
going to do that? Yeah. It is an
hour. So
we'll we'll start by having,
each panelist comment for a few minutes on,
you know, some of their thoughts,
and then we've put together some questions that
we've discussed in advance that we thought would
be interesting to to kind of see some
different counterpoints on.
And so we've, we'll have a couple of
different panel members address each question.
And, yeah, I think we're we won't maybe
tackle the whole hundred years all at once,
but, but I think maybe also kind of
in the shorter term, what are we looking
forward to seeing?
What are some trends that that we see?
So where do you think most progress will
be made in the next hundred years? What
do you think? Where where's your money on?
What what what's what progress will we see
the quickest pace of change?
Oh, you know, I think it's it's so
hard to say. So maybe I will I
will stick with what I know best. You
know, this morning actually here at the conference,
we heard about,
macroscopic quantum mechanics, about people,
like Marcus Arndt and Marcus Asplemaier,
looking at,
we quant sorry. The the weave dynamics of
of of
of of of matter and also asking, you
know, can we build experiments to test the
interplay of gravity and quantum mechanics? And so
I find this frontier
of trying to build
macroscopic
quantum states really compelling. And,
because there's been so much progress, you know,
it's something I, it's it's a field that
we also work on in my group,
and and I'm I'm really excited to see
what comes in the next few years. So
if we were here in a hundred years'
time, there was another conference celebrating two hundred
years of quantum mechanics. What would you think
would be the,
you know, the the big questions on the
horizon in a hundred years? Or what would
be what would be celebrating in a hundred
years? Sorry. That's a really difficult question. I
don't envy you trying to answer it. Yeah.
I think I think the most honest answer
is I just don't know. You know, something
I was thinking about today is
where would where would people have been in
previous centuries? You know, when we think so
in 1925,
it's Heisenberg here making this this breakthrough in
the development of quantum mechanics. When we think
a hundred years before that,
people were just sort of figuring out that
electricity and magnetism were were two aspects of
the same thing. And so, you know, for
those for that those people to have imagined
quantum mechanics, you know, that was so far
beyond
where they were, and and they they didn't
yet have,
Maxwell's equations and electromagnetism.
And then, you know right. So it's interesting
to imagine what
Heisenberg and and Born and Pauli and the
set of people in in the nineteen twenties
would have imagined for now.
I,
I yeah. Is it now perhaps in terms
of these foundational questions, you know, how do
we interpret quantum mechanics? Perhaps that's something where
they might have thought we would be a
lot further along.
But until yeah. I feel the same that
same gap in in saying, you know, I'm
sure that in in a hundred years, we
will be somewhere that none of us can
picture right now. So will we all all
be sitting here with quantum computers on our
laptops and,
you know, sending messages, you know, with QKD
and, you know, what will we be doing?
How what sort of technologies can you imagine
us having ordinary people having?
Right. I mean, I think we're we're still
quite clear that we expect quantum computers to
be used for very specialized tasks.
So it's it's hard for me to imagine
us having quantum computers, you know, sitting on
our laps because I I I I I
can't imagine the need for them. But I
I do picture
that we would have access, you know, via
the cloud, via secure communication channels,
two powerful quantum computers that that maybe we
would be using, you know, researchers here at
that conference would be using to be running
simulations or calculations in in parallel with with
with meeting here. And I think these kind
of channels for secure communication, quantum communication,
will become, right, cheap and accessible. That's something
that we're we're hoping. Because
because some people are quite interested in the
sort of ethical questions about quantum. Is that
something that concerns you, or do you give
much thought to that?
So I think, right, ethical questions of any
new technology are are crucial and important.
But it's also a question of when is
the right time that you start writing those
regulations. You know? And and, for example, if
if if we were trying to regulate
AI,
you know, twenty five years ago,
would that have made sense?
And so I I think people are with
quantum. I would say that with quantum knowledge,
people are quite
aware of or thinking about
questions about ethics and regulation
in,
in a nice way. I mean, I see
those discussions already happening.
But I think the point at which you
start
start regulating that in in a,
that that we're we're not that's it feels
too early for that for me. But you
definitely think we'll be here in a hundred
years. Do you think we will still have
meetings that we will come together and, we'll
be going up to the Heisenberg monuments in
a in a 100 years' time?
