From rmhulett at stanford.edu Thu Nov 1 13:19:05 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Thu, 1 Nov 2018 20:19:05 +0000 Subject: [theory-seminar] Theory Lunch -- Andrew Stolman (UCSC) In-Reply-To: References: Message-ID: <2ae6d426-51ed-4e32-882e-a778ed447941@email.android.com> Someone left a glasses case in 463A, please claim! On Oct 30, 2018 1:28 PM, Reyna Marie Hulett wrote: Hi everybody, This week's theory lunch will be given by Andrew Stolman (UCSC) on ?Finding forbidden minors through random walks: an almost optimal one-sided tester for minor-closed properties?--see abstract below. As always, please join us Thursday from noon to 1 pm in Gates 463A! ---------------------------------------- Abstract: Let [G] be an undirected, bounded degree graph with vertices. Fix a finite graph [H] , and suppose one must remove edges from [G] to make it [H] -minor-free (for some small constant [\varepsilon > 0] ). We give an n1/2 + o(1)-time randomized algorithm that, with high probability, finds an [H] -minor in such a graph. As an application, suppose one must remove edges from a bounded degree graph [G] to make it planar. This result implies an algorithm, with the same running time, that produces a [K_{3,3}] or [K_5] minor in [G] . No prior sublinear time bound was known for this problem. By the graph minor theorem, we get an analogous result for any minor-closed property. Up to [n^{o(1)}] factors, this resolves a conjecture of Benjamini-Schramm-Shapira (STOC 2008) on the existence of one-sided property testers for minor-closed properties. Furthermore, our algorithm is nearly optimal, by an [\Omega(\sqrt{n})] lower bound of Czumaj et al (RSA 2014). This result appeared in FOCS 2018 and the paper can be found here https://arxiv.org/abs/1805.08187. Joint work with C. Seshadhri of UCSC and Akash Kumar of Purdue University. ---------------------------------------- Cheers, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 20181101_131751.jpg Type: image/jpeg Size: 1330517 bytes Desc: 20181101_131751.jpg URL: From rmhulett at stanford.edu Thu Nov 1 13:19:05 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Thu, 1 Nov 2018 20:19:05 +0000 Subject: [theory-seminar] Theory Lunch -- Andrew Stolman (UCSC) In-Reply-To: References: Message-ID: <2ae6d426-51ed-4e32-882e-a778ed447941@email.android.com> Someone left a glasses case in 463A, please claim! On Oct 30, 2018 1:28 PM, Reyna Marie Hulett wrote: Hi everybody, This week's theory lunch will be given by Andrew Stolman (UCSC) on ?Finding forbidden minors through random walks: an almost optimal one-sided tester for minor-closed properties?--see abstract below. As always, please join us Thursday from noon to 1 pm in Gates 463A! ---------------------------------------- Abstract: Let [G] be an undirected, bounded degree graph with vertices. Fix a finite graph [H] , and suppose one must remove edges from [G] to make it [H] -minor-free (for some small constant [\varepsilon > 0] ). We give an n1/2 + o(1)-time randomized algorithm that, with high probability, finds an [H] -minor in such a graph. As an application, suppose one must remove edges from a bounded degree graph [G] to make it planar. This result implies an algorithm, with the same running time, that produces a [K_{3,3}] or [K_5] minor in [G] . No prior sublinear time bound was known for this problem. By the graph minor theorem, we get an analogous result for any minor-closed property. Up to [n^{o(1)}] factors, this resolves a conjecture of Benjamini-Schramm-Shapira (STOC 2008) on the existence of one-sided property testers for minor-closed properties. Furthermore, our algorithm is nearly optimal, by an [\Omega(\sqrt{n})] lower bound of Czumaj et al (RSA 2014). This result appeared in FOCS 2018 and the paper can be found here https://arxiv.org/abs/1805.08187. Joint work with C. Seshadhri of UCSC and Akash Kumar of Purdue University. ---------------------------------------- Cheers, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: 20181101_131751.jpg Type: image/jpeg Size: 1330517 bytes Desc: 20181101_131751.jpg URL: From reingold at stanford.edu Thu Nov 1 14:58:46 2018 From: reingold at stanford.edu (Omer Reingold) Date: Thu, 1 Nov 2018 14:58:46 -0700 Subject: [theory-seminar] TOCA-SV in a week (Friday Nov. 9)! Message-ID: Dear Friends and Colleagues, Appended below is the schedule and abstracts for the TOCA-SV meeting next week that will be hosting Shafi Goldwasser for the Motwani colloquium. The event will take place on Friday November 9 at Huang Mackenzie center room 300. For direction and parking instructions please see https://tfsa.stanford.edu/pdfs/Parking_and_Directions.pdf. We are looking forward to seeing you all there! The organizing committee: Moses Charikar (Stanford), Ravi Kumar (Google), Omer Reingold (Stanford), D. Sivakumar (Google) and Gregory Valiant (Stanford) 11:00-11:45 Avishay Tal, Simons Institute & Stanford University, Oracle Separation of BQP and the Polynomial Hierarchy 11:45-12:30 Badih Ghazi, Google Resource-Efficient Common Randomness and Secret Key Generation 12:30-2:00 lunch 2:00-3:15 Motwani colloquium, Shafi Goldwasser, Simons Institute, UC Berkeley Pseudo Deterministic Algorithms and Proofs 3:15-5:30 Happy hour and student talks Abstracts: Avishay Tal, *Oracle Separation of BQP and the Polynomial Hierarchy* In their seminal paper, Bennett, Bernstein, Brassard and Vazirani [SICOMP, 1997] showed that relative to an oracle, quantum algorithms are unable to solve NP-complete problems in sub-exponential time (i.e., that Grover's search is optimal in this setting). In this work, we show a strong converse to their result. Namely, we show that, relative to an oracle, there exist computational tasks that can be solved efficiently by a quantum algorithm, but require exponential time for any algorithm in the polynomial hierarchy (a hierarchy of complexity classes that captures P, NP, coNP, and their generalizations). The tasks that exhibit this "quantum advantage" arise from a pseudo-randomness approach initiated by Aaronson [STOC, 2010]. Our core technical result is constructing a distribution over Boolean strings that "look random" to constant-depth circuits of quasi-polynomial size, but can be distinguished from the uniform distribution by very efficient quantum algorithms. Joint work with Ran Raz Badih Ghazi, *Resource-Efficient Common Randomness and Secret Key Generation* The task of manipulating randomness has been a subject of intense investigation in computational complexity with dispersers, extractors, pseudorandom generators, condensers, mergers being just a few of the objects of interest. All these tasks consider a single processor massaging random samples from an unknown source. In this talk, I will discuss a less studied setting where randomness is distributed among different players who would like to convert it to other forms in an efficient manner and with little communication. For instance players may be given access to a source of biased correlated bits and their goal may be to get a common random string out of this source. Even the setting where the source is known leads to some interesting questions that have been explored since the 70s with striking constructions and some surprisingly hard questions. After giving some background, I will describe recent work which explores the task of extracting common randomness from correlated sources with bounds on either the sample complexity or on the number of rounds of interaction. Based on joint works with T.S. Jayram, Mitali Bafna, Noah Golowich and Madhu Sudan Shafi Goldwasser, *Pseudo Deterministic Algorithms and Proofs* Probabilistic algorithms for both decision and search problems can offer significant complexity improvements over deterministic algorithms. One major difference, however, is that they may output different solutions for different choices of randomness. This makes correctness amplification impossible for search algorithms and is less than desirable in setting where uniqueness of output is important such as generation of system wide cryptographic parameters or distributed setting where different sources of randomness are used. Pseudo-deterministic algorithms are a class of randomized search algorithms, which output a unique answer with high probability. Intuitively, they are indistinguishable from deterministic algorithms by an polynomial time observer of their input/output behavior. In this talk I will describe what is known about pseudo-deterministic algorithms in the sequential, sub-linear and parallel setting. We will also describe n extension of pseudo-deterministic algorithms to interactive proofs for search problems where the veri fier is guaranteed with high probability to output the same output on different executions, regardless of the prover strategies. -------------- next part -------------- An HTML attachment was scrubbed... URL: From gvaliant at cs.stanford.edu Fri Nov 2 07:45:49 2018 From: gvaliant at cs.stanford.edu (Gregory Valiant) Date: Fri, 2 Nov 2018 07:45:49 -0700 Subject: [theory-seminar] post-deadline happy hour today @6pm! Message-ID: Hi Friends, We'll have our usual post-deadline happy hour, today at 6pm, in gates 463a. I probably won't have time to go to the store beforehand, so the material sustenance on offer might be a bit sparse, but we will have plenty of food for the mind and/or soul. (Though if we all bring whatever beer is hiding in our offices, I imagine we should be all set : ) Hope to see you this evening, -g -------------- next part -------------- An HTML attachment was scrubbed... URL: From ccanonne at cs.stanford.edu Fri Nov 2 07:50:47 2018 From: ccanonne at cs.stanford.edu (=?UTF-8?Q?Cl=c3=a9ment_Canonne?