FABRIC of COSMOS

http://www.pbs.org/wgbh/nova/physics/fabric-of-cosmos.html

Acclaimed physicist Brian Greene reveals a mind-boggling reality beneath the surface of our everyday world.

"The Fabric of the Cosmos," a four-hour series based on the book by renowned physicist and author Brian Greene, takes us to the frontiers of physics to see how scientists are piecing together the most complete picture yet of space, time, and the universe.

Airing 11/2, 11/9, 11/16 and 11/23 on PBS
What is Space?
The Illusion of Time
Quantum Leap
Universe or Multiverse?

[I get this via PBS channel #388 (at SHAW DIRECT SATELLITE) WNED Buffalo-Toronto]


Quick Summary of Part 1: What is Space?

Empty space is not nothing; it is something, it has properties, e.g., it can twist.

Newton's space: a passive framework like the stage used for a play; space is a real, physical thing.

Einstein: the nature of light - constant speed of light is 671 million mph; think of a car with headlights on - the speed of its light coming at you when stopped is same as when car approaches you at 40 mph because light can't go any faster. The speed of light is absolute.

Einstein: nature of gravity - spacetime can stretch and bend like a rubber sheet; it is dynamic and flexible; gravity IS the shape of spacetime.

In 1950's Leonard Schiff conceived a project to test general relativity using orbiting gyroscopes: Gravity Probe B. The idea is to measure how space and time are "warped" by the presence of the Earth. See http://en.wikipedia.org/wiki/Gravity_Probe_B

Quantum Mechanics: empty space is full of activity - particles pop into and out of existence and empty space has enough force to push on matter.

Peter Higgs - Univ. Edinburgh - the Higgs field was proposed by Higgs and others to provide mass to particles. http://en.wikipedia.org/wiki/Peter_Higgs

Big Bang was 14 billion years ago - will the universe continue to expand or will it collapse?

Saul Perlmutter investigated supernovae and discovered that the universe's expansion is accelerating. Something is counteracting the pull of gravity. "Dark energy" has been proposed as the cause. [Fun note: Perlmutter was mentioned recently on a The Big Bang Theory episode in which Sheldon wants to go to a lecture given by Perlmutter just so he can debunk the Nobel laureate's theories publicly.]

Einstein's cosmological constant Λ was introduced to allow for a static universe. He later called it his biggest blunder. The strange thing is: recent improved astronomical techniques have found that a positive value of Λ is needed to explain the accelerating universe.

The strangest revelation (revelation or crazy idea?) in "Part 1: What is Space?" is this:

* when something falls into a black hole it is lost forever; at least, the 3D version of that something; BUT the 2D version (information about the thing) stays at the black hole's surface

* imagine reality as a hologram -- with the 3D part = things in the universe and the 2D part = the surface of the universe.

I'm excited about the next episode: The Illusion of Time