Quantum Computing

Quantum Algorithms

My Quantum Computing Wish List for Christmas 2019 and New Year 2020

Here’s a list of all of the quantum computing developments I want to see for Christmas in 2019. Okay, that’s too tall an order with too little time left, so this informal paper lists the quantum computing developments I really want to see in the coming year, 2020. It’s a fun list, but it’s also a real list — these are advances that have a realistic chance of occurring over the coming year. And I have a separate list later in this paper for more adventurous wishes which are much less likely to transpire. And a third list of industry developments I expect but am not excited enough about to put on my own personal wish list.

All I want to see for Christmas in 2019 are:

1. Rigetti to finally deliver their 128-qubit machine. They just came out with 32 qubits, so I will likely have to wait longer.
2. Google to deliver their 72-qubit machine. Or at least something beyond 53 qubits.
3. IonQ to deliver a 79-qubit machine — or anything over 20 qubits.
4. Any real quantum computer from Honeywell.
5. The next leap above 53 qubits from IBM.
6. A doubling of coherence time. Or more.
7. A doubling of maximum circuit depth. Or more.
8. Improved connectivity.
9. Some announced progress towards a semiconductor-based quantum computer by Intel.
10. Some announcement of progress towards a photonic quantum computer by Xanadu.
11. Some minimal progress on photonic quantum computing in general, Xanadu or others.
12. Somebody announces a credible roadmap for getting to 256 or “several hundred” qubits within five years. The Russians actually said something about 2024, but I’m not holding my breath for them.
13. Somebody other than Rigetti announcing near-term plans (within two years) to reach 92 to 128 qubits.
14. A couple more quantum computer vendors pop up and announce systems, even if they may not be able to fully demonstrate them over the next year. Europe? Japan? Korea? Australia?
15. Higher performance quantum simulators running on classical computers, with much more comprehensive debugging capabilities. The goal is that most algorithm developers can probably do most of their development work on a simulator, at least below 40 qubits. Configurable to be either unlimited — to develop long-term algorithms to run on future hardware — or to exactly match the limitations of existing NISQ hardware to more accurately reflect production applications on NISQ devices.
16. More interactive quantum simulators. There are a few, but this should become the norm.
17. A few published papers for results using more than 20 qubits. Even if only on a simulator — ideally both simulated and real.
18. At least one published paper for quantum phase estimation or quantum Fourier transform for at least 8 qubits of input data and at least 8 bits of result precision. Preferably on a real machine, but simulated at a minimum. Will we have to wait for full quantum error correction (QEC), or will incremental qubit advances get us within reach much sooner, possibly even current trapped-ion machines?
19. At least one published paper on simulating the quantum chemistry of a molecule more complex than water and nitrogen. Something requiring more than 20 qubits and more than 150 gates.
20. Public announcement of at least one if not two new potential technologies for qubits.
21. Public announcement of demonstrations of at least one if not two new potential technologies for qubits.
22. A number of smallish government research grants, like $5 million each. For algorithm research and tools as well as qubit technology. Including improved simulators.
23. At least one or two large government research grants of $10 million, if not $25 million or more. Particularly for much more ambitious hardware projects. Maybe a multi-processor system, such as four 64-qubit processors.
24. A clear and significant bump in federal-funding for all things quantum. Including NIST and DOE (the national laboratories.)
25. Similar national and regional R&D funding bumps for other regions of the globe. Certainly in Europe/EU. Japan, Korea, Australia, and China as well. India? Russia?
26. Some significant progress on the NSF-funded STAQ project (Software-Tailored Architecture for Quantum co-design) for a trapped-ion machine. Up their funding, if necessary — or redirect the program to exploit more recent commercial developments.
27. Many more GitHub repositories, with documentation, sample data, and sample results, for quantum programs, algorithms, and applications. Especially hybrid applications.
28. At least a little progress on identifying algorithmic building blocks that can be shared between applications.
29. Several free, online, high-quality books on quantum computing and algorithm design. Bootleg PDFs don’t count.
30. More free, online and high-quality lecture notes on quantum computing.

I sincerely expect many of those developments to occur in the coming year, but I’ll be quite satisfied if even half of those developments come to pass over the coming year.

Beyond that list, I would like to see at least several surprises, developments which I never even imagined as happening over the coming year.