=) Date: Fri, 2 Nov 2018 07:50:47 -0700 Subject: [theory-seminar] post-deadline happy hour today @6pm! In-Reply-To: References: Message-ID: On 11/2/18 7:45 AM, Gregory Valiant wrote: > (Though if we all bring whatever beer is hiding in our offices, I > imagine we should be all set : ) I confirm :) Also, important note: having submitted, or attended to submit, a paper is *not* a prerequisite to attend the happy hour. Best, -- Cl?ment From ofirgeri at stanford.edu Fri Nov 2 13:12:46 2018 From: ofirgeri at stanford.edu (Ofir Geri) Date: Fri, 2 Nov 2018 20:12:46 +0000 Subject: [theory-seminar] Theory Seminar (11/2): Rotem Oshman In-Reply-To: References: Message-ID: Reminder: Rotem Oshman's talk is today at 3pm. Please note the non-standard location (Gates 392). ________________________________ From: Ofir Geri Sent: Wednesday, October 31, 2018 4:19:35 PM To: thseminar at cs.stanford.edu Subject: Theory Seminar (11/2): Rotem Oshman Hi all, This Friday in theory seminar, Rotem Oshman (Tel-Aviv University) will give a talk on Two Open Problems in Distributed Graph Algorithms (see abstract below). The talk will be at 3pm in Gates 392 - please note the unusual location! Hope to see you there! Ofir Two Open Problems in Distributed Graph Algorithms Speaker: Rotem Oshman (Tel-Aviv University) In a distributed graph algorithm, we have a network of computing nodes, where each node initially knows only its own local neighborhood; the nodes communicate over the network edges in order to solve some problem on the network graph. We are interested in algorithms that are fast, but also do not require a lot of communication between the network nodes. In this talk I will describe recent algorithms and lower bounds for two graph problems: exact maximum bipartite matching, and testing whether the network contains an even-length cycle of a specific length. Both problems do not have matching upper and lower bounds, so their complexity remains open. The talk will not assume any prior knowledge about distributed computing. -------------- next part -------------- An HTML attachment was scrubbed... URL: From moses at cs.stanford.edu Mon Nov 5 13:15:03 2018 From: moses at cs.stanford.edu (Moses Charikar) Date: Mon, 5 Nov 2018 13:15:03 -0800 Subject: [theory-seminar] Nima Anari at probability seminar today, 4pm Message-ID: Hi folks, Nima is speaking at the probability seminar today at 4pm on log-concave polynomials. Details below. Best, Moses Monday, November 5, 4pm: Probability Seminar, Sequoia Hall Room 200 Nima Anari, Stanford Computer Science Title: Log-Concave Polynomials: Counting and Sampling Matroid Bases and Beyond Abstract: I will discuss an analytic property of multivariate polynomials, which we call complete log-concavity. This property defines a large class of discrete distributions that should be thought of as the discrete analog of the well-studied continuous log-concave distributions. Examples satisfying this property include determinantal point processes and fractional powers of them, the random cluster model and Potts model for some regime of parameters, strongly Rayleigh distributions, uniform distributions over bases or independent sets of matroids, and other generalizations. Complete log-concavity is intimately connected to Hodge-Riemann relations of order one from Hodge theory, and also surprisingly high- dimensional expanders. The second connection allows us to efficiently sample from discrete distributions satisfying complete log-concavity. For many of the example distributions, this provides the first efficient sampling algorithm. In particular we obtain the first polynomial time algorithm to sample approximately uniformly from bases of an arbitrary matroid. This is joint work with Kuikui Liu, Shayan Oveis Gharan, and Cynthia Vinzant. -------------- next part -------------- An HTML attachment was scrubbed... URL: From rmhulett at stanford.edu Mon Nov 5 14:08:23 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Mon, 5 Nov 2018 22:08:23 +0000 Subject: [theory-seminar] Theory Lunch -- Mohammad Akbarpour Message-ID: Hi all, This week at theory lunch, Mohammad Akbarpour will present "Just a Few Seeds More: Value of Network Information for Diffusion"--see abstract below. As always, please join us Thursday from noon to 1 pm in Gates 463A! ---------------------------------------- Abstract: Identifying the optimal set of individuals to first receive information (?seeds?) in a social network is a widely-studied question in many settings, such as the diffusion of information, microfinance programs, and new technologies. Numerous studies have proposed various network-centrality based heuristics to choose seeds in a way that is likely to boost diffusion. Here we show that, for some frequently studied diffusion processes, randomly seeding s+x individuals can prompt a larger cascade than optimally targeting the best s individuals, for a small x. We prove our results for large classes of random networks, but also show that they hold in simulations over several real-world networks. This suggests that the returns to collecting and analyzing network information to identify the optimal seeds may not be economically significant. Given these findings, practitioners interested in communicating a message to a large number of people may wish to compare the cost of network-based targeting to that of slightly expanding initial outreach. Available at https://web.stanford.edu/~mohamwad/NetworkSeeding.pdf ---------------------------------------- Cheers, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: From rmhulett at stanford.edu Mon Nov 5 14:08:23 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Mon, 5 Nov 2018 22:08:23 +0000 Subject: [theory-seminar] Theory Lunch -- Mohammad Akbarpour Message-ID: Hi all, This week at theory lunch, Mohammad Akbarpour will present "Just a Few Seeds More: Value of Network Information for Diffusion"--see abstract below. As always, please join us Thursday from noon to 1 pm in Gates 463A! ---------------------------------------- Abstract: Identifying the optimal set of individuals to first receive information (?seeds?) in a social network is a widely-studied question in many settings, such as the diffusion of information, microfinance programs, and new technologies. Numerous studies have proposed various network-centrality based heuristics to choose seeds in a way that is likely to boost diffusion. Here we show that, for some frequently studied diffusion processes, randomly seeding s+x individuals can prompt a larger cascade than optimally targeting the best s individuals, for a small x. We prove our results for large classes of random networks, but also show that they hold in simulations over several real-world networks. This suggests that the returns to collecting and analyzing network information to identify the optimal seeds may not be economically significant. Given these findings, practitioners interested in communicating a message to a large number of people may wish to compare the cost of network-based targeting to that of slightly expanding initial outreach. Available at https://web.stanford.edu/~mohamwad/NetworkSeeding.pdf ---------------------------------------- Cheers, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: From moses at cs.stanford.edu