Our goal is to extend the open thermodynamic model of cortical neurodynamic Freeman hypothesis using the theoretical Carnot and then Rankine Cycles to define biomarkers for mean field energy versus entropy change and relevancy to temperature. We are using the Rankine cycle to incorporate criticality which is at null spikes of theta rate (3-7 Hz) as onset of amplitude modulations with envelopes of gamma oscillations from one zero to another zero with gaps. We are analyzing the dynamics of zeroes establishing local equilibrium. We found gaps staying close to the global average gap size of whole electrodes toward a deeper understanding of the cone patterns. Those patterns over spatial scale is in the unique forms of a cone with synchronizations with phase modulations through null spikes zero times in EEG beta-gamma for healthy subjects and bipolar disorders. Gamma oscillations in the gamma range (30-80 Hz) of a spectral band which is a role of inhibitory feedback even whether implement causal mechanisms of functional roles of brain functions or represent a general dynamic mode of neural pathways is not well understood. Our method involves preprocessing steps such as de-meaning and finite impulse response (FIR) filtering based on 10-20 EEG electrodes, followed by Hilbert transform analysis and supremum of Banach p-norms in complex space mechanistically explaining energy and entropy. In this perspective, we analyzed in the study of theta-gamma oscillations toward a deeper understanding the evolution of theoretical Carnot to Rankine cycles under the backwards heat equation.