Journal | October 2018

Happy Halloween! We escaped the cold in Canada and are now back in Australia, ready for second summer 😁


The big aha! moment was seeing how much stories resonate with parents! Over the past year and a half, I’ve been reading from Rocket Science for Babies and doing some paper activities (paper airplanes, demonstrating lift, etc.). It’s been great and I think the children have lots of fun. But because it’s mostly an interaction between me and the children, perhaps some parents feel left out? Or, maybe they are just happy to sit back let their children take the lead.

This month, though, I started reading 8 Little Planets at events as well, and the response from the parents was amazing! Nothing like a good story to excite the imaginative child in all of us, I guess 😁

This month I also got some hilarious feedback on social media. Here are a few highlights:


Children’s Literature Recommendations

What do you do with a problem by Kobi Yamada, Illustrated by Mae Besom

Inspirational story about a young person tackling a problem head on and finding beauty in it. It’s a bit abstract, meaning it might take a while for a child to “get it”, but the illustrations are beautiful and the pace was right for a bedtime read.

The Atlas Obscura Explorer’s Guide for the World’s Most Adventurous Kid by Dylan Thuras and Rosemary Mosco

I think adults will find this more amusing than children. My guess is that these real places are suppose to be surprisingly, well, obscure. But, to a child, these are just slightly less fantastic than what they can dream up in their own imagination. It can still keep a child’s attention and led to some interesting questions.

Amulet: The Stonekeeper by Kazu Kibuishi

I was skeptical about reading a graphic novel aloud, especially the pages with no words! But, it actually worked quite well. Even the non-readers could understand the plot. The story itself is amazing. We all can’t wait to continue the series.

Adult Literature September Reads

Scale: The Universal Laws of Life, Growth, and Death in Organisms, Cities, and Companies by Geoffrey West

This one is about the science of complexity and some simple rules that govern how things (from animals to suburbia) scale. There are lots of interesting tidbits in here. My favorite is an understanding, using scaling laws, for why every species of mammal has the same number of heartbeats over their lifetime, from the tiny shrew to the enormous blue whale. It can get a bit wordy and repetitive, but still worth a read.

Currently reading: This Idea Is Brilliant: Lost, Overlooked, and Underappreciated Scientific Concepts Everyone Should Know by John Brockman


Big news this month was the release of 8 Little Planets! It’s super-fun and has amazing illustrations by Lizzy Doyle.

Next up is Blockchain for Babies by my UTS colleague, and blockchain expert, Marco Tomamichel. Just in time for the new year and next Bitcoin boom. HODL on for this one! It’s due 1 Jan 2019.

In terms of writing, I am working on a new ABC’s book. I don’t want to give away the details yet, but here’s a hint: it’s not a STEM topic!

Arithmetic! (academic news)

Last week I attended Quantum Gates, Jumps, and Machines, which was a workshop in honor of Gerard Milburn’s 60th birthday. If you ever get a chance to go to a “birthday workshop”, do it. The talks have great science alongside hilarious anecdotes and roasts of the guest of honor. Barry Sanders documented much of it on Twitter.

University of Technology Sydney will soon offer some undergraduate credit subjects in Quantum Computing. We’ve been having some high level discussion about organizing that and getting it approved through all the bureaucratic channels. There may even be some associated online content! Keep your eyes peeled next Spring term!

After submitting their papers, the students in the group are learning hands on the joys of peer review, including what to do about “interesting” referee reports! Look out for some publications soon.

An Honors student at the University of New South Wales submitted a thesis that I co-supervised. This was my first time officially supervising an undergraduate. It was a very rewarding process as the student was from outside of the field and wrote a thesis on quantum learning applications in statistics.


  • I read and signed some books at the Vancouver Public Library to some excited preschoolers.

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Fun at the Vancouver Public Library!

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  • Byrne and Wade from Sci-gasm Podcast came by the office and we recorded a not-so-family-friendly interview. Stay tuned for that—you might even win a signed copy of Quantum Computing for Babies.
  • Where the Wild Things Are bookshop in Brisbane hosted an event where I read and did some activities with some West Enders. I always have a good time in Brissie!
  • I joined a panel at UTS about Communicating as a researcher: Strategies for building value and reputation. It was quite interesting to contrast my fake-it-before-you-make-it style with one that was more structured, and another that was goal-oriented. Perhaps there is a useful middle ground?

Up next!

In November I’ll be visiting Melbourne and Perth. Come on out and get your science on 6 Nov!

New papers dance!

Two new papers were recently posted on the arXiv with my first two official PhD students since becoming a faculty member! The earlier paper is titled Efficient online quantum state estimation using a matrix-exponentiated gradient method by Akram Youssry and the more recent paper is Minimax quantum state estimation under Bregman divergence by Maria Quadeer. Both papers are co-authored by Marco Tomamichel and are on the topic of quantum tomography. If you want an expert’s summary of each, look no further than the abstracts. Here, I want to give a slightly more popular summary of the work.

Efficient online quantum state estimation using a matrix-exponentiated gradient method

This work is about a practical algorithm for online quantum tomography. Let’s unpack that. First, the term work. Akram did most of that. Algorithm can be understood to be synonymous with method or approach. It’s just a way, among many possibilities, to do a thing. The thing is called quantum tomography. It’s online because it works on-the-fly as opposed to after-the-fact.

Quantum tomography refers to the problem of assigning a description to physical system that is consistent with the laws of quantum physics. The context of the problem is one of data analysis. It is assumed that experiments on this to-be-determine physical system will be made and the results of measurements are all that will be available. From those measurement results, one needs to assign a mathematical object to the physical system, called the quantum state. So, another phrase for quantum tomography is quantum state estimation.

The laws of quantum physics are painfully abstract and tricky to deal with. Usually, then, quantum state estimation proceeds in two steps: first, get a crude idea of what’s going on, and then find something nearby which satisfies the quantum constraints. The new method we propose automatically satisfies the quantum constraints and is thus more efficient. Akram proved this and performed many simulations of the algorithm doing its thing.

Minimax quantum state estimation under Bregman divergence

This work is more theoretical. You might call it mathematical quantum statistics… quantum mathematical statistics? It doesn’t yet have a name. Anyway, it definitely has those three things in it. The topic is quantum tomography again, but the focus is different. Whereas for the above paper the problem was to devise an algorithm that works fast, the goal here was to understand what the best algorithm can achieve (independent of how fast it might be).

Work along these lines in the past considered a single figure of merit, the thing the defines what “best” means. In this work Maria looked at general figures of merit called Bregman divergences. She proved several theorems about the optimal algorithm and the optimal measurement strategy. For the smallest quantum system, a qubit, a complete answer was worked out in concrete detail.

Both Maria and Akram are presenting their work next week at AQIS 2018 in Nagoya, Japan.