okr765
  • Communities
  • Create Post
  • Create Community
  • heart
    Support Lemmy
  • search
    Search
  • Login
  • Sign Up
BB84@mander.xyz to Science Memes@mander.xyzEnglish · 9 months ago

👁️ 🌹 💨 💨

lemmy.ml

message-square
30
fedilink
1.15K

👁️ 🌹 💨 💨

lemmy.ml

BB84@mander.xyz to Science Memes@mander.xyzEnglish · 9 months ago
message-square
30
fedilink

cross-posted from: https://lemmy.ml/post/19504984

It’s all relative

alert-triangle
You must log in or register to comment.
  • lugal@lemmy.dbzer0.com
    link
    fedilink
    English
    arrow-up
    31
    ·
    9 months ago

    Color is a social construct

    • JackGreenEarth@lemm.ee
      link
      fedilink
      English
      arrow-up
      35
      ·
      9 months 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’.

      • tate@lemmy.sdf.org
        link
        fedilink
        English
        arrow-up
        3
        ·
        9 months ago

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

        • JackGreenEarth@lemm.ee
          link
          fedilink
          English
          arrow-up
          2
          ·
          9 months ago

          What use? The only thing I can think of is ‘colourful’ language, which doesn’t seem to really make sense in this context.

          • tate@lemmy.sdf.org
            link
            fedilink
            English
            arrow-up
            2
            ·
            9 months ago

            “People of color.”

      • rambling_lunatic@sh.itjust.works
        link
        fedilink
        English
        arrow-up
        1
        ·
        9 months ago

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

  • noodles@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    21
    arrow-down
    1
    ·
    edit-2
    9 months ago

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

    • gnutrino@programming.dev
      link
      fedilink
      English
      arrow-up
      52
      ·
      9 months 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

      • Track_Shovel@slrpnk.net
        link
        fedilink
        English
        arrow-up
        11
        ·
        9 months ago

        Fascinating

        • tate@lemmy.sdf.org
          link
          fedilink
          English
          arrow-up
          8
          ·
          9 months ago

          Chill, Spock.

    • captainlezbian@lemmy.world
      link
      fedilink
      English
      arrow-up
      8
      ·
      9 months 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

    • Björn Tantau@swg-empire.de
      link
      fedilink
      English
      arrow-up
      3
      arrow-down
      1
      ·
      9 months ago

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

      • BB84@mander.xyzOP
        link
        fedilink
        English
        arrow-up
        2
        ·
        9 months 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)

    • Skalix@lemmy.world
      link
      fedilink
      English
      arrow-up
      2
      ·
      9 months 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: https://www.youtube.com/watch?v=ge_j31Yx_yk

    • itslilith@lemmy.blahaj.zone
      link
      fedilink
      English
      arrow-up
      1
      ·
      9 months ago

      deleted by creator

  • TheSlad@sh.itjust.works
    link
    fedilink
    English
    arrow-up
    18
    ·
    9 months ago

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

    • itslilith@lemmy.blahaj.zone
      link
      fedilink
      English
      arrow-up
      23
      ·
      9 months 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

      • BB84@mander.xyzOP
        link
        fedilink
        English
        arrow-up
        4
        ·
        edit-2
        9 months ago

        Kinetic energy or total energy? Assuming the rose weight 10 grams I get that 1.12PJ total energy, but only 0.23PJ is kinetic.

        • itslilith@lemmy.blahaj.zone
          link
          fedilink
          English
          arrow-up
          8
          ·
          9 months ago

          In hindsight I was a bit generous with the weight, I assumed 50g

          • BB84@mander.xyzOP
            link
            fedilink
            English
            arrow-up
            7
            ·
            9 months ago

            chonk rose 😳

            • Fuck spez@sh.itjust.works
              link
              fedilink
              English
              arrow-up
              2
              ·
              9 months ago

              Only 10MT instead of 50 then?

              • BB84@mander.xyzOP
                link
                fedilink
                English
                arrow-up
                2
                ·
                9 months ago

                One ton of TNT is 1E9 calories which is 4 gigajoules. So 0.2 petajoules should be only 50 kilotons of TNT?

                • Fuck spez@sh.itjust.works
                  link
                  fedilink
                  English
                  arrow-up
                  2
                  ·
                  9 months ago

                  A fart in the wind next to the Tsar Bomba. My disappointment is immeasurable and my day is ruined.

    • vrek@programming.dev
      link
      fedilink
      English
      arrow-up
      4
      ·
      edit-2
      9 months 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.

      Edit: just realized I forgot to post the actual link… https://sciencenotes.org/fast-go-make-red-light-look-green-relativistic-doppler-effect/#:~:text=If we take the speed of light to,to convert to km%2Fhr%2C you get 197%2C640%2C000 km%2Fhr.

