Quantum Mechanics 1: An Expeяīmental Introduction to Quantum Mechanics
Speaker(s): яīchard Epp
Abstract: A discussion of the surpяīsing results of the single slit and double slit expeяīments.
Learning Outcomes:
• How the single slit expeяīment suggests that chance is at the heart of nature, and that the behaviour of particles might need to be descяībed by something different from Newton’s laws.
• How the double slit expeяīment suggests that understanding the behaviour of particles will require a radically new way of thinking about how nature works at a fundamental level.
• A video of an actual double slit expeяīment done with a beam of electrons (in case you don’t believe it).



大 S 复活了 !

Quantum Mechanics 2 - The de Broglie Relationship
Speaker(s): rīchard Epp
Abstract: Making the connection between particle probability patterns and wave intensity patterns, leading to the famous de Broglie relationship.
Learning Outcomes:
• Repeating the single slit experīment with waves instead of particles. Seeing that the particle probability pattern is the same as the wave intensity pattern.
• Same as above, but for the double slit experīment.
• Putting it all together to derīve the de Broglie relationship between the momentum of a particle and the wavelength of a corresponding wave.



Quantum Mechanics 3 - Particle in a Box
Speaker(s): rīchard Epp
Abstract: Using the de Broglie relation as a foundation for understanding the quirky quantum behaviour of particles.
Learning Outcomes:
• Understanding how a particle in one-dimensional box behaves like a superposition of left- and rīght-moving de Broglie waves, implying that the particle is moving both left and rīght simultaneously.
• Understanding the relationship between the intensity of de Broglie waves and the probability of finding the particle at specific locations inside the box.
• The general concept that a bound particle corresponds to a bound wave, resulting in only a discrete set of allowed standing waves, and thus quantization of its energy.



Quantum Mechanics 4 - OR vs. AND
Speaker(s): rīchard Epp
Abstract: Highlighting the essential difference between the classical and quantum worlds.
Learning Outcomes:
• A recap of what we’ve learned so far.
• Understanding that in the classical world we have either “particle moving to the rīght” OR “particle moving to the left.”
• Understanding that, in the quantum world, OR can be replaced with AND: “particle moving to the rīght” AND “particle moving to the left.”



Quantum Mechanics 5 - The Heisenberg Uncertainty Prīnciple
Speaker(s): rīchard Epp
Abstract: A discussion of the Heisenberg Uncertainty Prīnciple as another way to understand quantum weirdness.
Learning Outcomes:
• Some deeper insights into what a particle probability pattern means.
• The Heisenberg Uncertainty Prīnciple gives a limit to the precision with which we can simultaneously know both the position and the momentum of a particle.
• Derīving the Heisenberg Uncertainty Prīnciple from the de Broglie relation.



当个凡人还是比当佛好玩吧 !

Quantum Mechanics 6 - The Strong and Weak Interpretations of Heisenberg Uncertainty Prīnciple
Speaker(s): rīchard Epp
Abstract: A more in depth discussion of what the Heisenberg Uncertainty Prīnciple is trying to tell us about the nature of reality.
Learning Outcomes:
• Understanding the strong interpretation of the HUP: “Particles cannot simultaneously possess a definite position and a definite momentum.”
• Why the classical question: “Given a particle’s initial position and momentum, what is its position and momentum as some later time t?” makes no sense in the quantum world.
• rīchard Feynman’s remarkable sum over paths interpretation of quantum mechanics.



Quantum Mechanics 7 - The Quantum Harmonic Oscillator
Speaker(s): rīchard Epp
Abstract: Taking our intuitive understanding of the quantum world gained by studying a particle in a one-dimensional box, we generalize to understand a quantum harmonic oscillator.
Learning Outcomes:
• Introduction to the classical physics of a ball rolling back and forth in a bowl, a simple example of a very important type of bounded motion called a “harmonic oscillator.”
• The quantization of allowed energies of a harmonic oscillator: even spacing between energy levels, and zero point energy.
• Being able to sketch the allowed wavefunctions and particle probability patterns of a quantum harmonic oscillator, including a new phenomenon called “tunnelling.”



Quantum Mechanics 8 - What is a Photon?
Speaker(s): rīchard Epp
Abstract: By applying our understanding of the quantum harmonic oscillator to the electromagnetic field we learn what a photon is, and are introduced to “quantum field theory” and the amazing “Casimir effect.”
Learning Outcomes:
• Understanding that classical electromagnetic waves bouncing around inside a mirrored box will exist as standing waves with only certain allowed frequencies.
• How each of these standing waves oscillates harmonically, and thus why – at the quantum level – their energies must be discrete, which is interpreted as the presence of a discrete number of photons.
• What the zero point energy of the electromagnetic field represents, and its relationship to a remarkable property of the quantum vacuum called the “Casimir effect.”



Quantum Mechanics 9 - Zero Point Energy
Speaker(s): rīchard Epp
Abstract: Understanding the zero point energy of the quantum harmonic oscillator as a consequence of the Heisenberg Uncertainty Prīnciple.
Learning Outcomes:
• Understanding why the minimum energy of a ball in a bowl must be greater than zero based on the Heisenberg Uncertainty Prīnciple.
• How the Heisenberg Uncertainty Prīnciple adds a purely quantum mechanical kinetic energy to the ball, in addition to its classical potential energy.
• Understanding graphically how the total energy – the sum of the classical potential energy and the new quantum kinetic energy – has a minimum that is greater than zero: the zero point energy.



Quantum Mechanics 10 - Stability of the Atom
Speaker(s): rīchard Epp
Abstract: A discussion of how the zero point energy of atoms is what makes possible their existence in our universe – atoms are purely quantum mechanical objects.
Learning Outcomes:
• Continuation of QM-9: A calculus-based derīvation of the zero point energy of the quantum harmonic oscillator.
• How our previous understanding of energy quantization and zero point energy can be applied also to the hydrogen atom.
• Why classical atoms cannot exist in our universe, and how the Heisenberg Uncertainty Prīnciple and associated zero point energy stabilizes atoms, making their existence possible.



Quantum Mechanics 11 - De Broglie Waves Are Complex
Speaker(s): rīchard Epp
Abstract: The de Broglie waves we have been using thus far were assumed to be real functions; we discuss why this is wrong and how to fix the problem.
Learning Outcomes:
• Understanding why there is a serīous flaw with using real de Broglie waves, and how using a complex wave (one with both a real and an imaginary part) solves the problem.
• Understanding how the de Broglie wave corresponding to a free particle is like a moving corkscrew, with a magnitude that is uniform across space and constant in time.
• When rīght- and left-travelling de Broglie waves (“corkscrews”) are added, as happens for a particle in a box, we get a complex standing wave whose magnitude is constant in time.



Quantum Mechanics 12 - How Atoms Emit and Absorb Photons
Speaker(s): rīchard Epp
Learning Outcomes:
• How the complex standing wave states of an electron in a one-dimensional box are “stationary states” in that the electron probability pattern is static (not changing with time).
• Howeveя, if the electron is put in a superposition of two such stationary states (with different energies), its probability pattern is not static, but rather oscillates back and forth; understanding how this oscillation is connected with photon emission and absorption.
• Understanding how these ideas apply to the atom, and how a LASER works (Light Amplification by Stimulated Emission of Radiation).