Computer Laboratory

Thomas Sauerwald

Reader at the Department of Computer Science, at the department since July 2013.

Director of Studies at Emmanuel College (since October 2017).

Contact Details


Dr Thomas Sauerwald
University of Cambridge
Computer Laboratory
15 JJ Thomson Avenue
Cambridge CB3 0FD
United Kingdom

Email: firstname.lastname at cl.cam.ac.uk
Phone: +44 1223 763538
Fax: +44 1223 334678
Office: FC11

Research Interests


Research Projects and Funding


I am currently the PI of a five-year project "Dynamics of Multiple, Interacting and Concurrent Markov Chains" (DYNAMIC MARCH) as part of an ERC Starting Grant funded by the European Research Council. The project started in 2016, and its aims are to explore new algorithms based on multiple random walks that are able to cope with complex data sets and networks. In 2018, I was a Mercator Fellow as part of the project "Analysis of Discrete Load Balancing on Heterogeneous Networks" (ADLON) (co-PI together with Tobias Friedrich, HPI Potsdam), funded by the German Research Council (DFG). From 2014-2015, I was the principal investigator of the project "Random Walks on Massive Graphs" supported by the Isaac Newton Trust / University of Cambridge Early Career Support Scheme.

Postdocs and Students


  • Leran Cai (PhD student, since 10/2016)
  • Dimitris Los (PhD student, since 10/2019)
  • Vladimir Milenkovic (Part II student, 2019-20)
  • Nicolas Rivera (Postdoc, since 09/2017)
  • Hayk Saribekyan (PhD student, since 10/2017)
  • John Sylvester (Postdoc, since 09/2017)
  • Vu Phan Thanh (MPhil, 2019-20)
  • Luca Zanetti (Postdoc, since 06/2017)

Selected Works


A complete list of my publications can be found at DBLP.

