# On the unitarity problem in space/time noncommutative theories

@article{Bahns2002OnTU, title={On the unitarity problem in space/time noncommutative theories}, author={Dorothea Bahns and Sergio Doplicher and Klaus Fredenhagen and Gherardo Piacitelli}, journal={Physics Letters B}, year={2002}, volume={533}, pages={178-181} }

## 215 Citations

### Particle Physics on Noncommutative Space-Time

- Mathematics
- 2003

This is a concise overview of the construction of Yang-Mills theories with realistic gauge groups on noncommutative generalizations of space-time and of the construction of the noncommutative…

### UV/IR duality in noncommutative quantum field theory

- Mathematics
- 2011

We review the construction of renormalizable noncommutative Euclidean ϕ4-theories based on the UV/IR duality covariant modification of the standard field theory, and how the formalism can be extended…

### EMERGENCE OF TIME FROM DIMENSIONAL REDUCTION IN NONCOMMUTATIVE GEOMETRY

- Philosophy
- 2006

By considering a new form of dimensional reduction for noncommutative field theory, we show that the signature of spacetime may be changed. In particular, it is demonstrated that a temporal dimension…

### Time-ordered perturbation theory on non-commutative spacetime II: Unitarity

- Physics
- 2002

Abstract. We examine the unitarity issue in the recently proposed time-ordered perturbation theory on noncommutative (NC) spacetime. We show that unitarity is preserved as long as the interaction…

### Noncommutative Instantons on d = 2n Planes from Matrix Models

- Mathematics
- 2003

In the case of an invertible coordinate commutator matrix θij, we derive a general instanton solution of the noncommutative gauge theories on d = 2n planes given in terms of n oscillators.

### On the unitarity of higher derivative and nonlocal theories

- Mathematics, Physics
- 2007

We consider two simple models of higher derivative and nonlocal quantum systems. It is shown that, contrary to some claims found in literature, they can be made unitary.

### The Interface of Noncommutative Geometry and Physics

- Physics
- 2002

As a mathematical theory, noncommutative geometry (NCG) is by now well established. From the beginning, its progress has been crucially influenced by quantum physics: we briefly review this…

### Ultraviolet Finiteness of the averaged Hamiltonian on the noncommutative Minkowski space

- Mathematics
- 2004

It is shown that the Hamiltonian approach for a $\phi^3$-interaction on the 4-dimensional noncommutative Minkowski space leads to an ultraviolet finite $S$-matrix if the noncommutativity is averaged…

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