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We study the effect of hedgehog suppression in the O(3)
sigma model in D=2+1. We show via Monte Carlo simulations
that the sigma model can be disordered while effectively
forbidding these point topological defects. The resulting
paramagnetic state has gauge charged matter with
half-integer spin (spinons) and also an emergent gauge field
(photons), whose existence is explicitly demonstrated.
The zero temperature ordering transition from this phase is
found to be continuous but distinct from the regular Heisenberg
ordering transition. We propose that these phases and this
phase transition are captured by the noncompact CP1 model,
which contains a pair of bosonic fields coupled to a noncompact
U(1) gauge field. Direct simulation of the transition in
this model yields critical exponents that support this claim.
We also consider the easy-plane deformation of the model and
the effects of a Zeeman field and finite temperature.
Generalization to higher dimensions and the effects of
nonzero hedgehog fugacity are discussed.
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