W. J. Zeng

I believe that paradise and reality are kinds of libraries. You can view a selection of my library as well as some collected quotes. They're background reading for many of the important questions and themes in my intellectual life.

Previously, I ran a quantum and advanced computing group at goldman sachs. Before that I was at rigetti quantum computing, where I was product lead for building and launching rigetti's quantum cloud service on top of its superconducting QPUs and for the forest quantum programming toolkit, including the open source libraries pyquil and grove. I helped develop the quantum instruction set called quil. My phd thesis at oxford applies abstract methods (mainly from categorical algebra) to the study of quantum algorithms and protocols. Before that I worked with superconducting qubit systems at yale and eth zurich.

....................................
2024.09.04 - Towards violations of Local Friendliness with quantum computers [arXiv]

We introduce an experimental program to demonstrate increasingly significant Local Friendliness violations, proposing that branch factor be used to quantify how much a system is like an observer. Then we use ion trap and superconducting quantum computers to show proof-of-concept violations at the largest branch factors yet.

....................................
2024.07.09 - The AI Boom is good for Quantum Tech [blogpost]

....................................
2024.05.24 - Quantum amplitude estimation from classical signal processing [arXiv]

Through a connection to classical signal processing, we introduce a new amplitude estimation algorithm that beats state of the art performance.

....................................
2024.04.15 - Quantum Risk Analysis of Financial Derivatives [arXiv]

....................................
2024.03.11 - Unitary Fund 2023 Annual Report [blogpost] [pdf]

....................................
2024.01.09 - Assessing the Benefits and Risks of Quantum Computers [arXiv]

We conclude there is a credible expectation that quantum computers will be capable of performing computations which are economically-impactful before they will be capable of performing ones which are cryptographically-relevant.

....................................
2023.09.29 - Open Hardware in Quantum Technology [arXiv]

....................................
2023.09.04 - Local friendliness violations: experimental metaphysics and the nature of the observer @Math Models of Consciousness 2023 [video] #talk

....................................
2023.07.26 - Derivative Pricing using Quantum Signal Processing [arXiv]

....................................
2023.07.20 - Infinite Loops Podcast: Towards a Quantum Future (EP.171) [youtube] [podcast]

Covers quantum computing, encryption and risk, agency and objective reality, technology and magic, and more...

....................................
2023.06.28 - Increasing the Measured Effective Quantum Volume with Zero Noise Extrapolation [arXiv]

....................................
2023.04.28 - Zero noise extrapolation on logical qubits by scaling the error correction code distance [arXiv]

....................................
2023.04.28 - Exact and approximate simulation of large quantum circuits on a single GPU [arXiv]

....................................
2023.03.20 - Unitary Fund 2022 Annual Report [blogpost] [pdf]

....................................
2022.11.22 - End-to-end resource analysis for quantum interior point methods and portfolio optimization [arXiv]

....................................
2022.11.11 - Hardware optimized parity check gates for superconducting surface codes [arXiv]

....................................
2022.10.21 - A Q# Implementation of a Quantum Lookup Table for Quantum Arithmetic Functions [arXiv]

....................................
2022.10.16 - Automated quantum error mitigation based on probabilistic error reduction [arXiv]

....................................
2022.10.13 - Testing platform-independent quantum error mitigation on noisy quantum computers [arXiv]

....................................
2022.10.04 - We should run Wigner's Friend experiments [blogpost]

This blog post is about whether free choice and objective reality can coexist - not philosophically, but empirically - and how the tools of quantum computing could help us figure it out.

....................................
2022.09.15 - Using Q# to estimate resources needed for quantum advantage in derivative pricing [blogpost]

....................................
2022.06.25 - Unitary Fund experiments in public goods funding in quantum technologies @Funding the Commons 2022 [video] #talk

A talk on (1) why quantum technologies are a good place to experiment with public goods funding (2) our work at Unitary Fund and (3) thoughts on Science as a decentralized autonomous organization.

