Remark 3.7 . [03NU]
Original official author HTML, exact retained edition. Historical TeX conversion verdicts remain unchanged. Cited-edition alignment and mathematical self-containment are not assessed.
Complete original source context · Original author HTML
Remark 3.7.
A partial verification of Conjecture 3.6 in the case is provided by Haug [28]. He defines a version of the derived Fukaya category in which the objects are twisted complexes built out of pairs for a compact, spin, graded, embedded Lagrangian in , and a local system, and proves that is idempotent complete.
Haug remarks [28, §1] that for , including local systems has the effect of making idempotent complete, and that would not be idempotent complete if we took objects to be twisted complexes of Lagrangians rather than pairs . This shows that including local systems in objects is necessary for our programme, since otherwise Conjecture 3.6 and hence Conjecture 3.2 would be false even for . We will see in §3.4 how nontrivial local systems are needed for some kinds of surgeries.
Haug’s definition of is not quite the same as ours. He does not include bounding cochains in his objects (the simplicity of dimension 1 permits this). He fixes . His local systems [28, §3.1.1] are not -local systems, as in §2.5, but -local systems of arbitrary finite rank, such that (roughly) the eigenvalues of lie in to leading order.
I expect this should be related to our definition of as follows. In dimension 1, the combination of a rank one -local system and a bounding cochain is essentially equivalent to a rank one -local system satisfying Haug’s condition, where the holonomies satisfy for . Also, I expect that for , considering rank one local systems on immersed Lagrangians has a similar effect to considering higher rank local systems on embedded Lagrangians.