---
date: 2022-04-23 02:27
modification date: Saturday 23rd April 2022 02:27:23
title: "Picard Lefchetz theory"
aliases: ["Picard-Lefchetz", "Picard-Lefchetz theory"]
---

Last modified date: <%+ tp.file.last_modified_date() %>

---
- Tags: 
	- #todo/untagged
- Refs:
	- #todo/add-references
- Links:
	- [Lagrangian Floer homology](Unsorted/Lagrangian%20Floer%20homology.md)
	- [unipotent](Unsorted/unipotent.md)
	- [degeneration](Unsorted/degeneration.md)
	- [Sectional curvature](Sectional%20curvature)

---

# Picard Lefchetz theory

![](attachments/Pasted%20image%2020220430151706.png)

![](attachments/Pasted%20image%2020220423022724.png)
![](attachments/Pasted%20image%2020220423022744.png)



# Analogy with Morse theory

See [Morse Theory](Unsorted/Morse%20Theory.md):
![](attachments/Pasted%20image%2020220430182538.png)


Modern perspective via [symplectic](Unsorted/symplectic.md) manifolds:
![](attachments/Pasted%20image%2020220430182706.png)

# Local Monodromy Theorem

![](attachments/2023-03-08monodromy.png)