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## Main Question or Discussion Point

In a new paper, Smolin sketches a mechanism by which the laws of physics can be selected naturally and thus

He outlines a universal or "meta" law, from which many possible versions of physical law can emerge depending on the start-up----depending on what happens as a new region of space time and matter is initiated (possibly by budding from a prior region.)

The conjectured universal law is general enough that regions with different dimensionality, different spacetime geometry, and differently behaving matter can emerge, depending on initial conditions.

http://arxiv.org/abs/0803.2926

Lee Smolin

21 pages,

(Submitted on 20 Mar 2008)

"A simple cubic matrix model is presented, which has truncations that, it is argued, lead at the classical level to a variety of theories of gauge fields and gravity. These include Yang-Mills theories and background independent theories of connections. The latter includes Chern-Simons theory in d=3, and BF theory and general relativity in d=4. General relativity coupled to Yang-mills theory for any SU(N) may also arise from quantum corrections.

On the basis of these results we conjecture that there are large universality classes of cut-off gauge and gravity theories, connected by transformations that mix up local and spacetime symmetries.

**evolve**.He outlines a universal or "meta" law, from which many possible versions of physical law can emerge depending on the start-up----depending on what happens as a new region of space time and matter is initiated (possibly by budding from a prior region.)

The conjectured universal law is general enough that regions with different dimensionality, different spacetime geometry, and differently behaving matter can emerge, depending on initial conditions.

http://arxiv.org/abs/0803.2926

**Matrix universality of gauge field and gravitational dynamics**Lee Smolin

21 pages,

(Submitted on 20 Mar 2008)

"A simple cubic matrix model is presented, which has truncations that, it is argued, lead at the classical level to a variety of theories of gauge fields and gravity. These include Yang-Mills theories and background independent theories of connections. The latter includes Chern-Simons theory in d=3, and BF theory and general relativity in d=4. General relativity coupled to Yang-mills theory for any SU(N) may also arise from quantum corrections.

On the basis of these results we conjecture that there are large universality classes of cut-off gauge and gravity theories, connected by transformations that mix up local and spacetime symmetries.

**If our universe is described by one of these theories then the question of the choice of the laws of physics is to a large extent subsumed in the problem of the choice of initial conditions in cosmology**."
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