Tue Nov 6 22:26:02 2018 From: moses at cs.stanford.edu (Moses Charikar) Date: Tue, 6 Nov 2018 22:26:02 -0800 Subject: [theory-seminar] Motwani CS Theory Colloquium: Shafi Goldwasser (Nov 9) Message-ID: The Motwani Distinguished Lectures are a series of theory colloquia aimed at a broad audience. The next lecture in the series will be given this Friday, Nov 9, by Shafi Goldwasser, Turing award winner and director of the Simons Institute at Berkeley, on Pseudo Deterministic Algorithms and Proofs (abstract below). You should definitely attend if you can! The talk is at 2pm on Nov 9 in the Mackenzie Room (Huang Engineering Center, Room 300). For direction and parking instructions please see https://tfsa.stanford.edu/pdfs/Parking_and_Directions.pdf. There will be a happy hour immediately following the talk. This Motwani Colloquium is part of TOCA-SV, our biannual gathering of CS theoreticians in academia and industry in the Silicon Valley area. See the full schedule here: https://sites.google.com/view/toca-sv-day-nov-2018/ Hope to see you there! Cheers, Moses Title: Pseudo Deterministic Algorithms and Proofs Shafi Goldwasser Abstract Probabilistic algorithms for both decision and search problems can offer significant complexity improvements over deterministic algorithms. One major difference, however, is that they may output different solutions for different choices of randomness. This makes correctness amplification impossible for search algorithms and is less than desirable in setting where uniqueness of output is important such as generation of system wide cryptographic parameters or distributed setting where different sources of randomness are used. Pseudo-deterministic algorithms are a class of randomized search algorithms, which output a unique answer with high probability. Intuitively, they are indistinguishable from deterministic algorithms by a polynomial time observer of their input/output behavior. In this talk I will describe what is known about pseudo-deterministic algorithms in the sequential, sub-linear and parallel setting. We will also describe an extension of pseudo-deterministic algorithms to interactive proofs for search problems where the verifier is guaranteed with high probability to output the same output on different executions, regardless of the prover strategies. -------------- next part -------------- An HTML attachment was scrubbed... URL: From ccanonne at cs.stanford.edu Wed Nov 7 17:01:56 2018 From: ccanonne at cs.stanford.edu (=?UTF-8?Q?Cl=c3=a9ment_Canonne?=) Date: Wed, 7 Nov 2018 17:01:56 -0800 Subject: [theory-seminar] TCS+ talk: Wednesday, November 14, Urmila Mahadev, UC Berkeley In-Reply-To: <7c7f1a3e-747b-9fc4-8317-9c5514ccf03a@cs.columbia.edu> References: <7c7f1a3e-747b-9fc4-8317-9c5514ccf03a@cs.columbia.edu> Message-ID: <27644919-b306-dcb3-a188-6b8ce203bf9c@cs.stanford.edu> Hi everyone, Next Wednesday morning, we'll have a TCS+ seminar at 10am, where Urmila Mahadev from UC Berkeley will (remotely) tell us about her recent work on "Classical Homomorphic Encryption for Quantum Circuits" (abstract below). As usual, this will be at *10am* in Gates 463; as usual we'll be able to ask questions during the talk, and as usual there will be pastries and light breakfast, from 9:55 until disappearance. See you then, -- Cl?ment ------------------------------- Speaker: Urmila Mahadev (UC Berkeley) Title: Classical Homomorphic Encryption for Quantum Circuits Abstract: We present the first leveled fully homomorphic encryption scheme for quantum circuits with classical keys. The scheme allows a classical client to blindly delegate a quantum computation to a quantum server: an honest server is able to run the computation while a malicious server is unable to learn any information about the computation. We show that it is possible to construct such a scheme directly from a quantum secure classical homomorphic encryption scheme with certain properties. Finally, we show that a classical homomorphic encryption scheme with the required properties can be constructed from the learning with errors problem. From tengyuma at stanford.edu Mon Nov 12 09:48:15 2018 From: tengyuma at stanford.edu (Tengyu Ma) Date: Mon, 12 Nov 2018 09:48:15 -0800 Subject: [theory-seminar] potentially interesting talk at stats seminar Message-ID: Hi theory folks, FYI, from the abstract, it sounds related to graph algorithms and algorithmic game theory; so I thought maybe somebody would be interested https://statistics.stanford.edu/sites/default/files/Nov13-2018.pdf Best, Tengyu -- Sent from my phone. Apologies for brevity. -------------- next part -------------- An HTML attachment was scrubbed... URL: From marykw at stanford.edu Mon Nov 12 14:50:16 2018 From: marykw at stanford.edu (Mary Wootters) Date: Mon, 12 Nov 2018 14:50:16 -0800 Subject: [theory-seminar] Fwd: Summer internship at Google research NYC In-Reply-To: References: Message-ID: Hi all, See below for an advertisement about summer internships at Google Research NY. --Mary ---------- Forwarded message --------- From: Srinadh Bhojanapalli Date: Mon, Nov 12, 2018 at 1:40 PM Subject: Summer internship at Google research NYC To: Hi Mary, I hope you are doing well. I have recently joined Google research in NYC. We have a summer internship program focused on algorithms and machine learning at Google research NY. The official call and the application procedure is given below. It will be great if you can circulate it among your students and other faculty. Thanks, -srinadh. Google Research NY: Internships for Summer 2019 A limited number of summer internship positions are available at Google Research, New York in the areas of machine learning, optimization, deep learning, computer vision and related fields. We seek motivated and enthusiastic colleagues with a solid research agenda and a demonstrated ability to generate new ideas and innovate. The candidates will have an opportunity to work closely with many researchers at Google, and have access to Google's unique computing infrastructure. The candidates will be expected to produce high-quality research and will be encouraged to publish in top conferences and journals in their areas of expertise. Applicants must - have strong theoretical and analytical foundations; - be enrolled in a Ph.D. program; - have good prototyping skills. The internship is planned for the summer of 2019. A minimum of 12 weeks is required. Applicants should send a curriculum vitae (including a list of publications) and contact information of two references who can comment on the applicant's research potential, one of whom should be the dissertation advisor, to *apply-research-internship-ny-2019 at google.com *. The application deadline is *December 14, 2018* but the selection process will start on first-come, first-served basis. -------------- next part -------------- An HTML attachment was scrubbed... URL: From tengyuma at stanford.edu Mon Nov 12 21:22:28 2018 From: tengyuma at stanford.edu (Tengyu Ma) Date: Mon, 12 Nov 2018 21:22:28 -0800 Subject: [theory-seminar] [cs-seminars] Theory Seminar: Andrew Chi-Chih Yao on Auction and Blockchain Message-ID: Hi everyone, We will have a special theory seminar by the Turing Award Laureate Prof. Andrew Chi-Chih Yao from Tsinghua University at 2PM-3PM this Friday, Nov 16th, in Gates 104. Hope to see you there! *Title:* Some Perspectives on FinTech *Speaker:* Andrew Chi-Chih Yao, Tsinghua University *Abstract:* FinTech can be seen as the meeting of minds between economics and computer science in the digital age. One of its major intellectual foundations is the interdisciplinary subject of multiparty computation, which involves reliable distributed computing and cryptography from the side of computer science, and efficient mechanism design for financial activities from the side of economics. In this talk we discuss some recent work in auction and blockchain from this perspective. For example, is it true that more revenue can always be extracted from an auction where the bidders are more willing to pay than otherwise? Can more revenue be extracted when the bidders are more risk-tolerant than otherwise? We also present some new results on blockchain fees. These results help shed light on some structural questions in economics whose answers are non-obvious. *Bio* (from Wiki Award section): Andrew Chi-Chih Yao is currently a Professor and the Dean of Institute for Interdisciplinary Information Sciences (IIIS) at Tsinghua University. In 1996 he was awarded the Knuth