# Trudeau versus the experts: Quantum computing in 35 seconds

We challenged seven physics experts to explain quantum computing to the rest of us, in the time it took Justin Trudeau to do so

When Prime Minister Justin Trudeau visited the Perimeter Institute for Theoretical Physics in Waterloo, Ont. last week and offered his explanation for how a quantum computer works, it sparked intense media coverage from around the world. It also led to a backlash over whether Trudeau really knew anything about the cutting-edge technology, or was just pretending.

But what happens when experts in quantum computing themselves are asked to explain the technology to a lay audience in 35 seconds, the time Trudeau took to give his explanation? “This is something that cannot be explained well in 35 seconds,” says Aephraim Steinberg, a professor of physics at the University of Toronto and member of the Centre for Quantum Information and Quantum Control. But Steinberg—and a half-dozen other experts from across North America—were willing to step up to our challenge and give it a try.

Related:Paul Wells on that quantum question, and what happens in a scrum

### Barry Sanders

#### Director of the Institute for Quantum Information Science at the University of Calgary

“A quantum computer is essentially just a computer, but it exploits the quantum capability of parallelism in order to solve certain problems much much faster than could be done without exploiting this capability. This quantum capability of parallelism is about running all possible cases of the problem at the same time. This advantage is particularly noticeable for the factorization problem, which has enormous ramification for secure communication.”

### Krysta Svore

#### Senior researcher and research manager of the Quantum Architectures and Computation Group at Microsoft Research

“Quantum computers go beyond the most powerful supercomputer by harnessing quantum effects in order to speed up calculations. They will take us far beyond what is possible today by accelerating computations that take longer than the lifetime of the universe on a supercomputer into quantum computations that take mere hours or days. With a quantum computer, we hope to find a more efficient way to produce artificial fertilizer, having direct impact on food production around the world, and we hope to combat global warming by learning how to efficiently extract carbon dioxide from the environment. Quantum computers promise to truly transform our world.”

### Scott Aaronson

#### Associate professor of electrical engineering and computer science at the Massachusetts Institute of Technology (MIT)

A quantum computer is a proposed device that exploits quantum mechanics to solve certain specific problems like factoring huge numbers much faster than we know how to solve them with any existing computer. Quantum mechanics has been the basic framework of physics since the 1920s. It’s a generalization of the rules of probability themselves. From day to day life, you’d never talk about a minus-20 per cent chance of something happening, but quantum mechanics is based on numbers called amplitudes, which can be positive or negative or even complex numbers. The goal in quantum computing is to choreograph things so that some paths leading to a wrong answer have positive amplitudes and others have negative amplitudes, so on the whole they cancel out and the wrong answer is not observed.

### Davide Venturelli

#### Research scientist at NASA Ames Research Centre

“When you look at how nature behaves at the nanoscale, a lot of things that happen are very weird: atoms can be in two positions at once, they can have entanglement. The idea of quantum computing is to use physics to do math, so use all these properties of the nanoscale to do information processing, faster than digital computers. We are trying to create a quantum computer, which is a programmable device where we can use all these effects on-demand to tailor physics experiments, with atoms, lasers or solid state circuits, that perform algorithms for the solutions of mathematical problems.”

### Martin Laforest

#### Senior manager, scientific outreach at the Institute for Quantum Computing at the University of Waterloo

“The thing with quantum computing is that we are literally turning the rules of computing on its head. By using quantum bits instead of regular bits, we can exploit phenomena that are unique to the world of atoms and molecules, like quantum superposition and quantum entanglement. This gives us a radically different environment for computing and allows us to solve certain problems much more quickly than on traditional computers. An interesting quantum phenomenon that quantum computers exploit is quantum interference. For example, we can devise quantum algorithms such that all the possible ways to get to the wrong answer interfere with themselves and cancel each other out, while leaving only the possibility of getting to the right answer.”

### Murray Thom

#### Director of professional services at D-Wave Systems, Inc. a quantum computing company, based in Burnaby, B.C.

“What is a quantum computer? When you think about a computer, at the centre of it is a processor that’s making calculations for you. A quantum computer can use quantum mechanics to help perform those calculations. A classical computer also has quantum mechanics at play but it can actually interfere with the information you’re trying to process by causing bit flip errors or leakage currents. So once you design a computer with a processor that can use quantum mechanics to help you with those calculations, that’s what sets it apart from all the other computers on the planet.”

### Aephraim Steinberg

#### Professor of physics at the University of Toronto and member of the Centre for Quantum Information and Quantum Control

“In the past, we believed all computers fundamentally did the same thing—just maybe one a bit faster than another. Now, as far as we can tell, this is just wrong. In the quantum world, information simply behaves differently from in the classical world. If a system, whether an electron or a computer, can be in two or a million different states, it can also be in what we call a superposition of all those states, and that gives it much more room to maneuver to try to get from input to output. It’s as though you’re Houdini trying to pick a lock and escape from an underwater cabinet. If you were free to move your hands wherever you’d like, you could do so much more efficiently than if you were handcuffed. It’s not just a question of moving more quickly. It’s a question of moving in different ways.”

### Justin Trudeau

#### Prime Minister of Canada, and hardly an expert

“Normal computers work, either there’s power going through a wire or not. It’s 1 or a 0. They’re binary systems. What quantum states allow for is much more complex information to be encoded into a single bit. A regular computer bit is either a 1 or 0—on or off. A quantum state can be much more complex than that because as we know, things can be both particle and wave at the same time and the uncertainty around quantum states allows us to encode more information into a much smaller computer. That’s what exciting about quantum computing.”

