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Dear Michael, thanks for your comment. I made the comment about the old version of the article almost exactly 3 years ago, see the version at that time: . It said ""Einstein–Cartan theory in theoretical physics extends general relativity, to handle spin angular momentum correctly."" at the very beginning and the whole article was written in the spirit of the claim that general relativity (without extensions) describes the spin incorrectly. As far as I can read, this is no longer claimed by the article. Einstein-Cartan theory is a historically important extension of general relativity, with some extra fields (torsion), but all the modern evidence indicates that such extra fields don't exist - and they're not needed. If you care about sociology, no research of cosmology or calculations of NASA's experiments or anything of the sort takes the ""torsion field"" into account because the latter doesn't exist, as far as the existing evidence - theoretical or experimental - can say. Today, it's not an important proposal to extend GR. The new article doesn't make these points too clear but at least it also no longer makes crazy claims throughout the text that general relativity (without torsion) is inconsistent with the spin, or something like that, so I wouldn't protest against the new version. Visually, it surely looks like a well-written article. However, I see some confusion in your comment that does show that the articles doesn't explain the basic points too clearly. Einstein-Cartan theory is not ""just"" about the tetrads. Tetrads are indeed useful - and in some formal sense necessary - to describe spin in General Relativity. However, using the tetrads formalism is not yet Einstein-Cartan theory. Einstein-Cartan theory assumes that ""torsion"" may be nonzero - even though it is identically zero in general relativity (which normally uses the metric). One can write GR in terms of tetrads as well - and the torsion is still zero. If that's so, one isn't doing Einstein-Cartan theory.   "