But it's also a great question. Yeah. Right?
Will it will it still make sense that
you bring everybody together,
for these kind of meetings? You know, I
I think what you see after the pandemic
is that people kind of value meeting in
person in in a in a special way.
Right? We say, look, there are things that
where it's really worthwhile
not to do this over Zoom,
but also to to take the time, right,
to carve out time in our schedules to
just have these discussions.
And so,
yeah, I I certainly,
imagine that that will still be the case,
that that's something fundamental to to being human.
But we also think about you know, we
have also have to be aware of the,
you know, the ecological cost of travel. Right?
You know, to this, how often does it
make sense for for for us as a
community to come together and to travel over
great distances to do that?
But I think these these meetings are very
special opportunities.
And how did you enjoy the ferry ride
over? You know, that was quite exciting, wasn't
it? It was quite about three and a
half hours from Hamburg. Three and a half
hours from Hamburg. You know, most of it
was on the Elbe, which is quite quiet.
It's, you know, the river. But then when
we got into the open sea, it was
a little choppy.
I was outdoors, so I felt, like, you
know, getting a little wet, but I think
I, didn't get too seasick.
It's funny to think about Heisenberg doing his
calculations because he wouldn't have had anything other
than sort of textbooks and then his pen
and paper, and there would have been no
telephones, no any way of communicating, no radio.
It's really bizarre to think that, you know,
the progress he made with no technology at
his fingertips.
Right. It's a sort of picture that he's
kind of over here where he's brought some,
you know, books and paper, and that mostly
he's kinda wandering around the island, you know,
recovering from his allergies,
getting some exercise,
but then, yeah, kinda sitting down and scribbling
and and working things out in his head.
Yeah. Do do you worry about AI or
anything? Sorry. Going off completely off, of quantum.
But AI, is that something that worries you
about how we all sort of learn and
do physics in the future?
I mean, it's I I think it's certainly
something that we all have to engage with.
Right? What
how can we use it to help our
work? You know? And that's, of course, not
just for physics. That's for everybody in the
world. You know? How how does it how
do we
use it to, you know,
to allow us to do things that maybe
we couldn't do otherwise?
But but also to acknowledge that what are
the things that we are currently doing well
and that where we don't think it can
replace us. Of course, the tricky question is,
you know, the answer in six months or
a year is gonna maybe be different than
what what what we know now.
So, yeah, I think it's,
and and
so it's it's this very positive development, but,
of course, plenty of
ethical questions there and just questions about how
does this change the way we work? How
do we evolve as scientists? So do you
use AI in your work at all? Is
there any way you use it for helping
with your experiments or with your research papers?
Right. So in,
not really currently.
Is I,
I think maybe people in my research group
would be using it perhaps for kind of,
for help with with coding, with programming something,
or
for,
checking, spelling or grammar on a paper, that
they're writing. But but,
I think we we haven't kind of implemented
any kind of
structured use of it in our room.
Alright. Well, let's hope maybe in a hundred
years someone's gonna listen back to this conversation.
Who knows? I wonder what they make what
they make of it. Thank you very much,
Tracy. You're welcome. Thank you so much.
So I'm Michelle Simmons. I'm the CEO and
founder of Silicon Quantum Computing in Sydney, Australia,
and we're currently at the hundredth anniversary of,
quantum physics in Helgoland.
And this is your first visit to Helgoland.
What's been your impressions of, following in Heisenberg's
footsteps?
This it's been pretty amazing
mainly because of the, variety of the talks.
But also, I think,
Heisenberg came here to get away from the
rest of the world and to have clarity
of thought by being in a beautiful location,
and so it certainly is that. And have
you had any clarity of thought yourself?
I have. So I'm known to be a
workaholic,
and so I have very much enjoyed I
get up very early walking across the island
and looking at the wildlife,
looking at the little fairy birds that are
out there, and,
and then basically being in the North Sea
wind, which is strong and refreshing.
So you originally, you did you you're from
The UK, aren't you originally? You studied at
Durham. Is that right? And, in fact, you
were at the Cavendish, I think, when I
was there in the nineties, so maybe we
brushed past each other. But you've been in
Australia for quite a long time now. Yeah.
So, yeah, I grew up in London, went
up to Durham, and then, as you say,
was in Cavendish from '92 to '97.
