ActivityPub Viewer

A small tool to view real-world ActivityPub objects as JSON! Enter a URL or username from Mastodon or a similar service below, and we'll send a request with the right Accept header to the server to view the underlying object.

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{ "@context": [ "https://www.w3.org/ns/activitystreams", { "ostatus": "http://ostatus.org#", "atomUri": "ostatus:atomUri", "inReplyToAtomUri": "ostatus:inReplyToAtomUri", "conversation": "ostatus:conversation", "sensitive": "as:sensitive", "toot": "http://joinmastodon.org/ns#", "votersCount": "toot:votersCount", "blurhash": "toot:blurhash", "focalPoint": { "@container": "@list", "@id": "toot:focalPoint" }, "Hashtag": "as:Hashtag" } ], "id": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863", "type": "Note", "summary": null, "inReplyTo": null, "published": "2024-10-05T08:32:23Z", "url": "https://mathstodon.xyz/@OscarCunningham/113253885108835863", "attributedTo": "https://mathstodon.xyz/users/OscarCunningham", "to": [ "https://www.w3.org/ns/activitystreams#Public" ], "cc": [ "https://mathstodon.xyz/users/OscarCunningham/followers" ], "sensitive": false, "atomUri": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863", "inReplyToAtomUri": null, "conversation": "tag:mathstodon.xyz,2024-10-05:objectId=117442890:objectType=Conversation", "content": "<p><a href=\"https://mathstodon.xyz/tags/Mathober\" class=\"mention hashtag\" rel=\"tag\">#<span>Mathober</span></a> <a href=\"https://mathstodon.xyz/tags/Mathober2024\" class=\"mention hashtag\" rel=\"tag\">#<span>Mathober2024</span></a></p><p>The prompt for day 4 was &#39;Form&#39;. In algebra, a multilinear map is a function from several vector spaces to another vector space which is linear in each argument. Just as a linear map can be represented by a grid of numbers in a matrix, a multilinear map can be represented by a multidimensional grid of numbers: a tensor. A &#39;form&#39; is the function you get by taking a multilinear map from V×...×V to the scalars and evaluating it with each of its arguments the same. In this way you get a *non*linear map from V to the scalars.</p><p>The image shows a degree 50 form on ℝ³ evaluated on the unit sphere. The form was randomly chosen with each of the 3⁵⁰ entries in its tensor having a standard normal distribution. </p><p><a href=\"https://mathstodon.xyz/tags/Math\" class=\"mention hashtag\" rel=\"tag\">#<span>Math</span></a> <a href=\"https://mathstodon.xyz/tags/Maths\" class=\"mention hashtag\" rel=\"tag\">#<span>Maths</span></a> <a href=\"https://mathstodon.xyz/tags/Mathematics\" class=\"mention hashtag\" rel=\"tag\">#<span>Mathematics</span></a> <a href=\"https://mathstodon.xyz/tags/Algebra\" class=\"mention hashtag\" rel=\"tag\">#<span>Algebra</span></a></p>", "contentMap": { "en": "<p><a href=\"https://mathstodon.xyz/tags/Mathober\" class=\"mention hashtag\" rel=\"tag\">#<span>Mathober</span></a> <a href=\"https://mathstodon.xyz/tags/Mathober2024\" class=\"mention hashtag\" rel=\"tag\">#<span>Mathober2024</span></a></p><p>The prompt for day 4 was &#39;Form&#39;. In algebra, a multilinear map is a function from several vector spaces to another vector space which is linear in each argument. Just as a linear map can be represented by a grid of numbers in a matrix, a multilinear map can be represented by a multidimensional grid of numbers: a tensor. A &#39;form&#39; is the function you get by taking a multilinear map from V×...×V to the scalars and evaluating it with each of its arguments the same. In this way you get a *non*linear map from V to the scalars.</p><p>The image shows a degree 50 form on ℝ³ evaluated on the unit sphere. The form was randomly chosen with each of the 3⁵⁰ entries in its tensor having a standard normal distribution. </p><p><a href=\"https://mathstodon.xyz/tags/Math\" class=\"mention hashtag\" rel=\"tag\">#<span>Math</span></a> <a href=\"https://mathstodon.xyz/tags/Maths\" class=\"mention hashtag\" rel=\"tag\">#<span>Maths</span></a> <a href=\"https://mathstodon.xyz/tags/Mathematics\" class=\"mention hashtag\" rel=\"tag\">#<span>Mathematics</span></a> <a href=\"https://mathstodon.xyz/tags/Algebra\" class=\"mention hashtag\" rel=\"tag\">#<span>Algebra</span></a></p>" }, "attachment": [ { "type": "Document", "mediaType": "image/png", "url": "https://media.mathstodon.xyz/media_attachments/files/113/253/883/462/601/532/original/623141aabd5e36b9.png", "name": "A blue sphere with dark and light splotches.", "blurhash": "U4DJ*bx]DQWA%gt7WAafVxM{kB%g8wRQ%foz", "focalPoint": [ 0, 0 ], "width": 420, "height": 420 } ], "tag": [ { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/algebra", "name": "#algebra" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/mathematics", "name": "#mathematics" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/maths", "name": "#maths" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/math", "name": "#math" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/mathober2024", "name": "#mathober2024" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/mathober", "name": "#mathober" } ], "replies": { "id": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863/replies", "type": "Collection", "first": { "type": "CollectionPage", "next": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863/replies?only_other_accounts=true&page=true", "partOf": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863/replies", "items": [] } }, "likes": { "id": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863/likes", "type": "Collection", "totalItems": 9 }, "shares": { "id": "https://mathstodon.xyz/users/OscarCunningham/statuses/113253885108835863/shares", "type": "Collection", "totalItems": 3 } }