Jan
11
The Hype Over Quantum Computers, Explained


Quantum computers use the natural
world to produce machines with staggeringly powerful
processing potential. I think it’s gonna be
the most important computing technology of this century, which
we are really just about one fifth into. We could use quantum computers
to simulate molecules, to build new drugs and new
materials and to solve problems plaguing physicists
for decades. Wall Street could use them
to optimize portfolios, simulate economic forecasts and for
complex risk analysis. Quantum computing could also
help scientists speed up discoveries in adjacent fields
like machine learning and artificial intelligence. Amazon, Google, IBM and Microsoft,
plus a host of smaller companies such as Rigetti and
D-Wave, are all betting big on Quantum. If you were a
billionaire, how many of your billion would you give over for
an extra 10 years of life? There are some simply
astonishing financial opportunities in quantum computing. This is
why there’s so much interest. Even though it’s so
far down the road. But nothing is ever
a sure thing. And dealing with the quirky
nature of quantum physics creates some big hurdles
for this nascent technology. From the very beginning, it
was understood that building a useful quantum computer was going
to be a staggeringly hard engineering problem if it was
even possible at all. And there were even distinguished
physicists in the 90s who said this will never work. Is Quantum truly the next big
thing in computing, or is it destined to become something
more like nuclear fusion? Destined to always be the
technology of the future, never the present. In October 2019,
Google made a big announcement. Google said it
had achieved quantum supremacy. That’s the moment
when quantum computers can beat out the world’s
most powerful supercomputers for certain tasks. They have demonstrated with a
quantum computer that it can perform a computation
in seconds. What would take the
world’s fastest supercomputer? Years, thousands of years to
do that same calculation. And in the field, this is
known as quantum supremacy and it’s a really
important milestone. Google used a 53 qubit
processor named Sycamore to complete the computation, a
completely arbitrary mathematical problem with no
real world application. The Google Quantum computer spit out
an answer in about 200 seconds. It would have taken
the world’s fastest computer around 10000 years to come up
with a solution, according to Google scientists. With that, Google claimed it had
won the race to quantum supremacy. But IBM had an
issue with the findings. Yes, IBM, the storied tech
company that helped usher in giant mainframes and
personal computing. It’s a major player
in quantum computing. IBM said one of its
massive supercomputer networks, this one at the Oak Ridge
National Laboratories in Tennessee, could simulate a quantum
computer and theoretically solve the same problem in a matter
of days, not the 10000 years that Google had claimed. Either
way, it was a huge milestone for quantum computers,
and Silicon Valley is taking notice. Venture capital
investors are pouring hundreds of millions of
dollars into quantum computing startups, even though practical
applications are years or even decades away by 2019. Private investors have backed
at least 52 quantum technology companies around the
world since 2012, according to an analysis by nature. Many of them were spun
out of research teams at universities in 2017 and 2018. Companies received at least $450
million in private funding more than four times the
funding from the previous two years. That’s nowhere near the
amount of funding going into a field like
artificial intelligence. About $9.3 billion with a venture capital
money poured into AI firms in 2018. But the growth
in quantum computing funding is happening quickly for an
industry without a real application. Yet it is not easy
to figure out how to actually use a quantum computer
to do something useful. So nature gives you this very,
very bizarre hammer in the form of these this interference
effect among all of these amplitudes. Right. And it’s up to us as
quantum computer scientists to figure out what nails that
hammer can hit. That’s leading to some backlash
against the hype and concern that quantum computing could
soon become a bubble and then dry up just
as fast if progress stalls. Quantum computers are
also notoriously fickle. They need tightly controlled
environments to operate in. Changes in nearby temperatures
and electromagnetic waves can cause them to mess up. And then there’s the temperature
of the quantum chips themselves. They need to be
kept at temperatures colder than interstellar space, close
to absolute zero. One of the central tenets
of quantum physics is called superposition. That means a
subatomic particle like an electron can exist in two
different states at the same time. It was and still is
