Why did Einstein Reject the November Tensor in 1912-1913, only to Come Back to it in November 1915?

TL;DR

This paper re-examines Einstein's changing views on the November tensor between 1912 and 1915, analyzing historical interpretations and proposing a new understanding of his reasoning process.

Contribution

It offers a new combined conjecture explaining Einstein's initial rejection and later acceptance of the November tensor, clarifying his conceptual development.

Findings

Einstein initially rejected the November tensor in 1912.

He recognized it as a natural generalization of Newton's law by 1915.

A new conjecture explains the delayed recognition of the tensor's significance.

Abstract

The question of Einstein's rejection of the November tensor is re-examined in light of conflicting answers by several historians. I discuss these conflicting conjectures in view of three questions that should inform our thinking: Why did Einstein reject the November tensor in 1912, only to come back to it in 1915? Why was it hard for Einstein to recognize that the November tensor is a natural generalization of Newton's law of gravitation? Why did it take him three years to realize that the November tensor is not incompatible with Newton's law? I first briefly describe Einstein's work in the Zurich Notebook. I then discuss a number of interpretive conjectures formulated by historians and what may be inferred from them. Finally, I offer a new combined conjecture that answers the above questions.