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Can we use entropy change value to define the (perhaps fractional) number of bits of information that are lost by and, or, xor gates?

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"these entropy changes" What entropy changes are you referring to? My guess is you're referring to adiabatic, isothermal etc. I don't see why energy entropy should be related to computing entropy so directly. Also, you might be interested in – raindrop Feb 25 '13 at 20:40
I am sorry for that error – abcdefg Feb 25 '13 at 20:45
Possible duplicate: v1 of this Phys.SE post. – Qmechanic Feb 25 '13 at 20:48
I have simple logic gates(and, or, xor). I want to calculate the entropy change due to this gates. Say "or" gate. we have 2 inputs(2 bits 0 or 1) and 1 output. This gate is not reversible, if we know the output, we cannot guess the input bits. We have computed entropy somehow, how to find the number of lost bits – abcdefg Feb 25 '13 at 20:49
@Raindrop Surprisingly, the information and thermodynamic entropies associated with the erasure of the bit are deeply related: see Bennett's seminal work, the Thermodynamics of Computation. – Mark Mitchison Feb 25 '13 at 21:45

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