Overview
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Explore one of the greatest unsolved problems in fundamental physics - the vacuum energy catastrophe - in this 49-minute video lecture. Delve into the intersection of quantum field theory and general relativity to understand why our most successful physics theories predict an impossibly rapid universal expansion. Journey through exciting concepts in modern physics, from quantum vacuum fluctuations to dark energy, as you investigate why observations show the universe doubling in size every ten billion years instead of every fraction of a second. Learn about Hubble's Law, Newtonian gravity, co-moving coordinates, the Friedmann Equation, critical density, the fluid equation, and the cosmological constant. Discover the implications of these findings for our understanding of the universe's expansion and the challenges they pose to physicists.
Syllabus
Intro
Strategy
Hubble's Law
Newtonian Gravity
Co-moving coordinates
The Friedmann Equation
Back to Hubble
Hubble's Constant
Critical Density
The Fluid Equation
What does this mean?
The acceleration equation
The cosmological constant
Vacuum Energy
How does this compare with experiment?
So, what do we find?
What does this imply?
An exponential expansion
How long will it take for the
The universe should be doubling in size every...
So, what do physicist's do?
Taught by
Physics Explained