2025-05-17T23:59:33Z https://yabu.me StartsWithABang https://yabu.me/npub10lrmkc8f3n0weck6scz3eene9d38nvz6hefdmmm06ef40qsgv0jsfnnszn https://media.astrodon.social/accounts/avatars/109/423/548/510/866/031/original/ac5e27348092958d.jpg https://media.astrodon.social/accounts/avatars/109/423/548/510/866/031/original/ac5e27348092958d.jpg https://yabu.me/nevent1qqsrtjepgvc2jqeug8wl5vtgjdhgzglgmhpr5c36kk73gz6e0u96rnszyplu0wmqaxxdam8zm2rq288x0y4ky7dst2l99h00dlt9x4uzpp372frg9m9 In reply to <a href='/nevent1qqs2tkx44skmxcnedwgex65uu2d0gg3kun77ntnc05hy5r7hnteyl5stawvhr'>nevent1q…wvhr</a><br/>_________________________<br/><br/>Energy is conserved in all GR solutions that possess a time-like Killing vector. (I.e., in static, non-expanding, non-contracting spacetimes.)<br/><br/>Schwarzschild and Kerr metrics have these vectors, and therefore there is global energy conservation in those spacetimes.<br/><br/>Also, there are still energy conditions (e.g., the null energy condition) that ought to hold even in non-energy-conserving spacetimes, which is why we can&#39;t just keep pulling things out of the quantum vacuum for free.<br/><br/>But John will understand these issues more deeply than I do, if what I&#39;ve posted here isn&#39;t enough (or isn&#39;t rigorously true). 2025-05-20T17:04:33Z https://yabu.me/nevent1qqsdz0k93x4z472uunpy5808xjvwsm8vmqghcyfyzx8lv7w0hshuzqqzyplu0wmqaxxdam8zm2rq288x0y4ky7dst2l99h00dlt9x4uzpp372glk2na In reply to <a href='/nevent1qqsxdg8w0uywgsjpnvxqq2hry7crn29ft9rjg9m0qzspwj7tm36xrksj9u0mt'>nevent1q…u0mt</a><br/>_________________________<br/><br/>So, let&#39;s pretend we lived in a world where instead of me being an astrophysicist who became a science communicator, I (or someone like me) was a condensed matter physicist who became a science communicator.<br/><br/>How should I be communicating the notions of states of matter (and/or phases of matter) to the general public?<br/><br/>What don&#39;t they know; what should they know; how should they think about it?<br/><br/>How do you convey &#34;there are X different phases of superfluidity in different isotopes of helium&#34; or &#34;Y different phases of water-ice in solid form&#34; or &#34;every phase transition yields a new state of matter&#34; without rendering everyday concepts of what a &#34;phase&#34; or &#34;state&#34; of matter is untenable?<br/><br/>In biology, we have many different granularities of classification for organism, from superkingdom to subspecies. Do we need something like that for states of matter? And what would it look like?<br/><br/>I&#39;m legitimately not enough of an expert to have a strong opinion. What&#39;s yours? 2025-03-08T15:15:49Z https://yabu.me/nevent1qqs04c4dhte8tha2t9pvhggqh6nmjaafpmxuypm35yg5yt4lxcll0hgzyplu0wmqaxxdam8zm2rq288x0y4ky7dst2l99h00dlt9x4uzpp3729yjn6a The Ring Nebula’s true structure revealed at last<br/><br/>For nearly 250 years, astronomers have marveled at the Ring Nebula.<br/><br/>At long last, we know its true shape, and while it does possess a ring, it truly is so much more.<br/><br/><a href="https://bigthink.com/starts-with-a-bang/ring-nebula-true-structure-revealed/">https://bigthink.com/starts-with-a-bang/ring-nebula-true-structure-revealed/</a><br/> <img src="https://media.astrodon.social/media_attachments/files/113/861/621/868/073/726/original/212ba3c37ec8576f.jpg"> <br/> 2025-01-20T16:28:56Z https://yabu.me/nevent1qqsyesze0f2jr9h8juwp4263x47rukk57z648yuzl8wpyk23y9yp0zgzyplu0wmqaxxdam8zm2rq288x0y4ky7dst2l99h00dlt9x4uzpp37229nwgk In reply to <a href='/nevent1qqszqq6dulm7qkdx5w49cja5mfsq8nkwa90u7yyyv0st9n6732ra8ds60gvqg'>nevent1q…gvqg</a><br/>_________________________<br/><br/>Lovely! I am a big fan of creative cooking and this is the opposite of the turducken I made 16 years ago: reducing the turkey to its constituent parts instead of adding additional birds inside of it! 2024-11-20T18:51:14Z https://yabu.me/nevent1qqswjd76nehf2md2caafgwd3ufs92maqk7g6s8l629uee73udp6gf6szyplu0wmqaxxdam8zm2rq288x0y4ky7dst2l99h00dlt9x4uzpp372qmaj7r What happens if you deep fry a frozen turkey?<br/><br/>It&#39;s that time of year once again: where 46 million turkeys are about to be cooked, and 1000+ home fires are anticipated.<br/><br/>Don&#39;t be one of them, and especially don&#39;t deep fry a frozen turkey!<br/><br/><a href="https://bigthink.com/starts-with-a-bang/what-happens-deep-fry-frozen-turkey/">https://bigthink.com/starts-with-a-bang/what-happens-deep-fry-frozen-turkey/</a><br/> <img src="https://media.astrodon.social/media_attachments/files/113/516/635/789/654/434/original/0df571a673c328f8.jpg"> <br/> 2024-11-20T18:13:22Z