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?
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Comments • 6 263

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    • Doom2exe
      Doom2exe  3 gün önce

      By far one of best channel on TRclips keep up great work guys

      • chandan baidya
        chandan baidya  2 aylar önce

        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  3 aylar önce

          Einen wunderschönen guten Morgen😀☀😅🙃😘

          • yassine achagui
            yassine achagui  23 saatler önce

            Let's all just accept that there is a Creator

            • Pine Tree808
              Pine Tree808  Gün önce

              *Gwyn wants to know your location*

              • DarkVitamins
                DarkVitamins  2 gün önce

                Hey, I'm dumb as fuck. Can someone explain to me why we decided c to be the ultimate speed? If something was approaching faster than light; We wouldn't see it before it hit us. If something was going away from us faster than the speed of light the photons would never reach us. Explain it to me as if I were 5; why do we assume our senses can measure the extreme limits of the universe, instead of the "human brain can only comprehend limits" of the universe?

                • Nasiruddin Sk
                  Nasiruddin Sk  2 gün önce

                  Impressed by the first line💝

                  • I dont wanna use my name
                    I dont wanna use my name  2 gün önce

                    So the sky is blue in the middle of the day because light less light is absorbed due to a shorter distance of atmosphere it has to travel through thus a shorter wavelength and red light is due to a longer distance thus longer wavelengths and space is black because it is a vacuum

                    • cammiecookies
                      cammiecookies  3 gün önce

                      baby don't blind me, no more

                      • Виталий Курилов

                        What is 6 color rainbow?

                        • 0g1f
                          0g1f  4 gün önce

                          What is light? *L I G H T*

                          • Joe Mommah
                            Joe Mommah  4 gün önce

                            'what is light' Baby don't hurt me Don't hurt me Nomo

                            • xp0s
                              xp0s  5 gün önce

                              When the wiggly-wiggly thing has bigger size than your home.

                              • Ultimate Gaming James
                                Ultimate Gaming James  6 gün önce

                                its okay

                                • Glory !!!!!!
                                  Glory !!!!!!  8 gün önce

                                  That video was fast....😵

                                  • Ohh LanLa
                                    Ohh LanLa  8 gün önce

                                    And thought the title said 'What is life' LOL

                                    • uncleshan
                                      uncleshan  8 gün önce

                                      this is intense 🤣

                                      • KaBluey
                                        KaBluey  9 gün önce

                                        whats faster the universe's expansion or the speed of light

                                        • Nestor Enriquez
                                          Nestor Enriquez  10 gün önce

                                          Light can be destroyed? I thought energy is neither created nor destroyed.

                                          • Elaine Paulino Garcia
                                            Elaine Paulino Garcia  10 gün önce

                                            Todas las personas que sepan que son los átomos las moléculas y los neutrones saben que es la luz y eso que tengo 12 años

                                            • as aa
                                              as aa  12 gün önce

                                              I thought we can see 400nm-700nm wave because the main component of black body radiation is on these area.

                                              • Intuser Double
                                                Intuser Double  12 gün önce

                                                Is photon of sunlight has more energy than the photon of artificial light?

                                                • DivinityOfBLaze
                                                  DivinityOfBLaze  13 gün önce

                                                  Baby don't hurt me,

                                                  • Failed Hivemind
                                                    Failed Hivemind  13 gün önce

                                                    What is heavy then?

                                                    • RemoteControlled PotatoChip

                                                      It's the shiny thing that helps you see

                                                      • Teo H
                                                        Teo H  15 gün önce

                                                        How would the world look if we could see lower and higher frequencies? Or is that a fundamentally dumb question?

                                                        • Xenocross Prajnadeva
                                                          Xenocross Prajnadeva  15 gün önce

                                                          Wait, so visible light is another proof of evolution?

                                                          • Alvin Luk
                                                            Alvin Luk  16 gün önce

                                                            Baby don't hurt me

                                                            • Science Revolution
                                                              Science Revolution  17 gün önce

                                                              Light is visible alternating current. Lightwaves must exist within matter. Lightwaves are longitudinal waves. Light is not a photon particle. Light cannot become matter. Light is the universe's free electricity. Sunlight stays in Sun's plasma. Sunlight on earth stays in Sun facing atmosphere. How does sunlight travel through space to reach us? Sunlight stays within the plasma on the Sun; sunlight does not travel in space. Sunlight transfers its energy to earth instantly through an invisible giant rigid rod. One end of the rod sets on the Sun's plasma and covers half of the Sun, while one end sets on earth's atmosphere and covers half of the earth. That rod is made of the repulsion force between the line of sight electrons on the surface of the Sun's plasma and on the surface of the earth's outer atmosphere. That rod of force is, in fact, billions of times stronger than a steel rod; it locks the atoms touched on both ends as one, conducts electrical resonance between the Sun and the earth, and keeps alternating current on the Sun and on earth oscillating at the same frequency. The same rod of repulsion force connected all the stars, moons, planets and every mass in the universe altogether, just like gravity connected them all together. Gravity pulls all matters together, while repulsion force pushes all matter apart. Coulomb discovered repulsion force and attraction forces are like the hands of God. God holds the universe with his left hand and plays a love song with his right hand.

                                                              • Blah blah Blah blah blah blah

                                                                So, if i begin exercising and losing weight, i can travel at the speed of light?

                                                                • Sword Guy
                                                                  Sword Guy  18 gün önce

                                                                  It aint heavy

                                                                  • Avoidmk_c
                                                                    Avoidmk_c  19 gün önce

                                                                    Kurzgesagt: 4:06 Blind people:

                                                                    • Losusix _
                                                                      Losusix _  20 gün önce

                                                                      too fast for me

                                                                      • Google Google
                                                                        Google Google  22 gün önce

                                                                        You are perfect ..Thank you

                                                                        • Mr Unsichtbar
                                                                          Mr Unsichtbar  22 gün önce

                                                                          What is light? Short answer : you die

                                                                          • Darren Ross
                                                                            Darren Ross  24 gün önce

                                                                            Baby dont hurt me Don't hurt me.. No more...

                                                                            • Mebin G Babu
                                                                              Mebin G Babu  24 gün önce

                                                                              What is the speed of light just after passing a viscous medium in space?

                                                                              • Junjun
                                                                                Junjun  24 gün önce

                                                                                Hehe... 5% of known world and 95% of darks, even within the 5%, men dont know why light has no acceleration and said they surely no god. Im not saying there is god, Imsaying within your vaguely 5% knowlegde you surely taking too much assumptions.

                                                                                • Kwinam Martinez
                                                                                  Kwinam Martinez  25 gün önce

                                                                                  1. Get a stick the length of the earth 2. Get on top of the stick 3. Spin stick at 480 rpm. (8 times per second) 4. Since light goes around the diameter of the earth 7.5 times per second, and you're spinning the equivalent of 8x the diameter of the earth per second, you're going faster than light

                                                                                  • eggmar54
                                                                                    eggmar54  25 gün önce

                                                                                    Really enjoyed this simply put , yet informative treatise on light . Thank you ...have subscribed .

                                                                                    • Trek
                                                                                      Trek  25 gün önce

                                                                                      If light is just the way we see around then why don't we see in the dark, i mean why don't we adopt to see frequencies that help us in low lit areas, more then we can already

                                                                                      • GameSeekr041 Contreras
                                                                                        GameSeekr041 Contreras  25 gün önce

                                                                                        Light. Justca prank bro

                                                                                        • Alan S
                                                                                          Alan S  29 gün önce

                                                                                          2164(49), 4/19/2013(1290), 28(5), 2062(2…3), 2061(1…2), 2049(3…4), 5/1/2011, 5(1), 2(28), 15-22, 5841(2080-2081), 532, 2071(4…5), 2097(2…3), 91(1290), 5-2(1290), 72(92), 5/31/2019(12), 7/5/2019(7.1), 3/6/2019-4/20/2019(46), 28(1290), 2/14/2018-3/31/2018(46), 5-2(1), 2063, 4, 928, 2063(3...4). [23(10)22(7-5)8]. [46(20)44(7-14)88]. [61(27)61(7-20)885]. [69(30)66(7-23)888].

                                                                                          • Ajay Anand
                                                                                            Ajay Anand  Aylar önce

                                                                                            What is the mass of photon?

                                                                                            • Michael V
                                                                                              Michael V  23 gün önce

                                                                                              see 3:23

                                                                                              • S A
                                                                                                S A  Aylar önce

                                                                                                Ok but what is a particle?