Prize. He received the Turing Award, the most prestigious award in computer science, in 2000, "in recognition of his fundamental contributions to the theory of computation, including the complexity-based theory of pseudorandom number generation, cryptography, and communication complexity". He is a member of U.S. National Academy of Sciences, a fellow of the American Academy of Arts and Sciences, a fellow of the American Association for the Advancement of Science, a fellow of the Association for Computing Machinery, and an academician of Chinese Academy of Sciences. -- Sent from my phone. Apologies for brevity. -------------- next part -------------- An HTML attachment was scrubbed... URL: From ofirgeri at stanford.edu Tue Nov 13 12:25:09 2018 From: ofirgeri at stanford.edu (Ofir Geri) Date: Tue, 13 Nov 2018 20:25:09 +0000 Subject: [theory-seminar] Theory Seminar (11/16): Jonathan Mosheiff Message-ID: Hi all, This Friday, Jonathan Mosheiff from Weizmann will give a theory seminar talk: On the weight distribution of random binary linear codes (abstract below). The talk will take place in Gates 392 at 3:15 PM (shortly after Andrew Chi-Chih Yao's talk). Please note the different locations for the two talks. Jonathan will be visiting both Thursday 11/15 and Friday 11/16, and will also be giving a (different) talk in the combinatorics seminar on 11/15. If you'd like to meet with him, please contact Mary at marykw at stanford.edu Hope to see you there! Ofir On the weight distribution of random binary linear codes Speaker: Jonathan Mosheiff (Weizmann) A random (binary) linear code is a dimension lambda*n (0 < \lambda < 1) linear subspace of the binary n-dimensional hypercube, chosen uniformly from among all such subspaces. Such codes play an important role in the theory of error correcting codes, since they achieve the best known rate vs. distance trade-off, i.e., the Gilbert-Varshamov lower bound. Under a random errors regime, the problem of decoding these codes is known as Learning Parity with Noise, and has many cryptographic applications. This work is motivated by the contrast between the importance of random linear codes and how little we know about them. Much of the interesting information about a code C is captured by its weight distribution. This is the vector (w_0,w_1,...,w_n) where w_i counts the elements of C with Hamming weight i. In this work we study the weight distribution of random linear codes. In our main result we compute the moments of the random variable w_(gamma*n), where 0 < \gamma < 1 is a fixed constant and n goes to infinity. This is joint work with Nati Linial. -------------- next part -------------- An HTML attachment was scrubbed... URL: From ccanonne at cs.stanford.edu Tue Nov 13 15:42:04 2018 From: ccanonne at cs.stanford.edu (=?UTF-8?Q?Cl=c3=a9ment_Canonne?=) Date: Tue, 13 Nov 2018 15:42:04 -0800 Subject: [theory-seminar] TCS+ talk: Wednesday, November 14, Urmila Mahadev, UC Berkeley In-Reply-To: <27644919-b306-dcb3-a188-6b8ce203bf9c@cs.stanford.edu> References: <7c7f1a3e-747b-9fc4-8317-9c5514ccf03a@cs.columbia.edu> <27644919-b306-dcb3-a188-6b8ce203bf9c@cs.stanford.edu> Message-ID: <0e1f8bd5-22ba-8c07-7e7f-afd781d8d0a5@cs.stanford.edu> Reminder: today is the 13th, so this is happening tomorrow morning! -- Cl?ment On 11/7/18 5:01 PM, Cl?ment Canonne wrote: > Hi everyone, > > Next Wednesday morning, we'll have a TCS+ seminar at 10am, where Urmila > Mahadev from UC Berkeley will (remotely) tell us about her recent work > on? "Classical Homomorphic Encryption for Quantum Circuits" (abstract > below). > > As usual, this will be at *10am* in Gates 463;? as usual we'll be able > to ask questions during the talk, and as usual there will be pastries > and light breakfast, from 9:55 until disappearance. > > See you then, > > -- Cl?ment > > ------------------------------- > Speaker: Urmila Mahadev (UC Berkeley) > Title: Classical Homomorphic Encryption for Quantum Circuits > > Abstract: We present the first leveled fully homomorphic encryption > scheme for quantum circuits with classical keys. The scheme allows a > classical client to blindly delegate a quantum computation to a quantum > server: an honest server is able to run the computation while a > malicious server is unable to learn any information about the > computation. We show that it is possible to construct such a scheme > directly from a quantum secure classical homomorphic encryption scheme > with certain properties. Finally, we show that a classical homomorphic > encryption scheme with the required properties can be constructed from > the learning with errors problem. > > _______________________________________________ > theory-seminar mailing list > theory-seminar at lists.stanford.edu > https://mailman.stanford.edu/mailman/listinfo/theory-seminar From rmhulett at stanford.edu Wed Nov 14 14:07:59 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Wed, 14 Nov 2018 22:07:59 +0000 Subject: [theory-seminar] Theory Lunch -- Yours Truly Message-ID: Hi folks, Tomorrow I'll be presenting some work with Ashish Goel and Anilesh Krishnaswamy entitled "Relating Metric Distortion and Fairness of Social Choice Rules." As always, please join us Thursday from noon to 1 pm in Gates 463A. Note that there is no lunch next week--have a great Thanksgiving! ---------------------------------------- Abstract: The study of voting theory has a long history. However, almost all of that history focused on qualitative, axiomatic ways to evaluate voting rules (e.g., the majority winner criterion, the Condorcet criterion). In contrast, a utilitarian distortion framework offers a quantitative way to evaluate such rules, even though voters submit only a preference ranking over candidates. In this model, we assume the voters have some unknown utility or cost for each candidate, which we can only observe via the preference rankings generated thereby. The distortion of a voting rule is the worst-case approximation ratio of the total social cost of the candidate chosen by that rule versus the optimal candidate (w.r.t. the cost profile). A fairness ratio can analogously be defined as the worst-case approximation ratio for an appropriate, strong measure of fairness (based on approximate majorization). In this work, we focus on the model where voters' costs for candidates correspond to distances in some arbitrary, unknown metric space. Surprisingly, this modest assumption allows us to obtain constant factor distortion and fairness ratio, e.g., using the Copeland rule. (By contrast, plurality only achieves distortion linear in the number of candidates.) We prove that the distinct notions of distortion and fairness ratio are in fact closely linked--within an additive factor of 2 for any voting rule. This implies new results for rules where only the distortion was previously known, and arguably strengthens the case for distortion as a way to evaluate voting rules. ---------------------------------------- Best, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: From rmhulett at stanford.edu Wed Nov 14 14:07:59 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Wed, 14 Nov 2018 22:07:59 +0000 Subject: [theory-seminar] Theory Lunch -- Yours Truly Message-ID: Hi folks, Tomorrow I'll be presenting some work with Ashish Goel and Anilesh Krishnaswamy entitled "Relating Metric Distortion and Fairness of Social Choice Rules." As always, please join us Thursday from noon to 1 pm in Gates 463A. Note that there is no lunch next week--have a great Thanksgiving! ---------------------------------------- Abstract: The study of voting theory has a long history. However, almost all of that history focused on qualitative, axiomatic ways to evaluate voting rules (e.g., the majority winner criterion, the Condorcet criterion). In contrast, a utilitarian distortion framework offers a quantitative way to evaluate such rules, even though voters submit only a preference ranking over candidates. In this model, we assume the voters have some unknown utility or cost for each candidate, which we can only observe via the preference rankings generated thereby. The distortion of a voting rule is the worst-case approximation ratio of the total social cost of the candidate chosen by that rule versus the optimal candidate (w.r.t. the cost profile). A fairness ratio can analogously be defined as the worst-case approximation ratio for an appropriate, strong measure of fairness (based on approximate majorization). In this work, we focus on the model where voters' costs for candidates correspond to distances in some arbitrary, unknown metric space. Surprisingly, this modest assumption allows us to obtain constant factor distortion and fairness ratio, e.g., using the Copeland rule. (By contrast, plurality only achieves distortion linear in the number of candidates.) We prove that the distinct notions of distortion and fairness ratio are in fact closely linked--within an additive factor of 2 for any voting rule. This implies new results for rules where only the distortion was previously known, and arguably strengthens the case for distortion as a way to evaluate voting rules. ---------------------------------------- Best, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: From ccanonne at cs.stanford.edu Wed Nov 14 14:52:56 2018 From: ccanonne at cs.stanford.edu (=?UTF-8?Q?Cl=c3=a9ment_Canonne?