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Complete video at: http://fora.tv/2009/05/23/Marcus_Chown_in_Conversation_with_Fred_Watson Marcus Chown, author of Quantum Theory Cannot Hurt You: A Guide to the Universe, discusses the mechanics behind quantum computers, explaining that they function by having atoms exist in multiple places at once. He predicts that quantum computers will be produced within 20 years. ----- The two towering achievements of modern physics are quantum theory and Einsteins general theory of relativity. Together, they explain virtually everything about the world in which we live. But almost a century after their advent, most people havent the slightest clue what either is about. Radio astronomer, award-winning writer and broadcaster Marcus Chown talks to fellow stargazer Fred Watson about his book Quantum Theory Cannot Hurt You. - Australian Broadcasting Corporation Marcus Chown is an award-winning writer and broadcaster. Formerly a radio astronomer at the California Institute of Technology, he is now cosmology consultant of the weekly science magazine New Scientist. The Magic Furnace, Marcus' second book, was chosen in Japan as one of the Books of the Year by Asahi Shimbun. In the UK, the Daily Mail called it "a dizzy page-turner with all the narrative devices you'd expect to find in Harry Potter". His latest book is called Quantum Theory Cannot Hurt You.

There are differences between the group's demonstrations. For crystals, Tittel's group used thulium-doped lithium niobate, whereas Gisin's group opted for neodymium-doped yttrium silicate. In addition, a different type of laser set-up has favoured Gisin's group, which reports a maximum storage time of some 200 ns at an efficiency of more than 20%; Tittel's group reports a storage time of 7 ns at an efficiency of 2%. On the other hand, the quantum memory of Tittel's group functions at a bandwidth of 5 GHz - some 40 times greater than Gisin's group - which means, potentially, far more information could be sent in the same time.

ScienceDaily (June 4, 2011) - Do the principles of quantum mechanics apply to biological systems? Until now, says Prof. Ron Naaman of the Institute's Chemical Physics Department (Faculty of Chemistry), both biologists and physicists have considered quantum systems and biological molecules to be like apples and oranges. But research he conducted together with scientists in Germany, which appeared recently in Science, shows that a biological molecule -- DNA -- can discern between quantum states known as spin.

Unification theory with no extra dimensions. The first part unifies the strong nuclear force with the gravitational force in a mathematical way; the quantum vacuum is treated as a deformable system by the strong nuclear force. The second part unifies the nuclear force with the quantum vacuum in a hypothetical structure; the quantum vacuum is treated as a supersymmetric and metastable system with properties related to the different types of particles' motion.

Engineers at Stevens Institute of Technology have developed a technique to optically modulate the frequency of a laser beam and create a signal that is disrupted significantly less by environmental factors, says Dr. Rainer Martini. The research provides for enhanced optical communications, allowing mobile units not tied to fiber optic cable to communicate in the range of 100 GHz and beyond, the equivalent of 100 gigabytes of data per second. Eventually, the team hopes to extend the reach into the terahertz spectrum. The frequency or amplitude modulation of middle infrared quantum cascade lasers has been limited by electronics, which are barely capable of accepting frequencies of up to 10 GHz by switching a signal on and off.  Marini and his team have developed a method to optically induce fast amplitude modulation in a quantum cascade laser to control the laser's intensity. Their amplitude modulation system employed a second laser to modulate the amplitude of the middle infrared laser, using light to control light. The current detector is only capable of detecting frequencies up to 10 GHz, but Dr. Martini is confident that a new detector will make the system capable of much higher frequencies. With an optical system that is stable enough, satellites may one day convert to laser technology, resulting in a more mobile military and super-sensitive scanners, as well as faster Internet for the masses, says Martini. Ref.: "Optically induced fast wavelength modulation in a quantum cascade laser," Applied Physics Letters, July 7, 2010.

This unprecedented atomic accuracy may yield the elementary building block for a future quantum computer with unparalleled computational efficiency.

LEDsThe strange quantum state of entanglement isn't just challenging to think about, it's hard to create. This "spooky" phenomenon-in which two particles are linked, even if they're separated by distance-can be created by scientists in the lab using bulky lasers. But scientists published a study in Nature today in which they created a light-emitting diode (LED) that produces entangled photons.

(PhysOrg.com) -- An international team has removed a major obstacle to engineer quantum systems that will play a key role in the computers, communication networks, and even biomedical devices of the future.

In a step toward a generation of ultrafast computers, physicists have used bursts of radio waves to briefly create 10 billion quantum-entangled pairs of subatomic particles in silicon. The research offers a glimpse of a future computing world in which individual atomic nuclei store and retrieve data and single electrons shuttle it back and forth.

(PhysOrg.com) -- A group of physicists working out of Chalmers University of Technology in Gothenburg, Sweden, have succeeded in proving what was until now, just theory; and that is, that visible photons could be produced from the virtual particles that have been thought to exist in a quantum vacuum. In a paper published on arXiv, the team describes how they used a specially created circuit called a superconducting quantum interference device (SQUID) to modulate a bit of wire length at a roughly five percent of the speed of light, to produce visible "sparks" from the nothingness of a vacuum.

Video courtesy of Association of Science - Technology Centers (ASTC), representing the science centre and museum field worldwide. To learn more, visit http://www.astc.org/. Follow us on Twitter: @ScienceCenters. Tel-Aviv University demos quantum superconductors locked in a magnetic field (www.quantumlevitation.com).

Aaron O'Connell and colleagues at the University of California, Santa Barbara, did not actually produce a cat that was dead and alive at the same time, as Erwin Schrödinger proposed in a notorious thought experiment 75 years ago. But they did show that a tiny resonating strip of metal - only 60 micrometres long, but big enough to be seen without a microscope - can both oscillate and not oscillate at the same time. Alas, you couldn't actually see the effect happening, because that very act of observation would take it out of superposition.

(PhysOrg.com) -- Researchers from the National Renewable Energy Laboratory (NREL) have reported the first solar cell that produces a photocurrent that has an external quantum efficiency greater than 100 percent when photoexcited with photons from the high energy region of the solar spectrum

...Historians of science have always had a soft spot for the history of theoretical physics. The great theoretical advances of this century -- relativity and quantum mechanics -- have been documented in fascinating historical accounts that have captivated the mind of the cultivated public. There are no comparable studies of the relations between science and engineering. Breaking with the tradition of the Fachidiot, theoretical physicists have bestowed their romantic autobiographies on the world, portraying themselves as the high priests of the reigning cult.