Surprising nucleon behavior

Jul 30, 2010

Data from DOE's Oak Ridge National Laboratory on neutron interactions with isotopes of platinum contradict a basic assumption underpinning random matrix theory, nuclear physics models and quantum chaos.

For more than a half century, scientists have assumed that highly excited states in intermediate- to heavy-mass nuclides are chaotic, and that data support this assumption.

However, new data from the Oak Ridge Electron Linear Accelerator strongly disagree.

The new results suggest that the roughly 200 nucleons inside the platinum nuclei studied act in unison to exhibit regular rather than chaotic properties. Given the relatively high energy and large number of nucleons involved, such collective behavior is totally unexpected and unexplained.

A possible explanation is that an even more fundamental tenet of theory--something known as form invariance--is violated.

"Either way, as these assumptions underpin the nuclear , the impact of these new findings could be very broad throughout , nuclear astrophysics and in applications such as nuclear energy," said ORNL physicist Paul Koehler.

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deatopmg
3.5 / 5 (4) Jul 30, 2010
Paraphrasing Einstein - "God doesn't roll dice". And this is just one more example of that. Aside from the 19 or so "don't asks", something appears to be seriously wrong with the standard model and everything that derives from it.
Jarek
5 / 5 (1) Jul 31, 2010
There probably can be some thermal fluctuations of nucleus structure, but generally their (meta)stable states should be some (local) energy minimums - should have some concrete structure.
Stating from QM we usually look at it from momentum point of view, but after unitary (Fourier) transform we get to the spatial structure - more intuitive point of view - in which there are successfully used e.g. Skyrmion-like solitons for particle models.
To understand how nucleons combine into nucleus, what hold them together, we have understand that spin isn't pointwise like charge, but rather curve-like: that on each perpendicular plane, quantum phase makes something like this: http://demonstrat...arities/

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