Download this article
 Download this article For screen
For printing
Recent Issues

Volume 30
Issue 6, 2043–2429
Issue 5, 1611–2042
Issue 4, 1203–1610
Issue 3, 835–1201
Issue 2, 389–833
Issue 1, 1–388

Volume 29, 9 issues

Volume 28, 9 issues

Volume 27, 9 issues

Volume 26, 8 issues

Volume 25, 7 issues

Volume 24, 7 issues

Volume 23, 7 issues

Volume 22, 7 issues

Volume 21, 6 issues

Volume 20, 6 issues

Volume 19, 6 issues

Volume 18, 5 issues

Volume 17, 5 issues

Volume 16, 4 issues

Volume 15, 4 issues

Volume 14, 5 issues

Volume 13, 5 issues

Volume 12, 5 issues

Volume 11, 4 issues

Volume 10, 4 issues

Volume 9, 4 issues

Volume 8, 3 issues

Volume 7, 2 issues

Volume 6, 2 issues

Volume 5, 2 issues

Volume 4, 1 issue

Volume 3, 1 issue

Volume 2, 1 issue

Volume 1, 1 issue

The Journal
About the journal
Ethics and policies
Peer-review process
 
Submission guidelines
Submission form
Editorial board
 
Subscriptions
 
ISSN (electronic): 1364-0380
ISSN (print): 1465-3060
 
Author index
To appear
 
Other MSP journals
Corks for exotic diffeomorphisms

Vyacheslav Krushkal, Anubhav Mukherjee, Mark Powell and Terrin Warren

Geometry & Topology 30 (2026) 2297–2335
Abstract

We prove a localization theorem for exotic diffeomorphisms, showing that every diffeomorphism of a compact simply connected 4-manifold that is isotopic to the identity after stabilizing with one copy of S2 × S2 is smoothly isotopic to a diffeomorphism that is supported on a contractible submanifold. For those that require more than one copy of S2 × S2, we prove that the diffeomorphism can be isotoped to one that is supported in a submanifold homotopy equivalent to a wedge of 2-spheres, with null-homotopic inclusion map. We investigate the implications of these results by applying them to known exotic diffeomorphisms.

Keywords
$4$-manifolds, diffeomorphisms, corks
Mathematical Subject Classification
Primary: 57K40, 57N37, 57R58
References
Publication
Received: 10 September 2024
Revised: 27 January 2026
Accepted: 25 February 2026
Published: 31 July 2026
Proposed: Ciprian Manolescu
Seconded: Benson Farb, Ian Agol
Authors
Vyacheslav Krushkal
Department of Mathematics
University of Virginia
Charlottesville, VA
United States
Anubhav Mukherjee
Department of Mathematics
Princeton University
Princeton, NJ
United States
Mark Powell
School of Mathematics and Statistics
University of Glasgow
Glasgow
United Kingdom
Terrin Warren
Department of Mathematics
California Polytechnic State University
San Luis Obispo, CA
United States

Open Access made possible by participating institutions via Subscribe to Open.