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Planetarium - Interactive star map and virtual sky. How Quantum Suicide Works&. ­­A man sits down before a gun, which is pointed at his head. This is no ordinary gun; i­t's rigged to a machine that measures the spin of a quantum particle.

Each time the trigger is pulled, the spin of the quantum particle -- or quark -- is measured. Depending on the measurement, the gun will either fire, or it won't. If the quantum particle is measured as spinning in a clockwise motion, the gun will fire. Nervously, the man takes a breath and pulls the trigger. Go back in time to the beginning of the experiment. But, wait. This thought experiment is called quantum suicide. The Elegant Universe: Pt 1. The Elegant Universe: Part 3 PBS Airdate: November 4, 2003 NARRATOR: Now, on NOVA, take a thrill ride into a world stranger than science fiction, where you play the game by breaking some rules, where a new view of the universe pushes you beyond the limits of your wildest imagination.

This is the world of "string theory," a way of describing every force and all matter from an atom to earth, to the end of the galaxies—from the birth of time to its final tick, in a single theory, a "Theory of Everything. " Our guide to this brave new world is Brian Greene, the bestselling author and physicist. BRIAN GREENE (Columbia University): And no matter how many times I come here, I never seem to get used to it. NARRATOR: Can he help us solve the greatest puzzle of modern physics—that our understanding of the universe is based on two sets of laws that don't agree? NARRATOR: Resolving that contradiction eluded even Einstein, who made it his final quest. S. BRIAN GREENE:The atmosphere was electric. S. S. Atomic Test Effects in the Nevada Test Site Region.

Thirty-one atomic fission weapons, weapon prototypes, or experimental devices were fired in Nevada from January 1951 to January 1955. All were relatively small in explosive power. They ranged from less than one kiloton up to considerably less than 100 kilotons. (A kiloton is equal to 1,000 tons of TNT.) The forces released by test detonations in Nevada are very small compared to the tremendous forces released by the large fission and hydrogen weapons tested in the Pacific. Despite their relatively low yield, Nevada tests have clearly demonstrated their value to all national atomic weapons programs. Each Nevada test has successfully added to scientific knowledge needed for development and for use of atomic weapons, and needed to strengthen our defense against enemy weapons. Staging of some tests in Nevada, instead of carrying out all of them in the distant Pacific, also resulted in major savings in time, the most important factor, and in manpower, and money.

Exposure to Flash The U. Einstein Exhibit -- Voice of Einstein. TOP TEN UNSOLVED PROBLEMS IN PHYSICS. Imagining the Tenth Dimension - A Book by Rob Bryanton.