=) Date: Wed, 14 Nov 2018 14:52:56 -0800 Subject: [theory-seminar] Upcoming workshop at Simons: Sublinear Algorithms and Nearest-Neighbor Search Message-ID: <45bfc130-cef2-c111-d0bf-cd62554a7d47@cs.stanford.edu> Hi everyone, The week leading to the Theory Retreat, the Simons institute will be hosting a workshop on "Sublinear Algorithms and Nearest-Neighbor Search", which may be of interest to people here: https://simons.berkeley.edu/data-science-2018-3 It's free, though registration is recommended. The only drawback is that getting to Berkeley for 9am involves a certain amount of traffic. Best, -- -- Cl?ment From marykw at stanford.edu Thu Nov 15 17:54:29 2018 From: marykw at stanford.edu (Mary Wootters) Date: Thu, 15 Nov 2018 17:54:29 -0800 Subject: [theory-seminar] Course Announcement: EE387/CS250 (Algebraic Error Correcting Codes) Message-ID: Hi all, In the winter I will be teaching EE387/CS250, Algebraic Error Correcting Codes. The course meets Monday and Wednesday, 4:30-5:50pm. The official blurb is below, but the informal pitch for the course is as follows: This class is an introduction to algebraic error correcting codes (ECCs), with an emphasis on the diverse applications of ECCs. To define the terms in the title, an "error correcting code" is a tool to encode data to protect it from noise, and the adjective "algebraic" means that we will construct these codes mostly using tools from abstract algebra; the main workhorse is (variants of) polynomial interpolation over finite fields. (But don't worry if you're not an expert in abstract algebra! The class is self-contained and we will cover all the algebra that we need.) It turns out that these algebraic tools are extremely useful, and not just for the "standard" ECC applications of communication and storage. We'll also talk about applications in cryptography, algorithm design, group testing, compressed sensing, complexity theory and pseudorandomness. The goals of the course are to (a) introduce you to the basics of error correcting codes, and (b) to familiarize you with an algebraic toolkit that you can use in a variety of settings, not just for ECCs. The class will involve three problem sets and a final project. The project can be pretty much anything you want: in the past, some people have done original research, some have read and digested a few research papers, some have looked into real-life instances of error correcting codes, and some have implemented something. (I do have an "art project" option on the syllabus, but so far no one has taken me up on it...) If you are interested, please enroll! Best, Mary -------- Official blurb: *Course Description: *Introduction to the theory of error correcting codes, emphasizing algebraic constructions and diverse applications throughout computer science and engineering. Topics include basic bounds on error correcting codes; Reed-Solomon and Reed-Muller codes; list-decoding, list-recovery and locality. Applications may include communication, storage, complexity theory, pseudorandomness, cryptography, streaming algorithms, group testing, and compressed sensing. *Prerequisites:* Linear algebra, basic probability (at the level of, say, CS109, CME106 or EE178) and "mathematical maturity" (students will be asked to write proofs). Familiarity with finite fields will be helpful but not required. -------------- next part -------------- An HTML attachment was scrubbed... URL: From ofirgeri at stanford.edu Fri Nov 16 12:08:49 2018 From: ofirgeri at stanford.edu (Ofir Geri) Date: Fri, 16 Nov 2018 20:08:49 +0000 Subject: [theory-seminar] Theory Seminar (11/16): Jonathan Mosheiff In-Reply-To: References: Message-ID: Reminder: Two theory seminars today - Andrew Chi-Chih Yao at 2pm in Gates 104 and Jonathan Mosheiff at 3:15pm in Gates 392. Please also note that there is no theory lunch or theory seminar next week (Thanksgiving week). ________________________________ From: Ofir Geri Sent: Tuesday, November 13, 2018 12:25:09 PM To: thseminar at cs.stanford.edu Subject: Theory Seminar (11/16): Jonathan Mosheiff Hi all, This Friday, Jonathan Mosheiff from Weizmann will give a theory seminar talk: On the weight distribution of random binary linear codes (abstract below). The talk will take place in Gates 392 at 3:15 PM (shortly after Andrew Chi-Chih Yao's talk). Please note the different locations for the two talks. Jonathan will be visiting both Thursday 11/15 and Friday 11/16, and will also be giving a (different) talk in the combinatorics seminar on 11/15. If you'd like to meet with him, please contact Mary at marykw at stanford.edu Hope to see you there! Ofir On the weight distribution of random binary linear codes Speaker: Jonathan Mosheiff (Weizmann) A random (binary) linear code is a dimension lambda*n (0 < \lambda < 1) linear subspace of the binary n-dimensional hypercube, chosen uniformly from among all such subspaces. Such codes play an important role in the theory of error correcting codes, since they achieve the best known rate vs. distance trade-off, i.e., the Gilbert-Varshamov lower bound. Under a random errors regime, the problem of decoding these codes is known as Learning Parity with Noise, and has many cryptographic applications. This work is motivated by the contrast between the importance of random linear codes and how little we know about them. Much of the interesting information about a code C is captured by its weight distribution. This is the vector (w_0,w_1,...,w_n) where w_i counts the elements of C with Hamming weight i. In this work we study the weight distribution of random linear codes. In our main result we compute the moments of the random variable w_(gamma*n), where 0 < \gamma < 1 is a fixed constant and n goes to infinity. This is joint work with Nati Linial. -------------- next part -------------- An HTML attachment was scrubbed... URL: From reingold at stanford.edu Mon Nov 19 09:56:44 2018 From: reingold at stanford.edu (Omer Reingold) Date: Mon, 19 Nov 2018 09:56:44 -0800 Subject: [theory-seminar] Fwd: PCP-fest, 18-20 In-Reply-To: References: Message-ID: A great lineup of speakers if you are in the area. ---------- Forwarded message --------- From: Dor Minzer Date: Mon, Nov 19, 2018, 8:03 AM Subject: PCP-fest, 18-20 To: Dear Omer, We're holding a PCP centered workshop in Tel-Aviv. Could you please forward the announcement below to the relevant lists in Stanford? Thanks, Dor ___________________________________ We hereby invite you to the upcoming PCP-fest, to be held on December 18-20, 2018 in Tel-Aviv University, Israel. The workshop will focus on the state of the art theoretical results on PCPs, as well as recent applications, in particular, with regards to Blockchain technology. More information about the workshop can be found in the website . Registration is mandatory (but free). We would be able to provide limited travel support for participants; to apply, please indicate it in the registration form. Looking forward to see you, The organizers. -------------- next part -------------- An HTML attachment was scrubbed... URL: From ofirgeri at stanford.edu Sun Nov 25 23:24:46 2018 From: ofirgeri at stanford.edu (Ofir Geri) Date: Mon, 26 Nov 2018 07:24:46 +0000 Subject: [theory-seminar] Theory Seminar (11/28): Urmila Mahadev Message-ID: Hi all, This Wednesday, Urmila Mahadev (UC Berkeley) will be giving a theory seminar talk on Classical Verification of Quantum Computations (abstract below). The talk will be at 3:00 PM in Gates 463A. Please note that this week's talk is on Wednesday (and there will be no theory seminar on Friday). Hope to see you there! Ofir Classical Verification of Quantum Computations