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2-category 2-category-theory abelian-categories adjoint algebra algebraic algebraic-geometry algebraic-topology analysis analytic-geometry arithmetic arithmetic-geometry book bundles calculus categorical categories category category-theory chern-weil-theory cohesion cohesive-homotopy-type-theory cohomology colimits combinatorics complex complex-geometry computable-mathematics computer-science constructive cosmology definitions deformation-theory descent diagrams differential differential-cohomology differential-equations differential-geometry digraphs duality elliptic-cohomology enriched fibration foundation foundations functional-analysis functor gauge-theory gebra geometric-quantization geometry graph graphs gravity grothendieck group group-theory harmonic-analysis higher higher-algebra higher-category-theory higher-differential-geometry higher-geometry higher-lie-theory higher-topos-theory homological homological-algebra homotopy homotopy-theory homotopy-type-theory index-theory integration integration-theory k-theory lie-theory limits linear linear-algebra locale localization logic mathematics measure-theory modal modal-logic model model-category-theory monad monads monoidal monoidal-category-theory morphism motives motivic-cohomology nforum nlab noncommutative noncommutative-geometry number-theory of operads operator operator-algebra order-theory pages pasting philosophy physics pro-object probability probability-theory quantization quantum quantum-field quantum-field-theory quantum-mechanics quantum-physics quantum-theory question representation representation-theory riemannian-geometry scheme schemes set set-theory sheaf simplicial space spin-geometry stable-homotopy-theory stack string string-theory superalgebra supergeometry svg symplectic-geometry synthetic-differential-geometry terminology theory topology topos topos-theory tqft type type-theory universal variational-calculus

1. • CommentRowNumber1.
   • CommentAuthorTim_Porter
   • CommentTimeNov 8th 2010
   • PermaLink
   Author: Tim_Porter
   Format: MarkdownItex>Someone should improve this article so that it gives a definition of ‘algebraic theory’ before considering special cases such as ‘commutative algebraic theory’. Thus is the current end to the entry on [[algebraic theory]] and I agree. Further I needed FP theory or FP sketch for something so looked at [[sketch]]. That looks as if it needs a bit of TLC as well, well not this afternoon as I have some other things that need doing. I did add the link to Barr and Wells, to [[sketch]], however as this is now freely available as a TAC reprint.

   Someone should improve this article so that it gives a definition of ‘algebraic theory’ before considering special cases such as ‘commutative algebraic theory’.

   Thus is the current end to the entry on algebraic theory and I agree. Further I needed FP theory or FP sketch for something so looked at sketch. That looks as if it needs a bit of TLC as well, well not this afternoon as I have some other things that need doing. I did add the link to Barr and Wells, to sketch, however as this is now freely available as a TAC reprint.

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeNov 8th 2010
   • PermaLink
   Author: Urs
   Format: MarkdownItex> and I agree Me, too. On the other hand, notice that the entry [[Lawvere theory]] is considerably further developed.

   and I agree

   Me, too. On the other hand, notice that the entry Lawvere theory is considerably further developed.

3. • CommentRowNumber3.
   • CommentAuthorTim_Porter
   • CommentTimeNov 8th 2010
   • PermaLink
   Author: Tim_Porter
   Format: MarkdownItexThe usual convention seems to be that Lawvere theories are generated by a single object, so are 'single sorted'. I need many sorted ones. Perhaps the redirect on [[algebras for an algebraic theory]] is not optimal. We can change it once there is a bit more meat in some of the relevant entries.

   The usual convention seems to be that Lawvere theories are generated by a single object, so are ’single sorted’. I need many sorted ones. Perhaps the redirect on algebras for an algebraic theory is not optimal. We can change it once there is a bit more meat in some of the relevant entries.

4. • CommentRowNumber4.
   • CommentAuthorUrs
   • CommentTimeNov 8th 2010
   • PermaLink
   Author: Urs
   Format: MarkdownItexYes, agreed. Eventually all this should be improved.

   Yes, agreed. Eventually all this should be improved.

5. • CommentRowNumber5.
   • CommentAuthorTim_Porter
   • CommentTimeNov 8th 2010
   • (edited Nov 8th 2010)
   • PermaLink
   Author: Tim_Porter
   Format: MarkdownItexI was thinking of adapting stuff from Makkai and Paré on accessibility as it has a short intro to sketches, and then also to put in some thoughts on Toposes, Triples and Theories. (Perhaps a TOC for that book could be added somewhere. I will try to do it tonight. TAC did a reprint.) (Edit later: Done the entry. A very stubby and the TOC is not elegantly formatted)

   I was thinking of adapting stuff from Makkai and Paré on accessibility as it has a short intro to sketches, and then also to put in some thoughts on Toposes, Triples and Theories. (Perhaps a TOC for that book could be added somewhere. I will try to do it tonight. TAC did a reprint.)

   (Edit later: Done the entry. A very stubby and the TOC is not elegantly formatted)