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thanks

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- Thread starter Mephisto
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- #1

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thanks

- #2

nicksauce

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From wikipedia:

"The following thought experiment illuminates this fact. The task is to measure an object's position by bouncing electromagnetic radiation, namely photons, off it. The shorter the wavelength of the photons, and hence the higher their energy, the more accurate the measurement. If the photons are sufficiently energetic to make possible a measurement more precise than a Planck length, their collision with the object would, in principle, create a minuscule black hole. This black hole would "swallow" the photon and thereby make it impossible to obtain a measurement. A simple calculation using dimensional analysis suggests that this problem arises if we attempt to measure an object's position with a precision to within a Planck length."

The Planck time is the time it takes for a particle traveling at c to cross the Planck length.

Also, dimensional analysis shows that the Planck length is the only length that can be obtained from some mix of the 3 important physical constants G, h, c (up to a scale factor), so this shows that it might (must?) have some physical importance. If space and time are discrete it would seem that the Planck length and time would be the natural units for discreteness.

"The following thought experiment illuminates this fact. The task is to measure an object's position by bouncing electromagnetic radiation, namely photons, off it. The shorter the wavelength of the photons, and hence the higher their energy, the more accurate the measurement. If the photons are sufficiently energetic to make possible a measurement more precise than a Planck length, their collision with the object would, in principle, create a minuscule black hole. This black hole would "swallow" the photon and thereby make it impossible to obtain a measurement. A simple calculation using dimensional analysis suggests that this problem arises if we attempt to measure an object's position with a precision to within a Planck length."

The Planck time is the time it takes for a particle traveling at c to cross the Planck length.

Also, dimensional analysis shows that the Planck length is the only length that can be obtained from some mix of the 3 important physical constants G, h, c (up to a scale factor), so this shows that it might (must?) have some physical importance. If space and time are discrete it would seem that the Planck length and time would be the natural units for discreteness.

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- #3

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The "Planck time" is just a convenient unit of time for some applications.

thanks

It is not a "smallest unit of time" and there is no reason that shorter time intervals

don't exist.

- #4

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like from t=0s to t=1^-43s physics breaksdown and doesnt describe this period

is this all wrong in which case ive plucked from absolute nothing??

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