Speaker: Urmila Mahadev (UC Berkeley) We present the first protocol allowing a classical computer to interactively verify the result of an efficient quantum computation. We achieve this by constructing a measurement protocol, which allows a classical string to serve as a commitment to a quantum state. The protocol forces the prover to behave as follows: the prover must construct an n qubit state of his choice, non-adaptively measure each qubit in the Hadamard or standard basis as directed by the verifier, and report the measurement results to the verifier. The soundness of this protocol is enforced based on the assumption that the learning with errors problem is computationally intractable for efficient quantum machines. -------------- next part -------------- An HTML attachment was scrubbed... URL: From rmhulett at stanford.edu Tue Nov 27 12:59:35 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Tue, 27 Nov 2018 20:59:35 +0000 Subject: [theory-seminar] Theory Lunch -- Dima Kogan Message-ID: Hi folks, In our penultimate theory lunch of the quarter, Dima Kogan will present "From Cryptanalysis to Communication Complexity"--see abstract below. As always, please join us Thursday from noon to 1 pm in Gates 463A! ---------------------------------------- Abstract: The first problem we will discuss comes from cryptanalysis. In the permutation-inversion problem, first studied by Hellman (1980), an algorithm gets black-box access to a permutation $\pi:[N] \to [N]$ and takes as input a point $y \in [N]$, along with some auxiliary information about $\pi$. The algorithm must output $\pi^{-1}(y)$. The second problem we will discuss comes from communication complexity. There, a major goal is to prove a super-logarithmic lower bound for some problem for a super-poly-logarithmic number of players in the number-on-the-forehead model. A classic candidate for such a lower bound is the pointer jumping problem, in which the goal of the players is to follow a sequence of pointers in a layered directed graph, where each player has one of the layers written on her forehead. Although these two problems seem to have little in common, we will show that using classic cryptanalytic algorithms for permutation inversion we get new upper bounds for multiparty pointer jumping, improving the previous best bound of Pudl?k, R?dl, and Sgall (1997). As far as we know, this is the first application of a cryptanalytic algorithm to a communication-complexity problem. Joint work with Henry Corrigan-Gibbs. ---------------------------------------- Best, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: From rmhulett at stanford.edu Tue Nov 27 12:59:35 2018 From: rmhulett at stanford.edu (Reyna Marie Hulett) Date: Tue, 27 Nov 2018 20:59:35 +0000 Subject: [theory-seminar] Theory Lunch -- Dima Kogan Message-ID: Hi folks, In our penultimate theory lunch of the quarter, Dima Kogan will present "From Cryptanalysis to Communication Complexity"--see abstract below. As always, please join us Thursday from noon to 1 pm in Gates 463A! ---------------------------------------- Abstract: The first problem we will discuss comes from cryptanalysis. In the permutation-inversion problem, first studied by Hellman (1980), an algorithm gets black-box access to a permutation $\pi:[N] \to [N]$ and takes as input a point $y \in [N]$, along with some auxiliary information about $\pi$. The algorithm must output $\pi^{-1}(y)$. The second problem we will discuss comes from communication complexity. There, a major goal is to prove a super-logarithmic lower bound for some problem for a super-poly-logarithmic number of players in the number-on-the-forehead model. A classic candidate for such a lower bound is the pointer jumping problem, in which the goal of the players is to follow a sequence of pointers in a layered directed graph, where each player has one of the layers written on her forehead. Although these two problems seem to have little in common, we will show that using classic cryptanalytic algorithms for permutation inversion we get new upper bounds for multiparty pointer jumping, improving the previous best bound of Pudl?k, R?dl, and Sgall (1997). As far as we know, this is the first application of a cryptanalytic algorithm to a communication-complexity problem. Joint work with Henry Corrigan-Gibbs. ---------------------------------------- Best, -Reyna -------------- next part -------------- An HTML attachment was scrubbed... URL: From reingold at stanford.edu Tue Nov 27 15:01:21 2018 From: reingold at stanford.edu (Omer Reingold) Date: Tue, 27 Nov 2018 15:01:21 -0800 Subject: [theory-seminar] Fwd: Sexual harassment In-Reply-To: References: Message-ID: Hello everyone, I am forwarding the email below, regarding the conduct of Yuval Peres, partly as a fair public warning to our community. Another reason is to emphasize again that sexual harassment and sexual misconduct go beyond the narrow definitions of past generations, and for a good reason. As we and others discussed repeatedly, sexual misconduct harms individual and hurts the community (and thus hurts science as well). We can argue about the specific rules to apply but the bottom line is that we should all be able to share in the immense intellectual excitement that is TOC and the closeness between collaborators that it brings without this intellectual passion and closeness be misconstrued as anything else (in the spirit of this rather old post ). Finally, I want to remind everyone (and especially students), that you need not be alone if you have been hurt (on campus, in a conference or elsewhere as part of your work and even independent of work). All of the theory faculty are here to support and there are multiple resources in CS and on campus. Just contact whoever you feel most comfortable with. Best wishes, Omer ---------- Forwarded message --------- From: Ehud Friedgut Date: Tue, Nov 27, 2018 at 5:07 AM Subject: Sexual harassment To: ofer zeitouni , Itai Benjamini < itai.benjamini at gmail.com>, Ronen Eldan , David Peleg < david.peleg at weizmann.ac.il>, Michal Irani , Robert Krauthgamer , Jennifer Chayes < jchayes at microsoft.com>, Christian Borgs , Anna Karlin , Ronitt Rubinfeld < ronitt at csail.mit.edu>, Noga Alon , Benjamin Sudakov < benny.sudakov at gmail.com>, Michael Krivelevich , Asaf Shapira , Michal Karonski , Andrzej Rucinski , Wojtek Samotij < wojteksa at gmail.com>, Ron Peled , James R. Lee < jrl at cs.washington.edu>, Nati Linial , Avi Wigderson < avi at ias.edu>, Gil Kalai , Penny Haxell < pehaxell at math.uwaterloo.ca>, Tamar Ziegler , Dorit Aharonov , , < aaronson at cs.utexas.edu>, , , < irani at ics.uci.edu>, , , , Cc: Irit Dinur , Oded Goldreich < oded.goldreich at weizmann.ac.il> Hello all, This is an email composed by Irit Dinur, Oded Goldreich and me. The purpose of this email is to share with you concerns that we had regarding the unethical behavior of Yuval Peres. The behavior we are referring to includes several recent incidents from the past few years, on top of the two ?big? cases of sexual harassment that led to severe sanctions against him by his employer, Microsoft, and to the termination of his connections with the University of Washington. Together with two colleagues who are highly regarded and trusted by us, we have first and second-hand testimonies (by people we trust without a shed of doubt) of at least five additional cases of him approaching junior female scientists, some of them students, with offers of intimate nature, behavior that has caused its victims quite a bit of distress since these offers were "insistent". While the examples that we encountered from the last few years do not fall under the category of sexual harassment from a legal point of view, they certainly caused great discomfort to the victims, who were young female scientists, putting them in a highly awkward situation, and creating an atmosphere that they'd rather avoid (i.e., they would rather miss a conference or a lecture than risk being subjected to repeated intimate offers by him). We wish to stress that his aggressive advances toward young women, usually with no previous friendly connections with him, puts them in a vulnerable position of fearing to cross a senior scientist who might have an impact on their career, which is at a fragile stage. We believe that the questions of whether or not Yuval Peres intended to make them uncomfortable, and whether or not he would or could actually harm their scientific status are irrelevant; the fact is