  • The Power of Two Choices for Random Walks: Hitting, Covering and Complexity (with Agelos Georgakopoulos, John Haslegrave and John Sylvester)
    In Proceedings of the 11th Innovations in Theoretical Computer Science (ITCS), pages 76:1-76:19, 2020.
  • Random Walks on Dynamic Graphs: Mixing Times, Hitting Times, and Return Probabilities (with Luca Zanetti)
    In Proceedings of the 46th International Colloqoium on Automata, Languages, and Programming (ICALP), pages 93:1-93:15, 2019.
  • On coalescence time in graphs--When is coalescing as fast as meeting? (with Varun Kanade and Frederik Mallmann-Trenn)
    In Proceedings of the 29th ACM-SIAM Symposium on Discrete Algorithms (SODA), pages 956--965, 2019. arxiv
  • Multiple Random Walks on Paths and Grids (with Andrej Ivaskovic, Adrian Kosowski and Dominik Pajak)
    In Proceedings of the 34th International Symposium on Theoretical Aspects of Computer Science (STACS), pages 44:1-44:14, 2017.  
  • Balls into Bins via Local Search (with Paul Bogdan, Alexandre Stauffer and He Sun)
    Random Structures & Algorithms, 48(4):681-702, 2016. Preliminary versions appeared in SODA'13, pages 16-34 and STACS'14, pages 187-198.  
  • Lock-Free Algorithms under Stochastic Schedulers (with Dan Alistarh and Milan Vojnovic)
    In Proceedings of the 34st ACM Symposium on Principles of Distributed Computing (PODC), pages 251-260, 2015.  
  • Randomized Diffusion for Indivisible Loads (with Petra Berenbrink, Colin Cooper, Tom Friedetzky and Tobias Friedrich)
    Journal of Computer and System Sciences, 81(1):159-185, 2015. Preliminary version appeared in SODA'11, pages 429-439.  
  • Randomized Rumor Spreading in Dynamic Graphs (with George Giakkoupis and Alexandre Stauffer)
    In Proceedings of the 41st International Colloquium on Automata, Languages, and Programming (ICALP), pages 495-507, 2014.
  • HIT'nDRIVE: Multi-Driver Gene Prioritization based on Hitting Time (with Raunak Shrestha, Ermin Hodzic, Jake Yeung, Kendric Wang, Phuong Dao, Shawn Anderson, Himisha Beltran, Mark A. Rubin, Colin C. Collins, Gholamreza Haffari and S. Chenk Sahinalp)
    Genome Research, 27:1573--1588, 2017. Preliminary version appeared in RECOMB'14, pages 293-306.
  • Distributed Selfish Load Balancing on Networks (with Petra Berenbrink and Martin Hoefer)
    ACM Transactions on Algorithms, 11(1): 2:1-2:29, 2014. Preliminary version appeared in SODA'11, pages 1487-1497.  
  • Quasirandom Rumor Spreading (with Benjamin Doerr and Tobias Friedrich)
    ACM Transactions on Algorithms 11(2): 9:1-9:35, 2014. Preliminary versions appeared in SODA'08, pages 773-781 and ICALP'09, pages 366-377.
  • Tight Bounds For Randomized Load Balancing on Arbitrary Network Topologies (with He Sun)
    In Proceedings of the 53rd IEEE Annual Symposium on Foundations of Computer Science (FOCS), pages 341-350, 2012. Full version available on Arxiv.  
  • Quasirandom Load Balancing (with Tobias Friedrich and Martin Gairing)
    SIAM Journal on Computing, 41(4):747-771, 2012. Preliminary version appeared in SODA'10, pages 1620-1629.  
  • Counting Arbitrary Subgraphs in Data Streams (with Daniel M. Kane, Kurt Mehlhorn and He Sun)
    In Proceedings of the 39th International Colloquium on Automata, Languages, and Programming (ICALP), pages 598-609, 2012.
  • Rumor Spreading and Vertex Expansion (with George Giakkoupis)
    In Proceedings of the 23rd ACM-SIAM Symposium on Discrete Algorithms (SODA), pages 1623-1641, 2012.
  • Ultra-Fast Rumor Spreading in Social Networks (with Nikolas Fountoulakis and Konstantinos Panagiotou)
    In Proceedings of the 23rd ACM-SIAM Symposium on Discrete Algorithms (SODA), pages 1642-1661, 2012.
  • Tight Bounds for the Cover Time of Multiple Random Walks (with Robert Elsässer)
    Theoretical Computer Science, 412(24): 2623-2641, 2011. Preliminary version appeared in ICALP'09, pages 415-426.  
  • On Mixing and Edge Expansion Properties in Randomized Broadcasting
    Algorithmica, 56(1):51-88, 2010. Preliminary version appeared in ISAAC'07, pages 196-207.
  • Expansion and the Cover Time of Parallel Random Walks
    In Proceedings of the 29th ACM Symposium on Principles of Distributed Computing (PODC), pages 315-324, 2010.  
  • Speeding Up Random Walks with Neighborhood Exploration (with Petra Berenbrink, Colin Cooper, Robert Elsässer, Tomasz Radzik)
    In Proceedings of the 21st ACM-SIAM Symposium on Discrete Algorithms (SODA), pages 1422-1435, 2010.  
  • The Impact of Randomization in Smoothing Networks (with Marios Mavronicolas)
    Distributed Computing, 22(5-6), pages 381-411, 2010. Preliminary version appeared in PODC'08, pages 345-354.    
  • Near-Perfect Load Balancing by Randomized Rounding (with Tobias Friedrich)
    In Proceedings of the 41st Annual ACM Symposium on Theory of Computing (STOC), pages 121-130, 2009.  

Program Committees


SODA 2021, ICALP 2020, IJCAI 2019, PODC 2019, SPAA 2018, STACS 2018, ICALP 2017, IPDPS 2017, SIROCCO 2016, ESA 2016, PODC 2016, SPAA 2016, ISAAC 2015, FCT 2015, IPDPS 2015, SODA 2015, DISC 2014, STACS 2013, SPAA 2012, SIROCCO 2012, SIROCCO 2010

Editorial Boards


Journal of Computer and System Sciences

Academic Activities


Teaching