super hard for normal computers to simulate quantum mechanics
because of superposition. No, it was only in the
early eighties that a few physicists, such as Richard
Feynman had the amazing suggestion that if nature is
giving us that computational lemon, well, why not
make it into lemonade? You’ve probably heard or read
this explanation of how a quantum computer works. Regular or classical computers
run on bits. Bits can either be a
1 or a zero. Quantum computers, on the other
hand, run on quantum bits or cubits. Cubits can be either 1
or zero or both or a combination of the two
at the same time. That’s not wrong per say,
but it only scratches the surface. According to Scott
Aaronson, who teaches computer science and quantum computing at
the University of Texas in Austin. We asked him to
explain how quantum computing actually works. Well, let
me start with this. You never hear your weather
forecaster say we know there’s a negative 30 percent
chance of rain tomorrow. Right. That would just
be non-sense, right? Did the chance of something
happening, as always, between 0 percent and 100 percent. But now quantum mechanics is
based on numbers called amplitudes. Amplitudes can be
positive or negative. In fact, they can even
be complex numbers involving the square root of negative one. So so a qubit is a bit
that has an amplitude for being zero and another amplitude
for being one. The goal for quantum computers
is to make sure the amplitudes leading to wrong answers
cancel each other out. And it scientists reading the
output of the quantum computers are left with amplitudes
leading to the right answer of whatever problem
they’re trying to solve. So what does a quantum computer
look like in the real world? The quantum computers developed
by companies such as Google, IBM and Rigetti were
all made using a process called superconducting And this is where you have a
chip the size of an ordinary computer chip and you have little
coils of wire in the chip, you know, which are
actually quite enormous by the standards of cubits. There are, you know, nearly big
enough to see with the naked eye. But you can have
two different quantum states of current that are flowing
through these coils that correspond to a zero or a one. And of course, you can also
have super positions of the two. Now the coil can
interact with each other via something called
Josef’s injunctions. So they’re laid out in roughly
a rectangular array and the nearby ones can talk to
each other and thereby generate these very complicated states,
what we call entangled states, which is one of
the essentials of quantum computing and the way that the cubists
interact with each other is fully programmable. OK. So you can send electrical
signals to the chip to say which cube it should interact with
each other ones at which time. Now the order for this
to work, the whole chip is placed in that
evolution refrigerator. That’s the size of
a closet roughly. And the calls it do about
one hundredth of a degree above absolute zero. That’s where
you get the superconductivity that allows these bits to
briefly behave as cubits. And IBM’s research lab in
Yorktown Heights, New York, the big tech company, houses
several quantum computers already hooked up to the cloud.
Corporate clients such as Goldman Sachs and JP Morgan are part
of IBM’s Q Network, where they can experiment with the
quantum machines and their programming language. So far, it’s a way for
companies to get used to quantum computing rather than make
money from it. Quantum computers need exponentially
more cubits before they start doing
anything useful. IBM recently unveiled a fifty
three cubic computer the same size as Google’s
sycamore processor. We think we’re actually going
to need tens of thousands, hundreds of thousands of qubits
to get to real business problems. So you can see quite
a lot of advances and doubling every year or perhaps even
a little faster is what we need to get us there. That’s
why it’s 10 years out, at least. Quantum computing would need to
see some big advances between then and now, bigger
advances than what occurred during the timeline of classical
computing and Moore’s Law. Oh, we need better
than Moore’s Law. Moore’s Law is doubling
every two years. We’re talking doubling
every year. And occasionally some
really big jumps. So what’s quantum
computers become useful? What can they do? Scientists first
came up with the idea for quantum computers as a
way to better simulate quantum mechanics. That’s still the
main purpose for them. And it also holds
the most moneymaking potential. So one example is
the caffeine molecule. Now, if you’re like me,
you’ve probably ingested billions or trillions of. Caffeine
molecules so far today. Now, if computers are really
that good, really that powerful. We have these
these tremendous supercomputers that are out there. We should
be able to really take a molecule and represented exactly
in a computer. And this would be great
