Ch07 lecture
- 1. Albert Einstein and the Theory of Relativity Chapter 7 Great Idea: All observers, no matter what their frame of reference, see the same laws of nature
- 2. Chapter Outline • Frames of Reference • Special Relativity • General Relativity
- 4. Descriptions in Different Reference Frames • Coin’s path appears different depending on your frame of reference
- 5. The Principle of Relativity • Baseball vs. Light • Einstein’s solution: – The laws of nature are not the same in all frames of reference – Maxwell’s equation could be wrong – Our intuitions about the addition of velocities could be wrong • Principle of Relativity – Every observer must experience the same natural laws • Special relativity • General relativity • The speed of light, c, is the same in all reference frames
- 7. Time Dilation • Time Dilation – Moving clock appears to tick more slowly
- 8. The Size of Time Dilation • Calculation of time dilation – tGG=tMM – Stationary ground-based observer • tGG=d/c • Distance traveled by light in 1 tick
- 9. Distance and Relativity • Length Contraction – Moving object appears shorter
- 10. So What About the Train and the Flashlight? • Addition of velocities – Valid at small velocities – Not valid near speed of light
- 11. Mass and Relativity • Third consequence – Mass is lowest for stationary objects • Conclusions: – Nothing moving less than speed of light can be accelerated to or past c – Object above c cannot be decelerated – Objects at c have zero rest mass
- 12. Mass and Energy • Einstein – All objects contain a rest energy E = mc 2 – Mass can be converted to energy and vice versa
- 14. The Nature of Forces • Gravitational forces and acceleration – Frame of reference
- 15. The Nature of Forces • Newton vs. Einstein
- 16. Predictions of General Relativity • The gravitational bending of light • Planetary orbits • The gravitational redshift
- 17. Who Can Understand Relativity? Everyone!!