Update class12.md

Author: Pedro Paulo

.DS_Store

@@ -4,7 +4,16 @@
 
 **Topic:** Neural operators (FNO, Galerkin Transformer); large-scale surrogates
 
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+**📘 Class 03 Topics**
+- **Foundations of Neural Operators** - Function-to-function learning beyond finite dimensions.
+- **Fourier Neural Operator (FNO)** - FFTs for PDE solutions
+- **Galerkin Transformer** - Attention with Galerkin projection for PDEs.
+- **Applications** - Biomedical, climate, fluids, materials, and research directions.
 
-Add notes, links, and resources below.
+**📚 Useful References**
+- 📖 Z. Li *et. al.*: FOURIER NEURAL OPERATOR FORPARAMETRIC PARTIAL DIFFERENTIAL EQUATIONS (Available at: https://arxiv.org/abs/2010.08895)
+- 📖 S. Cao: Choose a Transformer: Fourier or Galerkin (Available at: https://arxiv.org/abs/2105.14995)
+- 📖 Z. Li *et. al.*: Transformer for Partial Differential Equations’
+Operator Learning (Available at: https://arxiv.org/pdf/2205.13671)
+- 📖 J. Koch *et. al.*: Learning Neural Differential Algebraic Equations via Operator Splitting (Available at: https://arxiv.org/abs/2403.12938)