Symmetries are not hard to find. Plates in the china shop look the same when rotated; serving platters are identical to their mirror reflection. But much of the world is messy and asymmetric, and discovering how certain symmetries are violated, or broken, can reveal deeper physics.

Nambu developed a mathematical mechanism for spontaneous symmetry breaking in particle physics. Spontaneous symmetry breaking occurs in systems that under certain conditions are symmetric, but whose lowest energy state is not. A classic example is a hot chunk of magnetic material, in which the atomic-scale “bar magnets” point in random directions, making its interior symmetric under rotation. But as the material cools, these elements align in a single direction, and the metal becomes magnetized. The rotational symmetry is broken in this lowest energy configuration, hiding the symmetry that still exists in the equations of electromagnetism.

Something similar happens in a superconductor. At high temperature, the electrons in the material are free to roam around randomly, but below a critical temperature their lowest energy state is one in which they pair up. Nambu modeled this behavior in the context of quantum field theory. He was able to explain the expulsion of magnetic fields by superconductors in a new and elegant way involving the breaking of symmetry in the field equations when electrons pair up.

https://physics.aps.org/story/v22/st13

Spontaneous symmetry breaking (SSB), which is the main subject of my talk, is a phenomenon where a symmetry in the basic laws of physics appears to be broken. In fact, it is a very familiar one in our daily life, although the name SSB is not. For example, consider an elastic straight rod standing vertically. It has a rotational symmetry; it looks the same from any horizontal direction. But if one applies increasing pressure to squeeze it, it will bend in some direction, and the symmetry is lost. The bending can occur in principle in any direction since all directions are equivalent. But you do not see it unless you repeat the experiment many times. This is SSB. A part of Nobel Lecture by Yoichiro Nambu (2008)

http://journals.aps.org/rmp/abstract/10.1103/RevModPhys.81.1015#fulltext

In a particle accelerator, beams of subatomic particles are boosted to nearly the speed of light and then brought into collision with either a stationary target or another beam of accelerated particles coming head-on.

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?reload=true&arnumber=4629896

So, this question arise that what is the relationship between speed and Spontaneous symmetry breaking?

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