....................................
2022.06.07 - Quantum Resources Required to Block-Encode a Matrix of Classical Data [arXiv] [blogpost]

....................................
2022.03.10 - Error mitigation increases the effective quantum volume of quantum computers [arXiv]

....................................
2022.02.11 - Unitary Fund 2021 Annual Report [blogpost] [pdf]

....................................
2022.01.27 - Reducing the impact of time-correlated noise on zero-noise extrapolation [arXiv]

....................................
2021.12.09 - Progress towards quantum advantage in finance: Greeks and amplitude estimation Talk @Q2B 2021 [video]

....................................
2021.11.24 - Towards Quantum Advantage in Financial Market Risk using Quantum Gradient Algorithms [Quantum] [arXiv]

....................................
2021.08.12 - Low depth amplitude estimation on a trapped ion quantum computer [journal] [arXiv] [press release]

We implement our low-depth amplitude estimation algorithms on IonQ's trapped ion quantum computer. The QPU has sufficient performance to show improved sampling with increased circuit depth (to a point). This is not an "in practice" advantage because it is (1) on a toy problem and (2) the clock rate of the QPU is much slower than a classical comparison. That said it shows a benchmark that can be run on an ongoing basis to test quantum computing performance on amplitude estimation.

....................................
2021.08.04 - Extending quantum probabilistic error cancellation by noise scaling [journal] [arXiv]

We unify two error mitigating techniques, using noise scaling to make probabilistic error cancellation more robust against mis-calibrated noise models.

....................................
2021.02.18 - Faster Quantum Derivative Pricing with Variational Compilation @QHACK 2021 [video] #talk

....................................
2021.01.21 - Quantum computing in finance interview with Tearsheet [podcast]

....................................
2021.01.18 - Unitary Fund 2020 Annual Report [blogpost] [pdf]

....................................
2020.12.10 - Quantum Research at Goldman Sachs Talk @Q2B 2020 [video]

....................................
2020.12.07 - A Threshold for Quantum Advantage in Derivative Pricing [arXiv] [Quantum] [summary blogpost]

We give an upper bound on the resources required for valuable quantum advantage in pricing derivatives. We do this using novel methods that are the first viable path to end to end advantage for this application. We find that benchmark use cases require 8k logical qubits and a T-depth of 54 million and thus estimate that quantum advantage would require a logical clock speed of 50Mhz.

....................................
2020.12.06 - Low depth algorithms for quantum amplitude estimation [Quantum] [arXiv] [summary press release]

We design and analyze two new low depth algorithms for amplitude estimation (AE) achieving an optimal tradeoff between the quantum speedup and circuit depth. This gives options for running AE for quantum advantage in much noisier settings than before

....................................
2020.10.12 - Four strategies for the early quantum jungle. Keynote @QCE2020 Quantum Software Workshop [video] [slides]

....................................
2020.10.03 - Unitary Fund Q3 2020 Update [blog]

....................................
2020.09.09 - Mitiq: A software package for error mitigation on noisy quantum computers [arXiv]

....................................
2020.07.07 - Unitary Fund Q2 2020 Update [blog]

....................................
2020.05.21 - Digital zero noise extrapolation for quantum error mitigation [arXiv] [slides]

....................................
2020.04.02 - Unitary Fund Q1 2020 Update [blog]

....................................
2019.11.21 - Unitary Fund Launches New Micro-Grant Program & Research Collaboration [Medium]

....................................
2019.11.11 - Unpacking the Quantum Supremacy Benchmark with Python [Medium] [github]

....................................
2019.04.02 - Stanford CS269Q : Quantum Computer Programming [course page] [syllabus + lecture notes]

....................................
2019.01.31 - Clarifying Quantum Supremacy: better terms for milestones in quantum computation [Medium]

....................................
2018.10.16 - Unitary Fund: The first quarter [Medium] [unitary.fund]

....................................
2018.06.24 - Introducing the Unitary Fund: Get $2,000 for your open source quantum computing project [Medium] [unitary.fund] [coverage]

....................................
2018.05.09 - Programming the world's first quantum computers using Forest @ Skillsmatter, London [video]

An introduction to modern quantum programming. It covers why you might want to program a quantum computer and how you would do so today. The only background assumed is linear algebra and complex numbers at the level of undergraduate computer science.

