I work on research, product and strategy at
rigetti quantum
computing. I am focused on quantum computer architecture, quantum software
and algorithm engineering, and making quantum computing useful.

twitter 
linkedin 
arXiv 
currently listening 
unitary fund 
I am product lead for the
forest
experimental quantum programming toolkit, including the open source libraries
pyquil
and
grove.
I run the unitary fund to support open source
quantum programming with grants.
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.
If you want to learn more about how to get started with quantum computing, I've written a
short introduction, which is part of the
documentation for
pyQuil.
....................................
Introducing the Unitary Fund: Get $2,000 for your open source quantum computing project
[Medium]
[unitary.fund]
[coverage]
24 June, 2018
I'm starting a new experiment called the Unitary Fund:
accepting proposals now to get $2,000 for your open source quantum computing project.
....................................
Programming the world's first quantum computers using Forest
[video]
9 May, 2018 at Skillsmatter, London
This talk is 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.
....................................
The Arrival of Quantum Computing
[slides]
19 April, 2018 at Impact.Tech
This talk is 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.
....................................
Forest 1.3: Upgraded developer tools, improved stability, and faster execution
[blogpost]
22 February, 2017
In December, the team at Rigetti became the first to solve an unsupervised machine
learning problem on a gate model quantum computer. We did this by connecting one of
our recent superconducting quantum processors, a 19qubit system, to our software
platform, Forest. In the ten weeks since then, researchers have already used Forest
to train neural networks, program benchmarking games, and simulate nuclear physics.
Starting today, researchers using Forest will be upgraded to version 1.3, which
provides better tools for optimizing and debugging quantum programs. The upgrade
also provides greater stability in our quantum processor (QPU), which will let
researchers run more powerful quantum programs...
....................................
Easy, Hybrid Quantum Programming with Forest
[video]
#talk
14 January, 2018
QIP2018, Delft, Netherlands
The first scalable universal quantum computers are now available, such as the 19
qubit processor built by Rigetti Computing. As these devices mature, it is
important to consider how best to make use of them. This requires new and applied
programming models for quantum computing. In particular, promising nearterm
algorithms for quantum simulation, optimization, and machine learning require a
hybrid quantum/classical programming environment. In this talk, we introduce a
freely available opensource environment (Forest)
based on a sharedmemory intermediate representation
( Quil) that is optimized for
this hybrid model. The environment runs through a cloud API with clientside Python
libraries that target both superconducting quantum circuit and classical simulation
backends. We will share how to get started with Forest, as well as how to do
research with example hybrid algorithms using a quantum computer.
....................................
Unsupervised Machine Learning on Rigetti 19Q with Forest 1.2
[blogpost]
[arXiv
18 December, 2017
We are excited to share that our team has demonstrated unsupervised machine learning
using 19Q, our new 19qubit general purpose superconducting quantum processor. We did
this with a quantum/classical hybrid algorithm for clustering developed at Rigetti...
....................................
Nature Comment: First Quantum Computers Need Smart Software
[Nature] [podcast]
13 September, 2017
We outline three developments that are needed over the next five years to ensure
that the first quantum computers can be programmed to perform useful tasks. First,
developers must think in terms of 'hybrid' approaches that combine classical and
quantum processors. For example, at Rigetti we have developed an interface called
Quil, which includes a set of basic instructions for managing quantum gates and
classical processors and for reading and writing to and from shared memory. Second,
researchers and engineers must build and use opensource software for
quantum computing applications. Third, scientists need to establish a
quantum programming community to nurture an ecosystem of software. This community
must be interdisciplinary, inclusive and focused on applications.
....................................
Rigetti Partners with CDL to Drive Quantum Machine Learning
[blogpost]
24 August, 2017
....................................
Demonstration of Universal Parametric Entangling Gates on a MultiQubit Lattice
[arXiv]
20 June, 2017
Demonstration of entangling gates on the Rigetti 8Q processor. This was the first process ever made
available through Forest.
....................................
ParametricallyActivated Entangling Gates Using Transmon Qubits
[arXiv]
20 June, 2017
Parametric entangling gates developed for the Rigetti 8Q processor.
....................................