Oh, sorry. '92 to '99. And then, yeah,
I went to Sydney, and I've been there
for twenty five years now.
Very much focused on one big mission, and
that is to build a quantum computer using
atom qubits in silicon.
And are there many people doing that sort
of project who are here at Helgoland?
So that there's actually a lot of theorists
here mainly. So but there are a few
experimentalists hidden amongst them. And a lot of
those experimentalists are right at the forefront of
their respective field. So either,
in ion trap quantum computing or superconducting qubits.
So it's quite fascinating to be here. There's
been a lot of talk about sort of
foundational work. Is that sort of relevant to
what you're doing in your group?
Yeah. So in quantum physics, obviously, it's a
field that's very rich. It's, you know, 100
years old. It is, mainly academic and theoretical,
has been for a long time.
But I call it the golden age of
the experiment. This in the last twenty five
years or so, we now have the tools
that allow us to manipulate the world at
the very smallest length scales. And so we're
able, really, for the first time, to try
and control quantum states and then see if
we can use them for different types of
information encoding or for sensing.
And then sorry. I can't remember. Are you
presenting a talk at, Helgoland?
So I'm actually on a panel tonight.
And that panel, I think, is gonna hopefully
have a little bit of controversy, but really
talking about, quantum physics in the future. So
if we came back in a hundred years'
time to Helgoland in, 2125,
what do you think where would be with
quantum physics, quantum computing? Can you can you
even look that far ahead?
I I don't think I can. So I'm
a very pragmatic and practical person. So I
think I have always tried to plan my
life ten years ahead of where I am
today.
And so I think the next ten years
are certainly gonna be very exciting for the
field. You can see that there are companies
setting up all across the world,
really making practical systems now.
So we believe we've got some processes in
the quantum machine learning space that are showing
advantage today, and that's something we didn't anticipate
until another four years from now. And so
I think the field is rapidly accelerating, so
it's gonna be hugely exciting over the next
five, ten years. And what sort of skills
do you think, you know, physicists need if
they want to go into the quantum sector?
I mean, you've obviously set up your own
company. There's obviously lots of opportunities.
Huge opportunities in this field at the moment.
I think, obviously,
having a background in physics and maths is
is fantastic for this field, but also statistics
and coding are two areas that are are
fundamental.
But as it becomes very experimental and practical,
then you need skills right across the board
of people that manufacture things, people that make
instruments, that measure things very precisely.
There's a lot of theory that comes quite
embedded in a lot of the experimental work,
so getting very close to the experimentalist as
a theorist would be ideal.
But then, yes, with companies, you have products.
So it's really kind of expanding,
to all the skill sets you would have
for a new industry.
So which sort of products are closest to
market? People talk about sensors being very close
or what but, obviously, maybe you you think
differently.
Yes. So sensing is always believed to be
the closest. But, in the machine learning space,
I I think that's that's real now. So,
we have a processor that gives, an increased
accuracy for feature identification,
and that's something that we're selling today. And
so lots of companies are very keen to
increase the accuracy of their classical machine learning.
Right. And you also won that award. Was
it Australian of the Year a few years
ago? Have there been any other Australians of
the Year on Helgoland, do you think? I've
never thought about that. It's an interesting concept.
I would doubt it, but who knows? Who
knows? So any final thoughts before we finish?
What's your, what's your vision for the future
of Quantela?
Yeah. Look. I I have actually been reflecting
whilst I've been here, and I think one
of the things that I
feel more and more as I get older
is the ability to separate yourself from the
herd and to think independently and get away
from things every now and again is quite
vital. So
having walked around this island, I've got the
sense that that's probably what Heisenberg did when
he came here. So he basically detached from
the rest of the world to have clear
clear thoughts. And so yeah. So as a
physicist, it's very,
it's very compelling to work with others. That's
a great way to expand the knowledge of
yourself. But fundamentally, learning is an individual thing.
And so deep learning and spending time by
yourself really reflecting on what you know and
what are the challenges ahead, I think, is
quite quite important.
Very profound. We'll we'll finish there. Thank you,
Michelle.
Peter Zoller is my name. So I'm a
professor, actually, now emeritus professor
at the University of Innsbruck and also at
the Austrian Academy of Sciences.
