Saved in:
Bibliographic Details
Main Author: Chen, Xuantao
Format: Preprint
Published: 2022
Subjects:
Online Access:https://arxiv.org/abs/2201.08280
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866913945035472896
author Chen, Xuantao
author_facet Chen, Xuantao
contents We study the initial value problem of the Einstein-Dirac system, and show the stability of the Minkowski solution in the massless case with the use of generalized wave coordinates. This requires the understanding of the Dirac equation in curved spacetime, for which we establish various estimates. The proof is based on the vector-field method which is widely used in works on the stability of Minkowski problems for other Einstein-coupled systems. Under a specific choice of the tetrad, we show that components of the Dirac field satisfy a quasilinear wave equation, by resolving a potential loss of derivative problem. We also show that the semilinear nonlinearity of this equation behaves like a null form. In this way, we obtain the sharp decay of the field along the light cone. The structure of the energy-momentum tensor causes worse behavior of some components of the metric than the vaccum case, but an additional structure shows that there is no harm to the global existence result. In addition, we develop an estimate of the Dirac equation itself adpated to the decay of the metric, as this provides better estimates in the interior compared with the estimates from the second order equation. The combination of these estimates leads to a good control of the Dirac field that helps close the proof. We shall also see how our argument here gives a proof of the wellposedness of the system in the massive case.
format Preprint
id arxiv_https___arxiv_org_abs_2201_08280
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Global stability of Minkowski spacetime for a spin-1/2 field
Chen, Xuantao
General Relativity and Quantum Cosmology
Analysis of PDEs
We study the initial value problem of the Einstein-Dirac system, and show the stability of the Minkowski solution in the massless case with the use of generalized wave coordinates. This requires the understanding of the Dirac equation in curved spacetime, for which we establish various estimates. The proof is based on the vector-field method which is widely used in works on the stability of Minkowski problems for other Einstein-coupled systems. Under a specific choice of the tetrad, we show that components of the Dirac field satisfy a quasilinear wave equation, by resolving a potential loss of derivative problem. We also show that the semilinear nonlinearity of this equation behaves like a null form. In this way, we obtain the sharp decay of the field along the light cone. The structure of the energy-momentum tensor causes worse behavior of some components of the metric than the vaccum case, but an additional structure shows that there is no harm to the global existence result. In addition, we develop an estimate of the Dirac equation itself adpated to the decay of the metric, as this provides better estimates in the interior compared with the estimates from the second order equation. The combination of these estimates leads to a good control of the Dirac field that helps close the proof. We shall also see how our argument here gives a proof of the wellposedness of the system in the massive case.
title Global stability of Minkowski spacetime for a spin-1/2 field
topic General Relativity and Quantum Cosmology
Analysis of PDEs
url https://arxiv.org/abs/2201.08280