p. 153 of
- Raúl M. Falcón Ganfornina and Juan Núñez Valdés, “Mathematical Foundations of Santilli Isotopies,” trans. Alan Aversa, Algebras, Groups, and Geometries 32 (2015): 135–308.
quotes (but does not cite) Einstein saying that
without the discoveries of Lie, the Theory of Relativity would probably never have been born.
Did Einstein actually say this (or something similar)?
I can only find a few references to Sophus Lie in the Einstein Papers, and they are only in letters addressed to Einstein.