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Faster than the Planck second

  1. Oct 27, 2012 #1
    Today I was driving down the road, on the side of the road, there was a fence made of many vertical slats.

    I noticed that that sun was blinking on and off like a strobe light, as each individual slat would shield the sun, and each space in between the slats would expose it. I thought, if my car remained moving at the same speed, but my parallel distance between the fence was increased, the sun would flicker at an even faster speed.

    In fact, if I were to increase my distance enough, and also increase my velocity, and decrease the distance between each slat, the time between each flicker would be less than a planck second.

    Am I missing something?
  2. jcsd
  3. Oct 27, 2012 #2


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    What is a "Planck second"?
  4. Oct 27, 2012 #3
    The time is takes light to travel one Planck Length.
  5. Oct 27, 2012 #4
    I think that's actually called the "Planck time".
  6. Oct 27, 2012 #5
    I would think the distance would either have to drop below the Planck length or your vehicle would have to travel faster than c (a ridiculous violation of SR) for that to occur, and most modern theories don't even posit lengths 'shorter' than the Planck length to have any meaning. Certainly not in the ever-popular string/M-theory, in which the intrinsic string length L[itex]_{s}[/itex], which is on the order of the Planck length, is considered to be the fundamental length.
    Last edited: Oct 27, 2012
  7. Oct 27, 2012 #6

    Vanadium 50

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    What is a "Planck second", how does it differ from a regular second, and what makes you think it (or anything) is a minimum unit of time?
  8. Oct 28, 2012 #7
    Well, when I did the math, I realized it doesn't provide any practical way of getting a strobe frequency under the femtosecond.

    It did get me to think about a way to time attoseconds though.

    Imagine we had a thin cylindrical disc, centered about a laser. The sides of the disc is divided into 1 trillion parts, such that the laser can pass through each of the 1 trillion openings on the side of the disc.

    We spin this disc 1,000 times per second, giving us 1 quadrillion hertz. Now, we take each individual pulse that exits the disc and we must find a way to divide it 1,000 times.

    Perhaps you could let the laser pass through a very narrow fiber optic-like tunnel, with 1,000 appropriately spaced mini lasers that emit a laser perpendicular to the path of the laser, such that a capacitor would discharge for each of the 1,000 cells when the laser inference hit a critical value.
  9. Oct 29, 2012 #8


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    Is there a point to this thread other than a mindless rambling?

  10. Oct 29, 2012 #9
    it would give you some crazy diffraction patterns...like a disco ball.
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