ScalingStacks

Proof. [04CS]

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

Proof.

We analyze the moduli space integrand (39) of the Solomon functional. Applying the uniform energy bound and the wedge region bound, the first term is bounded by

|Im​∫Σe−i​θ^​F​ω|≤∫Σ|F|​ω≤Re​(F​(p))sin⁡ϵ​∫Σω≤Re​(F​(p))sin⁡ϵ​A​(N+1).|\text{Im}\int_{\Sigma}e^{-i\hat{\theta}}F\omega|\leq\int_{\Sigma}|F|\omega\leq\frac{\text{Re}(F(p))}{\sin\epsilon}\int_{\Sigma}\omega\leq\frac{\text{Re}(F(p))}{\sin\epsilon}A(N+1).

More intrinsically F⁡(p)F(p) defines the complex valued volume form Ω~L0\tilde{\Omega}_{L_{0}} on the moduli space, hence

|Im​∫Σe−i​θ^​F​ω|≤1sin⁡ϵ​A​(N+1)​Re​(Ω~L0).|\text{Im}\int_{\Sigma}e^{-i\hat{\theta}}F\omega|\leq\frac{1}{\sin\epsilon}A(N+1)\text{Re}(\tilde{\Omega}_{L_{0}}). (46)

The other two terms in (39) are rewritten as a sum of contributions from intersection points in (38). As in Prop. 3.41, we consider holomorphic polygons whose boundary ∂Σ\partial\Sigma encounters in the clockwise order pN−1∈C​F1​(LN,LN−1),…p_{N-1}\in CF^{1}(L_{N},L_{N-1}),\ldots, p1∈C​F1​(L2,L1)p_{1}\in CF^{1}(L_{2},L_{1}), p=p0∈C​F0​(L1,L0)p=p_{0}\in CF^{0}(L_{1},L_{0}), q=pN∈C​F0​(L0,LN)q=p_{N}\in CF^{0}(L_{0},L_{N}) juxaposed possibly by more degree one self intersections bib_{i} of LiL_{i}. (The other cases, where ∂Σ\partial\Sigma misses some Lagrangians, can be handled completely similarly.) We first deal with these extra self intersections. Using the wedge region bound, and the Novikov positivity requirement,

|Im​∑i∑bie−i​θ^​F​fLi|−+​(bi)|≤∑i∑bi|F⁡(bi)|​fLi|−+​(bi)≤Re​(F​(p))sin⁡ϵ​∑i∑bifLi|−+​(bi).|\text{Im}\sum_{i}\sum_{b_{i}}e^{-i\hat{\theta}}Ff_{L_{i}}|^{+}_{-}(b_{i})|\leq\sum_{i}\sum_{b_{i}}|F(b_{i})|f_{L_{i}}|^{+}_{-}(b_{i})\leq\frac{\text{Re}(F(p))}{\sin\epsilon}\sum_{i}\sum_{b_{i}}f_{L_{i}}|^{+}_{-}(b_{i}).

By Lemma 3.41, we have

|Im​∑i∑bie−i​θ^​F​fLi|−+​(bi)|≤1sin⁡ϵ​A​(N+1)​Re​(Ω~L0).|\text{Im}\sum_{i}\sum_{b_{i}}e^{-i\hat{\theta}}Ff_{L_{i}}|^{+}_{-}(b_{i})|\leq\frac{1}{\sin\epsilon}A(N+1)\text{Re}(\tilde{\Omega}_{L_{0}}). (47)

We are left with the contributions of p0,p1,…​pNp_{0},p_{1},\ldots p_{N} to (38):

Im​∑0N−1e−i​θ^​F​(fLj+1−fLj)​(pj).\text{Im}\sum_{0}^{N-1}e^{-i\hat{\theta}}F(f_{L_{j+1}}-f_{L_{j}})(p_{j}).

If we replace fLif_{L_{i}} by its supremum value supLifLi\sup_{L_{i}}f_{L_{i}} for all i=0,1,…​Ni=0,1,\ldots N, the new expression would be

Im​∑0N−1e−i​θ^​F​(pj)​(supfLj+1−supfLj)=Im​∑1Ne−i​θ^​supfLj​(F⁡(pj−1)−F⁡(pj))−Im​(e−i​θ^​F​(p)​supfL0)\begin{split}&\text{Im}\sum_{0}^{N-1}e^{-i\hat{\theta}}F(p_{j})(\sup f_{L_{j+1}}-\sup f_{L_{j}})\\ =&\text{Im}\sum_{1}^{N}e^{-i\hat{\theta}}\sup f_{L_{j}}(F(p_{j-1})-F(p_{j}))-\text{Im}(e^{-i\hat{\theta}}F(p)\sup f_{L_{0}})\end{split}

which is more intrinsically the integrand (45) of the elementary functional. Using the potential clustering assumption and the wedge region bound lemma, the error of replacing the potentials by supLjfLj\sup_{L_{j}}f_{L_{j}} can be bounded by

2​A​∑1N|F⁡(pj)|≤2​A​N​Re​(F​(p))sin⁡ϵ=2​A​Nsin⁡ϵ​Re​(Ω~L0).2A\sum_{1}^{N}|F(p_{j})|\leq 2AN\frac{\text{Re}(F(p))}{\sin\epsilon}=\frac{2AN}{\sin\epsilon}\text{Re}(\tilde{\Omega}_{L_{0}}). (48)

Now (46)(47)(48) are upper bounds on the three contributions to the difference between the Solomon functional integrand (39) and the elementary functional integrand. Their sum is bounded by

A⁡(4​N+2)sin⁡ϵ​Re​(Ω~L0),\frac{A(4N+2)}{\sin\epsilon}\text{Re}(\tilde{\Omega}_{L_{0}}),

so after integration on the moduli space,

|𝒮⁡(L)−𝒮¯​(L)|≤A⁡(4​N+2)sin⁡ϵ​∫L0Re ​Ω|\mathcal{S}(L)-\bar{\mathcal{S}}(L)|\leq\frac{A(4N+2)}{\sin\epsilon}\int_{L_{0}}\text{Re }\Omega

as required. ∎

Original mathematics by the credited authors. Source-backed reader collection; mathematical self-containment is not assessed.