Syllabus

Lecture 1  Dawn of New Age I (Harris Chapter 1) (8/24/2026)

The goal of this course is to become familiar with non-classical physics, learn some of the new mathematics needed to describe it, appreciate how surprising many modern-physics discoveries were, and understand how scientific knowledge evolves when an established framework encounters limits. We will begin with a historical example from mechanics and astronomy: Kepler summarized planetary motion empirically, Newton explained it dynamically, the anomaly in Mercury’s orbit exposed a limit of Newtonian gravity, and general relativity provided a broader framework. We will then follow a similar progression in electricity and magnetism, where separate electric and magnetic phenomena were unified, light was identified as an electromagnetic wave, and tensions between electromagnetism and classical mechanics ultimately helped lead to special relativity.
(Extra Recommended Reading Assignment: Read Thomas Kuhn's The Structure of Scientific Revolutions Chapter 1: Role of History)

Lecture 2  Dawn of New Age II (Harris Chapter 1) (8/26/2026)

In Lecture 2, we conclude our discussion of electromagnetism by showing how the electromagnetic wave equation emerges from Maxwell’s equations. We then explore how the constant speed of light, motivated Einstein’s formulation of special relativity. Finally, we examine the failure of classical equipartition to describe heat capacity, where predictions of a constant value break down at low temperatures. This anomaly was resolved by Einstein and Debye, whose quantum vibrational models accurately capture the drop to zero and mark an early milestone of quantum theory. 

(Review Maxwell's equations, Specific heat of diamond )

Lecture 3  Hollistic view of Modern Physics (Harris Chapter 1) (8/31/2026)

In lecture 3, I will provide a holistic overview of modern physics, detailing the evolution from classical mechanics to quantum mechanics and special relativity. We will also explore how to think about high-energy physics, astrophysics, and condensed matter physics, emphasizing concepts like emergence and the study of extreme energy scales. 

Lecture 4 Black Body Radiation and Ultraviolet Catastrophe (Harris Chapter 2) (9/2/2026)

Starting with Lecture 4, we will focus on a cornerstone of quantum mechanics: wave-particle duality. We will examine how electromagnetic waves can behave like particles by studying blackbody radiation, the failure of the classical prediction, and Planck’s successful description of the spectrum. This introduces Planck’s constant h and the idea of quantized energy.

Lecture 5 Photoelectric Effect and Compton Scattering (Harris Chapter 2) (9/4/2026)

Lecture 5 examines the photoelectric effect and Compton scattering as a more direct evidence of the particle nature of light. The photoelectric effect shows that electrons are emitted only when the light frequency exceeds a threshold, and the kinetic energy depends on the frequency of light. Compton scattering further establishes that photons carry momentum and shows how conservation of energy and momentum leads to the wavelength shift and scattering angle.

Lecture 6 Q&A and Compton Scattering (Harris Chapter 2) (9/9/2026)

In Lecture 6, we'll take a moment to review the excellent questions raised by students. Afterward, I will walk you through the derivation of the Compton scattering formula.

Lecture 7 Q&A and Compton Scattering (Harris Chapter 2) (9/11/2026)

In Lecture 7, we explore when light acts as a wave versus a particle. It behaves like a particle when its wavelength is much smaller than the detector size, and like a wave otherwise. Slit experiments demonstrate that even individual photons build interference patterns over time, proving a particle's probability is directly linked to its wave amplitude.
(See also ai generated notes from Prof. Yongbin Feng)