Pure vs. mixed quantum states

📚 Probability arises in quantum mechanics every time we perform a measurement. However, probability also features more generally in science to describe systems for which we only have partial information. In this video, we consider what happens when we have a system for which we only have partial information, but this system is a quantum system. In these cases, we need to consider both types of probability, and to do so we use pure states and mixed states.

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⏮️ BACKGROUND
Measurements | Concepts:    • Measurements in quantum mechanics || Concepts  
Measurements | Maths:    • Measurements in quantum mechanics || Mathe...  
State collapse:    • State collapse in quantum mechanics  

⏭️ WHAT NEXT?
Density operator for pure states:    • Density operator for pure quantum states  
Density operator for mixed states:    • Density operator for mixed quantum states  

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Director and writer: BM
Producer and designer: