2004/03/12 by Walter Smilga, W. Smilga, Smilga, W.
Medicine · Physics and Astronomy · #Advanced Neuroimaging Techniques and Applications #Black Holes and Theoretical Physics #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Noncommutative and Quantum Gravity Theories #gr-qc #hep-th
paper · pdf · doi:10.48550/arxiv.hep-th/0403137
34 pages, corrected typos, added reference
openalex publication_date 2004/03/12 · arxiv created 2005/05/08 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Current theories of particle physics, including the standard model, are dominated by the paradigm that nature is basically translation invariant. Deviations from translation invariance are described by the action of forces. General relativity is based on a different paradigm: There is no translation invariance in general. Interaction is a consequence of the geometry of spacetime, formed by the presence of matter, rather than of forces. In recent years the formation of spacetime on a quantum mechanical level, has been intensively studied within the framework of spin foams, following an old idea from R. Penrose. In this connection it would be appropriate to reconsider the meaning of those paradigms and attempt to apply the paradigm of general relativity to particle physics. A spin foam model with underlying SO(3,2) symmetry is well-suited for this purpose. It represents a purely geometric model in the sense of the second paradigm. By applying perturbative methods, starting from a translation invariant first approximation, this model is reformulated in the sense of the first paradigm. It will be shown that the model then defines a spacetime manifold equipped with a particle theory in the form of locally interacting quantized fields. This includes all four types of interaction: electromagnetic, weak, chromodynamics and gravitation together with realistic numerical values of the corresponding coupling constants.