Architectures for Hybrid Quantum/Classical Computing
[slides]
#talk
22 May, 2017
Quantum Computing Institute Seminar, Oak Ridge National Lab, TN
In this talk, we introduce an
opensource environment (Forest) based on a
sharedmemory intermediate
representation (Quil).
The environment runs through a cloud API with clientside
Python libraries that can target both superconducting quantum circuit and classical
simulation backends. We discuss the programming model and implementations of
the
Quantum Approximate Optimization Algorithm in this environment.
....................................
A Practical Quantum Programming Workshop
[video]
#talk
16 January, 2017
QIP2017, Seattle, WA
This was the original QIP workshop that introduced
Forest,
an open source quantum programming toolkit targeting nearterm
applications and devices. It is based on the Quil instruction set and introduces the libraries
pyQuil and
grove.
....................................
Quantum Programming on Nearterm Devices
[slides]
#talk
29 November, 2016
Simons Institute, University of Berkeley, CA 
Invited talk at the Semantics, Formal Reasoning, and Tools for Quantum Programming
MURI Review.
....................................
A Functional Architecture for Scalable Quantum Computing
[IEEE]
[direct download]
17 October, 2016
We describe a scalable functional architecture for superconducting quantum computation, based on a
planar lattice of transmon and fluxonium qubits, parametric amplifiers, and a novel fast DC
controlled twoqubit gate.
....................................
A Practical Quantum Instruction Set Architecture
[arXiv]
[blogpost]
11 August, 2016
We introduce an abstract machine architecture for classical/quantum
computationsincluding compilationalong with a quantum instruction
language called Quil for explicitly writing these computations. With this formalism,
we discuss concrete implementations of the machine and nontrivial algorithms
targeting them. The introduction of this machine dovetails with ongoing development of
quantum computing technology, and makes possible portable descriptions of recent
classical/quantum algorithms.
This instruction set architecture is the basis for the quantum programming platform
Forest.
....................................
Quantum Algorithms for Compositional Natural Language Processing
[EPTCS]
4 August, 2016
We introduce an algorithm for compositional natural language processing that can be accelerated
quadratically by quantum computation.
....................................
Highthreshold decoding algorithms for the gauge color code
[slides]
#talk
16 March, 2016
Baltimore, MD 
APS March Meeting 2016
Gauge color codes are particularly interesting quantum error correcting codes because the admit a
universal logical gate set through gauge fixing. We study the threshold of gauge color codes using
Markovchain Monte Carlo decoding.
....................................
The Abstract Structure of Quantum Algorithms
[Oxford Thesis]
26 December, 2015
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.
....................................
Contextuality and the Weak Axiom in the Theory of Choice
[Proc. Quantum Inter.]
23 November, 2015
This work applies contextuality (a mathematical formalism developed in quantum mechanics)
to models of social choice theory. In essence, we mathematically characterize when it makes sense to
consider the choices of a group as composed of individual choices, finding an interesting link between
nosignaling theories and the weak axiom of revealed preference.
....................................
The Quantum Software Challenge
[Medium]
19 October, 2015
What software engineers should know about quantum computing...
....................................
Diagrammatic Methods for the Specifcation and Verifcation of Quantum Algorithms
[slides] #talk
9 June, 2015
Institute for Quantum Computing, University of Waterloo 
Quantum Programming and Circuits Workshop
....................................
sticks
[Medium] #fiction
7 Feburary, 2015
In earlier years, we would hold small angled sticks...
....................................
see
[Medium] #fiction
27 January, 2015
See that little in the weathered manâ€™s life could match the intensity, the panting rhythms,
the speed of the sled dogs...
....................................
Abstract structure of unitary oracles for quantum algorithms
[slides]
[video]
[paper]
#talk
6 June, 2014
Kyoto, Japan 
Quantum Physics and Logic (
QPL
) 2014
This paper studies the categorical structure of quantum algorithms with oracles to develop a new
algorithm for the deterministic identification of group homomorphisms into abelian groups. We also
discuss an application to the categorical theory of signalflow networks.
....................................
A Subtle Introduction to Category Theory
[notes]
Spring, 2013
Some playful notes and riffs on monoidal category theory. Very much a WIP.
....................................
For Sale
[link]
16 August, 2013
A microfiction.
....................................
Rowing
I've done my fair share of river batting.
The OxfordCambridge 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]
....................................
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