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About me: I am a professor of Computer Science at Harvard University, and a member of the Harvard SEAS Theory of Computing group. Previously, I was a principal researcher at Microsoft Research New England, and before that I was an associate professor (with tenure) at Princeton University’s Computer Science department. I hold a Ph.D from the Weizmann Institute of Science, and was a postdoctoral fellow at the Institute for Advanced Study in Princeton. See also short biography and CV.

DUS: I am co director of undergraduate studies (DUS) of Computer Science at Harvard together with Prof. Stephen Chong. Please email cs-dus@seas.harvard.edu for any DUS related matters. For information about the Computer Science concentration at Harvard see the page csadvising.seas.harvard.edu. See also my contact information and office hours.

Current activities: Member of the editorial board of the Theory of Computing Journal (ToC) and the Electronic Colloquium of Computational Complexity. Member of the Committee for the Advancement of Theoretical Computer Science (CATCS). I am a memberof the scientific board of the Simons Institute for the Theory of Computing. I am a co organizer of the Harvard Machine Learning Theory seminar. Board member and co organizer of Addis Coder. See my CV for past activities.

Current students: Zhixian Lei, Yueqi Sheng, Chi-Ning Chou, Prayaag Venkat, Preetum Nakkiran (co-advised with Madhu Sudan), Beatrice Nash (co-advised with Misha Lukin).

Former students: Sharon Goldberg (co advised with Jennifer Rexford), David Xiao (co advised with Avi Wigderson), Mohammad Mahmoody, Moritz Hardt.

Former postdocs: Benny Applebaum, Thomas Holenstein, Guy Rothblum, Tselil Schramm.

Former interns: Moritz Hardt, Jonah Sherman, Yuan Zhou, Li-Yang Tan , Aaron Sidford, Aaron Potechin, Pravesh Kothari, Sam Hopkins.

Funding: I am currently supported by NSF awards CCF 1565264 and CNS 1618026, a Simons Investigator Fellowship and DARPA grant W911NF2010021. I am also grateful for support from Oracle Labs and past support by the NSF, as well as the Packard and Sloan foundations and the BSF.

See also my curriculum vitae and brief bio. I also occasionally blog and tweet.

Personal: I am married to Ravit Barak and father to Alma and Goren.

News

• I am teaching CS 229br: Advanced topics in the theory of Machine Learning in Fall 2020.

• Starting March 18th, I will be working remotely as part of Harvard’s (and the world’s) efforts to suppress COVID-19. See Harvard FAQ and specific information for CS undergraduates. All my office hours will be held remotely via zoom. The defaults are listed in this page but if it doesn’t work for you due to time zone differences please contact me.

• I am working on a new book on “Introduction to Theoretical Computer Science”. Comments are welcome as issues/pull requests on the GitHub repository

Selected Publications

All publications

Below are some of my papers, click here to see all my publications:

Writing

All Writing

I wrote a graduate textbook with Sanjeev Arora: Computational Complexity: A Modern Approach. I am currently writing an undergraduate textbook: Introduction to Theoretical Computer Science. I also wrote extensive notes on the sum of squares algorithm (with David Steurer). I occasionally blog on the Windows on Theory blog.

Some surveys and essays I wrote are below. See here for more of my less technical writing.

• Puzzles of modern machine learning - blog post.

• The different forms of quantum computing skepticsm - blog post. See also pdf version

• The Complexity of Public-Key Cryptography - survey/tutorial on the computational assumptions landscape of cryptogrpahy. Written in honor of Oded Goldreich’s 60th birthday.

• Bayesianism, frequentism, and the planted clique, or do algorithms believe in unicorns?, April 2016. See also blog post on windows of theory blog and video of a talk at Northwestern.

• Men in Computer Science - blog post, August 2017.

• Hopes, Fears, and Software Obfuscation, Communications of the ACM, March 2016. See also preprint version and video of short interview.

• Speaking about unspeakables, Harvard Lectures that Last 2016, February 2016, see also video of lecture.

• Structure vs Combinatorics in Computational Complexity, Windows on Theory blog, October 2013. See also adapted version in the bulletin of the European Association for Theoretical Computer Science.

• Truth vs. Proof - the Unique Games Conjecture and Feige’s Hypothesis, Windows on Theory blog, July 2012. See also adapted version in logic in computer science column of the bulletin of the European Association for Theoretical Computer Science.

• My first publication: tip for Ultima IV game in Commodore Magazine, June 1988.

Teaching

All teaching

Here are some of the courses / lectures I (Co) taught (see here for all courses):

• Harvard CS229br: Advanced topics in the theory of machine learning, Spring 2021

• Harvard CS127: Cryptography, Spring 2020, Spring 2018, Spring 2016.

• Harvard CS121: Introduction to Theoretical Computer Science - Fall 2019, Fall 2018, Fall 2017.

• Harvard CS229r: Physics and Computation Seminar, Fall 2018.

• Harvard CS229r / MIT 6.S898: Proofs, beliefs and algorithms through the lens of Sum of Squares - Fall 2016 - graduate course/seminar on the Sum of Squares algorithm.

• Addis Coder -summer course on algorithms and coding for high school students in Ethiopia.

• Princeton COS 522 - (graduate) Computational Complexity - Spring 2009

• Princeton COS 598D - Mathematical Methods in Theoretical Computer Science - Spring 2008

Contact

Office hours

	Email: . For Harvard related mails (apart from DUS), please use Any emails related to my role as DUS should be sent to cs-dus@seas.harvard.edu.
	Please use or for reference letter or manuscript review requests respectively. (emails to these addresses are forwarded to my main inbox, but are also tagged appropriately so I don't lose track of them. Emails to the reference address are also forwarded to my faculty coordinator.)
	Upcoming office hours (in Maxwell Dworkin 329): (see all hours and schedule appointments) dummy Loading...
	Physical Location: Office 329 (third floor) in Maxwell-Dworkin Hall, 33 Oxford Street, Cambrdige.
	Mailing Address: Professor Boaz Barak, Maxwell-Dworkin Hall Room 329, 33 Oxford Street, Cambridge, MA 02138.
	Administrative assistant: Evelyn (Evie) Santana-Nola, , santana@seas.harvard.edu
	Phone: (617) 496-1537 (I prefer email)