                                                                                                • Mr.Minzer
                                                                                                  Mr.Minzer  Aylar önce

                                                                                                  Is light made of atoms? I just had a epiphany and need answers.

                                                                                                  • Jason14500 A
                                                                                                    Jason14500 A  Aylar önce

                                                                                                    Have a blessed day!!

                                                                                                    • J E
                                                                                                      J E  Aylar önce


                                                                                                      • earth you are here
                                                                                                        earth you are here  Aylar önce

                                                                                                        Time and its axis day per day beacuse why it POEM and you and me but this is You Dont Have The Cell You are NOT HERE

                                                                                                        • Kiri Beats
                                                                                                          Kiri Beats  Aylar önce

                                                                                                          Make a video on quantum physics

                                                                                                          • medexamtoolsdotcom
                                                                                                            medexamtoolsdotcom  Aylar önce

                                                                                                            Don't tell me no one knows why light's speed is finite. I know why it is. Because of the wave equation. The exact speed of light is a direct consequence of the permittivity (dielectric constant) of free space and permeability (magnetizability) of free space. The wave equation the partial differential equation vxx+vyy+vzz=k*vtt, simply emerges out of Maxwell's equations, and the permittivity and permeability of free space are what determine the constant there.

                                                                                                            • Paul Casabona
                                                                                                              Paul Casabona  Aylar önce

                                                                                                              Did you just make that up!

                                                                                                              • Tobias DPunkt
                                                                                                                Tobias DPunkt  Aylar önce

                                                                                                                sure, it comes out of that equastion, almost all physicists know that. But you don't know WHY that are the exact rules. Why does light behave that way? A formula is always good to know the dependencies, but it doesn't explain why it has them. Unless you really know, then congratz on the nobel prize

                                                                                                                • kirby march barcena
                                                                                                                  kirby march barcena  Aylar önce

                                                                                                                  I saw the light.

                                                                                                                  • Keheck
                                                                                                                    Keheck  Aylar önce

                                                                                                                    Kurzgesagt: "What does make visible light special then? Nothing!" Also Kurzgesagt: "Visible light is the only set of electromagnetic radiation that propagates well in water"

                                                                                                                    • Rob Funkhouser
                                                                                                                      Rob Funkhouser  Aylar önce

                                                                                                                      Light actually doesn't travel the speed of the universe, bc it would then outpace the speed of the universe, which isn't possible. Light is slower than the expansion of the universe, which encompasses everything we know, at least for the moment.

                                                                                                                      • ZACHARY FRENCH
                                                                                                                        ZACHARY FRENCH  Aylar önce

                                                                                                                        "Light also has a wave particle duality. Being kind of a particle and a wave at the same time... although this is a lie." I swear to God Kurzgesagt

                                                                                                                        • Merik Malhads
                                                                                                                          Merik Malhads  Aylar önce

                                                                                                                          Anyone else really bugged about how everyone uses a 150 year old model to represent atoms? Plus the fields that encompass electron orbital shells look way cooler anyway.

                                                                                                                          • Camcolito
                                                                                                                            Camcolito  Aylar önce

                                                                                                                            'We don't have a smart answer here' - That seems to be a routine occurrence in contemporary theoretical physics.

                                                                                                                            • Rick Robitaille
                                                                                                                              Rick Robitaille  Aylar önce

                                                                                                                              What would we see if homosapiens evolved eyes That only detect high energy Photons Are very high energy photons massless?

                                                                                                                              • Rick Robitaille
                                                                                                                                Rick Robitaille  12 gün önce

                                                                                                                                Well still waiting an answer

                                                                                                                                • Rick Robitaille
                                                                                                                                  Rick Robitaille  Aylar önce

                                                                                                                                  Do you think light accelerates when squeezed into a singularity. If gravity can bend it Slow it down to zero in a black hole It must reverse its speed then make it go faster than we think Maybe the the new golden age of black hole research should be reinvigorated to What does a singularity really do

                                                                                                                                  • Rick Robitaille
                                                                                                                                    Rick Robitaille  Aylar önce

                                                                                                                                    What do you think of varying Speed of light Einstein considered its implications before it at the time would have destroyed general relativity?physics Blasphemy or are we missing something. How can we slow light but Apparently even in vacuum But can't speed it up After all its massless

                                                                                                                                    • Rick Robitaille
                                                                                                                                      Rick Robitaille  Aylar önce

                                                                                                                                      Captain Kirk thanks

                                                                                                                                      • Acke Brocke
                                                                                                                                        Acke Brocke  Aylar önce

                                                                                                                                        What would happen if one stood on a train going at the speed of light while throwing a basketball in the same direction?

