How Long Does a Torsion Bounce Accelerate? Duration and Expansion of the Accelerating Window as a Function of Equation of State

For dust the accelerating window opens at a density fraction r = 0.250 of the bounce density and lasts 2.309 bounce timescales in total across both branches, accumulating 0.462 e-folds of expansion on the expanding side. For radiation the duration is 1.414 bounce timescales. For stiff matter the window opens only at r = 0.400, lasts 0.816 bounce timescales, and accumulates 0.153 e-folds on the expanding side. The trend across the scan is monotone and unsurprising in retrospect: softer equations of state open the window earlier, at lower density, and keep it open longer, because the effective pressure term that must be overcome is smaller. Even in the most favourable case, however, the expansion accumulated inside the window is a small fraction of one e-fold. The study is a computation from stated assumptions, performed by the accompanying script; it is simulated, not measured.