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> > > Atomic structure holography using thermal neutrons should copy all > > Atoms and its Electrons Orbital Paths Around Atoms of the Homo sapiens > > Brain and Mind > > I hope someone can make me a system. > > > > Having a problem with mortality, are we? > > Brian The only problem is No Cash I only have My PC. physicists have made a new type of ultra-precise laser pointer by "squeezing" a beam in two directions. hans bachor and colleagues at the australian national university in canberra and the universiti pierre et marie curie in paris are able to position the beam with a precision of 1.6 angstroms. this is almost 1.5 times better than the theoretical limit for a conventional laser. the technique could be used to improve the performance of a range of optical instruments and also in imaging applications in physics and biology (n treps et al. 2003 science 301 940). laser beams suffer from quantum noise and until recently researchers believed that this noise would set a fundamental limit on the resolution of devices. however, it is possible to overcome these limitations by squeezing the fluctuations (that is, reducing the uncertainty) in one of the variables describing the beam, at the expense of increasing the fluctuations in another variable. bachor and colleagues mixed a standard laser beam with two squeezed light beams. they found that the fluctuation amplitude of the laser beam decreased from 2.3 angstroms - the standard quantum noise limit - to 1.6 angstroms. the researchers managed to order the photons in the squeezed beams in two different transverse directions at the same time. this cancels out the quantum noise in a particular measurement position. "such an effect had been predicted but has never been seen until now," team member nicolas treps told physicsweb. "what finally made this work possible was the merging of the beams in an optical cavity and the ability to operate the two sources of squeezed light simultaneously." the team now hopes to exploit the technique in atomic force microscopy, measurements of refractive index and studies of molecules in living cells. however, treps and co-workers say that the technique still requires more fundamental work and that real applications will follow only after researchers have developed easy-to-use, efficient sources of squeezed light [from physicsweb] - physicists have created "slow" and "fast" light in a crystal at room temperature for the first time. the team at the university of rochester in the us used an 'alexandrite' crystal to reduce the speed of light to just 91 metres per second, and also to make a laser pulse travel faster than the speed of light. previously these effects - which are not in conflict with special relativity - had only been observed at cryogenic temperatures or in complicated experimental set-ups. the new technique could be used for applications such as optical data storage, optical memories and quantum information devices (m bigelow et al. 2003 science 301 200). light travels at a speed of 300 million metres per second in a vacuum, but in recent years physicists have managed to slow laser pulses down to speeds of metres per second - or to bring them to a complete halt - in ultracold gases. in similar experiments physicists have observed superluminal or faster-than-light pulse propagation. these effects have also been observed in crystals at cryogenic temperatures and in "hot" gases. now matthew bigelow, nick lepeshkin and robert boyd have observed the same effects in a much simpler system - a crystal at room temperature. all the experiments exploit changes in the refractive index of an optical medium caused by quantum interference effects. whereas previous experiments relied on a process known as "electromagnetically induced transparency", the rochester team exploited "coherent population oscillations" in the crystal. this involves shining two lasers - a pump beam and a weaker probe beam - at the crystal. under certain conditions the probe beam experiences reduced absorption over a narrow range of wavelengths. the refractive index also increases rapidly in this "spectral hole", which leads to a much reduced group velocity - the velocity at which a laser pulse travels - for the probe beam. earlier this year, the rochester team used this technique to reduce the group velocity of a laser pulse to 58 metres per second in a ruby crystal at room temperature. bigelow and co-workers have now repeated this feat in a crystal of alexandrite. moreover, by using different wavelengths they can make a spectral "antihole" in which the absorption is higher, and which leads to superluminal propagation. they observed light speeds of 91 metres per second for a laser with a wavelength of 488 nanometres, and minus 800 metres per second for wavelengths of 476 nanometres. negative speeds indicate superluminal velocities because the pulses appear to leave the crystal before they enter it under these conditions. "our technique is applicable to many solid materials, not just alexandrite," lepeshkin told physicsweb. "another important feature of our approach is the ability to cover a fairly broad range of optical frequencies." the researchers will now investigate solid state materials with higher bandwidth to use in their system that are suitable for communication applications. author belle dumi is science writer at physicsweb - name: joseph m graham jr. address: 1701 ocean ave. asbury park, nj 07712 united states day phone: (732) 775-0265 evening phone: (732) 775-0265 apt apt.26d email address: [EMAIL PROTECTED] - we don't need to understand the brain in order to replace it as a whole copy into the holographhic computer. and after the brain is in the holographhic computer we can cut the connectivity to the hippocampus. and find a fact of time or event that happen in the past memory. no more lies with a hippocampus. p.s. what did bill clinton do in the house.
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