The author paraphrases "spacetime tells matter how to move, and matter tells spacetime how to curve". The torsion axiom extends this to "...and matter tells spa

The author paraphrases "spacetime tells matter how to move, and matter tells spacetime how to curve". The torsion axiom extends this to "...and matter tells spacetime how to curve and twist". The way he explains it makes it sound like an elegant way to complete the General Relativity hypothesis, which Einstein described as "the happiest thought of his life". If an axiom has a certain elegance about it, then perhaps a quantum theory of gravity without torsion is adding the complexity, not the other way around.