Exploring the standard model of physics without the high-energy collider
August 10, 2009
Scientists have measured the largest effect of the "weak interaction" -- one of the four fundamental forces of nature -- ever observed in an atom. Credit: Image copyright American Physical Society [Illustration: Carin Cain]
Scientists at the University of California, Berkeley, and Lawrence Berkeley National Laboratory in the US, have performed sophisticated laser measurements to detect the subtle effects of one of nature's most elusive forces - the "weak interaction". Their work, which reveals the largest effect of the weak interaction ever observed in an atom, is reported in Physical Review Letters and highlighted in the August 10th issue of APS's on-line journal Physics.
Along with gravity, electromagnetism and the strong interaction that holds protons and neutrons together in the nucleus, the weak interaction is one of the four known fundamental forces. It is the force that allows the radioactive decay of a neutron into a proton - the basis of carbon dating - to occur. However, because it acts over such a short range - about a tenth of a percent the diameter of the proton - it is almost impossible to study its effect without large, high-energy particle accelerators.
Theorists had predicted that the weak interaction between an atom's electrons and its nucleus could be quite large in Ytterbium (element 70 in the periodic table). To actually see this interaction, though, Dmitry Budker and his group at UC Berkeley had to carefully perform delicate measurements based on fundamental quantum mechanical effects and systematically eliminate other spurious signals.
The effect Budker and his colleagues see in Ytterbium is about 100 times bigger than what has been seen in Cesium, the atom in which most experiments in this field have been performed so far. The finding of such a large effect in Ytterbium poses an exciting opportunity to use tabletop atomic physics techniques as part of sensitive searches for new physics that complement ongoing efforts at the world's high-energy colliders.
More information:
Condensed matter physics: Melting the world's smallest raindrop
Calorimetric observation of the melting of free water nanoparticles at cryogenic temperatures [To appear in Physical Review Letters accompanied by a Viewpoint in Physics]
http://physics.aps.org
Source: American Physical Society
Jul 22, 2009 |
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This effect is pronounced the more, the less reversible electron transition is, i.e. for energy transitions between spherical s-orbitals. These transitions are of low probability ("prohibited energy levels"), because spherical orbitals are radiating EM wave poorly (whereas p-orbitals are behaving like antenna so they can radiate energy smoothly). Similar mechanism may be responsible for anomalous "cold fusion" effects, so it may become important even from practical point of view.
http://www.aether...ity1.gif
IMO the same effect can be observed even by "naked eye" on rotating black holes, which are emanating polar jets in assymetric way quite often. We can imagine black hole as an analogy of giant atom nuclei, here.
http://www.aether..._m87.jpg
Has symmetry violation really been proven? Maybe not:
Read on pg. 28 at the link.
http://www.scribd...-Physics
http://www.spring...RG71.pdf -measuring gravity
http://www.spring...4P4H.pdf -ideal gas neutron star gravity calculations
Some help and coaching get, please.
No, it's not surface tension, to have surface tension you first need to have a surface. Fundamental particles don't have one.
http://hypertextb...na.shtml
Model of elementar particle by AWT:
http://www.aether...hole.gif
We can define diameter of particles like radius, when repulsive weak force changes into attractive strong nuclear force.