What Is Light?

  • Published: 15 October 2015
  • We are so used to some things that we stopped wondering about them. Like light. What is light? Some kind of wavy thing, right? Kind of.

    Short bonus video for the people waiting for new stuff.

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    What is light?

    Help us caption & translate this video!


Comments • 6 158

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    • chandan baidya
      chandan baidya  1 weeks back

      Do light loose it's speed at any point of time
      Actually after watching videos have a idea about space travel we can definitely move faster than light need your expert advice and guide
      Waiting for response

    • Maxi Immortality
      Maxi Immortality  2 months back

      Einen wunderschönen guten Morgen😀☀😅🙃😘

    • Jackgame
      Jackgame  3 months back

      Wo finde ich die Quellen? (THIS POST IS IN GERMAN)

  • Sissi Schytte
    Sissi Schytte  14 hours back

    Who is here because they have a test the next day and need to squeeze as much information as possible before the test because you didn’t practice at all 😂

    • tsartomato
      tsartomato  18 hours back

      Baby don't hurt me, don't hurt me, no more.

      • Muhammad Yaseen
        Muhammad Yaseen  1 days back


        • jace northern
          jace northern  1 days back


          • Moussa Kamal
            Moussa Kamal  3 days back

            i mostly noticed the word "evolved" which means that there is no creator for the eye and it "evolved" but why an eye "evolved" through time and the cell phone you are holding which is also made from earthy materials didnt "evolve" on its own?

            • Bobby Digital
              Bobby Digital  4 days back

              Nice video, would of been better without the evolution theory.

              • Kob_iss
                Kob_iss  4 days back

                Are just build this way... Tht the real question...

                • Ramzan Hossain
                  Ramzan Hossain  5 days back

                  Indeed, light is great gift of Allah, almighty.

                  • erictko85
                    erictko85  5 days back

                    Do one about sunburns please.

                    • Kitten Defence
                      Kitten Defence  1 weeks back

                      used this to win an arguement

                      • fadhy faizhhh
                        fadhy faizhhh  1 weeks back

                        “So what is so special about visible light”


                        • Miguel Moran
                          Miguel Moran  1 weeks back

                          If the speed of light was infinite,time would start and end at the same time or in an instant

                          • Miguel Moran
                            Miguel Moran  1 weeks back

                            The speed of light if finite so there for there can be space and time, or an existence so to speak

                            • MehBestLamp33
                              MehBestLamp33  1 weeks back

                              Short answer

                              • Pewdiepie Is god
                                Pewdiepie Is god  2 weeks back

                                Why is there a cephalopod in the thumbnail

                                • Kevin Burress
                                  Kevin Burress  2 weeks back

                                  evolution is only a theory and it's not a law of what happened, it's not something that is repeatable for humans and so it's not provable. intelligent design, eugenics is provable and could be law and it's repeatable.

                                  • JR Hermosura
                                    JR Hermosura  2 weeks back

                                    It's just so awesome to think that we are able to study something intangible at a microscopic level.

                                    • Fred Crinson
                                      Fred Crinson  2 weeks back

                                      I'm left confused with further questions. Great video KGS :)

                                      • Julian Ospina
                                        Julian Ospina  2 weeks back

                                        W hat software was used for this? Adobe After Effects or Animate?

                                        • abhi r
                                          abhi r  2 weeks back

                                          Not a very informative video for 2010s ... other knowledge and science channels have set the bar pretty high

                                          • Sunny shah
                                            Sunny shah  2 weeks back

                                            Here is a fun fact.
                                            We need light to see objects. We need objects to know that light exists, because if there were no objects, we would never know if there is light or not.

                                            • Isaa Khan
                                              Isaa Khan  2 weeks back

                                              how about projections

                                              • Frank Xu
                                                Frank Xu  2 weeks back

                                                Light is collection of photons. photon is two massless electric charges( one positive and one negative and the sum is zero)entangled together. the electric charges rotating to contribute the spin for the photon and make photon spin equal to 1. one of the charge rotate right hand and another one rotate left hand. The rotation of these massless charges form an ossilating dipole moment and with the photon move at speed of light ,the photon acting just as the electromagnetic wave.

                                                • Luke Toepfer
                                                  Luke Toepfer  2 weeks back

                                                  Light is light

                                                  • iron gosse
                                                    iron gosse  2 weeks back

                                                    Watching this for my light and optics exam

                                                    • khentherobrine DACULAN
                                                      khentherobrine DACULAN  2 weeks back

                                                      The true question is

                                                      Why is light

                                                      • Jovanni Alvarez
                                                        Jovanni Alvarez  2 weeks back

                                                        I've made a huge discovery concerning light I've called my theory the 3 circle theory created and invented by Jovanni A. 12 stands for God's Government.
                                                        Time is made up of 12 hours dividing day and night. There are also 12 months in a year. There are 12 pitches circle of 5ths and 4ths sound and circle of colors light which is made up of 12 colors. Now 7 represents perfection there are 7 days in a week (time) there are 7 notes in a scale and 7 colors in rainbow. Next is 3 Trinity. What three things make time? future,past, and present
                                                        What 3 things make up color the primary colors red,blue, and yellow and last but not least music or frequencies is made up harmony melody, and rhythm. Now if you zoom back God is the alpha and omega time. Jesus is the light of the world and a rainbow is a sign from God that he will never again punish the world using water. This is a sign of forgiveness. And last but not least, the Holy Spirit frequencies. In the book of 1 Samuel 16:23 David would play the harp to relax King Saul from his evil spirits.

