Why Higher Energy?

Why the quest for ever-higher energy for the particle accelerators? One answer is to break things apart so that you can look at the pieces. But a deeper reason lies in the essential wave-particle duality and the fact that the attainable resolution of any type of imaging system is on the order of the wavelength of the waves used for the imaging.

Light microscopes cannot resolve detail smaller than the wavelength of light. This limitation is related to the Rayleigh criterion for the ultimate resolution of an imaging system. Electron microscopes have higher resolution because the associated wave properties of the electrons have much shorter wavelengths. The de Broglie relationship which allows us to calculate these wavelengths implies that a higher momentum (and thus higher energy) electron has a shorter wavelength.

The extremely small nuclear size implies that much higher energy particles will have to be used to resolve details of its structure, and to probe to smaller detail will require higher and higher energy particles with which to do the imaging.

Ultimately, the energy required for the resolution of smaller structural details will be beyond our capacity on the Earth. This has led to a closer cooperation between the search for the very small and the search for the very large, because only in the consideration of cosmology and the high energies involved in formation processes in the universe can we find information about the very small.

Connection between particles and cosmology

The search for the very small requires very high energies. The discoveries necessary for the electroweak unification were near the upper end of available energies in the current generation of particle accelerators. Establishing Grand Unification is beyond the practical limits of earthbound laboratories. This forces particle physicists to look outward to astrophysical phenomena which may have enough energy to shed some light on further attempts at unifying the four fundamental forces.

Modern efforts at formulating cosmological models like the Big Bang model were stimulated by evidence like the 3 K cosmic background radiation. But when modeling a very hot, high-energy universe where matter would be in a very different state than matter on the Earth, cosmologists found it necessary to make use of the results of the particle physicists at the high energy accelerators. The investigators of the very large and the very small have been brought together in cooperation; the study of the origin of matter and its basic nature have much in common.