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}
}

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References

SHOWING 1-10 OF 11 REFERENCES

Remarks on Time-Space Noncommutative Field Theories

We propose a physical interpretation of the perturbative breakdown of unitarity in time-like non-commutative field theories in terms of production of tachyonic particles. These particles may be

Divergencies in a field theory on quantum space

Space-time noncommutative field theories and unitarity

D-branes and Deformation Quantization

In this note we explain how world-volume geometries of D-branes can be reconstructed within the microscopic framework where D-branes are described through boundary conformal field theory. We extract

On theories with light-like noncommutativity

We show that field theories with light-like noncommutativity, that is with θ0i = -θ1i, are unitary quantum theories, and that they can be obtained as decoupled field theory limits of string theory

The quantum structure of spacetime at the Planck scale and quantum fields

We propose uncertainty relations for the different coordinates of spacetime events, motivated by Heisenberg's principle and by Einstein's theory of classical gravity. A model of Quantum Spacetime is

S Matrix in the Heisenberg Representation

The elements of the S matrix are calculated directly from an operator formalism, using the method of Yang and Feldman. This method has the advantage of providing a simple and direct justification of

Closed star products and cyclic cohomology

We define the notion of a closed star product. A (generalized) star product (deformation of the associative product of functions on a symplectic manifold W) is closed iff integration over W is a