The Primordial Gravitational Wave In Dinkic Inflationary Model And The QCD Phase Transition Gravitational Wave

The gravitational waves directly detected by LIGO indicates the arrival of the era of gravitational wave astronomy and gravitational wave cosmology.More and more gravitational wave events are expected to be detected by existing and planned detectors in the future.Gravitational waves combined with other cosmological probes will open a new window on the universe.Gravitational wave physics is not only related to the theory of gravity,but also to fundamental physics,cosmology,and astronomy.In this paper,we first study the primordial gravitational waves generated by a new inflation model--the Dinkic inflation model,and then we study the phase transition gravitational waves generated by the confinement and deconfinement phase transition in the presence of an external magnetic field.A new class of inflation models which generalize the Dirac-Born-Infeld(DBI)action with the addition of a nonminimal kinetic coupling term,We dub this model as the "DBIinspired non-minimal kinetic coupling"(Dinkic)inflation model.The nonminimal kinetic coupling term does not bring new dynamical degree of freedom,so the equations of motion remain of second order.However,with such a coupling,the action is no longer linear with respect to the Einstein curvature term(R or Gμv),the perturbation equation of motion gets a correction of k4,the scale-invariance of the power spectrum remains valid,both in largek and small-k limits.In this paper,we have studied the spectral index and its running in the new DBI inflation model,mainly focusing on the potential-driven case.We have calculated the power spectrum,spectral index,the running of the spectral index,the tensor spectral index and tensor/scalar ratio.We have also compared our results with the current PLANCK/BICEP observational data.From the numerical plots,we can see that in the large region parameter choice,the quantities of our model can be acceptable within current observation.The tensor-to-scalar ratio can be suppressed to meet with the observation due to the non-minimal coupling term.We found that the Dinkic model,after taking some special potential,would get a smaller tensor/scalar ratio,in line with the observed trend of PLANCK/BICEP.The study of QCD phase structure in the presence of an external magnetic field has attracted considerable attention.The study of holographic model shows that there exists a critical magnetic field Bc,in which the critical temperature Tc vanishes;for B<Bc we have an inverse magnetic catalysis and for B>Bc we have a magnetic catalysis.In this paper,we studied the influence of magnetic field on phase-change gravitational wave,and found that for the magnetic field B<Bc,the energy density of phase transition gravitational wave will increase with the enhancement of the magnetic field.For the magnetic field B>Bc,the energy density of the phase transition gravitational wave will decrease with the enhancement of the magnetic field.The phase transition gravitational waves under the magnetic field with different magnitude can be detected by pulsar timing arrays IPTA and huge radio telescope SKA.