Less-likely wish list

In addition, here’s a list of developments which I would like to see happen in 2020, but I’m not so hopeful, although I would like to see at least some progress towards them:

1. At least production-scale and production-quality quantum application, even if it is fairly minimal and doesn’t necessarily offer full quantum advantage.
2. At least one published paper for Shor’s algorithm to factor a semiprime larger than 15 and 21, like 6 or 7 bits, on a real quantum computer.
3. At least one published paper for Shor’s algorithm for 8–10 bit input number (semiprime), on a real quantum computer.
4. At least one published paper for quantum phase estimation or quantum Fourier transform for at least 16 qubits of input data and at least 10–16 bits of result precision. Preferably on a real quantum computer, but simulated as well. Will we have to wait for full quantum error correction (QEC), or will incremental qubit advances get us within reach much sooner, possibly even current trapped-ion machines?
5. Decent documentation — full, complete, and readable, with all relevant nuances — for a real quantum computer — system architecture, programming details (Principles Of Operation), and performance data. Documentation and specs for current offerings leave a lot to be desired.
6. A concise and fully documented set of introductory example quantum programs which actually do something practical on current quantum computers (NISQ) that people can relate to, as opposed to the current common examples of Deutsch, Deutsch-Jozsa, Simon, Grover, and Shor — which either do nothing practical or are impractical to implement on near-term machines. We need a really solid example of quantum parallelism; actually we need at least three or four, if not a lot more, since there is no one-size-fits-all approach to quantum parallelism. Again, simple, easy to understand examples that offer a template for developers to follow in application-specific algorithms.
7. A fully documented 4-bit quantum Fourier transform, showing all intermediate states, original state, final state, and measurement, for a variety of original states. Alternatively, a more sophisticated interactive quantum simulator which can visually show all of this information, but it should show the intermediate states labeled with the transform parameters (j, k, x[j], y[j], sum).
8. People start talking a lot about quantum algorithmic building blocks and even an initial few proposals for such building blocks. Both general-purpose building blocks and domain-specific building blocks.
9. A white paper which much more clearly explains exactly what a D-Wave machine is doing.
10. A white paper which clearly explains how to mimic the capabilities of a D-Wave machine on a gate-based quantum computer.
11. A white paper which clearly explains how one could decide between D-Wave and a gate-based quantum computer for a particular application, even if both are equally available.
12. Initiation of research on universal quantum computers — merging quantum and classical computing features in a single machine, with zero latency to transition between the two modes for hybrid algorithms.
13. Initiation of research on true quantum programming languages. And related programming models. The challenges of developing quantum algorithms.
14. More dramatic progress on photonic quantum computing. Something that at least sounds like it will give non-photonic qubits a run for their money within 2–3 years.

Other developments

Areas where I expect developments but personally won’t get as excited about:

1. Support software and tools. Necessary, but not my personal interest, except as particularly called out in the preceding lists.
2. Platform offerings from major cloud vendors.
3. A zillion consulting companies, of all sizes, jumping on the quantum bandwagon.
4. More books. Unfortunately, none are free and online.
5. More training courses.
6. More seminars.
7. More conferences.
8. Quantum bootcamps and hackathons become common.
9. Hype reaches unheard of levels.
10. Quantum awareness reaches the mainstream — but people will believe and be given the perception that much more is here now than is actually ready for use now to develop and deploy production-scale and production-quality applications.
11. Some rising concern (and rampant confusion!) about whether or not Shor’s algorithm might be able to break public key encryption sooner than previously expected.
12. Much larger-scale and glitzier marketing campaigns. Quantum advertising everywhere. Quantum computing in the Superbowl?! Ads on buses and trains?
13. Graphics designers go crazy with zany new ways to depict all things quantum.
14. A few juicy scandals — organizations claiming dramatic quantum advances, later found to be fraudulent.
15. A few controversial application projects — such as using quantum computing for extreme surveillance, nuclear weapons research, profiling criminals and terrorists, enabling and maintaining repressive and authoritarian regimes. [Could China use quantum algorithms to predict, anticipate, respond to, and suppress protests?!]

Follow-up

I expect to check in a couple of times over the coming year to see what progress is being made on the items on my wish lists. Maybe at mid-year and maybe quarterly. And almost certainly as the year draws to a close — and as I get ready to pen a fresh wish list for 2021.

And I may update these lists on occasion during the year, or at least for the first couple of months after initial publication as I stumble across items I missed initially.

For more of my writing: List of My Papers on Quantum Computing.