3 Search Results for "Macbeth, Heather"

Document
DOI: 10.4230/LIPIcs.ITP.2023.23
A Formalisation of Gallagher’s Ergodic Theorem

Authors: Oliver Nash

Published in: LIPIcs, Volume 268, 14th International Conference on Interactive Theorem Proving (ITP 2023)

Abstract
Gallagher’s ergodic theorem is a result in metric number theory. It states that the approximation of real numbers by rational numbers obeys a striking "all or nothing" behaviour. We discuss a formalisation of this result in the Lean theorem prover. As well as being notable in its own right, the result is a key preliminary, required for Koukoulopoulos and Maynard’s stunning recent proof of the Duffin-Schaeffer conjecture.
Cite as

Oliver Nash. A Formalisation of Gallagher’s Ergodic Theorem. In 14th International Conference on Interactive Theorem Proving (ITP 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 268, pp. 23:1-23:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)

Copy BibTex To Clipboard

@InProceedings{nash:LIPIcs.ITP.2023.23,
  author =	{Nash, Oliver},
  title =	{{A Formalisation of Gallagher’s Ergodic Theorem}},
  booktitle =	{14th International Conference on Interactive Theorem Proving (ITP 2023)},
  pages =	{23:1--23:16},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-284-6},
  ISSN =	{1868-8969},
  year =	{2023},
  volume =	{268},
  editor =	{Naumowicz, Adam and Thiemann, Ren\'{e}},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2023.23},
  URN =		{urn:nbn:de:0030-drops-183981},
  doi =		{10.4230/LIPIcs.ITP.2023.23},
  annote =	{Keywords: Lean proof assistant, measure theory, metric number theory, ergodicity, Gallagher’s theorem, Duffin-Schaeffer conjecture}
}
Document
DOI: 10.4230/LIPIcs.ITP.2022.9
Formalising Szemerédi’s Regularity Lemma in Lean

Authors: Yaël Dillies and Bhavik Mehta

Published in: LIPIcs, Volume 237, 13th International Conference on Interactive Theorem Proving (ITP 2022)

Abstract
Szemerédi’s Regularity Lemma is a fundamental result in graph theory with extensive applications to combinatorics and number theory. In essence, it says that all graphs can be approximated by well-behaved unions of random bipartite graphs. We present a formalisation in the Lean theorem prover of a strong version of this lemma in which each part of the union must be approximately the same size. This stronger version has not been formalised previously in any theorem prover. Our proof closely follows the pen-and-paper method, allowing our formalisation to provide an explicit upper bound on the number of parts. An application of this lemma is also formalised, namely Roth’s theorem on arithmetic progressions in qualitative form via the triangle removal lemma.
Cite as

Yaël Dillies and Bhavik Mehta. Formalising Szemerédi’s Regularity Lemma in Lean. In 13th International Conference on Interactive Theorem Proving (ITP 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 237, pp. 9:1-9:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)

Copy BibTex To Clipboard

@InProceedings{dillies_et_al:LIPIcs.ITP.2022.9,
  author =	{Dillies, Ya\"{e}l and Mehta, Bhavik},
  title =	{{Formalising Szemer\'{e}di’s Regularity Lemma in Lean}},
  booktitle =	{13th International Conference on Interactive Theorem Proving (ITP 2022)},
  pages =	{9:1--9:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-252-5},
  ISSN =	{1868-8969},
  year =	{2022},
  volume =	{237},
  editor =	{Andronick, June and de Moura, Leonardo},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2022.9},
  URN =		{urn:nbn:de:0030-drops-167185},
  doi =		{10.4230/LIPIcs.ITP.2022.9},
  annote =	{Keywords: Lean, formalisation, formal proof, graph theory, combinatorics, additive combinatorics, Szemer\'{e}di’s Regularity Lemma, Roth’s Theorem}
}
Document
DOI: 10.4230/LIPIcs.ITP.2022.10
Formalized functional analysis with semilinear maps

Authors: Frédéric Dupuis, Robert Y. Lewis, and Heather Macbeth

Published in: LIPIcs, Volume 237, 13th International Conference on Interactive Theorem Proving (ITP 2022)

Abstract
Semilinear maps are a generalization of linear maps between vector spaces where we allow the scalar action to be twisted by a ring homomorphism such as complex conjugation. In particular, this generalization unifies the concepts of linear and conjugate-linear maps. We implement this generalization in Lean’s mathlib library, along with a number of important results in functional analysis which previously were impossible to formalize properly. Specifically, we prove the Fréchet-Riesz representation theorem and the spectral theorem for compact self-adjoint operators generically over real and complex Hilbert spaces. We also show that semilinear maps have applications beyond functional analysis by formalizing the one-dimensional case of a theorem of Dieudonné and Manin that classifies the isocrystals over an algebraically closed field with positive characteristic.
Cite as

Frédéric Dupuis, Robert Y. Lewis, and Heather Macbeth. Formalized functional analysis with semilinear maps. In 13th International Conference on Interactive Theorem Proving (ITP 2022). Leibniz International Proceedings in Informatics (LIPIcs), Volume 237, pp. 10:1-10:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2022)

Copy BibTex To Clipboard

@InProceedings{dupuis_et_al:LIPIcs.ITP.2022.10,
  author =	{Dupuis, Fr\'{e}d\'{e}ric and Lewis, Robert Y. and Macbeth, Heather},
  title =	{{Formalized functional analysis with semilinear maps}},
  booktitle =	{13th International Conference on Interactive Theorem Proving (ITP 2022)},
  pages =	{10:1--10:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-252-5},
  ISSN =	{1868-8969},
  year =	{2022},
  volume =	{237},
  editor =	{Andronick, June and de Moura, Leonardo},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops-dev.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2022.10},
  URN =		{urn:nbn:de:0030-drops-167191},
  doi =		{10.4230/LIPIcs.ITP.2022.10},
  annote =	{Keywords: Functional analysis, Lean, linear algebra, semilinear, Hilbert space}
}
  • Refine by Author
  • 1 Dillies, Yaël
  • 1 Dupuis, Frédéric
  • 1 Lewis, Robert Y.
  • 1 Macbeth, Heather
  • 1 Mehta, Bhavik
  • Show More...

  • Refine by Classification
  • 1 Mathematics of computing → Extremal graph theory
  • 1 Mathematics of computing → Functional analysis
  • 1 Mathematics of computing → Probability and statistics
  • 1 Theory of computation → Interactive proof systems

  • Refine by Keyword
  • 2 Lean
  • 1 Duffin-Schaeffer conjecture
  • 1 Functional analysis
  • 1 Gallagher’s theorem
  • 1 Hilbert space
  • Show More...

  • Refine by Type
  • 3 document

  • Refine by Publication Year
  • 2 2022
  • 1 2023

Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail
© 2023-2024 Schloss Dagstuhl – LZI GmbH Imprint Privacy Contact