that the victims felt very stressed to a point that they'd rather miss professional events than risk encountering the same situation again. Needless to say, it is the responsibility of senior members of our community to avoid putting less senior members in such a position. Our current involvement with this issue was triggered by an invitation Yuval Peres received to give a plenary talk at an international conference next year. We felt that this invitation sends a highly undesirable message to our community in general, and to the women he harassed in particular, as if his transgressions are considered unimportant. We sent an email conveying our concern to the organizers of the conference, suggesting that they disinvite him. With our permission, they forwarded a version of our letter (in which we made changes in order to protect the identity of the women involved) to Yuval Peres. They did not reveal our identity, rather they told him that this is a letter from "senior members of the community". In our letter we included a paragraph describing a general principle that should be followed. The principle is: *A senior researcher should not approach a junior researcher with an invitation that may be viewed as intimate or personal unless such an invitation was issued in the past by this specific junior to that specific senior. The point being that even if the senior researcher has no intimate/personal intentions, such intentions may be read by the junior researcher, placing the junior in an awkward situation and possibly causing them great distress. Examples for such an invitation include any invitation to a personal event in which only the senior and the junior will be present (e.g., a two-person dinner, a meeting in a private home, etc).* Yuval's reply was rather laconic, in particular, he did not address the issue of his behavior in the past couple of years. However, he did write: "I certainly embrace the principle described in boldface in the letter. This seems to be the right approach for any senior scientist these days." The reason we are copying this to all of you (as opposed, for example, to using bcc) is related to the i slanders ' paradox : we believe that the fact that everyone knows that everyone knows is a significant boost to holding Yuval Peres accountable for his future actions. We're also bcc'ing several young women who already aware of Yuval Peres's actions, in order to keep them in the know too. We understand that sending this out to a large number of people without offering Yuval Peres the chance to respond may be considered unfair. However, after weighing the pros and cons carefully we believe this is a good course of action. First of all, because it is clear that the victims did not invent his offers and their ensuing feelings of anxiety and stress. Secondly, we know that Yuval Peres has been confronted in a face to face conversation by a senior colleague, and it did not end his behavior, so we think it's important to stay vigilant in protecting the younger members of our community. Thirdly, the information in this letter will reach (or has already reached) almost all of you in any case, so the main effect of the letter is making what everyone knows into public knowledge. Finally, although his response to the organizers did include the minimum of declaring he accepts the guiding principle that we stated, it did not include any reference to the ongoing behavior we described - neither regret nor concern nor denial. So it's not easy to assume that he truly intends to mend his ways. We hope that our actions will contribute to the future of our community as an environment that offers all a pleasant and non-threatening atmosphere. Sincerely, Irit Dinur, Ehud Friedgut, Oded Goldreich -------------- next part -------------- An HTML attachment was scrubbed... URL: From reingold at stanford.edu Wed Nov 28 06:45:14 2018 From: reingold at stanford.edu (Omer Reingold) Date: Wed, 28 Nov 2018 06:45:14 -0800 Subject: [theory-seminar] Sexual harassment In-Reply-To: References: Message-ID: Dear all, In the name of fairness, I am including below a response from Yuval Peres to the email I forwarded before. I suggest that anybody who shared my own email would do the same. As you can imagine, there is a considerable amount of discussion on the original email list. I will not share any additional parts of this discussion or any additional back and forth with Yuval as my point goes way beyond his case. I am hoping that my emails are not flooding uncomfortable or painful memories to any of you (as it is my understanding that experiences of harrastment are much more common than we would like to believe). Let me conclude by reiterating that each and every one of the theory faculty as well as a multitude of resources at Stanford are committed to your support and to a safe and welcoming work environment. Take care, Omer >From Yuval Peres: ----------- Dear Ehud, Irit and Oded, Dear email recipients: This is my community, and I greatly appreciate each and every one of you. As you can imagine, I am sad to see this email but understand it arises from genuine concern of the authors. (I do wish they had written to me directly rather than through intermediaries). I disagree with some claims in the email but let me start by emphasizing that I embrace the passage: *A senior researcher should not approach a junior researcher with an invitation that may be viewed as intimate or personal unless such an invitation was issued in the past by this specific junior to that specific senior. The point being that even if the senior researcher has no intimate/personal intentions, such intentions may be read by the junior researcher, placing the junior in an awkward situation and possibly causing them great distress. Examples for such an invitation include any invitation to a personal event in which only the senior and the junior will be present (e.g., a two-person dinner, a meeting in a private home, etc).* *I regret all cases in the past where I have not followed this principle.* I had no intention to harass anyone but must have been tone deaf not to recognize that I was making some people very uncomfortable. As I wrote above, I promise to adhere to this principle in the future. In order to show that I am not trivializing the concerns of Ehud, Irit and Oded*, I will regretfully rescind my acceptance to deliver a keynote talk in the conference that sparked their message*. I apologize to the organizers of that conference and wrote to them separately. I have collaborated with about 300 researchers in my career, many of them women, and most of my success is due to those collaborations. (A lot of those collaborations took place in two-person lunches and dinners but usually when the collaborators knew each other well). In particular, I consider my early work with Claire Mathieu and my recent book with Anna Karlin as some of the high points of my career. In the last SODA/ANALCO I gave four talks, three of them based on collaborations with brilliant young women. I completely agree that it is crucial that we present a welcoming atmosphere to these women. If any one of you has further suggestions, you are very welcome to write to me personally at this address. Yours, Yuval ----------------------------------------- On Tue, Nov 27, 2018, 3:01 PM Omer Reingold Hello everyone, > > I am forwarding the email below, regarding the conduct of Yuval Peres, > partly as a fair public warning to our community. Another reason is to > emphasize again that sexual harassment and sexual misconduct go beyond the > narrow definitions of past generations, and for a good reason. As we and > others discussed repeatedly, sexual misconduct harms individual and hurts > the community (and thus hurts science as well). We can argue about the > specific rules to apply but the bottom line is that we should all be able > to share in the immense intellectual excitement that is TOC and the > closeness between collaborators that it brings without this intellectual > passion and closeness be misconstrued as anything else (in the spirit of > this rather old post > ). > Finally, I want to remind everyone (and especially students), that you need > not be alone if you have been hurt (on campus, in a conference or elsewhere > as part of your work and even independent of work). All of the theory > faculty are here to support and there are multiple resources in CS and on > campus. Just contact whoever you feel most comfortable with. > > Best