{"id":209,"date":"2010-02-28T13:56:50","date_gmt":"2010-02-28T18:56:50","guid":{"rendered":"http:\/\/blog.carlrobitaille.org\/?p=209"},"modified":"2010-02-28T13:56:50","modified_gmt":"2010-02-28T18:56:50","slug":"energy-is-not-conserved","status":"publish","type":"post","link":"https:\/\/blog.carlrobitaille.org\/?p=209","title":{"rendered":"Energy Is Not Conserved"},"content":{"rendered":"<p><a href=\"http:\/\/blogs.discovermagazine.com\/cosmicvariance\/2010\/02\/22\/energy-is-not-conserved\/?utm_source=feedburner&#038;utm_medium=feed&#038;utm_campaign=Feed%3A+CosmicVarianceBlog+%28Cosmic+Variance%29\">Energy Is Not Conserved<\/a><\/p>\n<blockquote><p>The point is pretty simple: back when you thought energy was conserved, there was a reason why you thought that, namely time-translation invariance. A fancy way of saying \u201cthe background on which particles and forces evolve, as well as the dynamical rules governing their motions, are fixed, not changing with time.\u201d But in general relativity that\u2019s simply no longer true. Einstein tells us that space and time are dynamical, and in particular that they can evolve with time. When the space through which particles move is changing, the total energy of those particles is not conserved.<\/p><\/blockquote>\n","protected":false},"excerpt":{"rendered":"<p>Energy Is Not Conserved The point is pretty simple: back when you thought energy was conserved, there was a reason why you thought that, namely time-translation invariance. A fancy way of saying \u201cthe background on which particles and forces evolve, &hellip; <a href=\"https:\/\/blog.carlrobitaille.org\/?p=209\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[29],"tags":[],"class_list":["post-209","post","type-post","status-publish","format-standard","hentry","category-physique"],"_links":{"self":[{"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=\/wp\/v2\/posts\/209","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=209"}],"version-history":[{"count":1,"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=\/wp\/v2\/posts\/209\/revisions"}],"predecessor-version":[{"id":210,"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=\/wp\/v2\/posts\/209\/revisions\/210"}],"wp:attachment":[{"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=209"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=209"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.carlrobitaille.org\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=209"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}