Class #17 (Mar. 4) Reading Questions - The Fabric of the Cosmos

Chapter 6

1. What is time reversal symmetry and why do interplanetary tennis balls obey this while dropped eggs don't?

2. What is entropy and how does Greene use one of my favorite novels to illustrate this concept?

3. What is the second law of thermodynamics and how does this law lead to a "quagmire" when we apply it to the past?

4. How can cosmology get us out of the second law quagmire?

Chapter 7

5. Explain the beam splitter interference experiment and the conceptual difficulty it raises when operated one photon at a time.

6. Describe Wheeler's delayed choice experiment and explain how this experiment raises the question: "does the past depend on the future?".

7. What is a quantum eraser and can we use one to change the past?

8. Does quantum mechanics set an arrow of time?

Your Question: Please give a well formulated question that you have regarding the material covered in this reading assignment.