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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeAug 25th 2018
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded a word on spherical cones ([here](https://ncatlab.org/nlab/show/cone+(Riemannian+geometry)#SphericalCones)) <a href="https://ncatlab.org/nlab/revision/diff/cone+%28Riemannian+geometry%29/8">diff</a>, <a href="https://ncatlab.org/nlab/revision/cone+%28Riemannian+geometry%29/8">v8</a>, <a href="https://ncatlab.org/nlab/show/cone+%28Riemannian+geometry%29">current</a>

   added a word on spherical cones (here)

   diff, v8, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeOct 14th 2020
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded mentioning of this example: The [[metric cone over complex projective 3-space]] carries the [[mathematical structure|structure]] of a [[G2-manifold]] whose [[Riemannian metric]] is [[invariant]] under the canonical [[Sp(2)]] [[action]] by left-[[matrix multiplication]] on homomogeneous coordinates in $\mathbb{H}^2 \simeq_{\mathbb{R}} \mathbb{C}^4 \to \mathbb{C}P^3$ ([Byant-Salamon 89](metric+cone+over+complex+projective+3-space#BryantSalamon89), see also [Acharya-Bryant-Salamon 20](metric+cone+over+complex+projective 3-space#AcharyaBryantSalamon20)). <a href="https://ncatlab.org/nlab/revision/diff/cone+%28Riemannian+geometry%29/10">diff</a>, <a href="https://ncatlab.org/nlab/revision/cone+%28Riemannian+geometry%29/10">v10</a>, <a href="https://ncatlab.org/nlab/show/cone+%28Riemannian+geometry%29">current</a>

   added mentioning of this example:

   The metric cone over complex projective 3-space carries the structure of a G2-manifold whose Riemannian metric is invariant under the canonical Sp(2) action by left-matrix multiplication on homomogeneous coordinates in $\mathbb{H}^2 \simeq_{\mathbb{R}} \mathbb{C}^4 \to \mathbb{C}P^3$ (Byant-Salamon 89, see also [Acharya-Bryant-Salamon 20](metric+cone+over+complex+projective 3-space#AcharyaBryantSalamon20)).

   diff, v10, current

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeJan 26th 2021
   • PermaLink
   Author: Urs
   Format: MarkdownItexadded pointer to today's * Rong-Xin Miao, _Codimension-$n$ Holography for the Cones_ ([arXiv:2101.10031](https://arxiv.org/abs/2101.10031)) <a href="https://ncatlab.org/nlab/revision/diff/cone+%28Riemannian+geometry%29/12">diff</a>, <a href="https://ncatlab.org/nlab/revision/cone+%28Riemannian+geometry%29/12">v12</a>, <a href="https://ncatlab.org/nlab/show/cone+%28Riemannian+geometry%29">current</a>

   added pointer to today’s

   • Rong-Xin Miao, Codimension-$n$ Holography for the Cones (arXiv:2101.10031)

   diff, v12, current