The Physics arXiv Blog
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Quantum direct communication: secrecy without key distribution
An interesting development in the world of quantum encryption. In the last couple of years, we’ve seen a number of quantum key distribution systems being set up that boast close-to-perfect security (although they’re not as secure as the marketing might imply). These systems rely on two-part security. The first is the quantum part which reveals…
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Levitating gas pipelines
Great to see one of the arXiv’s most creative minds posting again today. Alexander Bolonkin–he of “In Outer Space without a Space Suit?” and “Floating Cities, Islands and States” fame–is back with another startling idea. Methane is significantly lighter than air and so could be used to levitate the pipes it flows through. These aerial…
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Loop quantum cosmology: a brief overview
Abhay Ashtekar, a physicist at the Pennsylvania State University is one of the founders of loop quantum cosmology and also a part-time populariser of science. Today, he uses both of these attributes to produce a fascinating overview of loop quantum cosmology that non-specialists will find enlightening. A recommended read. Ref: arxiv.org/abs/0812.0177: Loop Quantum Cosmology: An…
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Quantum test found for mathematical undecidability
It was the physicist Eugene Wigner who discussed the “unreasonable effectiveness of mathematics” in a now famous paper that examined the profound link between mathematics and physics. Today, Anton Zeilinger and pals at the University of Vienna in Austria reveal this link at its deepest. Their experiment involves the issue of mathematical decidability. First, some…
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How ribosomal traffic cops keep bacteria alive
Ribosomes are the genetic Turing machines that translate nucleic acid into protein. And fast growing bacteria need plenty of them. E coli bacteria, for example, contain some 73000 ribosomes per cell. Given that E coli populations double every 20 minutes, new ribosomes have to be created at a fantastic rate. The process requires ribosomal RNA…
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Chit ‘n’ chatter
The best of the rest from the physics arXiv this week: Recent Developments in Superstatistics Interpretations of Quantum Mechanics: a Critical Survey Introduction to Protein Folding for Physicists Heat Flow of the Earth and Resonant Capture of Solar 57-Fe Axions Large-Scale Cosmic Flows and Moving Dark Energy
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Steganophony–when internet telephony meets steganography
Steganophony is the term coined by Wojciech Mazurczyk and Józef Lubacz at the Warsaw University of Technology in Poland to describe the practice of hiding messages in internet telephony traffic (presumably the word is an amalgamation of the terms steganography and telephony). The growing interest in this area is fueled by the fear that terrorist…
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A clue in the puzzle of perfect synchronization in the brain
“Two identical chaotic systems starting from almost identical initial states, end in completely uncorrelated trajectories. On the other hand, chaotic systems which are mutually coupled by some of their internal variables often synchronize to a collective dynamical behavior,” write Meital Zigzag at Bar-Ilan University in Israel and colleagues o the arXiv today. And perhaps the…
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How much force does it take to stab somebody to death?
How much force does it take to stab somebody to death? Strangely enough, forensic scientists do not know. A number of groups have attempted to measure the forces necessary to penetrate skin but the results are difficult to apply to murder cases because of the sheer range of factors at work. The type and sharpness…
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The engrossing enigma of supersolids
Almost 40 years ago, two Russian physicists predicted the existence of a new state of matter called a supersolid. They reasoned that at very low temperatures, the rules of quantum mechanics would allow a solid to move with zero resistance and that this would allow one solid to move through another like magician walking through…