                                                                                                                                        • OrangeJackson
                                                                                                                                          OrangeJackson  Aylar önce

                                                                                                                                          How does a photon keep propelling itself forward?

                                                                                                                                          • Captain Quirk
                                                                                                                                            Captain Quirk  Aylar önce

                                                                                                                                            It doesn't have to keep propelling itself forward. Anything that moves will continue to keep moving in a straight line until some other force acts on it. Newton's first law of motion. (Of course, that technically only applies to matter, but the analogy holds true for photons, too.)

                                                                                                                                            • Mc Jethro Pov Tee
                                                                                                                                              Mc Jethro Pov Tee  Aylar önce

                                                                                                                                              Boku no Picometer

                                                                                                                                              • riverdung2000
                                                                                                                                                riverdung2000  Aylar önce

                                                                                                                                                When explain what is light, wouldn’t suffice to say ....... we don’t know, rather than a bunch of words that mean nothing?

                                                                                                                                                • Sanchit Priyadarshi
                                                                                                                                                  Sanchit Priyadarshi  Aylar önce

                                                                                                                                                  Kurzgesagt always brings up something great to do with !💞

                                                                                                                                                  • Brian YT
                                                                                                                                                    Brian YT  Aylar önce

                                                                                                                                                    totally bonkers

                                                                                                                                                    • Dawood Haroon
                                                                                                                                                      Dawood Haroon  Aylar önce

                                                                                                                                                      Well I usually understand English but this is some other language.

                                                                                                                                                      • cornishcactus
                                                                                                                                                        cornishcactus  Aylar önce

                                                                                                                                                        Photons experience no time, from it's moment of creation to absorption as far as it is concerned no time has passed. This is why it's speed is exactly C, it can't go faster as it would experience time backwards and it can't go slower because it would experience time forwards. So the question isn't why is the photon going at C, because it has to, the question is why isn't a photon allowed to experience time?

                                                                                                                                                        • siti zu
                                                                                                                                                          siti zu  Aylar önce

                                                                                                                                                          Allahumma Ya Nuur

                                                                                                                                                          • Vance Biondo
                                                                                                                                                            Vance Biondo  Aylar önce

                                                                                                                                                            " CHRIST" 🖐 bye

                                                                                                                                                            • psychonaut ready for launch!

                                                                                                                                                              Im a simple man. I see a nautulus on the thumbnail. I like.

                                                                                                                                                              • Destry Atkinson
                                                                                                                                                                Destry Atkinson  Aylar önce

                                                                                                                                                                Do a video on the bubble multiverse theory or just multiverses

                                                                                                                                                                • Andy Everett
                                                                                                                                                                  Andy Everett  Aylar önce

                                                                                                                                                                  That was a 10, thanks for that.

                                                                                                                                                                  • Domin Go
                                                                                                                                                                    Domin Go  Aylar önce

                                                                                                                                                                    baby don't hurt me

                                                                                                                                                                    • I Like YouTube.
                                                                                                                                                                      I Like YouTube.  Aylar önce

                                                                                                                                                                      Light is pointless but its something that helps us with the internet so I could not be more grateful tho lol.

                                                                                                                                                                      • Zeyrakıl 1935
                                                                                                                                                                        Zeyrakıl 1935  Aylar önce

                                                                                                                                                                        Türk var mı

                                                                                                                                                                        • AndyPutt1
                                                                                                                                                                          AndyPutt1  Aylar önce

                                                                                                                                                                          In other words- we don't know. In fact we still have basically no idea what light is.

                                                                                                                                                                          • Lünkel
                                                                                                                                                                            Lünkel  Aylar önce

                                                                                                                                                                            No, not really.

                                                                                                                                                                            • Sissi Schytte
                                                                                                                                                                              Sissi Schytte  Aylar önce

                                                                                                                                                                              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  Aylar önce

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