                                                        • Virtue美德
                                                          Virtue美德  2 weeks back

                                                          Okay, if I were to put all these into point form, what would it be like? Can someone help me?

                                                          • Hassan Raza
                                                            Hassan Raza  2 weeks back

                                                            Light is energy like Our soul spirit . Energy

                                                            • manjeet singh
                                                              manjeet singh  2 weeks back

                                                              There is nothing like soul. Thts udeology of idiots

                                                          • madinina97218
                                                            madinina97218  3 weeks back

                                                            Why the title is in French ?

                                                            • ZinZorius 312
                                                              ZinZorius 312  2 weeks back

                                                              When someone translates the title everyone with that language will get the title in their language.

                                                          • madinina97218
                                                            madinina97218  3 weeks back

                                                            Why the title is in French ?

                                                            • Steve Tate
                                                              Steve Tate  3 weeks back

                                                              Light is light end of discussion

                                                              • Godzilla John
                                                                Godzilla John  3 weeks back

                                                                Light was created by God(Father, Jesus, Holy Spirit) according to the bible.

                                                                • Mini J
                                                                  Mini J  3 weeks back

                                                                  Make a video about the twin paradox🐣

                                                                  • wulphstein
                                                                    wulphstein  3 weeks back

                                                                    We need to talk about centrifuging photons.

                                                                    • Xx_p0w3r9g3_xX
                                                                      Xx_p0w3r9g3_xX  3 weeks back

                                                                      2:56 my childhood

                                                                      • JoshAndWhatNot
                                                                        JoshAndWhatNot  3 weeks back

                                                                        This video: what is light
                                                                        Me: light is light

                                                                        • jeff namw
                                                                          jeff namw  3 weeks back

                                                                          Do light have atoms?

                                                                          • jeff namw
                                                                            jeff namw  2 weeks back

                                                                            @ZinZorius 312 what are those? and can we see light it as a small particle

                                                                          • ZinZorius 312
                                                                            ZinZorius 312  2 weeks back

                                                                            @jeff namw Light is composed of photons

                                                                          • jeff namw
                                                                            jeff namw  2 weeks back

                                                                            @ZinZorius 312 how about molecules.

                                                                          • ZinZorius 312
                                                                            ZinZorius 312  2 weeks back

                                                                            No, light doesn't have mass.

                                                                        • Finn Read
                                                                          Finn Read  3 weeks back

                                                                          tank u

                                                                          • momen mostfa
                                                                            momen mostfa  3 weeks back

                                                                            good job guys , i hope you will never stop providing these interesting topics in this very exciting videos
                                                                            it's really so easy to understand these things with this way of presentation with animation way
                                                                            keep going

                                                                            • Light
                                                                              Light  3 weeks back

                                                                              I thank you, kurzgesagt aka Philipp Dettmer and the team, for explaining me in this broad manner. Keep up the good work ^_^

                                                                              • Nyx
                                                                                Nyx  3 weeks back

                                                                                What is light?
                                                                                *Black hole don't hurt me, don't hurt me, no more, no more.*

                                                                                • Juan Ferrer
                                                                                  Juan Ferrer  3 weeks back

                                                                                  Our ancient ancestors were very good at mating and reproducing in a sub-aquatic environment. You could say they were lady-krillers

                                                                                  • Antonio Noack
                                                                                    Antonio Noack  4 weeks back

                                                                                    I think the electric and magnetic field at 2:55 need to be offset by pi/2!

                                                                                    • Brandon Greenland - Glenforest SS (2172)


                                                                                      We must enter...

                                                                                      *... NAUTILUS SPEED!*

                                                                                      • WEEP Q1
                                                                                        WEEP Q1  4 weeks back

                                                                                        What if our wifi use light
                                                                                        "No delay

                                                                                        • Sergio Fierros
                                                                                          Sergio Fierros  4 weeks back

                                                                                          Light is a form of energy, you can not create or destroy energy just change it.

                                                                                          • Sergio Fierros
                                                                                            Sergio Fierros  3 weeks back

                                                                                            @ofek10 no you're so wrong stop being ignorant.

                                                                                          • ofek10
                                                                                            ofek10  3 weeks back

                                                                                            @Sergio Fierros single particles don't experience heat. when an electron and a positron collide they disappear from existence, only leaving gamma photons.
                                                                                            And what do you mean a work form of energy? A photon is just a term used to say "an hf amount of energy in an electromagnetic wave" (when h = plank's constant and f = the frequency of the wave, so when that amount of energy is no longer in an electromagnetic wave, the photon is destroyed.

                                                                                          • Sergio Fierros
                                                                                            Sergio Fierros  3 weeks back

                                                                                            @ofek10 and no when particles collide they release energy in heat form a lot of heat

                                                                                          • Sergio Fierros
                                                                                            Sergio Fierros  3 weeks back

                                                                                            @ofek10 but that's the thing a photon is just a work for a form of energy

                                                                                          • ofek10
                                                                                            ofek10  3 weeks back

                                                                                            @Sergio Fierros first of all matter can be destroyed, i.e. when an electron collides with a positron they both annihilate. Second, Energy isn't destroyed, but a photon by definition is some energy stored in LIGHT, meaning that when that energy is transferred to an electron, there is no energy stored in the light, meaning no photons (by definition) so the photon was destroyed. (but the energy wasn't, just transferred to another thing).