      • itslilith@lemmy.blahaj.zone
        link
        fedilink
        English
        arrow-up
        4
        ·
        edit-2
        9 months 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 in the photo

        • vrek@programming.dev
          link
          fedilink
          English
          arrow-up
          4
          ·
          9 months ago

          Actually I think that would then add a additional charge for registration fraud

    • FleetingTit@feddit.org
      link
      fedilink
      English
      arrow-up
      3
      ·
      9 months ago

      60% of lightspeed, according to another commenter.

    • tacosanonymous@lemm.ee
      link
      fedilink
      English
      arrow-up
      3
      ·
      edit-2
      9 months ago

      Impossibly fast and it would have to be coming right at us.

  • Sam_Bass@lemmy.world
    link
    fedilink
    English
    arrow-up
    7
    ·
    9 months ago

    Speed chills

    • andrew_bidlaw@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      3
      ·
      edit-2
      9 months 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

    • andrew_bidlaw@sh.itjust.works
      link
      fedilink
      English
      arrow-up
      2
      ·
      edit-2
      9 months ago

      deleted by creator

  • itslilith@lemmy.blahaj.zone
    link
    fedilink
    English
    arrow-up
    3
    ·
    9 months ago

Science Memes@mander.xyz

science_memes@mander.xyz

Subscribe from Remote Instance

Create a post
You are not logged in. However you can subscribe from another Fediverse account, for example Lemmy or Mastodon. To do this, paste the following into the search field of your instance: !science_memes@mander.xyz

Welcome to c/science_memes @ Mander.xyz!

A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.



Rules

  1. Don’t throw mud. Behave like an intellectual and remember the human.
  2. Keep it rooted (on topic).
  3. No spam.
  4. Infographics welcome, get schooled.

This is a science community. We use the Dawkins definition of meme.



Research Committee

  • !spiders@lemmy.world

Other Mander Communities

Science and Research

  • !academia@mander.xyz
  • !science@mander.xyz
  • !scicomm@mander.xyz

Biology and Life Sciences

  • !abiogenesis@mander.xyz
  • !animal-behavior@mander.xyz
  • !anthropology@mander.xyz
  • !arachnology@mander.xyz
  • !balconygardening@slrpnk.net
  • !biodiversity@mander.xyz
  • !biology@mander.xyz
  • !biophysics@mander.xyz
  • !botany@mander.xyz
  • !ecology@mander.xyz
  • !entomology@mander.xyz
  • !fermentation@mander.xyz
  • !herpetology@mander.xyz
  • !houseplants@mander.xyz
  • !medicine@mander.xyz
  • !microscopy@mander.xyz
  • !mycology@mander.xyz
  • !nudibranchs@mander.xyz
  • !nutrition@mander.xyz
  • !palaeoecology@mander.xyz
  • !palaeontology@mander.xyz
  • !photosynthesis@mander.xyz
  • !plantid@mander.xyz
  • !plants@mander.xyz
  • !reptiles and amphibians@mander.xyz

Physical Sciences

  • !astronomy@mander.xyz
  • !chemistry@mander.xyz
  • !earthscience@mander.xyz
  • !geography@mander.xyz
  • !geospatial@mander.xyz
  • !nuclear@mander.xyz
  • !physics@mander.xyz
  • !quantum-computing@mander.xyz
  • !spectroscopy@mander.xyz

Humanities and Social Sciences

  • !archaeology@mander.xyz
  • !folklore@mander.xyz
  • !history@mander.xyz
  • !old_maps@mander.xyz

Practical and Applied Sciences

  • !exercise-and sports-science@mander.xyz
  • !gardening@mander.xyz
  • !self sufficiency@mander.xyz
  • !soilscience@slrpnk.net
  • !terrariums@mander.xyz
  • !timelapse@mander.xyz

Memes

  • !bushrat_confidential@slrpnk.net
  • !science_memes@mander.xyz

Miscellaneous

  • !answered@mander.xyz
  • !mander@mander.xyz
Visibility: Public
globe

This community can be federated to other instances and be posted/commented in by their users.

  • 1.93K users / day
  • 5.78K users / week
  • 11.4K users / month
  • 23.4K users / 6 months
  • 1 local subscriber
  • 14.5K subscribers
  • 4.44K Posts
  • 98.8K Comments
  • Modlog
  • mods:
  • Salamander@mander.xyz
  • fossilesque@mander.xyz
  • SciBot@mander.xyz
  • fossilesque@lemmy.dbzer0.com
  • BE: 0.19.9
  • Modlog
  • Instances
  • Docs
  • Code
  • join-lemmy.org