Or: how will I interact with a quantum computer, and what can it do?

Interior of IBM Quantum computing system. Photo by .

The greater the functionality of a tool, the less efficient it will be for any given task. Take, for example, The Giant, which earns the title of . It is a Swiss Army knife with 87 tools. It is over 8 inches long and weighs 3 pounds.


Or: how to do multiplication on a quantum computer today

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What you will read here is a bad idea. Don’t try this at home. You’ve been warned. I’ll be using a metaphorical sledgehammer to crack a hypothetical nut. I am trying to do a much, much lamer version of using a drone to change a light bulb.


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First, some definitions (as told to me by Google).

Scientist: a person who is studying or has expert knowledge of one or more of the natural or physical sciences.

Scientologist: a person who believes that human beings are immortal, that a person’s life experience transcends a single lifetime, and that human beings possess infinite capabilities .

Scientistic: a person with excessive belief in the power of scientific knowledge and techniques.

While a person is quite capable of being a scientist and a serial killer, let’s suppose for the sake of argument we are talking about people that can be defined…


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I have two friends, Alice and Bob. Soon they will be your friends. Since I’m a nice guy, I’m going to give each of them a gift. It’s nothing special — just a box with a couple of buttons and lights on it.


Welcome to Introduction to Quantum Computing. I am your guide,, a researcher in the. This is Lecture 9.

It would probably be a good idea to have read the previous Lectures before continuing.

What did you learn last week?
Last week you learned about the high-level structure of quantum algorithms, especially those with oracles. You’ve also seen the detailed implementation of the Deutsch-Jozsa algorithm and how it makes use of the quantum primitives: superposition, quantum logic, phase logic, and uncomputation.
What will you learn this week?
This week you will…


A tutorial for the virtual workshop

Recorded lecture. Warning: this a 1-hour video!

This is a bit awkward. You are watching a recorded video. Some of you are watching it “live” at the workshop while I sleep — since it is the middle of the night here in Sydney. Perhaps, though, this video will be posted and sit on the internet somewhere in perpetuity. …


A Physicist’s Valentine’s Day Poem

Roses are red.
Violets are blue.
My heart loves all,
The quantum in you.

Nitrogen, calcium,
And phosphorus.
There’s so much in common,
Between two of us.

Hydrogen, carbon,
And oxygen.
There’s a lot going on,
Under your skin.

From your head to your toes,
You’re made of this stuff.
To look on the outside,
Is never enough.

Inside and out,
Atoms and space,
To think of them all,
Makes my heart race.

Within each element,
There’s more going on.
Protons, neutrons,
And electrons.

Go deeper still,
And you will find quarks —
The building blocks,
Which…


Or, what would Quantum Mario Bros. look like?

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During a lecture for , the topic of the came up. We’ll get into the details of this, but essentially it says that — unlike a “watched pot” which eventually boils — a “watched quantum pot” never does boil. One of the students asked if this was similar to how Boo works in Super Mario Bros. The answer is almost, but no. However, we can use Boo to learn about quantum physics anyway!

Only 90’s kids

Nineties kids and younger millennial hipsters will have fond memories of , the…


And what it can teach you about quantum physics

I made this. I’m not all that proud of it to be honest.

Four quantum physicists are in a car. Heisenberg is driving like he is in The Matrix. Schrödinger is in the front seat waving at the other cars. Einstein and Bohr are in the back arguing when they get pulled over. The officer asks Heisenberg, “do you know how fast you were going?”

“No, but we know exactly where we are,” Heisenberg replies.

The officer looks confused and says, “you were going 120 km/h!”

Heisenberg throws his arms up and cries, “Great! Now we’re lost!”

The officer looks over the car and asks Schrödinger if they have anything in the trunk…


A gentle introduction to quantum tomography

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This lecture was given as part of series on Hackaday organised by . Kitty has drawn an of this lecture as well! The recording of this lecture is available on Kitty’s YouTube channel:

Who are you?

You’ve done a bit of self-study. You’ve participated in quantum technology lectures. You’ve got an awesome certificate from Kitty — and had it printed on a mug! Maybe you’ve even implemented a quantum algorithm on a cloud-based quantum computer. By all accounts, you’re a quantum coder. That’s great, because I have a problem. Someone gave me this…

Chris Ferrie

Quantum theorist by day, father by night. Occasionally moonlights as a children’s book author. @csferrie

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