Tom's troublesome edit of the new asset pricing lecture

Author: thomassargent30

lectures/asset_pricing_lph.md

@@ -1,4 +1,4 @@
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+z---
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-## Elementary asset pricing theory
+# Elementary Asset Pricing Theory
+
+
+```{index} single: Elementary Asset Pricing
+```
 
+```{contents} Contents
+:depth: 2
+```
 
-This lecture summarize the heart of applied asset-pricing theory.
+This lecture summarizes the heart of applied asset-pricing theory.
 
 From a single equation, we'll derive 
 
@@ -30,6 +37,11 @@ To do this, we use two ideas:
 
   * a Cauchy-Schwartz inequality
 
+
+For background and basic  concepts, see our lecture [orthogonal projections and their applications](https://python-advanced.quantecon.org/orth_proj.html).
+
+As a sequel to the material here, please see our lecture [two modifications of mean-variance portfolio theory](https://python-advanced.quantecon.org/black_litterman.html).
+
 We  begin with a **key asset pricing equation**: