[derek w]

do not know if my understanding is correct?If Pl=plank length.
Then pl^3 x c=smallest amount of energy possible?

[imatfaal]

From my basis knowledge the planck energy would be the energy equivalent of the planck mass (which is actually fairly big at 2.17x10-8 kg - an eyelash is about the same order of magnitude) and similarly from the energy time uncertainty principle it is hbar divided by the planck time. Your dimensions would not fit - energy does not equal distance cubed times velocity- the exact definition is here

The planck scale is not entirely a boundary beyond which you cannot go - there are myriad examples of things smaller than the planck mass - it is scale of energies(very high), lengths(very small), times (very short) etc at which quantum field theory encounters problems due to the effects of gravity. The energies required to experiment at the planck scale are way beyond those we can create artificially. We can look at the fossil cosmology from the period after the big bang and use these remnants to try and understand what happened and more about sub-planck scale physics

[derek w]

Sorry I not being clear.I was thinking of Pl^3 as a volume of stuff,unknown stuff.

so my Pl^3 volume of unknown stuff travelling at the speed of light = kinetic energy.

If my volume of unknown stuff is spinning,and each spin produces h amount of energy.

then I can say E=f x h.

My question would be is the plank length anything to do with the energy of a photon?

[imatfaal]

derek w, on 10 March 2012 - 02:46 PM, said:

Sorry I not being clear.I was thinking of Pl^3 as a volume of stuff,unknown stuff.

so my Pl^3 volume of unknown stuff travelling at the speed of light = kinetic energy.

"Stuff" does not go at the speed of light - only massless particles go that fast

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If my volume of unknown stuff is spinning,and each spin produces h amount of energy.

then I can say E=f x h.

Energy = Reduced Planck's Constant (h bar) times frequency: this is the energy of a photon - not to the best of my knowledge a spinning massive object. I would have assumed any massive object would have the mass as part of the equation - ie same/similar to the classical formula - Rotational Energy = 1/2 Moment of Inertia times the angular speed squared

Quote

My question would be is the plank length anything to do with the energy of a photon?

the planck length is just a term of measurement. I really would recommend re-reading the first few pages of this thread and then reading wikipedia on planck units.