Update week4.do.txt

Author: mhjensen

doc/src/week4/week4.do.txt

@@ -42,7 +42,7 @@ physical processes.
 !split
 ===== Structure of the lecture =====
 
-o First we review some of the basic ways of representing the solution to the Schrödinger equation, introducing the so-called Interaction, Heisenberg and Schrödinger prictures and unitary transformations.
+o First we review some of the basic ways of representing the solution to the Schrödinger equation, introducing the so-called Interaction, Heisenberg and Schrödinger prictures and unitary transformations. These material is meant mainly as background material
 o Secondly, we present examples of physical processes and how they can be represented as unitary operations on a given state.
 o These unitary transformations are then represented as gates. Setting gates together gives us a final circuit which can represent a specific physical system
 
@@ -636,9 +636,6 @@ Using this result, we obtain
 \]
 !et
 
-The whiteboard notes for this week contain other examples of one qubit gates and their relation to specific unitary transformations and effective Hamiltonian, see URL:"https://github.com/CompPhysics/QuantumComputingMachineLearning/blob/gh-pages/doc/HandWrittenNotes/2025/NotesFebruary12.pdf"
-
-# material to be added
 
 !split
 ===== Part 3: Famous Quantum gates, circuits and simple algorithms (repetition  from last week) =====