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[escepticos] Mas noticias con enjundia... La observacion afecta a la realidad...

Jeje... XDD Siento que este en ingles... ¿Algun comentario? XDD

	FUENTE: http://www.sciencedaily.com/story.asp?filename=980227055013

	Quantum Theory Demonstrated: Observation Affects Reality 

                 REHOVOT, Israel, February 26, 1998--One of the most bizarre premises of
                 quantum theory, which has long fascinated philosophers and physicists alike,
                 states that by the very act of watching, the observer affects the observed

                 In a study reported in the February 26 issue of Nature (Vol. 391, pp.
                 871-874), researchers at the Weizmann Institute of Science have now
                 conducted a highly controlled experiment demonstrating how a beam of
                 electrons is affected by the act of being observed. The experiment revealed
                 that the greater the amount of "watching," the greater the observer's influence
                 on what actually takes place. 

                 The research team headed by Prof. Mordehai Heiblum, included Ph.D.
                 student Eyal Buks, Dr. Ralph Schuster, Dr. Diana Mahalu and Dr. Vladimir
                 Umansky. The scientists, members of the Condensed Matter Physics
                 Department, work at the Institute's Joseph H. and Belle R. Braun Center for
                 Submicron Research. 

                 When a quantum "observer" is watching Quantum mechanics states that
                 particles can also behave as waves. This can be true for electrons at the
                 submicron level, i.e., at distances measuring less than one micron, or one
                 thousandth of a millimeter. When behaving as waves, they can simultaneously
                 pass through several openings in a barrier and then meet again at the other
                 side of the barrier. This "meeting" is known as interference. 

                 Strange as it may sound, interference can only occur when no one is watching.
                 Once an observer begins to watch the particles going through the openings,
                 the picture changes dramatically: if a particle can be seen going through one
                 opening, then it's clear it didn't go through another. In other words, when
                 under observation, electrons are being "forced" to behave like particles and
                 not like waves. Thus the mere act of observation affects the experimental

                 To demonstrate this, Weizmann Institute researchers built a tiny device
                 measuring less than one micron in size, which had a barrier with two openings.
                 They then sent a current of electrons towards the barrier. The "observer" in
                 this experiment wasn't human. Institute scientists used for this purpose a tiny
                 but sophisticated electronic detector that can spot passing electrons. The
                 quantum "observer's" capacity to detect electrons could be altered by
                 changing its electrical conductivity, or the strength of the current passing
                 through it. 

                 Apart from "observing," or detecting, the electrons, the detector had no effect
                 on the current. Yet the scientists found that the very presence of the
                 detector-"observer" near one of the openings caused changes in the
                 interference pattern of the electron waves passing through the openings of the
                 barrier. In fact, this effect was dependent on the "amount" of the observation:
                 when the "observer's" capacity to detect electrons increased, in other words,
                 when the level of the observation went up, the interference weakened; in
                 contrast, when its capacity to detect electrons was reduced, in other words,
                 when the observation slackened, the interference increased. 

                 Thus, by controlling the properties of the quantum observer the scientists
                 managed to control the extent of its influence on the electrons' behavior. The
                 theoretical basis for this phenomenon was developed several years ago by a
                 number of physicists, including Dr. Adi Stern and Prof. Yoseph Imry of the
                 Weizmann Institute of Science, together with Prof. Yakir Aharonov of Tel
                 Aviv University. The new experimental work was initiated following
                 discussions with Weizmann Institute's Prof. Shmuel Gurvitz, and its results
                 have already attracted the interest of theoretical physicists around the world
                 and are being studied, among others, by Prof. Yehoshua Levinson of the
                 Weizmann Institute. 

                 Tomorrow's Technology 

                 The experiment's finding that observation tends to kill interference may be
                 used in tomorrow's technology to ensure the secrecy of information transfer.
                 This can be accomplished if information is encoded in such a way that the
                 interference of multiple electron paths is needed to decipher it. "The presence
                 of an eavesdropper, who is an observer, although an unwanted one, would kill
                 the interference," says Prof. Heiblum. "This would let the recipient know that
                 the message has been intercepted." 

                 On a broader scale, the Weizmann Institute experiment is an important
                 contribution to the scientific community's efforts aimed at developing quantum
                 electronic machines, which may become a reality in the next century. This
                 radically new type of electronic equipment may exploit both the particle and
                 wave nature of electrons at the same time and a greater understanding of the
                 interplay between these two characteristics are needed for the development of
                 this equipment. Such future technology may, for example, open the way to the
                 development of new computers whose capacity will vastly exceed that of
                 today's most advanced machines. 

                 This research was funded in part by the Minerva Foundation, Munich,
                 Germany. Prof. Imry holds the Max Planck Chair of Quantum Physics and
                 heads the Albert Einstein Minerva Center for Theoretical Physics. 

                 The Weizmann Institute of Science, in Rehovot, Israel, is one of the world's
                 foremost centers of scientific research and graduate study. Its 2,400 scientists,
                 students, technicians, and engineers pursue basic research in the quest for
                 knowledge and the enhancement of the human condition. New ways of
                 fighting disease and hunger, protecting the environment, and harnessing
                 alternative sources of energy are high priorities.



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