2023/09/19 by W. E. Bies, Bies, William
Computer Science · Physics and Astronomy · #Computational Physics and Python Applications #Cosmology and Gravitation Theories #Differential Geometry (math.DG) #FOS: Mathematics #FOS: Physical sciences #Mathematical Physics (math-ph) #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.2310.04214
openalex publication_date 2023/09/19 · openalex created_date 2024/01/13 · openalex updated_date 2026/07/28
Differential geometry may be generalized to allow infinitesimals to any order. The purpose of the present contribution is to show that the theory so developed expands received geometrical ideas in an interesting way, rich in potential for future exploration. The first order of business is to furnish the notion of a higher tangent vector, as defined abstractly by means of commutative algebra, with a workable interpretation in terms of spatial intuition. Then we introduce the differential calculus of the so-called jet connection, viz., an extension of the usual affine connection that takes higher tangent vectors as its arguments -- thereby enabling us to give a sense to parallel transport in the direction of a higher tangent, what has (to our knowledge) never been entertained before. After generalizing the Riemannian metric tensor to include a dependence up to any order in the infinitesimals, we arrive at natural analogues of the Levi-Civita connection and the Riemannian curvature tensor which display novel phenomena rooted in interactions among infinitesimals differing in order. Finally on the integral side, an intrinsic theory of integration adapted to integrands possibly of higher than first order in the differentials is developed, with a view towards eventually defining an action functional that will be applicable in the general theory of relativity.