Regardless of how Trudeau’s explanation compares to the experts, those working to develop quantum computers can at least take one thing from Trudeau’s quantum leap—exposure like the sector has never had before.

This story has made headlines around the world, I hope it gains us some new scientists

It’s a far cry from the days when our scientists had to protest government censorship

Emilyone on

Umm…..I am sure that by now, most folks realize that the entire “question and answer” session about quantum computing was a set-up arranged by Trudeau and his folks right?

Trudeau didn’t / doesn’t know squat about quantum anything…..but he did memorize a few lines he had been told before the questions he asked to be asked….was asked.

Of course, I’m sure that Aaron Hutchins…was completely unaware of this part of the story. For if he did know about it, it would surely show he’s just another Canadian media sycophant who can’t be trusted to write anything about Liberals or Trudeau from this point forward. You can’t be trusted to write truthful stories that may be negative, if your subject is the same person you worship at the altar you have created in your newsroom.

Just saying.

(I’m sure the censors at Macleans will get rid of this one in a hurry)

JamesHalifax on

Right … because you really know the whole inside story on this event … you are the ultimate insider on all things Liberal party/Trudeau/Government of Canada … you’re that important … that’s why you hang around here all day spouting your anti- liberal, anti-left, anti-anything not related to your beloved Harper and conservative party.

mellor on

Actally, Mellor,

If you read anything other than this blog site for Macleans, you would know that what I wrote above is true. In fact, it is in today’s National Post.

but you go ahead and keep on believing what you want to believe…no skin off my back.

JamesHalifax on

Nevertheless, I agree with MELLOR.

Just saying.

B.Causeiknow on

Colour me surprised.

by the way….if you see Mellor on a bridge….you don’t have to follow his lead.

JamesHalifax on

He did teach math- and is interested in science- (spent a lot of time at W of W touring labs and talking to students and professors) He did answer the ‘rest” of the question about ISIS as well.

I am so pleased to see a PM who is interested in the science of the future.

Peg's view on

First, classical computers are controlled by voltage, not current (power) flowing, that’s why they don’t melt. Second, he did not mention that quantum computers (in theory, sorry D-Wave) work by exploring all the possibilites at once, thus bringing exponential time algorithms down to polynomial time. Thrudeau’s propaganda crew should be more precise.

Boci Boci Tarka on

Bravo, there are independent thinkers. :) Thanks for bringing that to light Boci. :)

Sharon Riordan on

It seems that the senior quantum scientists quoted didn’t mention that either.

B.Causeiknow on

This story gets funnier by the moment

For one thing, we have all seen the video, where Justin tells the reporters to ask him a question on quantum computing, so there is no subterfuge about it

The perimeter institute is not in need of money folks, so nobody is sucking up. NOW you’re complaining Trudeau’s explanation wasn’t technical enough LOL

It was a general explanation for a general TV audience…and a brilliant publicity move.

This is the kind of silly partisanship that got your con party kicked out on their arse

Emilyone on

Yes, we have all seen the clip where Justin says he sure hopes a reporter will ask him a question about quantum physics. The reporter says, I won’t ask you about quantum physics but rather about ISIL and asks what Justin is doing with regard to ISIL at the present time. Justin then starts into his explanation about quantum physics which he learned during his tour of the facility. Everyone laughed because even though the reporter never asked the question, Justin really wanted to tell what he learned.

Now, perhaps you can clarify whether it is true that Justin skipped the emergency parliamentary debate on Attawapiskat to take his family out for dinner. This is being reported in the Huffington Post. I know how concerned you are for First Nations people and I know that Justin said they are his priority so maybe you can explain his behavior.

Gage G. on

Not being able to score on computers, you are now trying to divert it to dinner

I believe the debate went on till midnight, Justin was there

What next, you don’t like the colour of his shoelaces?

Emilyone on

“Not being able to score on computers”

What do you mean?

Sully99 on

Gage,

Trudeau has already shown his “Attiwapiskat” bona-fides.

Don’t you remember his maudlin display in the tent outside Parliament hill when he was commiserating with “Big chief double-chin-starving in tent” ?

The rest of Attawapiskat’s issues will be dealt with by the underlings. Unless of course, an opportunity for a good photo-op arises. Then he’ll be there will bell (bottoms) on and his selfie-stick.

JamesHalifax on

The Harper supporters are still so bitter. Don’t know how long it will take for them to get over the election.

Hopefully they can get behind the ‘new’ PC leader- when they decide on one.

I imagine the race will become a bloodbath. Kelly Leitch is already weeping over the ‘children” and the fact that she didn’t make her “Hotline speech” at an opportune moment.

Peg's view on

With respect to Mr. Trudeau — even if it was a rehearsed explanation, it was better than most of us could manage, and most other politicians wouldn’t bother — the recent jolt in interest in quantum computing is not a result of the present controversy over his statement, as the article suggests. There has been a great deal about the subject in the science pages of various newspapers this year. Perhaps we should take more satisfaction from the fact that Waterloo keeps getting mentioned.

You're right, but... on

When will you ass kiss morons learn that PM Buttercup knows absolutely nothing about quantum physics. He does remember lines fed to him very well though, (see every line he’s regurgitated since 19 Oct 2015). But the knuckle dragging media still fawn over his numbnutness.

lespaul on

Instead of 1’s and 0’s we have ABC to Z and AA BB CC to ZZ ect. as routes if you will to the correct answer. Ones and Zeros are history.

Rick De B. on