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arXiv · 2311.02054

The Poincar\'e pear and Poincar\'e-Darwin fission theory in astrophysics, 1885-1901

Scott A. Walter
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Abstract

In the early 1880s, Henri Poincar\'e discovered a new equilibrium figure for uniformly-rotating fluid masses -- the pear, or piriform figure -- and speculated that in certain circumstances the pear splits into two unequal parts, and provides thereby a model for the origin of binary stars. The contemporary emergence of photometric and spectroscopic studies of variable stars fueled the first models of eclipsing binaries, and provided empirical support for a realist view of equilibrium figures -- including the pear -- in the cosmic realm. The paper reviews astrophysical interpretation of the Poincar\'e pear and the Poincar\'e-Darwin fission hypothesis with respect to research on variable stars from 1885 to 1901.

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Scott A. Walter. 2023-11-03. The Poincar\'e pear and Poincar\'e-Darwin fission theory in astrophysics, 1885-1901. https://doi.org/10.4000/philosophiascientiae.4178

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