Uploaded June 2025 | Updated September 2026, 1 day ago
đ Lesson 18 of 21
â¶ïž Watch the full lecture series here: youtube.com/playlist?list=PLIGRVb_-L3Eokg9bMKOX6XLyVgxlPb8uv
What happens when you measure a quantum system?
In this lesson, we explore the deep connection between a system's expansion coefficients and the outcomes of energy measurements. You'll learn how the squared moduli of these coefficients determine the probabilities of different measurement resultsâand why these probabilities matter. We introduce the concept of wave function collapse, the dramatic transformation of a quantum state into a definite energy eigenstate upon measurement. This lesson ties the mathematics of superposition to the physical process of observation, bridging abstract theory with experimental reality.
đ Solved exercises for this course are available here: quantphys.com/lessons/qm1
đ Lesson 18 of 21
â¶ïž Watch the full lecture series here: youtube.com/playlist?list=PLIGRVb_-L3Eokg9bMKOX6XLyVgxlPb8uv
What happens when you measure a quantum system?
In this lesson, we explore the deep connection between a system's expansion coefficients and the outcomes of energy measurements. You'll learn how the squared moduli of these coefficients determine the probabilities of different measurement resultsâand why these probabilities matter. We introduce the concept of wave function collapse, the dramatic transformation of a quantum state into a definite energy eigenstate upon measurement. This lesson ties the mathematics of superposition to the physical process of observation, bridging abstract theory with experimental reality.
đ Solved exercises for this course are available here: quantphys.com/lessons/qm1
![Quantum Fractals [QBE Ep. 3]](https://i.ytimg.com/vi/_iHbpTirOS4/mqdefault.jpg "Quantum Fractals [QBE Ep. 3]
Episode 3 of Quantum on the Back of an Envelope [QBE].
đ Watch the full series here: https://www.youtube.com/playlist?list=PLIGRVb L3EpDzApE5EnAOYyTAyagvi1W
In this episode of Quantum on the Back of an Envelope, we explore quantum fractals through one of the simplest quantum-mechanical systems: the particle in a box. The fractal wave function discussed here is based on the paper: M. V. Berry, Quantum fractals in boxes, J. Phys. A: Math. Gen. 29, 6617 (1996).")