We have a quantum institute that's called the
Institute for Quantum Objects and Quantum Information in
Innsbruck in Austria.
And, we're here at, the Helgoland meeting. Is
this your first visit to Helgoland?
It is my first visit to Helgoland, and
I always wanted to have, you know, a
pilgrimage
to Heisenberg's,
place where he invented quantum mechanics. Yeah. It's
the first time here. Did you go and
visit his, the little plaque where he, is
honored? I saw that, took my photograph, and,
you know, that's right. And, of course, you
know, wrote it there. I know it's it's
a sight. You know? Peter was here.
Did you feel any inspiration for it? Was
it a sort of profound moment
going there? I'm still I'm still waiting for
that, but, who knows? Maybe, you know, after
my talk or after my panel,
participation then. So, yeah, you're talking the panel,
which is tomorrow, actually,
the future the next hundred years of quantum
physics, which sounds really ambitious. What what points
are you going to make in the debate?
Okay. So, we sort of discussed inside of
the panel how we distribute and our our
contributions, and I will talk about the future
of quantum information. And,
of course, I mean, the main statements will
be, and I really believe that it's a
little bit black and white that, no, that
I think we are not too far away
from building fault tolerant quantum computers.
This will come. The question is to know
how big we can make them and how
we can scale them up and all that.
This will be technical
developments. This will sort of proceed in different
thresholds and so on, but it will come.
This is for me very clear. And I
think that this will open new doors and
will also, I guess, open new doors. That's
sort of my second statement in this context
that I think that a lot of the
qubits that will have logical qubits, you know,
many of them, at the end of the
day, they will become cheap.
And, also, at the moment, we have all
of this discussion. Quantum information processing is very
expensive, but we have quantum advantage. Can we
demonstrate?
But at the point where qubits, fault tolerant
qubits become cheap, you know, then it's a
complete game changer. And many things that we
are doing today, you know, in the classical
context, in the quantum context, we know it
can be done better. But once it becomes
cheap to do quantum, you know, then this
is sort of another threshold to this context.
Do you have a def definition for cheap?
What do you,
compare that to?
Well, I would say cheap's very similar what
we saw in, for example, classical computing. You
know, I still remember when I bought my
first laptop or or Apple computer, how much
money I put down. You know? I went
to BMW to work for the whole summer,
cleaning in the factory, but not whole summer,
three weeks or whatever it was, and making
some money. And then I bought myself,
just a Hewlett Packard calculator, you know, that
could I could program 128
steps,
later on, you know, buying again from sort
of money that I earned over the summer
as a student and the first computer, first
laptop. And so,
today, these things are cheap and all relative
to the salaries that we have. And so
I would expect that Quanta will also become
cheap at one point and all in a
very similar way. Yeah. What sort of, applications
do you foresee being used over the next
hundred years?
I think that this is sort of the
main bottleneck that we have in this, quantum
computing or quantum information context that, I mean,
Ike Chuang here at the meeting
made a strong statement. He said that, you
know, we are sort of progressing and being
able to do all of these things, but
we have not really very much advanced in
terms of finding applications of quantum computing where
we can claim that this will be of
an
social economic
benefit and so on that, you know, companies
at the end have to make money. And,
of course, there will be these things will
be funded by military, but at the end,
you know, you won't would like to identify
applications. And, I see a lot of, you
know, applications that,
that are sort of, you know, one side.
You know, these quantum computers that we will
produce a new quantum technology.
I'm very excited about bringing them back into
physics. You know? They will be the basis,
like, in the context of quantum sensing, and
I could list here many examples in this
context, you know, that will allow us to
discover new physics.
So I see new technologies as a door
to find to making fundamental discoveries on the
physics side.
Kind of saying the obvious, but I think
it will be true here. And, you know,
these things about gravity that we're hearing here,
you know, like,
you we have quantum communication. You know? There
will be quantum sensing networks based on have
you learned how to do quantum communication and
getting entanglement over large distances?
There will be quantum sensors, you know, in
a new way. This will be a new
interface to, for example, gravity. Talk about, you
know, classical GR
and provide new,
measurements, you know, new instruments for measurements. And
at the end, I think something very interesting
will come out because
even more, at least, atomic physics had a
very long tradition and, you know, high precision
measurements. Think about the lamp shift. You know?