....................................
2018.04.19 - The Arrival of Quantum Computing @ Impact.Tech [slides]

An introduction to quantum computing. Part 1 introduces the technology and Part 2 introduces the industry. It covers how you may get involved as a scientist, programmer, entrepreneur, or investor.

....................................
2018.02.22 - Forest 1.3: Upgraded developer tools, improved stability, and faster execution [blog]

....................................
2018.01.14 - Easy, Hybrid Quantum Programming with Forest @ QIP2018, Delft, Netherlands [video] #talk

....................................
2017.12.18 - Unsupervised Machine Learning on Rigetti 19Q with Forest 1.2 [blog] [arXiv]

....................................
2017.09.13 - Nature Comment: First Quantum Computers Need Smart Software [Nature] [podcast]

....................................
2017.08.24 - Rigetti Partners with CDL to Drive Quantum Machine Learning [blog]

....................................
2017.06.20 - Demonstration of Universal Parametric Entangling Gates on a Multi-Qubit Lattice [arXiv]

....................................
2017.06.20 - Parametrically-Activated Entangling Gates Using Transmon Qubits [arXiv]

....................................
2017.05.22 - Architectures for Hybrid Quantum/Classical Computing @ ORNL, TN [slides] #talk

....................................
2017.01.16 - A Practical Quantum Programming Workshop @ QIP2017, Seattle, WA [video] #talk

This was the original QIP workshop that introduced Forest, an open source quantum programming toolkit targeting near-term applications and devices. It is based on the Quil instruction set and introduces the libraries pyQuil and grove.

....................................
2016.11.29 - Quantum Programming on Near-term Devices @ Invited talk at the Semantics, Formal Reasoning, and Tools for Quantum Programming [slides] #talk

....................................
2016.10.17 - A Functional Architecture for Scalable Quantum Computing [IEEE] [direct download]

....................................
2016.08.11 - A Practical Quantum Instruction Set Architecture [arXiv] [blog]

....................................
2016.08.04 - Quantum Algorithms for Compositional Natural Language Processing [EPTCS]

....................................
2015.12.26 - The Abstract Structure of Quantum Algorithms [Oxford Thesis]

Quantum information brings together theories of physics and computer science. This synthesis challenges the basic intuitions of both fields. In this thesis, we show that adopting a unified and general language for process theories advances foundations and practical applications of quantum information. Results include new blackbox quantum algorithms, generalized quantum secret sharing and contextuality protocols, a categorical analysis of the Fourier transform in process theories, and an algorithm for natural language processing with a quantum computer. The main mathematical tools used in this thesis are group theory (esp. Fourier theory on finite groups), monoidal category theory, and categorical algebra.

....................................
2015.11.23 - Contextuality and the Weak Axiom in the Theory of Choice [Proc. Quantum Inter.]

....................................
2015.11.19 - The Quantum Software Challenge [Medium]

....................................
2015.06.09 - Diagrammatic Methods for the Specifcation and Verifcation of Quantum Algorithms @ IQC, UWaterloo - Quantum Programming and Circuits Workshop [slides] #talk

....................................
2015.02.07 - sticks [Medium] #fiction

....................................
2015.01.27 - see [Medium] #fiction

....................................
2014.06.06 - Abstract structure of unitary oracles for quantum algorithms @ QPL in Kyoto, Japan [slides] [video] [paper] #talk

....................................
2013.Spring - A Subtle Introduction to Category Theory [notes] #wip

....................................
2013.08.16 - For Sale [link] #fiction

....................................
Rowing

I've done my fair share of river batting.

The Oxford-Cambridge Boat Race 2012 [wiki]
Oxford Prepares Videos: [1] [2] [3] [4] [5] [6] [Epilogue] [Race Highlights]
Media: [NYT] [theguardian]

IRA National Championships 2011 w/ Yale Lightweight crew [video]

W. J. ZENG