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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.