It was technology of microwave in the in
the second World War then applied to spectroscopy.
We discovered the lamp shift. So it will
be very similar over here, at least I
expect. So that it will be this is
a door opener for fundamental discovery. It also
meant there's many applications in science.
On the other hand, you know, industry, as
I said, you know, wants to make money,
on one hand, building a quantum computer, on
the other hand, also then, you know,
solving useful problems for society.
And, you know, one obvious statement has always
been that, you would like to do, for
example, quantum simulation for drug discovery or chemistry
and all of these things, quantum material design.
So tomorrow, we'll make a a brief statement
about things that we're working on at the
moment where we are doing what we call
inverse quantum simulation, where we write down we're
sort of doing quantum material design on a
quantum computer by writing down the list of
properties. You know? We encode them in a
cost function that we solve in a quantum
computer, and what comes out at the end
is the Hamiltonian that generates this thing as
the ground set or is an approximate
ground set. And so this becomes in a
way of doing
material design. And, this looks actually very promising
and it's a very constructive way
of, you know, designing
this particular case materials or the molecules or
whatever, you know, that have desired properties. And
I think it's a beautiful application, and,
we have to search for ideas along, these
slides. So So it's interesting you say new
advances in technology can feedback and create new
fundamental discoveries.
Have you got some examples about where that's
happened in recent years? Well, in recent year,
examples that happened in the past in the
recent years, well, I would say that,
maybe not at the level of now quantum
computing coming back because quantum computing is a
whole new paradigm. But, you know, if you
look at the development of the laser, you
know, that the at the very beginning was
just, you know, a coherent light source, and
we learned how to stabilize these things. And
when you listen here to the talk by,
for example, Junier
on,
on atomic clocks, you know, that measures now
time accurate to 21 digits.
I mean, this is just amazing. And this
was sort of one example where sort of
there was this interplay between
technology, developing the proper laser, then doing very
fundamental science, which we're building now,
when we build, for example, quantum computers. So
And, you've also been involved in that company,
AQT. Are you still closely involved in that
on the you know, you're helping to run
that company?
Well, I'm sort of in the the second
row, I have to admit, to this company,
so I'm not directly involved in all of
that. But, of course, I talk a lot
to my colleagues, you know, like Rainer Platt
and Thomas Muntz, who are doing these things.
And, yeah, we have sometimes discussions about where
things are going. And I if my opinion
is a theorist,
very often they have their own opinions, you
know, companies to make money as we said
before.
And,
companies also have to identify certain niches where
they belong. You know? There's a lot of
competition, a lot of startups,
and you have to identify, though, where, for
example, a trapped icon to computer
has unique advantages when it leads to other
possibilities. And there's a lot of companies out
there that have quite a lot of money
for the development.
So you have to identify your corner where
you're the king. Okay? And I think that
this, this can be done. Yeah. Now here
at Helgoland, there have been all sorts of
different talks on all sorts of different areas.
Have there been any ones that you found
particularly interesting or where you've learned something new?
Well, I can list the,
many talks here that I got very excited
about. I mean, I have to say that,
many of the experimental talks were very exciting
for me because they point out the different
platforms. There was a lot here about nano
mechanics, this interface with gravity, like the last
talk that you just
heard now,
here, you know, that was on on on
on gravity and being able to be nanomechanics
to probe fundamental physics along these lines.
And, I think that this is where the
field is developing. And, of course, I'm thinking
now these things in terms of the system
I'm interested in, like, you know, you make
large scale networks of quantum sensors to do
these kind of things. So as the theorist,
the goal is always to identify important problems,
but also see what the experimental developments are
and extrapolating these experimental developments into the future.
You know what, five years down the road,
the experimentalist might be able to do. And
this is then the door opener to completely
new things that are could be game changers.
You know? And this is so picking up,
you know, the progress, picking up interesting topics,
and I would say gravity was a very
strong point of this conference here. Yeah. And,
how active are you still in research? Are
you still doing plenty of research? Are you
almost full time still even though you're normally
retired?
Well, I'm formally retired, but I have to
admit that I go every day to under
cold work, you know, and,
while I'm not allowed to have my own
group anymore, what I do have is that
I have access to some of the other
graduate students from some of the other groups.
