Trace Anomaly as Signature of Conformality in Neutron Stars.

  title={Trace Anomaly as Signature of Conformality in Neutron Stars.},
  author={Yuki Fujimoto and Kenji Fukushima and Larry Mclerran and Michał Praszałowicz},
  journal={Physical review letters},
  volume={129 25},
We discuss an interpretation that a peak in the sound velocity in neutron star matter, as suggested by the observational data, signifies strongly coupled conformal matter. The normalized trace anomaly is a dimensionless measure of conformality leading to the derivative and the nonderivative contributions to the sound velocity. We find that the peak in the sound velocity is attributed to the derivative contribution from the trace anomaly that steeply approaches the conformal limit. Smooth… 

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