Using a dynamical system method,we study a Friedmann-Robertson-Walker(FRW)cosmological model within the context of f(Q,C)gravity,where Q is the non-metricity scalar and C represents the boundary term,considering both interacting and non-interacting models.A set of autonomous equations is derived,and solutions are calculated accordingly.We assess the critical points obtained from these equations,identify their characteristic values,and explore the physical interpretation of the phase space for this system.Two types of f(Q,C)are assumed:(i)f(Q,C)=Q+αQ+βClogC and(i)f(Q,C)=Q+αQ+β/C,where α and β are the parameters.In Model I,we obtain two stable critical points,whereas in Model Il,we identify three stable critical points for both interacting and non-interacting models.We examine the behavior of phase space trajectories at every critical point.We calculate the values of the physical parameters for both systems at each critical point,indicating the accelerated expansion of the Universe.
Tsallis nonextensive statistics is applied to study the transport coefficients of strongly interacting matter within the Polyakov chiral quark mean field model(PCQMF).Nonextensivity is introduced within the PCQMF model through a dimensionless parameter q to examine the viscous properties,such as shear viscosity(η)and bulk viscosity(σ_(el)),and conductive properties,such as electrical conductivity(c_(vq))and thermal conductivity(κ).Additionally,some key thermodynamic quantities relevant to the transport coefficients,such as the speed of sound(c_(sq)^(2))and specific heat at constant volume(c_(vq)),are calculated.The temperature dependence of the transport coefficients is explored through a kinetic theory approach with the relaxation time approximation.The results are compared to those of the extensive case where q approaches 1.The nonextensive q parameter is found to have a significant effect on all transport coefficients.We find that the nonextensive behaviour of the medium enhances specific shear viscosity,as well as conductive coefficientsσ_(el)/T and k/T(2).In contrast,the normalized bulk viscosity is found to decrease as the nonextensivity of the medium increases.We also studied the transport coefficients for finite values of chemical potentials.The magnitudes ofη,σ_(EL),andκincrease at lower temperatures,whileζ_(b)is found to decrease for systems with non-zero chemical potential.
