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December 7.1996-Scientists first discovered the "back in time" phenomenon

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December 7, 1996 (Rat-October 27), the scientists first discovered the phenomenon of "back in time".

Scientists first discovered the "back in time" phenomenon
European Atomic Research Centre Reference December 1996, the European Atomic Energy Research Center, researchers found that the presence of asymmetry on the time the sign of K mesons in the conversion process. This finding may help to perfect the Big Bang theory, but it has shaken the basic laws of physics should be symmetrical in time "point of view.
daily life, we could not turn the clock back. The arrow of time is always only one orientation. The elderly can not be young, broken vase can not be undone, the past and the future boundaries clear. However, physicists in the eyes, the time they can be reversed. For example, a pair of photons collide to produce an electron and a positron, electron-positron meet the same to produce a pair of photons, this process is in line with the basic laws of physics are symmetric in time. If the camera captured one of the two processes, and then play, viewers will not be able to determine if the tape is in forward or reverse playback. In this sense, time is not the direction.
physics, this does not distinguish the characteristics of the past and the future is called time symmetry. The laws of classical physics assume no direction, and indeed through the test in the macroscopic world. But in recent decades, physicists have been research time symmetry is equally applicable in the microscopic world. European Atomic Energy Research Center, a team after a three-year study recently finally got the breakthrough. Their observed experimentally demonstrated for the first time that, at least in the neutral K meson decay process, time, contrary to the symmetry. In the experiment, the composition of this group
by nearly 100 researchers from nine countries studied the K meson anti-the K meson mutual conversion process. Meson is a quality larger than the electron, but smaller than the proton and the neutron, integer spin, to participate in the strong interaction between the particles, the internal quantum numbers can be divided into the π meson, ρ meson and K meson. In the experiment, the researchers found that anti-K mesons conversion the K mesons rate than time reversal process, ie K mesons into anti-K mesons come faster. This is the history of physics is the first direct observation to the time asymmetry. the modern universe theory had thought
the beginning of the Big Bang should produce the same amount of matter and antimatter today's universe is mainly dominated by the material world, a phenomenon that has been confusing. CERN experimental proof and antimatter into substances faster than its reverse process, so it is far more than for the quality of the universe for why anti-substance provides part of the answer.
In addition, new results on the basic symmetry of physics law of research has important significance. Physicists have long believed that, in addition to the basic laws of physics without time directional, object reflection in space physics, as well as the transformation process of the particles and anti-particles should follow symmetry. Time, parity and charge conservation law is considered to be one of the support the foundation of modern physics. (History TodayOnHistory.com)
the 1950s, physicists have discovered that some of the conservation law is sometimes not fully satisfy the symmetry. Chinese-American physicist Chen Ning Yang and Tsung-Dao Lee proposed the theory and confirmed by the experiments, after Americans James - Cronin and Val - Fitch violation of parity and charge K mesons decay process was found weak interaction in the parity violation Joint symmetry rules, so they are awarded the Nobel Prize in Physics. Time, parity and charge as a whole is considered to be conserved, physicists have had to guess that time in a particular case would be contrary to the symmetry. The CERN results demonstrated for the first time that this conjecture.
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