LHC Machine Outreach The Large Hadron Collider (LHC) is built in a circular tunnel 27 km in circumference. The tunnel is buried around 50 to 175 m. underground. It straddles the Swiss and French borders on the outskirts of Geneva. The first beams were circulated successfully on 10th September 2008. Unfortunately on 19th September a serious fault developed damaging a number of superconducting magnets. The repair required a long technical intervention. First collisions took place on 30th March 2010 with the rest of the year mainly devoted to commissioning. 2011 was the first production year with over 5 inverse femtobarns delivered to both ATLAS and CMS. 2012 started well with over 6 inverse femtobarns delivered by the time of the summer conferences - these data paved the way for the announcement of a/the Higgs on 4th July 2012. The LHC is designed to collide two counter rotating beams of protons or heavy ions. The beams move around the LHC ring inside a continuous vacuum guided by magnets.
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. 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.
Homepage - Large Hadron Collider Not Even Wrong I’ve just replaced the old version of my draft “spacetime is right-handed” paper (discussed here) with a new, hopefully improved version. If it is improved, thanks are due to a couple people who sent helpful comments on the older version, sometimes making clear that I wasn’t getting across at all the main idea. To further clarify what I’m claiming, here I’ll try and write out an informal explanation of what I see as the relevant fundamental issues about four-dimensional geometry, which appear even for $\mathbf R^4$, before one starts thinking about manifolds. Spinors, twistors and complex spacetime In complex spacetime $\mathbf C^4$ the story of spinors and twistors is quite simple and straightforward. While spinors are the irreducible objects for understanding complex four-dimensional rotations, twistors are the irreducible objects for understanding complex four-dimensional conformal transformations. Real forms In this case the conjugation acts in a subtle manner. Some philosophy
Science News, Articles and Information | Scientific American For One Tiny Instant, Physicists May Have Broken a Law of Nature This image of a full-energy collision between gold ions shows the paths taken by thousands of subatomic particles produced during the impact. For a brief instant, it appears, scientists at Brookhaven National Laboratory on Long Island recently discovered a law of nature had been broken. Action still resulted in an equal and opposite reaction, gravity kept the Earth circling the Sun, and conservation of energy remained intact. But for the tiniest fraction of a second at the Relativistic Heavy Ion Collider (RHIC), physicists created a symmetry-breaking bubble of space where parity no longer existed. Parity was long thought to be a fundamental law of nature. Now this law appears to have been broken by a team of about a dozen particle physicists, including Jack Sandweiss, Yale's Donner Professor of Physics. It was the equally gargantuan magnetic field produced by the plasma — the strongest ever created — that alerted the physicists that one of nature's laws might have been broken.
Space Today Online -- Solar System Planet Earth -- Ancient Astro A European researcher has interpreted carvings in a 32,500-year-old ivory tablet as a pattern of the same stars that we see in the sky today in the constellation Orion. The tablet is a sliver of ivory from the tusk of a mammoth — a large woolly animal like an elephant. Mammoths are extinct today. Carved into the ivory is what appears to be a carving of a human figure with outstretched arms and legs. The pose suggests the stars of Orion, according to Michael Rappenglueck, formerly of the University of Munich, known for his interpretation of ancient star charts painted on walls of prehistoric caves. The ivory tablet has notches carved on its sides and back, which are not understood but might be an ancient pregnancy calendar to estimate when a woman would give birth. The tiny piece of ivory was in a cave in the Ach Valley in the Alb-Danube region of Germany when it was discovered in 1979. Stone Age people. The Orion constellation is known to stargazers today as "the hunter." Summer Triangle.
Bulletproof Skin Made From Spider Silk Just last week we learned about spiders coming to the aid of burn victims. Now it looks like our friendly neighborhood arachnids are being used to create the ultimate superhero power: bulletproof human skin. Well, almost. BLOG: Artificial Skin Made From Spider Silk In her new project, 2.6g 329m/s, Dutch artist Jalila Essaidi, along with Forensic Genomics Consortium Netherlands, created a swatch of nearly bulletproof skin made from spider silk and human skin cells. By grafting spider silk between the epidermis and dermis, the skin was able to stop a bullet that was fired at a reduced speed. But that's fine with Essaidi. "With this work I want to show that safety in its broadest sense is a relative concept, and hence the term bulletproof," Essaidi said in a press release. "But even with the skin pierced by the bullet the experiment is still a success. NEWS: How To Make A Bulletproof T-Shirt [Via TechNewsDaily] photo: A bullet is repelled by a matrix of spider silk and human skin cells.