Saved in:
Bibliographic Details
Main Author: Frenkler, Joachim
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2403.13498
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909143663640576
author Frenkler, Joachim
author_facet Frenkler, Joachim
contents We link the QUMOND theory with the Helmholtz-Weyl decomposition and introduce a new formula for the gradient of the Mondian potential using singular integral operators. This approach allows us to demonstrate that, under very general assumptions on the mass distribution, the Mondian potential is well-defined, once weakly differentiable, with its gradient given through the Helmholtz-Weyl decomposition. Furthermore, we establish that the gradient of the Mondian potential is an $L^p$ vector field. These findings lay the foundation for a rigorous mathematical analysis of various issues within the realm of QUMOND. Given that the Mondian potential satisfies a second-order partial differential equation, the question arises whether it has second-order derivatives. We affirmatively answer this question in the situation of spherical symmetry, although our investigation reveals that the regularity of the second derivatives is weaker than anticipated. We doubt that a similarly general regularity result can be proven without symmetry assumptions. In conclusion, we explore the implications of our results for numerous problems within the domain of QUMOND, thereby underlining their potential significance and applicability.
format Preprint
id arxiv_https___arxiv_org_abs_2403_13498
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle A mathematical foundation for QUMOND
Frenkler, Joachim
Analysis of PDEs
Astrophysics of Galaxies
Mathematical Physics
We link the QUMOND theory with the Helmholtz-Weyl decomposition and introduce a new formula for the gradient of the Mondian potential using singular integral operators. This approach allows us to demonstrate that, under very general assumptions on the mass distribution, the Mondian potential is well-defined, once weakly differentiable, with its gradient given through the Helmholtz-Weyl decomposition. Furthermore, we establish that the gradient of the Mondian potential is an $L^p$ vector field. These findings lay the foundation for a rigorous mathematical analysis of various issues within the realm of QUMOND. Given that the Mondian potential satisfies a second-order partial differential equation, the question arises whether it has second-order derivatives. We affirmatively answer this question in the situation of spherical symmetry, although our investigation reveals that the regularity of the second derivatives is weaker than anticipated. We doubt that a similarly general regularity result can be proven without symmetry assumptions. In conclusion, we explore the implications of our results for numerous problems within the domain of QUMOND, thereby underlining their potential significance and applicability.
title A mathematical foundation for QUMOND
topic Analysis of PDEs
Astrophysics of Galaxies
Mathematical Physics
url https://arxiv.org/abs/2403.13498