19. Omega and the End of the Universe
Μεταφορτώθηκε στις 29 Σεπ 2008
Frontiers/Controversies in Astrophysics (ASTR 160)
Class
begins with a review of the issues previously addressed about the
origin and fate of the universe. The role of gravity in the expansion of
the universe is discussed and given as the reason why the rate of
expansion cannot remain constant and will eventually slow down. The
actual density of the universe is calculated using various methods.
Finally, the unsolved problem of dark matter is addressed and two
explanatory hypotheses are proposed. One is that the universe is
comprised of WIMPs (Weakly Interactive Massive Particles) that fulfill
two requirements: they have mass and do not interact with light. The
second hypothesis is that dark matter is made of MACHOs (Massive
Astrophysical Compact Halo Objects), which scientists have attempted to
identify through gravitational lenses.
00:00 - Chapter 1. Review of Issues in Cosmology
08:28 - Chapter 2. Determining Mass
26:39 - Chapter 3. Dark Matter: WIMPs?
37:30 - Chapter 4. Dark Matter: MACHOs?
Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses
This course was recorded in Spring 2007.
Class
begins with a review of the issues previously addressed about the
origin and fate of the universe. The role of gravity in the expansion of
the universe is discussed and given as the reason why the rate of
expansion cannot remain constant and will eventually slow down. The
actual density of the universe is calculated using various methods.
Finally, the unsolved problem of dark matter is addressed and two
explanatory hypotheses are proposed. One is that the universe is
comprised of WIMPs (Weakly Interactive Massive Particles) that fulfill
two requirements: they have mass and do not interact with light. The
second hypothesis is that dark matter is made of MACHOs (Massive
Astrophysical Compact Halo Objects), which scientists have attempted to
identify through gravitational lenses.
00:00 - Chapter 1. Review of Issues in Cosmology
08:28 - Chapter 2. Determining Mass
26:39 - Chapter 3. Dark Matter: WIMPs?
37:30 - Chapter 4. Dark Matter: MACHOs?
Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses
This course was recorded in Spring 2007.
ΑΝΑΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 20/3/2014
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