Time Stops at the Speed of Light. What Does that Mean?

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Published 2024-04-21
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You might have heard that according to Einstein's theories of special and general relativity time doesn't pass for light, or that time actually stops for light. Can this possibly be correct? In this video, I will look at what the maths says and discuss what it means.

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#science #physics

All Comments (21)
  • Light: "I'd like to respond to your question, but I simply don't have the time!"
  • @0cellusDS
    A photon checks into a hotel and is asked if it needs help with its luggage. It responds: "No thanks, I am travelling light.".
  • Time slows down when at work and speeds up when you are not!!!! Time also speeds up after 50 years of age!!!!!!
  • @phuzed37
    "I have always been everywhere I am." - Light
  • @hexagram531
    She had me within a minute, with "and who is not looking for a way to get off the planet at this point..."
  • @dadamson
    I would love to see a follow-up video to explain how photons can have a frequency (cycles/T) given that T = 0 from the perspective of the photon.
  • @Matelight_IT
    "last time I checked YouTube didn't support 4-dimentional graphic" - this is gold
  • @roger7341
    Speaking of Time stopping for a Light, I once travelled with my boss to a small town in northern Michigan, which had only a single stoplight at the corner of Walk and Don't Walk. He was driving the rental car to the only restaurant in town and accidentally ran through the only red light in town and was immediately pulled over by the only Sheriff in town and handed a ticket.
  • I love Sabine. She is the irrefutable manifestation of the differences between levels of intelligence. I click on her presentations several times a month, intrigued by the possibility that I might actually understand one of them from beginning to end... against the accumulating evidence of my experience. I follow her as far as I can, then come to the separation point where, like a rocket's booster dropping off to oblivion as the rocket soars toward space, I disengage and fall back to my accustomed level. Nevertheless, I love the ride, however brief, and return for more, grateful and perhaps a micro measure more enlightened than before. Danke, Sabine!
  • @t2k777
    I feel dumber having watched this
  • @Vondoodle
    Proper time - like tea and cake time
  • @mrstevecox7
    I think that the confusion for many of us non-physicists about timeless light arises from the common application of time based parameters to that light. Take Blue light for example: Say it has a frequency of 600 x 10^9 Hz, or (times per second). If a photon of that light travels for a light year in distance for a 'stationary observer' at it's destination. How many "times" has that light 'pulsed'/ vibrated in its travel? From the observer POV, it has vibrated maybe 1.9X10^22 times over the year. But if time has stopped for the light, then it's time clock cannot allow even one pulsation during the journey. How then can the concept of 'frequency' be applied to a photon of any em radiation? Or is this another of those things like "spin" for an electron (which is not "actually" spinning..)?
  • For simpletons like me it would help if the graph was setup in such a way that the words "shorter" and "longer" would correspond to shorter and longer lines on the actual drawing.
  • @wootcrisp
    I don't think I've ever heard this particular relationship between light and time worded so well. Thank you.
  • @Mortac
    Hi. Light here. I can tell you that the future is bright.