This is the fourth lecture series of my complete online introductory undergraduate college course. This video series was used at William Paterson University and CUNY Hunter in online classes as well as to supplement in-person course material. Notes and links are present in the videos at the start of each lecture.
0:00:00 - lecture 1: The Nature of Light, part 1
0:27:18 - lecture 2: The Nature of Light, part 2
0:51:05 - lecture 3: Stellar Brightness and Magnitudes
1:16:41 - lecture 4: Color and Temperature
2:00:38 - lecture 5: Kirchhoff's Laws of Spectroscopy
2:05:55 - lecture 6: Atoms, Elements and Isotopes
2:42:26 - lecture 7: The History of the Atom
3:03:31 - lecture 8: The Bohr Model of the Atom
In this lecture series, we start with a two-part discussion on the nature of light and a summary of its wave-like properties. I'll discuss what exactly a photon is, and how it makes up all the colors of the electromagnetic spectrum. Next, I'll define the terms "brightness" and "luminosity", which are central to astronomy measurement. I'll also define the magnitude system, both apparent and absolute. We won't shy away from equations anymore, as I also derive how Pogson saddled all the future of astronomy with a Log-base-10 humbug. In the next lecture, I chat about how we exactly define color in astronomy using broadband filters. I also detail how color relates to temperature, what temperature actually is, and how blackbody radiation manifests in everyday life and in stars. Next up, I talk about how light interacts with matter, using Kirchhoff's Laws. Following this, I discuss the current state of knowledge about atoms, elements and isotopes. I chat about the periodic table, atomic numbers, what an atom is, how big they are, how they interact. Also, you'll learn about radioactivity. Because this is not at all intuitive, it's worth an extended discussion about the origin of the atom from Democritus to Plato and Aristotle to Dalton to Thomson to Rutherford. I'll show you all of the ways our view of matter has evolved, both philosophically and as a result of experiment. Finally, we end with a beginning quantum mechanical discussion. The Bohr Model of the atom is the standard way that introductory astronomy textbooks seek to demonstrate the link between atomic spectra and Kirchhoff's Laws of spectroscopy. It's important to motivate it with the essentials of quantum mechanics. Here, we add in Einstein's and deBroglie's and Schroedinger's contributions, but we lean back towards the "Astro 101" understanding of the atom.
16 май 2024
