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Light and Perception

  1. Jan 31, 2005 #1
    Hi everyone, I'm new to this forum.

    I'm not a physicist or a mathematician, but do try to make sense of the way things work.

    My question is - is it safe to generalize that sitting on a park bench, watching your surroundings is like watching a movie who's frame rate is the speed of light?

    If so, is there a mathematical constant that represents the lag time between my environment and my perception of my environment?

    Thanks -
  2. jcsd
  3. Jan 31, 2005 #2
    pls elaborate what you said
    speed of light has unit of distance/time
    frame rate has unit of frames/time
    how can you compare these two?
  4. Jan 31, 2005 #3
    In watching a movie, I am watching pictures go by at 29.9 fps. If I see a person jog by, that image is traveling at the speed of light towards me. That light reaches eyes in wave form. If I slow that process down, I can imagine that the light I see can be cross sectioned into a single 'frame' when time is the smallest measurement larger than infinitely small. OMG!! Am I describing... the MATRIX!! Sorry, just kidding. But really - is there a point at which the time variable can be small enough that a light wave breaks down into sections - or 'frames'?
  5. Feb 1, 2005 #4


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    There are two separate things here that you are confusing to be the same thing.

    The image that you see from a movie IS travelling at the speed of light to reach your eye. There's no difference than seeing an object live. What you are trying to include here is the RATE at which your eye+brain can perceive changes (or the resolution of the rate of change) of motion. There is a lag in how fast this can occur based on the fact that we do not see the frames moving across the projector at so-and-so rate when we watch a movie in a theater. But this says nothing about how fast the signal from the object to our eyes travel. It only says something about the ability of our eyes+brain system to perceive the rate of change.

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