ScalingStacks

Verified tagged author-source HTML · 2007.01384v1 · cited publication edition alignment unverified.

For fixed ϵ\epsilon, after deleting terms suppressed by order O⁡(1|log⁡|t||)O(\frac{1}{|\log|t||}), we have the asymptote on EJ,tϵ⊂XtE_{J,t}^{\epsilon}\subset X_{t} as t→0t\to 0:

d​dc​u∼∑0p∂2u∂xi​∂xj​1|log⁡|t||2​−14​π​d​log⁡zi∧d​log⁡z¯j+1log⁡|t|​∑I∂u∂xi​d​dc​log⁡ri,dd^{c}u\sim\sum_{0}^{p}\frac{\partial^{2}u}{\partial x_{i}\partial x_{j}}\frac{1}{|\log|t||^{2}}\frac{\sqrt{-1}}{4\pi}d\log z_{i}\wedge d\log\bar{z}_{j}+\frac{1}{\log|t|}\sum_{I}\frac{\partial u}{\partial x_{i}}dd^{c}\log r_{i},

where z0,…​zpz_{0},\ldots z_{p} are the local defining functions of the divisors Ei⊂𝒳E_{i}\subset\mathcal{X}, and EJ=∩0pEiE_{J}=\cap_{0}^{p}E_{i}. Using that t=z0​…​zpt=z_{0}\ldots z_{p} locally around EJE_{J}, we can eliminate the z0z_{0} variable to write

d​dc​u∼∑1p∂2ϕ∂xi​∂xj​1|log⁡|t||2​−14​π​d​log⁡zi∧d​log⁡z¯j+1log⁡|t|​∑I∂u∂xi​d​dc​log⁡ri,dd^{c}u\sim\sum_{1}^{p}\frac{\partial^{2}\phi}{\partial x_{i}\partial x_{j}}\frac{1}{|\log|t||^{2}}\frac{\sqrt{-1}}{4\pi}d\log z_{i}\wedge d\log\bar{z}_{j}+\frac{1}{\log|t|}\sum_{I}\frac{\partial u}{\partial x_{i}}dd^{c}\log r_{i},

hence

−d​dc​log⁡ht1/2∼∑1p∂2ϕ∂xi​∂xj​1|log⁡|t||​−14​π​d​log⁡zi∧d​log⁡z¯j−d​dc​log⁡hℒ1/2−∑I∂u∂xi​d​dc​log⁡ri.\begin{split}-dd^{c}\log h_{t}^{1/2}\sim&\sum_{1}^{p}\frac{\partial^{2}\phi}{\partial x_{i}\partial x_{j}}\frac{1}{|\log|t||}\frac{\sqrt{-1}}{4\pi}d\log z_{i}\wedge d\log\bar{z}_{j}\\ &-dd^{c}\log h_{\mathcal{L}}^{1/2}-\sum_{I}\frac{\partial u}{\partial x_{i}}dd^{c}\log r_{i}.\end{split} (13)

Notice that d​dc​log⁡ri∼−d​dc​ϕidd^{c}\log r_{i}\sim-dd^{c}\phi_{i} has a smooth extension to the central fibre as t→0t\to 0; the singular effect is eliminated by d​dc​log⁡|zi|=0dd^{c}\log|z_{i}|=0 on XtX_{t}. The term ∑1p∂2ϕ∂xi​∂xj​1|log⁡|t||​−14​π​d​log⁡zi∧d​log⁡z¯j\sum_{1}^{p}\frac{\partial^{2}\phi}{\partial x_{i}\partial x_{j}}\frac{1}{|\log|t||}\frac{\sqrt{-1}}{4\pi}d\log z_{i}\wedge d\log\bar{z}_{j} dominates in the directions transverse to EJE_{J}, and the term −d​dc​log⁡hℒ1/2+∑I∂u∂xi​d​dc​ϕi-dd^{c}\log h_{\mathcal{L}}^{1/2}+\sum_{I}\frac{\partial u}{\partial x_{i}}dd^{c}\phi_{i} dominates in the directions tangential to EJE_{J}.

Original mathematics by the credited authors. Source collection and HTML conversion remain in progress.