# News

- I am serving as PC chair for the 7th International Conference on Quantum Cryptography, QCRYPT'17. Submit your best quantum crypto papers! (Deadline: April 26th, 2017.)
- Watch an introductory talk presenting some of my research in quantum cryptography at the Caltech Computes conference in November 2016.
- I organize the CMS Theory seminar.
- I help organize TCS+, an online seminar series in theoretical computer science, accessible to the widest possible audience, and ensuring a carbon-free dissemination of ideas across the globe. See our website for more information.

# Research Interests

My research is centered around problems at the interface of theoretical computer science, quantum information and cryptography. I like to use complexity theory as a tool to study problems in quantum computing, and quantum mechanical phenomena as a way to gain a new perspective on classical concepts from theoretical computer science.

# Teaching

- Fall 2016: CS/Ph 120, Quantum Cryptography. Also offered as an EdX course!
- Spring 2016: CS 101, Introduction to modern cryptography.
- Winter 2016: CS/CMS 139, Advanced Algorithms.
- Spring 2015: CS/CMS 139, Advanced Algorithms.
- Fall 2014: CS286, Seminar in Computer Science. Topic: around the Quantum PCP conjecture.

# Recent papers

- Parallel DIQKD from parallel repetition
(Abstract)

Technical report arXiv:1703.08508.

- Rigorous renormalization group method for ground space and low-energy states of local Hamiltonians
(Abstract)

With Brenden Roberts, Olexei I. Motrunich.

Technical report arXiv:1703.01994.

- Overlapping Qubits
(Abstract)

With Rui Chao, Ben Reichardt, Chris Sutherland. Proceedings of ITCS'17.

Technical report arXiv:1701.01062.

- Focus on device independent quantum information
(Abstract)

With Stefano Pironio, Valerio Scarani. Closing editorial for New Journal of Physics special issue on device independence.

Journal link.

- Robust self-testing of many-qubit states
(Abstract)

With Anand Natarajan.

Technical report arXiv:1610.03574.

- QCMA hardness of ground space connectivity for commuting Hamiltonians
(Abstract)

With David Gosset, Jenish Mehta. Quantum 1, 16 (2017).

Technical report arXiv:1610.03582.

- Quantum Proofs
(Abstract)

With John Watrous. NOW Foundations and Trends in Theoretical Computer Science, Vol. 11, No. 1-2 (2015) 1-215 (journal link).

Technical report arXiv:1610.01664.

- Test for a large amount of entanglement, using few measurements
(Abstract)

With Rui Chao, Ben Reichardt, Chris Sutherland.

Technical report arXiv:1610.00771.

- Entanglement of approximate quantum strategies in XOR games
(Abstract)

With Dimiter Ostrev.

Technical report arXiv:1609.01652.

- Privacy Amplification Against Active Quantum Adversaries
(Abstract)

With Gil Cohen.

Technical report arXiv:1608.06318.

# Expository notes

- A simplified analysis (written in the format of a blog post) of my paper with Anand Natarajan presenting a robust test for n EPR pairs.
- A short proof of security for a protocol for device-independent quantum key distribution in parallel introduced by Jain, Miller and Shi.
- A simple proof of Renner's exponential de Finetti.
- An expository note, aimed at a general TCS audience, giving an analysis of the Blum-Lyby-Rubinfeld linearity test as a game with entangled provers.