wishes, > Omer > > > ---------- Forwarded message --------- > From: Ehud Friedgut > Date: Tue, Nov 27, 2018 at 5:07 AM > Subject: Sexual harassment > To: ofer zeitouni , Itai Benjamini < > itai.benjamini at gmail.com>, Ronen Eldan , David > Peleg , Michal Irani < > michal.irani at weizmann.ac.il>, Robert Krauthgamer < > robert.krauthgamer at weizmann.ac.il>, Jennifer Chayes , > Christian Borgs , Anna Karlin < > karlin at cs.washington.edu>, Ronitt Rubinfeld , Noga > Alon , Benjamin Sudakov , > Michael Krivelevich , Asaf Shapira < > asafico at post.tau.ac.il>, Michal Karonski , Andrzej > Rucinski , Wojtek Samotij , > Ron Peled , James R. Lee , > Nati Linial , Avi Wigderson , Gil Kalai < > gil.kalai at gmail.com>, Penny Haxell , Tamar > Ziegler , Dorit Aharonov < > doria at cs.huji.ac.il>, , , < > reingold at stanford.edu>, , , < > shafi.goldwasser at weizmann.ac.il>, , < > salil_vadhan at harvard.edu>, > Cc: Irit Dinur , Oded Goldreich < > oded.goldreich at weizmann.ac.il> > > > Hello all, > > This is an email composed by Irit Dinur, Oded Goldreich and me. > The purpose of this email is to share with you concerns that we had > regarding the unethical behavior of Yuval Peres. The behavior we are > referring to includes several recent incidents from the past few years, on > top of the two ?big? cases of sexual harassment that led to severe > sanctions against him by his employer, Microsoft, and to the termination of > his connections with the University of Washington. > > Together with two colleagues who are highly regarded and trusted by us, we > have first and second-hand testimonies (by people we trust without a shed > of doubt) of at least five additional cases of him approaching junior > female scientists, some of them students, with offers of intimate > nature, behavior that has caused its victims quite a bit of distress since > these offers were "insistent". > > While the examples that we encountered from the last few years do not fall > under the category of sexual harassment from a legal point of view, they > certainly caused great discomfort to the victims, who were young female > scientists, putting them in a highly awkward situation, and creating an > atmosphere that they'd rather avoid (i.e., they would rather miss a > conference or a lecture than risk being subjected to repeated intimate > offers by him). > > We wish to stress that his aggressive advances toward young women, usually > with no previous friendly connections with him, puts them in a vulnerable > position of fearing to cross a senior scientist who might have an impact on > their career, which is at a fragile stage. We believe that the questions of > whether or not Yuval Peres intended to make them uncomfortable, and whether > or not he would or could actually harm their scientific status are > irrelevant; the fact is that the victims felt very stressed to a point that > they'd rather miss professional events than risk encountering the same > situation again. Needless to say, it is the responsibility of senior > members of our community to avoid putting less senior members in such a > position. > > > > Our current involvement with this issue was triggered by an invitation > Yuval Peres received to give a plenary talk at an international conference > next year. We felt that this invitation sends a highly undesirable message > to our community in general, and to the women he harassed in particular, as > if his transgressions are considered unimportant. > > We sent an email conveying our concern to the organizers of the > conference, suggesting that they disinvite him. With our permission, they > forwarded a version of our letter (in which we made changes in order to > protect the identity of the women involved) to Yuval Peres. They did not > reveal our identity, rather they told him that this is a letter from > "senior members of the community". In our letter we included a paragraph > describing a general principle that should be followed. The principle is: > > > > *A senior researcher should not approach a junior researcher with an > invitation that may be viewed as intimate or personal unless such an > invitation was issued in the past by this specific junior to that specific > senior. The point being that even if the senior researcher has no > intimate/personal intentions, such intentions may be read by the junior > researcher, placing the junior in an awkward situation and possibly causing > them great distress. Examples for such an invitation include any invitation > to a personal event in which only the senior and the junior will be present > (e.g., a two-person dinner, a meeting in a private home, etc).* > > > > Yuval's reply was rather laconic, in particular, he did not address the > issue of his behavior in the past couple of years. However, he did write: > > > "I certainly embrace the principle described in boldface in the letter. > > This seems to be the right approach for any senior scientist these days." > > > > > > The reason we are copying this to all of you (as opposed, for example, to > using bcc) is related to the i > > slanders > ' > paradox > : > we believe that the fact that everyone knows that everyone knows is a > significant boost to holding Yuval Peres accountable for his future > actions. We're also bcc'ing several young women who already aware of Yuval > Peres's actions, in order to keep them in the know too. > > > > > > We understand that sending this out to a large number of people without > offering Yuval Peres the chance to respond may be considered unfair. > However, after weighing the pros and cons carefully we believe this is a > good course of action. First of all, because it is clear that the victims > did not invent his offers and their ensuing feelings of anxiety and stress. > Secondly, we know that Yuval Peres has been confronted in a face to face > conversation by a senior colleague, and it did not end his behavior, so we > think it's important to stay vigilant in protecting the younger members of > our community. Thirdly, the information in this letter will reach (or has > already reached) almost all of you in any case, so the main effect of the > letter is making what everyone knows into public knowledge. Finally, > although his response to the organizers did include the minimum of > declaring he accepts the guiding principle that we stated, it did not > include any reference to the ongoing behavior we described - neither regret > nor concern nor denial. So it's not easy to assume that he truly intends to > mend his ways. > > > > We hope that our actions will contribute to the future of our community as > an environment that offers all a pleasant and non-threatening atmosphere. > > > Sincerely, > > Irit Dinur, Ehud Friedgut, Oded Goldreich > -------------- next part -------------- An HTML attachment was scrubbed... URL: From ofirgeri at stanford.edu Wed Nov 28 09:25:34 2018 From: ofirgeri at stanford.edu (Ofir Geri) Date: Wed, 28 Nov 2018 17:25:34 +0000 Subject: [theory-seminar] Theory Seminar (11/28): Urmila Mahadev In-Reply-To: References: Message-ID: Reminder: Urmila Mahadev's talk is today at 3pm in Gates 463A. ________________________________ From: Ofir Geri Sent: Sunday, November 25, 2018 11:24:46 PM To: thseminar at cs.stanford.edu Subject: Theory Seminar (11/28): Urmila Mahadev Hi all, This Wednesday, Urmila Mahadev (UC Berkeley) will be giving a theory seminar talk on Classical Verification of Quantum Computations (abstract below). The talk will be at 3:00 PM in Gates 463A. Please note that this week's talk is on Wednesday (and there will be no theory seminar on Friday). Hope to see you there! Ofir Classical Verification of Quantum Computations Speaker: Urmila Mahadev (UC Berkeley) We present the first protocol allowing a classical computer to interactively verify the result of an efficient quantum computation. We achieve this by constructing a measurement protocol, which allows a classical string to serve as a commitment to a quantum state. The protocol forces the prover to behave as follows: the prover must construct an n qubit state of his choice, non-adaptively measure each qubit in the Hadamard or standard basis as directed by the verifier, and report the measurement results to the verifier. The soundness of this protocol is enforced based on the assumption that the learning with errors problem is computationally intractable for efficient quantum machines. -------------- next part -------------- An HTML attachment was scrubbed... URL: