diff --git a/README.md b/README.md
index 7e305e0..20ae43f 100644
--- a/README.md
+++ b/README.md
@@ -250,6 +250,11 @@ Ramanujan's deep insights into infinite series and modular forms continue to inf
    [Where]():  
      - **\( E \)**: Energy of a state.  
      - **\( \mu \)**: Chemical potential.  
+     - **\( k_B \)**: Boltzmann constant.  
+    
+   
+
+