Drosophila 101 Posted April 4, 2011 Optical Transistor Advance: Physicists Rotate Beams of Light With Semiconductor I would love to have laser computer.. how awesome would that be?! OK I have a thing for lasers so I might be biased, but I think it would be rather cool Quote Share this post Link to post Share on other sites
Drosophila 101 Posted April 4, 2011 Search for Advanced Materials Aided by Discovery of Hidden Symmetries in Nature everything is spirals.. hmpf and reversed spirals... Quote Share this post Link to post Share on other sites
Drosophila 101 Posted April 13, 2011 Some Features of Human Face Perception Are Not Uniquely Human, Pigeon Study Shows Quote Share this post Link to post Share on other sites
Drosophila 101 Posted April 15, 2011 This is really amazing stuff, I just went to see a talk with this guy this morning, and it represent a truly mindboggling change in the view of a basic molecule as water http-~~-//www.youtube.com/watch?v=XVBEwn6iWOo Quote Share this post Link to post Share on other sites
LuisBSF 26 Posted April 15, 2011 http://documentaryheaven.com/the-mystery-of-empty-space/ Extremely interesting talk on what's really going on on "empty" space, gravity, the higgs boson. Quote Share this post Link to post Share on other sites
Rotwang 323 Posted April 17, 2011 Artificial photosynthesis Also this Quote Share this post Link to post Share on other sites
sickdogs 2 Posted April 19, 2011 http://www.youtube.com/watch?v=Y-P1zZAcPuw Forget light and laser shows, I want holographic patterns and objects projected above my head at parties Quote Share this post Link to post Share on other sites
needle ninja 13 Posted April 21, 2011 http-~~-//www.youtube.com/watch?v=Y-P1zZAcPuw Forget light and laser shows, I want holographic patterns and objects projected above my head at parties The Japanese are always trying to make the next great video game expirience! Quote Share this post Link to post Share on other sites
Drosophila 101 Posted April 26, 2011 We are One of a Vast Universe of New Universes Constantly Being Created " --MIT Physicist Quote Share this post Link to post Share on other sites
Drosophila 101 Posted May 13, 2011 Can NASA's Kepler Space Telescope Identify ET Astro-Engineering Artifacts? Quote Share this post Link to post Share on other sites
needle ninja 13 Posted May 19, 2011 Can NASA's Kepler Space Telescope Identify ET Astro-Engineering Artifacts? Broken link Quote Share this post Link to post Share on other sites
Rotwang 323 Posted May 24, 2011 Amazonian tribe suggests knowledge of geometry is innate Quote Share this post Link to post Share on other sites
Drosophila 101 Posted July 8, 2011 Broken link Can NASA's Kepler Space Telescope Identify ET Astro-Engineering Artifacts? fixed Quote Share this post Link to post Share on other sites
Drosophila 101 Posted July 9, 2011 Is the Universe Spinning? New Research Says "Yes" Quote Share this post Link to post Share on other sites
Drosophila 101 Posted July 15, 2011 Are We Living in a Holographic Universe? This May Be the Greatest Revolution of the 21st Century wow,,, trippish! Quote Share this post Link to post Share on other sites
Veracohr 106 Posted July 16, 2011 Are We Living in a Holographic Universe? This May Be the Greatest Revolution of the 21st Century wow,,, trippish! +1 Quote Share this post Link to post Share on other sites
Charlie 2 Posted August 10, 2011 Is the Universe Spinning? New Research Says "Yes" That's pretty weird if it's true. Isn't matter supposed to spin as it contracts, not as it expands? Quote Share this post Link to post Share on other sites
karan129 2 Posted August 10, 2011 Report on using antimatter orbiting the Earth and Saturn to fuel rockets. http://www.niac.usra.edu/files/studies/final_report/1071Bickford.pdf This has to be one of the coolest ideas I've come across in awhile. Quote Share this post Link to post Share on other sites
Rotwang 323 Posted August 10, 2011 That's pretty weird if it's true. Isn't matter supposed to spin as it contracts, not as it expands? While it's not generally reliable to try applying ordinary intuition about mechanics to situations where GR rules, I believe it's true that things rotate faster as they collapse. But I don't see anything in the article contradicts that; presumably the small effect they observed in the present day would have been much more noticeable when the universe was smaller. Quote Share this post Link to post Share on other sites
LuisBSF 26 Posted August 10, 2011 If only by the law of conservation of angular momentum, then yes. But as you say it's dangerous to apply everyday common sense to such matters as there might be other interactions at work that might not be apparent on a first glance, particularly not when the object being observed is the entire universe. Quote Share this post Link to post Share on other sites
Rotwang 323 Posted August 10, 2011 If only by the law of conservation of angular momentum, then yes. This is a good example to illustrate my point: in GR, unless your spacetime has an exact rotational symmetry (more precisely, a Killing vector) you simply don't have any law of global conservation of angular momentum. Quote Share this post Link to post Share on other sites
LuisBSF 26 Posted August 10, 2011 It couldn't possibly have any. Should the universe be completely symmetric, all matter would've been completely annihilated by antimatter during the first moments of existence, to mention just one direct consequence of it. Plus the law conservation of angular momentum is valid for an object that rotates through a vacuum that exists within space time (any law of physics for all we know is only valid within our universe). The universe might not be such a thing either. Quote Share this post Link to post Share on other sites
Rotwang 323 Posted August 10, 2011 It couldn't possibly have any. Should the universe be completely symmetric, all matter would've been completely annihilated by antimatter during the first moments of existence, to mention just one direct consequence of it. This assumes that there was an equal quantity of matter and antimatter in the early universe. We don't know whether that was the case or not. Of course, we can tell that the universe doesn't have exact rotational symmetry by simply looking at it. Plus the law conservation of angular momentum is valid for an object that rotates through a vacuum that exists within space time No, in the absence of a Killing vector generating rotations there is no such law. The problem is that angular momentum isn't even defined globally. Quote Share this post Link to post Share on other sites
LuisBSF 26 Posted August 10, 2011 I stand corrected. Quote Share this post Link to post Share on other sites
