Symmetry arguments in physics

https://doi.org/10.1016/S0039-3681(99)00012-6Get rights and content

Abstract

Physicists often appeal to the beauty of a theory as a way to judge its credibility, and the most prevalent component of this beauty is symmetry. This paper describes the role and structure of symmetry arguments in physics. It demonstrates that the epistemic authority of an appeal to symmetry is based on empirical evidence and is independent of any aesthetic judgment. Furthermore, symmetry in nature is not evidence of design. Just the opposite, symmetry indicates a lack of planning. It is about nature's disregard for details.

Section snippets

Beauty is symmetry

A snowflake is a thing of beauty. It is also a thing of symmetry. Each spoke displays a mirror reflection along its radial axis, and the whole crystal shows rotational symmetry by repeating the design exactly six times in one complete turn. Perhaps the beauty we feel is rooted in the geometric symmetry of structure.

The link between beauty and symmetry does indeed exist in physics, and it is safe to say that beauty essentially means symmetry in that context. The theoretical description of

Substantive symmetry arguments

A symmetry is an invariance under some operation of change. How is a symmetry, a specific symmetry, used as an epistemic tool? That is, how can a criterion of symmetry be used to direct theorizing in the general direction of the truth? Of course, it will not be fool-proof, but perhaps it can better the odds.

Bas van Fraassen (1989, p.242) distinguishes between substantive symmetry arguments and `symmetry arguments proper'. It is the former, the substantive arguments, that are of more

Conclusion

The case of gauge symmetry is similar to that of the principle of relativity. Together they point to general conclusions about substantive symmetry arguments in physics. These arguments make no assumptions or inferences about symmetry in general. They are always about some specific symmetry or other. Furthermore, these arguments do not simply assume that the specific symmetry is a fact of nature, and then use it as a standard for judging theories. They begin with observation.

Sunny Auyang (1995,

References (16)

  • Aitchison, I. and Hey, A. (1982) Gauge Theories in Particle Physics (Bristol: Adam...
  • Auyang, S. (1995) How is Quantum Field Theory Possible? (New York: Oxford University...
  • Barrow, J. (1988) The World within the World (New York: Oxford University...
  • Einstein, A. (1995) (originally published 1920) Relativity (Amherst: Prometheus...
  • Frauenfelder, H. and Henley, E. (1974) Subatomic Physics (Englewood Cliffs: Prentice...
  • P Ginsparg et al.

    Desperately Seeking Superstrings?

    Physics Today

    (1986)
  • J Martin

    Aesthetic Constraints in Theory Selection

    British Journal for the Philosophy of Science

    (1989)
  • Mauldin, J. (1986) Particles in Nature (Blue Ridge Summit: Tab...
There are more references available in the full text version of this article.

Cited by (0)

View full text