PIPages
Labs

Shachar Lovett

University of California-San Diego, CA·Computer Science

Mathematicians and computer scientists often face objects that are too complicated to analyze directly. A powerful response is the "structure versus randomness" paradigm: either find hidden structure in an object that makes it tractable and lets you design fast algorithms for it, or show that the object behaves enough like a random one that random-like properties can be used in place of true randomness.

Fields

Computer Science

Mathematics & Statistics

Topics

structure versus randomness

spreadness

mixing

Grants
1 known grant, through Dec 2027

What they work on

  1. Develop the theory of spreadness, a measure that no structured subset contains too many elements, into a general framework connecting existing structure-versus-randomness arguments.
  2. Formalize mixing, a measure of how two objects behave jointly under a shared operation, and combine it with spreadness to obtain improved quantitative bounds.
  3. Apply the new framework to problems in additive combinatorics, which studies additive structure in sets of numbers, and in graph theory.
  4. Use the spreadness and mixing approach to attack problems in communication complexity, the study of how many bits parties must exchange, and to design fast combinatorial algorithms.

More about the research

In the cleanest situations the two ideas are complements, with randomness appearing exactly where structure is absent. This project develops a new route through that paradigm, aimed at much better quantitative bounds than are currently known.

Why it matters

Sharper quantitative tools for separating structure from randomness could improve bounds on long-standing problems in combinatorics and complexity and speed up widely used combinatorial algorithms. The work also strengthens the bridge between mathematics and theoretical computer science, letting techniques developed in one field be applied in the other.

Known grants

From NIH and NSF research grants. Labs often have other funding we can't see.

Collaborative Research: CCF: AF: Small: New Frontiers in Structures vs Randomness with Applications to Combinatorics, Complexity, Algorithms

NSF · Jan 2025 – Dec 2027

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Thomas Kelly

Georgia Institute of Technology, GA·Mathematics & Statistics

Use randomness and the probabilistic method to prove new results on embedding structures such as Hamilton cycles in graphs and hypergraphs, networks where an edge can join several points.

The school

University of California-San Diego: 84 labs on PI Pages, $1.9B a year on research, 637 research doctorates a year.

More about University of California-San Diego

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