Frontiers/Controversies in Astrophysics (ASTR 160)
This lecture introduces an important concept related to the past and future of the universe: the Scale factor, which is a function of time. With reference to a graph whose coordinates are the Scale factor and time, the problem of dark matter is addressed again. Cosmological redshifts are measured to determine the scale of the universe. The discovery of the repulsive, anti-gravitational force of dark energy is explained. The lecture concludes with discussion of Einstein's biggest mistake: the invention of the cosmological constant to balance gravity.
00:00 - Chapter 1. The Scale Factor
04:41 - Chapter 2. Accounting for Dark Matter in Mass of Universe
27:58 - Chapter 3. Discovery of Dark Energy
42:06 - Chapter 4. Understanding Dark Energy and Einstein's Biggest Mistake
Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses
This course was recorded in Spring 2007.
Tagged under: anti-gravity,constant,cosmological,redshift,critical,density,dark,energy,matter,distance,modulus,Hubble,luminosity,normalizing,Omega,scale,factor,standard,candle,Type,Ia,Supernova,vacuum
Clip makes it super easy to turn any public video into a formative assessment activity in your classroom.
Add multiple choice quizzes, questions and browse hundreds of approved, video lesson ideas for Clip
Make YouTube one of your teaching aids - Works perfectly with lesson micro-teaching plans
1. Students enter a simple code
2. You play the video
3. The students comment
4. You review and reflect
* Whiteboard required for teacher-paced activities
With four apps, each designed around existing classroom activities, Spiral gives you the power to do formative assessment with anything you teach.
Carry out a quickfire formative assessment to see what the whole class is thinking
Create interactive presentations to spark creativity in class
Student teams can create and share collaborative presentations from linked devices
Turn any public video into a live chat with questions and quizzes