fixed a typo

thesis/chapters/quantum_computing.tex

@@ -144,9 +144,9 @@ matrices to the basis states)
     be a  $n$ qbit state
     where $\ket{1}_j, \ket{0}_j$ denote the $j$-th qbit state and $|\alpha|^2 + |\beta|^2 = 1$. 
     Then the measurement of the $j$-th qbit will yield 
-    $$\ket{\phi_1} \otimes \ket{1}_n$$ 
+    $$\ket{\phi_1} \otimes \ket{1}_j$$ 
     with probability $|\alpha|^2$ and 
-    $$\ket{\phi_0} \otimes \ket{0}_n$$
+    $$\ket{\phi_0} \otimes \ket{0}_j$$
     with probability $|\beta|^2$.  This is called collapse of the wave function.
 \end{postulate}