Theoretical Computer Science at UW Madison

What is TCS? Study of the fundamental capabilities and limitations of computing Which tasks can be solved? How efficiently? What is the power of parallelism, randomness, quantum interference, … ? Emphasis on provable results

What is TCS? Study of the fundamental capabilities and limitations of computing Which tasks can be solved? How efficiently? What is the power of parallelism, randomness, quantum interference, … ? Emphasis on provable results Applications: economics, machine learning, networking, cryptography, …

Why study TCS? Fun, like puzzle solving! Lays the foundations of computer science Turing Awards in Theory: Dijkstra, Knuth, Rabin and Scott, Cook, Karp, Hopcroft and Tarjan, Hartmanis and Stearns, Blum, Pnueli, Yao, Rivest and Shamir and Adleman, Valiant, Goldwasser and Micali, Diffie and Hellman.

Why study TCS? Fun, like puzzle solving! Lays the foundations of computer science Turing Awards in Theory: Dijkstra, Knuth, Rabin and Scott, Cook, Karp, Hopcroft and Tarjan, Hartmanis and Stearns, Blum, Pnueli, Yao, Rivest and Shamir and Adleman, Valiant, Goldwasser and Micali, Diffie and Hellman. Many exciting recent advances in Technology, Science, Mathematics, … Benefitting society … e.g. market efficiency, epidemiology, kidney exchange, fairness & privacy, …

Theory faculty Shuchi Jin-Yi Eric Chawla Cai Bach Dieter Christos van Melkebeek Christos Tzamos

Theory students ~10 Ph.D. students

Theory students Researchers at Google, Microsoft Research, IBM, … ~10 Ph.D. students Alumni in industry and academia Researchers at Google, Microsoft Research, IBM, … Faculty at IISc, Sydney, Edinburgh, Indiana State, … Postdocs at Simons Institute (Berkeley), Caltech, Maryland, Cambridge …

Theory students Researchers at Google, Microsoft Research, IBM, … ~10 Ph.D. students Alumni in industry and academia Researchers at Google, Microsoft Research, IBM, … Faculty at IISc, Sydney, Edinburgh, Indiana State, … Postdocs at Simons Institute (Berkeley), Caltech, Maryland, Cambridge … Many awards Ben Miller Cisco Fellowship, 2016-18 Heng Guo, Ph.D. 2015 EATCS Doctoral Dissertation Award, 2016 Simons Fellowship, 2013-15 CS grad student research award, 2016 Balu Sivan, Ph.D. 2013 SIGecom Doctoral Dissertation Award, 2014 CS grad student research award, 2014

Research of Prof. Bach Algorithms in number theory, algebra, and combinatorics Math Tools: Analytic Number Theory, Algebraic Geometry, Classical Analysis, . . . Applications: Public Key Cryptography, Computer Algebra, Pseudo- Random Numbers, Quantum Computation Greatest hits: Hedging Fame: Algorithms that work or the ERH is false. Factored random numbers: You can get flat cryptographic key spaces. Quantum random walks: In Schrodinger's casino, you can play forever!

Research of Prof. Cai Computational Complexity Theory Complexity dichotomy theorems for counting problems. Graph Homomorphisms with Complex Values: A Dichotomy Theorem Complexity of Counting CSP with Complex Weights Matchgate Theory and Holant problems.

Research of Prof. Chawla Algorithmic game theory and computational economics Design of auctions, posted pricings, and other economic mechanisms Quantifying the quality of equilibria in games Stochastic/online optimization Decision-making without complete knowledge of the input Algorithmic fairness E.g., can we ensure that Google shows the same job ads to men and women?

Reseach of Prof. van Melkebeek Derandomization: connections with circuit lower bounds, polynomial identity testing, isolation. Lower bounds for NP-hard problems on deterministic, randomized, and quantum machines Lower bounds for kernelization and compression.

Research of Prof. Tzamos Algorithmic game theory and computational economics Design of efficient auctions and other economic mechanisms Mechanism design without money Learning Theory Estimation problems in high dimensions How quickly do classical algorithms like EM converge? Fine grained complexity Pinning down the exact complexity of poly-time solvable problems

Prof. Ilias Diakonikolas algorithms, learning, statistics, and applied probability. tradeoff between statistical efficiency, computational efficiency, and robustness for fundamental problems in machine learning. Joining Department in Fall 2019

More Info Webpage: Drop by to see us this afternoon! http://www.cs.wisc.edu/areas/theory Drop by to see us this afternoon! Faculty offices on CS 4th floor