PHYSICS
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This book is a continuing work in progress. When I have time, I edit, expand and add to the chapters. For the convenience of readers who need a stable version that will not change, there are archived versions, which are snapshots of the state of the book at the date indicated: For over a decade I have taught an introductory, undergraduate class, "Einstein for Everyone," at the University of Pittsburgh to anyone interested enough to walk through door.
Einstein for Everyone
An Essay by Einstein -- The World As I See It
"How strange is the lot of us mortals! Each of us is here for a brief sojourn; for what purpose he knows not, though he sometimes thinks he senses it. But without deeper reflection one knows from daily life that one exists for other people -- first of all for those upon whose smiles and well-being our own happiness is wholly dependent, and then for the many, unknown to us, to whose destinies we are bound by the ties of sympathy. A hundred times every day I remind myself that my inner and outer life are based on the labors of other men, living and dead, and that I must exert myself in order to give in the same measure as I have received and am still receiving...Personal and Historical Perspectives of Hans Bethe
Three Lectures by Hans Bethe IN 1999, legendary theoretical physicist Hans Bethe delivered three lectures on quantum theory to his neighbors at the Kendal of Ithaca retirement community (near Cornell University). Given by Professor Bethe at age 93, the lectures are presented here as QuickTime videos synchronized with slides of his talking points and archival material. Intended for an audience of Professor Bethe's neighbors at Kendal, the lectures hold appeal for experts and non-experts alike.
Metal Alloy Purifies Water and Generates Electricity | Alternative Energy | Aluminum | InnovationNewsDaily
Forget unobtanium, this stuff is everywhere. Credit: Jerry Woodall At last, little chunks of aluminum everywhere can be something greater then a soda can or a baseball bat.
Crazy!!! Space Nuclear Test - YouTube
Nice. You may also like this. http://thinkonyourown.com/harm/WeaponMakers.html by Dec 16
ENERGY
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Popular histories too often present perpetual motion machines as "freaks and curiosities" of engineering without telling us just how they were understood at the time. They also fail to inform us that even in the earliest history of science and engineering, many persons were able to see the futility and folly of attempts to achieve perpetual motion. Sometimes a particular device comes to us with a label, such as "Bishop Wilkins' magnetic perpetual motion machine."
Despite its incredibly low density, aerogel is one of the most powerful materials on the planet. It can support thousands of times its own weight, block out intense heat, cold and sound – yet it is 1,000 times less dense than glass, nearly as transparent and is composed of %99.8 air. The lowest-density silica-based aerogels are even lighter than air.
Aerogel: See-Through, Strong as Steel & Ligher than Air | Designs & Ideas on Dornob
SPACE