for many fields, health care, pharmaceuticals, creating new
materials, creating new flavorings anywhere where molecules
are in play. So if we just start with
this basic idea of caffeine, it turns out it’s absolutely
impossible to represent one simple little caffeine molecule
in a classical computer because the amount of information
you would need to represent it, the number of zeros
and ones you would need is around ten to forty eight. Now, that’s a big number. That’s
one with forty eight zeros following it. The number of atoms
in the earth are about 10 to 100 times that number. So in the worst case, one
caffeine molecule could use 10 percent of all the atoms in
the earth just for storage. That’s never going to happen. However, if we have a quantum
computer with one hundred and sixty cubits and this is a
model of a 50 kubert machine behind me, you can kind of
figure, well, if we make good progress, eventually we’ll get up
to 160 good cubits. It looks like we’ll be able
to do something with caffeine, a quantum computer, and it’s
never going to be possible. Classical computer and other potential
use comes from Wall Street. Complex risk analysis
and economic forecasting. Quantum computing also has
big potential for portfolio optimization. Perhaps the biggest
business opportunity out of quantum computing in the
short term is simply preparing for the widespread
use of them. Companies and governments are
already attempting to quantum proof their most sensitive
data and secrets. In 1994, a scientist at Bell
Labs named Peter Shaw came up with an algorithm that
proved quantum computers could factor huge numbers much more
quickly than their classical counterparts. That also means
quantum computers is powerful and efficient enough could
theoretically break RSA encryption. RSA is the type
of encryption that underpins the entire internet. Quantum computers, the way they’re
built now, would need millions of cubits to
crack RSA cryptography. But that milestone could be 20
or 30 years away and governments and companies are beginning
to get ready for it. For a lot of
people, that doesn’t matter. But for example, for health
records, if health records to be opened up that could
compromise all kinds of things. Government communications.
Banking records. Sometimes even banking records
from decades ago contain important information that you
don’t want exposed. But the problem we’ve got is
we don’t really know when we’ll be able to do this or
even if we’ll ever build one big enough to do this. But what we do now, is
that if you don’t update your cryptography now, all the messages
you send over the next few years and the ones
in history could potentially be read. What this means, for example,
is if you’re a Cisco selling networking equipment, you’re
going to offer quantum-safe encryption as an option
in the very near future. Becayse even though it
doesn’t look like you need it right away. If your product
doesn’t have it and a competitor does, guess which
product gets bought? One big issue facing
quantum computing, other than increasing the number of
cubits while keeping things stable, is that no one actually
knows the best way to build a quantum computer. Yet the
Quantum computers, a Google of IBM and other companies show
off are very much still experiments. There’s also a
big education gap. Not many people are
studying quantum computing yet. China is pouring billions
into quantum computing education, and the U.S. Congress passed a
law in 2018 called the National Quantum Initiative Act in
order to help catch up watching people get
rid of him. Which means that you want
to invest in them now. You want to be hiring
people with quantum computing knowledge. Not necessarily to
do quantum computing, but because you want that intelligence
in your organisation so you can take advantage of
it when it shows up. Now China, with its promised $10
billion in it, is really upping stakes in terms of
the number of Chinese quantum physics PhDs that are
going to start appearing. And you know if that
hair restoration or life extension drug happens to be property
of the Chinese government, what does that do to
the world economy? That’s much more powerful than
making war Other experts have compared Google’s announcement
to Sputnik, the Soviet satellite launched into
orbit in 1957. The beach ball sized satellite
was the first manmade object to orbit the Earth. But
Sputnik didn’t really do anything useful other than prove launching
something into space was possible. Many people are surprised
that where exactly we are. For those who are just
getting started, they like to make noise about vacuum tubes
and Sputnik and things like this. But let me
give you some numbers. IBM has had quantum computers on
the cloud for three and a half years since May of 2016. We’re not in any
sort of Sputnik error. We’re not landing on the moon. But for those of you who
like space history, I think we’re probably well into
Mercury or Gemini.