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", "Hashtag": "as:Hashtag" } ], "id": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345", "type": "Note", "summary": null, "inReplyTo": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728541668069779", "published": "2025-06-22T18:57:23Z", "url": "https://mathstodon.xyz/@joshuagrochow/114728543436792345", "attributedTo": "https://mathstodon.xyz/users/joshuagrochow", "to": [ "https://www.w3.org/ns/activitystreams#Public" ], "cc": [ "https://mathstodon.xyz/users/joshuagrochow/followers" ], "sensitive": false, "atomUri": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345", "inReplyToAtomUri": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728541668069779", "conversation": "tag:mathstodon.xyz,2025-06-22:objectId=159602609:objectType=Conversation", "content": "<p>This is an example of amortized complexity and Strassen&#39;s &quot;asymptotic spectra&quot; (nice monograph by Zuiddam &amp; Wigderson: <a href=\"https://www.math.ias.edu/~avi/PUBLICATIONS/WigdersonZu_Final_Draft_Oct2023.pdf\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://www.</span><span class=\"ellipsis\">math.ias.edu/~avi/PUBLICATIONS</span><span class=\"invisible\">/WigdersonZu_Final_Draft_Oct2023.pdf</span></a>)</p><p>Strassen developed this to understand the <a href=\"https://mathstodon.xyz/tags/complexity\" class=\"mention hashtag\" rel=\"tag\">#<span>complexity</span></a> of matrix multiplication and <a href=\"https://mathstodon.xyz/tags/tensors\" class=\"mention hashtag\" rel=\"tag\">#<span>tensors</span></a>, but it turns out to also show up in a bunch of places:<br />- <a href=\"https://mathstodon.xyz/tags/Entropy\" class=\"mention hashtag\" rel=\"tag\">#<span>Entropy</span></a><br />- <a href=\"https://mathstodon.xyz/tags/Quantum\" class=\"mention hashtag\" rel=\"tag\">#<span>Quantum</span></a> information<br />- Shannon capacity of graphs<br />- Communication complexity <a href=\"https://en.wikipedia.org/wiki/Communication_complexity#Information_Complexity\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">en.wikipedia.org/wiki/Communic</span><span class=\"invisible\">ation_complexity#Information_Complexity</span></a><br />- Circuit complexity (Robere &amp; Zuiddam <a href=\"https://eccc.weizmann.ac.il/report/2021/035\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">eccc.weizmann.ac.il/report/202</span><span class=\"invisible\">1/035</span></a>)</p><p><a href=\"https://mathstodon.xyz/tags/math\" class=\"mention hashtag\" rel=\"tag\">#<span>math</span></a> <a href=\"https://mathstodon.xyz/tags/probability\" class=\"mention hashtag\" rel=\"tag\">#<span>probability</span></a> <a href=\"https://mathstodon.xyz/tags/ComputationalComplexity\" class=\"mention hashtag\" rel=\"tag\">#<span>ComputationalComplexity</span></a> <a href=\"https://mathstodon.xyz/tags/TCS\" class=\"mention hashtag\" rel=\"tag\">#<span>TCS</span></a> <a href=\"https://mathstodon.xyz/tags/InformationTheory\" class=\"mention hashtag\" rel=\"tag\">#<span>InformationTheory</span></a></p>", "contentMap": { "en": "<p>This is an example of amortized complexity and Strassen&#39;s &quot;asymptotic spectra&quot; (nice monograph by Zuiddam &amp; Wigderson: <a href=\"https://www.math.ias.edu/~avi/PUBLICATIONS/WigdersonZu_Final_Draft_Oct2023.pdf\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://www.</span><span class=\"ellipsis\">math.ias.edu/~avi/PUBLICATIONS</span><span class=\"invisible\">/WigdersonZu_Final_Draft_Oct2023.pdf</span></a>)</p><p>Strassen developed this to understand the <a href=\"https://mathstodon.xyz/tags/complexity\" class=\"mention hashtag\" rel=\"tag\">#<span>complexity</span></a> of matrix multiplication and <a href=\"https://mathstodon.xyz/tags/tensors\" class=\"mention hashtag\" rel=\"tag\">#<span>tensors</span></a>, but it turns out to also show up in a bunch of places:<br />- <a href=\"https://mathstodon.xyz/tags/Entropy\" class=\"mention hashtag\" rel=\"tag\">#<span>Entropy</span></a><br />- <a href=\"https://mathstodon.xyz/tags/Quantum\" class=\"mention hashtag\" rel=\"tag\">#<span>Quantum</span></a> information<br />- Shannon capacity of graphs<br />- Communication complexity <a href=\"https://en.wikipedia.org/wiki/Communication_complexity#Information_Complexity\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">en.wikipedia.org/wiki/Communic</span><span class=\"invisible\">ation_complexity#Information_Complexity</span></a><br />- Circuit complexity (Robere &amp; Zuiddam <a href=\"https://eccc.weizmann.ac.il/report/2021/035\" target=\"_blank\" rel=\"nofollow noopener noreferrer\" translate=\"no\"><span class=\"invisible\">https://</span><span class=\"ellipsis\">eccc.weizmann.ac.il/report/202</span><span class=\"invisible\">1/035</span></a>)</p><p><a href=\"https://mathstodon.xyz/tags/math\" class=\"mention hashtag\" rel=\"tag\">#<span>math</span></a> <a href=\"https://mathstodon.xyz/tags/probability\" class=\"mention hashtag\" rel=\"tag\">#<span>probability</span></a> <a href=\"https://mathstodon.xyz/tags/ComputationalComplexity\" class=\"mention hashtag\" rel=\"tag\">#<span>ComputationalComplexity</span></a> <a href=\"https://mathstodon.xyz/tags/TCS\" class=\"mention hashtag\" rel=\"tag\">#<span>TCS</span></a> <a href=\"https://mathstodon.xyz/tags/InformationTheory\" class=\"mention hashtag\" rel=\"tag\">#<span>InformationTheory</span></a></p>" }, "updated": "2025-06-22T18:59:42Z", "attachment": [], "tag": [ { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/informationtheory", "name": "#informationtheory" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/tcs", "name": "#tcs" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/ComputationalComplexity", "name": "#ComputationalComplexity" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/probability", "name": "#probability" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/math", "name": "#math" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/quantum", "name": "#quantum" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/entropy", "name": "#entropy" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/tensors", "name": "#tensors" }, { "type": "Hashtag", "href": "https://mathstodon.xyz/tags/complexity", "name": "#complexity" } ], "replies": { "id": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345/replies", "type": "Collection", "first": { "type": "CollectionPage", "next": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345/replies?only_other_accounts=true&page=true", "partOf": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345/replies", "items": [] } }, "likes": { "id": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345/likes", "type": "Collection", "totalItems": 0 }, "shares": { "id": "https://mathstodon.xyz/users/joshuagrochow/statuses/114728543436792345/shares", "type": "Collection", "totalItems": 1 } }