observantTrapezium

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Joined 1 year ago
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Cake day: June 30th, 2023

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  • Not sure this statement is true if “more closely related” is understood as shorter combined time between the two species from their most recent common ancestor. Hummingbirds and brachiosaurs had a more recent common ancestor than brachiosaurs and triceratopses (albeit probably still quite close to the dawn of dinosaurs in the Late Triassic ), but the latter pair lived closer in time to the common ancestor of all dinosaurs (while hummingbirds are from the Oligocene).












  • observantTrapezium@lemmy.catoScience Memes@mander.xyzSeconds
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    2 months ago

    That may be relativists (they would actually measure anything in units of mass, with everything else defined through G = c = 1). Astrophysicists commonly measure mass in solar masses, long distances in parsec (or kiloparsec, megaparsec), short distances in solar radii or AU, and time in whatever is relevant to their problem (could be seconds or gigayears)


  • I’m sitting on an Aeron at work, it’s good, but I can’t in good conscience pay that much for a chair. I was recently on the market for a new office chair and extensively researched it. It really looks like it’s a hit or miss with every chair in every price range, and I was very seriously considering replacing my Hyken with another Hyken. I decided to go with the IKEA Markus and have been sitting on it for about a month. I’m only moderately happy with it, may even return it before the year is up although I’d hate doing it.






  • EM and gravitational waves are seen as analogous because as I wrote, they are produced by acceleration of charges and masses, respectively. The physics behind them is very different (described by Maxwell’s equations for EM and Einstein field equations for GW), but all systems that have waves in them (including sound in the air, waves on the surface of water etc.) can be approximated as linear for small perturbations, which means that they satisfy the wave equation at that regime.