PBS has made available online three NOVA programs on unified theory. Watch the second of these titled "String's the Things". The video is separated into 8 chapters. Hint: After you have watched Chapter 1 that is 8 minutes and 26 seconds long hit the "PLAY NEXT CHAPTER" button at the top of the video window.

Answer any 5 of the questions below and hit "Submit". You can answer more than 5 if you are uncertain about your answers.

1. What theory seems to unite the laws of quantum mechanics and gravity?

2. What it the name of the theory that explains large scale phenomena?

3. What is the name of the particle that String Theory predicts to travel faster than light?

4. How does general relativity explain gravity?

5. What do some string theorist think the "mysterious massless particle" really is?

6. How many different version of string theory did physicists develop in the 1980s?

7. What is the name of the particle that is used to describe gravity?