PeopleofSuperintelligence

Researcher

Sebastiano Vigna

Sebastiano Vigna is a computer scientist whose work on web and social graph algorithms supports large-scale network analysis, and whose random-number research includes methods suited to machine-learning applications. He earned a mathematics degree in 1991 and a computer science PhD in 1996. His career includes coauthoring WebGraph, Layered Label Propagation, HyperBall, and BUbiNG, and publishing pseudorandom-number research on xorshift+ and LXM. As of October 2026, he is a full professor and scientific director of the University of Milan's Laboratory for Web Algorithmics.

Timeline

  1. 1991–1996

    Mathematics and computer science degrees

    He earns a mathematics degree in 1991 and a computer science PhD in 1996, both from the University of Milan.

  2. 2004–2010

    WebGraph and social graph ordering

    In 2004, he coauthors WebGraph, a framework of codes, algorithms, and tools for managing large web graphs. In 2010, he and collaborators present Layered Label Propagation, an algorithm that orders large web and social graphs to improve compression.

  3. 2013

    HyperBall for very large graphs

    With Paolo Boldi, he presents HyperBall in 2013, using HyperLogLog counters to estimate graph centralities quickly and accurately with low memory use.

  4. 2014

    Xorshift+ and SplitMix64

    In 2014, he presents xorshift+, a 64-bit variant of XSadd that yields fast, high-quality pseudorandom generators. A Rust implementation of SplitMix64 cites his reference source code.

  5. 2016

    BUbiNG web crawler

    In 2016, he coauthors BUbiNG, an open-source, fully distributed Java crawler that scales with available resources and can crawl thousands of pages per second.

  6. 2021

    LXM generators for machine learning

    With Guy L. Steele Jr., he introduces LXM in 2021, a family of splittable pseudorandom-number generators suitable for scientific and machine-learning applications.

  7. 2025

    Filters for trillions of keys

    In 2025, he introduces ε-cost sharding for hypergraph-based static functions and filters that manage trillions of keys.

  8. As of October 2026

    Professor and lab director

    As of October 2026, he is a full professor and scientific director of the University of Milan's LAW lab, which studies algorithms for the web and social networks.

Sources and credits

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  1. Sebastiano Vigna vigna.di.unimi.it. Checked 15 October 2026.
  2. Laboratory for Web Algorithmics law.di.unimi.it. Checked 15 October 2026.
  3. Layered Label Propagation: A MultiResolution Coordinate-Free Ordering for Compressing Social Networks arxiv.org. Checked 15 October 2026.
  4. In-Core Computation of Geometric Centralities with HyperBall: A Hundred Billion Nodes and Beyond arxiv.org. Checked 15 October 2026.
  5. Further scramblings of Marsaglia's xorshift generators arxiv.org. Checked 15 October 2026.
  6. SplitMix64 in xoroshiro::rng - Rust docs.rs. Checked 15 October 2026.
  7. BUbiNG: Massive Crawling for the Masses arxiv.org. Checked 15 October 2026.
  8. Sebastiano Vigna/Papers vigna.di.unimi.it. Checked 15 October 2026.
  9. ε-Cost Sharding: Scaling Hypergraph-Based Static Functions and Filters to Trillions of Keys arxiv.org. Checked 15 October 2026.
  10. LAW - Algorithmics for the Web Lab | Department of Computer Science "Giovanni degli Antoni" di.unimi.it. Checked 15 October 2026.