I discuss with them. And so,
to the extent that I have interesting ideas,
they also want to listen to me. And
so, yeah, I'm I'm still involved in these
things.
Not like having your own group where you
could always, you know, decide. Okay. Let's do
this thing now and not and not that,
but still on the level where I think
it's interesting. So as long as I have
interesting ideas and I can convince some students
to know that these ideas are interesting and
some postdocs,
you know, they will be collaborators.
So if you were a young student today,
what field would you go into? Would you
stay in quantum physics? And if so, you
know, which area would you go into?
Well, maybe I would say now the obvious.
I mean, quantum physics is now the point
which has changed a lot relative to when
I entered. You know, I decided all of
this quantum computing ideas and business and developing
hardware with atoms and ions and so on.
This was in the middle of the nineties,
and there was then, you know, a very
fruitful period of about maybe ten years where
we came up with a lot of theoretical
ideas.
Today, many of these ideas are reality in
the lab
and sort of, you know, things are changing
now in the sense that, you know, we
thought a lot about hardware, how to build
it, and, you know, how to make it
perfect and what could be done, how to
entangle,
and how these things are here. But we
also had a vision what we wanted to
do with this kind of devices, you know,
like, quantum computing, what problems we want to
solve, like, many body problems for quantum simulation,
whatever it may be. And today is very
fascinating for me. This is somehow a game
changer, and the young
generation finds itself confronted with
that. That, you know, we wrote a lot
of theory papers that it took five years,
maybe even ten years for this thing to
become reality,
in the in the lab because they experimentally
said to start at zero, it really work.
Now these machines exist, and they are programmable
machines. So this means that we can take
our ideas off and just go to these
machines and program these things directly. And,
yeah, we just throw the paper together with,
for example, Queva, you know, the the the
company of of Michelukin,
and so on,
at Harvard,
MIT.
And, we wrote a paper together. It came
out in Nature last week, you know, on
simulating lattice gauge theories. You know, this was
just an outcome like that. It's an interesting
problem. We sort of see how to implement
it on these machines,
and then, well, there's a machine available. And
then you work together, and it takes some
time. You know, it took two and a
half years, but in the end, it's a
positive outcome. You know? Very exciting. Yeah. Mhmm.
There were one or two rumbles at the
conference about the fact that there are two
sponsors from the US military. Does that bother
you at all? Do you have any view
on that?
Well, I would say that, you know, being
physics sort of got used that in The
US, this is very different in Europe.
I know the military are sort of funding
basic science. I think there is maybe a
more
a tradition that is, you know, based on
how science was done emerging then after the
second World War.
So I would say that this is something
it's just maybe more cultural in The US.
I would not take it too seriously,
but I would say that the situation that
we have in Europe, where we have a
very clear distinction, you know, basic science is
funded by the government, by some National Science
Foundation,
and and not by the military, you know,
that this is distinct.
But,
I'm I don't want to criticize my American
friends for that. You know?
But I'm happy that we had a different
situation here. So if we came back to
Holderland in, 2125,
how would you sort of see the quantum
world? What would be on the two hundredth
anniversary of quantum mechanics conference? Have you organizing
it?
Oh,
well, I think the exciting thing is that
we don't know, and we, you know, it
will be much more exciting than we think
right now. And,
I don't know. Maybe this fundamental problem of,
you know, interface of quantum and gravity will
be solved. You know?
I have a little bit doubt about, you
know, understanding
more. There was a lot of discussion here
about foundations that I find interesting, but I
don't work on this myself. Like, the measurement
problem and so on, it seems to be
very hard to make progress. And I believe
progress in physics is made at the end
by doing experiments,
you know, building apparatus that allow to do
new kind of experiments.
And these are then the ones that at
the end, you know, surprise us by new
results. And once we have
experimental evidence in whatever sense, you know, this
is guiding our
our understanding and our our development of theory
and, you know, it's sort of the next
step. Yeah. I always find it remarkable to
think that Heisenberg was 23 when he did
all that amazing work. You know, is there
is there still an open field for young
people to do those kind of big breakthroughs
that he had?
