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I report on two new measures of the sudden change in the orbital period ($P$)across the nova eruption ($\Delta$P) and the steady period change in quiescence($\dot{P}$) for classical novae (CNe) RR Pic and HR Del, bringing a total ofsix such measures for CNe, all in a final report of my large and long observingprogram. The fractional changes ($\Delta$P/P) in parts-per-million (ppm) are-290.71$\pm$0.28 (QZ Aur), -472.1$\pm$4.8 (HR Del), -4.46$\pm$0.03 (DQ Her),+39.6$\pm$0.5 (BT Mon), -2003.7$\pm$0.9 (RR Pic), and -273$\pm$61 (V1017 Sgr).These results are in stark opposition to the Hibernation Model for theevolution of cataclysmic variables (CVs), which requires $\Delta$P/P$>$+1000ppm to get the required drop in the accretion rate to produce hibernation. TheHibernation Model cannot be salvaged in any way. My program has also measuredthe first long-term $\dot{P}$ for classical novae, with -2.84$\pm$0.22 (QZAur), +4.0$\pm$0.9 (HR Del), +0.00$\pm$0.02 (DQ Her), -2.3$\pm$0.1 (BT Mon),and +1.25$\pm$0.01 (RR Pic) in units of $10^{-11}$ days/cycle. These can bedirectly compared to the predictions of the Magnetic Braking Model, where thelong-term average $\dot{P}$ is a single universal function of $P$. The measuredvalues are +5.3, $-$94, 0.00, +6.9, and $-$190 times that predicted by themodel, so the predictions are always greatly wrong. Further, the effects of the$\Delta$P averaged over the eruption cycle are usually much larger than themagnetic braking effects. To get a realistic model of CV evolution, we must addthe physics of the $\Delta$P and $\dot{P}$ variations.

monthly notices of the royal astronomical society

Sudden and Steady Orbital Period Changes Across Six Classical Nova  Eruptions; The End of Hibernation and Two Serious Challenges for the Magnetic  Braking Model of Cataclysmic Variable Evolution