👁️ 🌹 💨 💨

Comments

• lugal@lemmy.dbzer0.com ⁨3⁩ ⁨weeks⁩ ago

  Color is a social construct

  source

  • JackGreenEarth@lemm.ee ⁨3⁩ ⁨weeks⁩ ago

    Well, the names for different parts of the color spectrum are, I suppose. Wavelength of EM radiation, and how your brain interprets it as color, is ‘real’.

    source

    • tate@lemmy.sdf.org ⁨3⁩ ⁨weeks⁩ ago

      I think they were alluding to a different use of the word color.

      source

      • -> View More Comments
    • rambling_lunatic@sh.itjust.works ⁨3⁩ ⁨weeks⁩ ago

      This technically goes down a very interesting line of thought that Vsauce covered once.

      source
• noodles@sh.itjust.works ⁨3⁩ ⁨weeks⁩ ago

  OK I need someone to explain this to me Cause AFAIK light speed is constant no matter how fast moving the source is

  source

  • gnutrino@programming.dev ⁨3⁩ ⁨weeks⁩ ago

    Light speed is constant but the apparent frequency and wavelength (which roughly corresponds to what colour we see) change due to the Doppler effect

    source

    • Track_Shovel@slrpnk.net ⁨3⁩ ⁨weeks⁩ ago

      Fascinating

      source

      • -> View More Comments
  • captainlezbian@lemmy.world ⁨3⁩ ⁨weeks⁩ ago

    So light is a wave. Shorter wavelengths are bluer longer wavelengths are redder. When you walk towards a wave you hit the peaks and troughs faster than had you been still. They come slower if you’re walking away from it. The Doppler effect is that but with light waves and velocities that make it relevant

    source
  • bjoern_tantau@swg-empire.de ⁨3⁩ ⁨weeks⁩ ago

    Which is achieved by spacetime dilation which can in turn stretch or compress the light waves.

    source

    • BB84@mander.xyz ⁨3⁩ ⁨weeks⁩ ago

      While it is true that space time dilation can cause red/blueshift, that is a distinct from the doppler effect which is the primary effect here.

      (dilation plays only a small role: without time dilation our answer going from 700nm to 350nm would be 0.5c instead of the 0.6c calculated below)

      source
  • Skalix@lemmy.world ⁨3⁩ ⁨weeks⁩ ago

    Adding to the other comments; I once saw a interesting video of a visual demonstration of that effect and other weird things that happen close to the speed of light. It was this one if i remember correctly: www.youtube.com/watch?v=ge_j31Yx_yk

    source
• TheSlad@sh.itjust.works ⁨3⁩ ⁨weeks⁩ ago

  How fast would the rose have to be going to blueshift that much? Someone please do the math

  source

  • itslilith@lemmy.blahaj.zone ⁨3⁩ ⁨weeks⁩ ago

    For a shift from about 700nm to 350nm: coming right at you at 0.6c

    It would also have a kinetic energy of about 1.1234 Petajoules, on the order of magnitude of the Tsar Bomba

    source

    • BB84@mander.xyz ⁨3⁩ ⁨weeks⁩ ago

      Kinetic energy or total energy? Assuming the rose weight 10 grams I get that much total energy, but only 0.225PJ is kinetic.

      source

      • -> View More Comments
  • vrek@programming.dev ⁨3⁩ ⁨weeks⁩ ago

    I don’t know about blue but here is all the math to turn a red light green… Don’t think of doing it though while you could probably get out of a ticket for running a red light I don’t even know what the fine is for driving many thousand times the speed limit is.

    source

    • itslilith@lemmy.blahaj.zone ⁨3⁩ ⁨weeks⁩ ago

      To bad the traffic light is in the speed radar’s reference frame, when your licence plate is on the photo I doubt the judge will care that your yellow car is clearly blue on the photo

      source

      • -> View More Comments
  • FleetingTit@feddit.org ⁨3⁩ ⁨weeks⁩ ago

    60% of lightspeed, according to another commenter.

    source
  • tacosanonymous@lemm.ee ⁨3⁩ ⁨weeks⁩ ago

    Impossibly fast and it would have to becoming right at us.

    source
• Sam_Bass@lemmy.world ⁨3⁩ ⁨weeks⁩ ago

  Speed chills

  source

  • andrew_bidlaw@sh.itjust.works ⁨3⁩ ⁨weeks⁩ ago

    Speed kills coming down the mountain Speed kills, coming down the street Speed kills with presence of mind Speed kills, if you know what I mean

    source
• itslilith@lemmy.blahaj.zone ⁨3⁩ ⁨weeks⁩ ago

  Image

  source