Geography is four-dimensional(sive.rs)
35 pointsby galfarragem4 hours ago5 comments
  • admiralrohan2 hours ago
    Same is true for humans too. About their personality. Constantly changing and you will never meet the same person twice in that sense.
    • finghin2 hours ago
      Dubious given Brouwer’s Fixed Point Theorem;)
  • coder97an hour ago
    I resonate with the first paragraph. Those people raised with beliefs of a time that does not exist anymore happen to be very conservative and refuse to see the change.
  • roywiggins2 hours ago
    “The past is a foreign country; they do things differently there.”
  • pella3 hours ago
    Every geography has a timestamp.
  • soco3 hours ago
    I get the latitude, longitude, and they added time. But what was the fourth dimension? Or third rather, because the post assumption is that time was the fourth added.
    • deweller3 hours ago
      Altitude is the third dimension, but I presume you knew that.

      "Geography is three dimensional" doesn't correctly communicate the time dimension.

      • ySteeK2 hours ago
        Even with altitude, you still need time. The Earth moves around the Sun, the Sun around the galactic center, all at hundreds of km/s. Without a timestamp, lat/long/alt just tells you where something was, not where it is. Time was never optional.
      • marginalia_nuan hour ago
        You can model geography as a 2D heightmap to a pretty good approximation tbh.
        • dibujaronan hour ago
          a heightmap is three-dimensional, where the third dimension is usually represented with color or contour lines.
          • marginalia_nu13 minutes ago
            A mathematically ideal sheet of paper in a 3d-dimensional space can be addressed with both 2D coordinates, within the reference frame of the paper, and 3D coordinates, within the 3D space, but given that the paper has a location in space, 2D coordinates are sufficient to specify a point in 3D space.

            You can do the same with geography. It's why generally only specify geographical coordinates with latitude and longitude, altitude is a given from those two, since you're as unlikely to be hovering in the air as you are to be immersed in bedrock.

      • soco2 hours ago
        Hmm I thought that, but we don't really live in a 3D world (or use the altitude parameter in a very meaningful way in life) so I wondered whether there's something else I was missing.
        • notachatbot1232 hours ago
          I wonder what makes you belittle the altitude dimension? Buildings have storys, humans can sit and stand, birds can fly, your eyes can move up and down your monitor.
          • zimpenfishan hour ago
            Also the altitude of a given lat/long can change due to geological processes, climate processes, war, etc.
    • incognito1242 hours ago
      The lat and lon are actually 3d since we live, up to a first approximation, on the surface of a sphere. The correct way to think about it is xyz in a reference frame anchored in the center of the Earth
      • finghin2 hours ago
        If you accepted that nothing exists at the north pole, that’s enough to obtain meaningful 2d coordinates for a location:)

        Not workable in practice, though!

    • JNORLINan hour ago
      The fourth is altitude. I asked a colleague how he found Vietnam. I was surprised to hear him say it said it was windy, desolate, and cold as hell. It did not match my experience at all. Turns out he had been hanging out at 30 000 feet the whole time!
    • 2 hours ago
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