Well, I would say that, you know,
at the time of Heisenberg, Heisenberg was, of
course, I mean, one hand very clever, and
the other hand, he was very lucky
because, you know, in the physics,
there's often periods, and I would say that
the creation of quantum mechanics was one of
them, where there was sort of a problem
was was was ripe to be solved, you
know, ready to be solved. And the most
clever people, you know, that just were there
at that time, you know, they were they
made the seminal contribution within a few years.
Think about Schrodinger who you know? And, again,
it was '25, I think, in December, and
I also wrote down the Schrodinger equation, solved
the hydrogen problem, and all then found afterwards,
well, that his wave mechanics was equivalent to
matrix mechanics. So there was a lot of
clever people around, but there was also problems
that are ready to be solved. And, this
does not always happen. Not to say that
I myself considered to be very lucky because,
you know, I was working on quantum optics
at dummy physics at the time where, well,
it was kind of interesting.
But then quantum computing came along, and, you
know, we were just had our tools ready,
our ideas ready.
You know, and, like, if you'd look at
trapped ion quantum computing, you know, we were
working on that before. We just didn't know
that you would also access your computer. It'd
be very interesting. You know? So very often
you work on something and you're sort of
surprised. Well, this is actually
looking from a different angle, much more interesting
than I ever thought. So this element of
being lucky and surprising and but also having
the right discussion partners and going to the
right conferences like, yeah, I know it can
be the
the insider for that.
I was just sort of a a final
question. If you could imagine going back in
time, if would there be any figures from
the early years of quantum physics that you'd
like to meet? And what would you ask
them if you had the choice to meet
one of those people?
Well, it's interesting for us when we start
reading some of these old papers, you know,
most of them still written in German and
always has changed some time later,
that, it would be very interesting to discuss
them. And, like, for example, being here and
asking Heisenberg
and
how he really saw these things. I know
very often in in in in retrospect,
these stories, this history,
I mean, is somehow,
written then in a certain way, which is
maybe not 100% how it happened. I think
there were much more fluctuations and sort of
uncertainties. And Heisenberg, on one hand, was a
genius. On the other hand, if you read
his first paper,
I was saying, how the hell did he
ever write these things down? And how could
out of this thing then emerge something that
was so fundamental and they'd be working on
today
and which is experimentally confirmed on all these
levels. So, yeah, I'd very much like to
talk to these people. Yeah. So may maybe
Heisenberg. Well, because I would be really fascinated.
You know, he came here with just a
pen and paper, no Yeah. No Internet and
no phone, no television, no computing, and he
did all that work with just nothing, just
coming on his own. It's just, you know,
horrible to think. Yeah. That's right. Yeah. I
mean, I have to say that for me,
Schrodinger writing down the Schrodinger equation
is sort of something where you say, well,
it's pretty obvious. As a physicist, you know,
There was, de Broglie and over the,
that there would
be waves, you know, matter waves, and there's
a dispersion relation.
He asked them, you know, what is the
corresponding wave equation, then writing it down, and
then him solving it for the hydrogen atom.
And it was a problem incoming from acoustics,
for example. He knew how to solve eigenvalue
problems, and so the hydrogen was just one
of a different type, very complicated, but he
could do it analytically, you know, while being
on on winter vacation in Ouse.
So this is,
this is for me much more logical. But
Heisenberg's,
no entry to quantum mechanics with this matrix
mechanics, I find it very mysterious. You know?
Well, we'll leave it there. Fantastic mystery to
end on. Thank you, Peter.
That was Physics World's Mateen Durrani in conversation
with Peter Zoller. And before that, you heard
Michelle Simmons
and Tracy Northup.
The Helgoland
conference is one of many events worldwide
that are celebrating
2025
as the international
year of quantum
science and technology
as decreed by the United Nations
Educational,
Scientific,
and Cultural Organization,
better known as UNESCO.
We've been celebrating here at Physics World throughout
the year, and you can find all of
our special
quantum coverage
by going to our website
and clicking on quantum
under the topics tab.
I'm afraid that's all the time we have
for this week's podcast. Thanks to Michelle Simmons,
Peter Zoller, and Tracy Northup for their reflections
on the past, present, and future of quantum
physics,
and to Matin Jurani for making the epic
journey to Helga Land on behalf of Physics
World.
And as always, a special thanks to our
producer,
Fred Isles.
We'll be back again next week. See you
then.