The generalized Dixmier conjecture and the two-dimensional Jacobian conjecture
Abstract
We prove that the two-dimensional Jacobian conjecture JC2 implies the generalized Dixmier conjecture DC'1 for the first Weyl algebra A1, which states, in one of several equivalent formulations, that every endomorphism of the two-by-two matrix ring Mat2(A1) is invertible. For the converse, an endomorphism of ๐ธ2โ with Jacobian one gives rise to a family of holonomic A2-modules over finite fields. One needs to lift this family to an A2-module in characteristic zero with the prescribed arithmetic support. The existence of such a lift is a special case of Kontsevich's conjecture on holonomic ๐-modules with prescribed arithmetic support. We prove that in this special situation such a lift is unique whenever it exists. If these lifts exists for every endomorphism with Jacobian one, then DC'1 implies JC2. For every nโฅ 3, we construct a Lagrangian subvariety of T*๐ธn that provides a counterexample to Kontsevich's conjecture. The counterexamples arise from the graph of a noninvertible symplectic endomorphism of ๐ธ4 constructed by Long. We also present a different strategy for lifting ๐-modules associated with a Jacobian-one endomorphism of ๐ธ2โ to characteristic zero via ultraproducts and show that the existence of a characteristic-zero lift in this setting is equivalent to the uniform boundedness of the Berest--Wilson invariants of these A2-modules, regarded as left A1-modules. Finally, we study two other conjectures of Kontsevich on arithmetic support, giving a counterexample to one and partial results on the other.
Related
- Some arithmetical aspects of the two dimensional Jacobian Conjecture
- An elementary way to find a counterexample to the Jacobian Conjecture
- Counterexamples to the Jacobian Conjecture from the viewpoint of lineability
- Global injectivity and real Jacobian conjecture in โn
- Poincarรฉ compactifications of pullbacks of parallel vector fields under counterexamples to the real Jacobian conjecture
BibTeX
@misc{kanelbelov2026generalized,
title = {{The generalized Dixmier conjecture and the two-dimensional Jacobian conjecture}},
author = {Alexey Kanel-Belov and Timofey Fedorov},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.33919},
eprint = {2610.33919},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.33919},
}
RIS
TY - UNPB
TI - The generalized Dixmier conjecture and the two-dimensional Jacobian conjecture
AU - Alexey Kanel-Belov
AU - Timofey Fedorov
PY - 2026
DA - 2026/10/24
PB - arXiv
DO - 10.48550/arxiv.2610.33919
UR - https://arxiv.org/abs/2610.33919
AB - We prove that the two-dimensional Jacobian conjecture JC_2 implies the generalized Dixmier conjecture DC'_1 for the first Weyl algebra A_1, which states, in one of several equivalent formulations, that every endomorphism of the two-by-two matrix ring Mat_2(A_1) is invertible. For the converse, an endomorphism of ๐ธ^2_โ with Jacobian one gives rise to a family of holonomic A_2-modules over finite fields. One needs to lift this family to an A_2-module in characteristic zero with the prescribed arithmetic support. The existence of such a lift is a special case of Kontsevich's conjecture on holonomic ๐-modules with prescribed arithmetic support. We prove that in this special situation such a lift is unique whenever it exists. If these lifts exists for every endomorphism with Jacobian one, then DC'_1 implies JC_2. For every nโฅ 3, we construct a Lagrangian subvariety of T^*๐ธ^n that provides a counterexample to Kontsevich's conjecture. The counterexamples arise from the graph of a noninvertible symplectic endomorphism of ๐ธ^4 constructed by Long. We also present a different strategy for lifting ๐-modules associated with a Jacobian-one endomorphism of ๐ธ^2_โ to characteristic zero via ultraproducts and show that the existence of a characteristic-zero lift in this setting is equivalent to the uniform boundedness of the Berest--Wilson invariants of these A_2-modules, regarded as left A_1-modules. Finally, we study two other conjectures of Kontsevich on arithmetic support, giving a counterexample to one and partial results on the other.
ER -