# Recent talks

- Entanglement Tests from Group Representations, Workshop on Probabilistic and Algebraic Methods in Quantum Information Theory, Texas A&M University, 17 Jul 2017.
- Robust and/or efficient tests for high-dimensional entanglement, TYQI 2017, Paris, Paris, 19 Jun 2017.
- Rigorous RG algorithms and area laws for low energy eigenstates in 1D, IQC, Waterloo, Waterloo, 27 Mar 2017.
- Rigorous RG algorithms and area laws for low energy eigenstates in 1D, QIP'17, Seattle, 19 Jan 2017 (video).
- Overlapping Qubits, Theory Colloquium, UT Austin, 02 Dec 2016.
- Overlapping Qubits, Workshop on Subfactor Theory, Quantum Field Theory, and Quantum Information, Harvard University, Cambridge, 09 Oct 2016.
- Overlapping Qubits, QuPa seminar day, Institut Henri Poincare, Paris, 07 Jul 2016.
- Device independent quantum cryptography, MIT CIS seminar, MIT, 16 Mar 2016.
- Anchoring games for parallel repetition, UCSD theory seminar, UCSD, 08 Feb 2016.
- Interactive proofs for local Hamiltonians, Workshop on the Frontiers of Quantum Information and Computer Science, QUICS, University of Maryland, 01 Oct 2015 (video).
- A multiprover interactive proof system for the local Hamiltonian problem, Quantum Hamiltonian Complexity Reunion at the Simons Institute, Berkeley, 04 May 2015.
- Non-Signalling Parallel Repetition Via de Finetti Reductions, UCLA theory seminar, UCLA, 28 Apr 2015.
- Non-Signalling Parallel Repetition Via de Finetti Reductions, Simons Institute workshop on Information Theory in Complexity Theory and Combinatorics, Berkeley, 22 Apr 2015.
- Noncommutative Grothendieck inequalities and quantum two-player games, BMC Mini-Symposia on Quantum Information, Cambridge, UK, 01 Apr 2015.
- Quantum XOR Games, Banff workshop on Hypercontractivity and Log Sobolev Inequalities in Quantum Information Theory, Banff, 24 Feb 2015.

# Students

- Jenish Mehta
- Andrea Coladangelo
- Milan Cvitkovic

# Postdocs

- Piyush Srivastav (CMI postdoc 2014-2016), now at TIFR.
- Omar Fawzi (2016), now an assistant professor at ENS Lyon.
- Gil Cohen (CMI postdoc 2015-2016), now at Princeton.
- Stacey Jeffery (IQIM postdoc 2014-2016), now a senior researcher at CWI.

# Service

- Managing Editor for Theory of Computing.
- Editor for Quantum.
- Member of the Steering Committee of the ITCS (Innovations in Theoretical Computer Science) series of conferences.
- Program Committee member for QIP 2012, QCRYPT 2012, FSTTCS 2013, QIP 2014, STOC 2014, RANDOM 2014, QCRYPT 2014, ITCS 2015, TQC 2015, ITCS 2016, QIP 2016, CCC 2016, FOCS 2016, ICALP'17, QCRYPT'17
**(chair)**, STOC'18. - Refereed for journals SICOMP, JACM, TOC, Nature, Complexity, QIC, PRL, PRA, PRX and conferences STOC, FOCS, ITCS, CCC, APPROX/RANDOM, Crypto, QIP.

# Workshop organization

- I organized the 2016 SoCal theory day at Caltech, on November 11th 2016.
- In October 2015, together with Artur Ekert, Renato Renner, Miklos Santha and Umesh Vazirani I organized a small workshop on foundations of randomness at the Stellenbosch Institute for Advanced Study (STIAS) in South Africa. See the webpage or this blog post and follow-up posts (first talk, day 1, day 2, day 3) for information on the workshop.
- In February 2014 I co-organized (with Dorit Aharonov and John Watrous) a one-week workshop on Quantum Games and Protocols at the Simons Institute in Berkeley. This was the first out of three workshops in the special semester on Quantum Hamiltonian Complexity at the institute. See the Simons website for videos of all talks, this blog post for a summary of the workshop, this one describing a (personal) scientific outcome of the workshop.

# Funding

- NSF CAREER "Interactions with Untrusted Quantum Devices", 02/2016-01/2021.
- Air Force Young Investigator Award "Towards a Secure Quantum Network", 2016-2019.
- Okawa Foundation Research Grant 2015-2016.