On the boundaries of special Lagrangian submanifolds

Date
1995
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract

An n-dimensional submanifold M in C\spn=R\sp2n is called Lagrangian if the restriction of ω to M is zero, where \limits is allowed only on operators\omega = \Sigma{\limits\sb{i}}dz\sb{i}\ \wedge\ d\bar z\sb{i}\omega = \Sigma{\limits\sb{i}}dz\sb{i}\ \wedge\ d\bar z\sb{i}. It is called special Lagrangian if the restrictions of ω and Imdz = Im(dz\sb1∧⋯∧dz\sbn) are zero. Special Lagrangian submanifolds are volume minimizing, and conversely, any minimal Lagrangian submanifold can be transformed to a special Lagrangian submanifold by a unitary transformation. This paper studies the conditions satisfied by the boundaries of special Lagrangian submanifolds. We say an n−1 dimensional submanifold N in C\spn satisfies the moment condition if ∫\sbN ϕ = 0 for any n−1 form ϕ with belonging to the differential ideal generated by ω and Imdz. By Stokes' formula, the boundary of a special Lagrangian submanifold satisfies the moment condition. In fact on C\sp2, the converse is also true, that is, a curve is the boundary of a special Lagrangian submanifold if it satisfies the moment condition. However, we show in this paper that for n≥3, there exist n−1 dimensional submanifolds which satisfy the moment condition but do not bound any special Lagrangian submanifolds. Let f be a real valued function defined on some open subset on C\spn which contains a special Lagrangian submanifold M. We show that $$\Delta\sb{M}f = d(J(\nabla f)\quad\rfloor\ {\rm Im}dz){\vert}\sb{M},$$where Δ\sbM is the Laplace operator on M and J is the standard complex structure. Using this formula and the maximum principle, we prove that if d(J(∇f)⌋ Imdz) belongs to the differential ideal generated by df, ω and Imdz, then f|\sbM attains its maximum and minimum on the boundary of M. This result is then used to produce some conditions other than the moment condition which are satisfied by the boundaries of special Lagrangian submanifolds.

Description
Degree
Doctor of Philosophy
Type
Thesis
Keywords
Mathematics
Citation

Fu, Lei. "On the boundaries of special Lagrangian submanifolds." (1995) Diss., Rice University. https://hdl.handle.net/1911/16823.

Has part(s)
Forms part of
Published Version
Rights
Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.
Link to license
Citable link to this page