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I was reading an article online pertaining to quantum mechanics and I stumbled across these few sentences.

A look at the corresponding energy regimes shows (Beck and Eccles 1992) that quantum processes are distinguishable from thermal processes for energies higher than $10^{-2}$ eV (at room temperature). Assuming a typical length scale for biological microsites of the order of several nanometers, an effective mass below 10 electron masses is sufficient to ensure that quantum processes prevail over thermal processes.

I would like to know what they mean when they say "is sufficient to ensure that quantum processes prevail over thermal processes". Or possibly just what the difference is between a quantum process and a thermal process.

Original Text (Section 4.4 Beck and Eccles: Quantum Mechanics at the Synaptic Cleft) http://plato.stanford.edu/entries/qt-consciousness/#4

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The quantum uncertainty in position of particles (micro sites) of mass $m$ moving or vibrating at thermal speeds characteristic for a temperature $T$, is given by the thermal De Broglie wavelength $\sqrt{\frac{2 \pi \hbar^2}{m \ kT}}$. If this uncertainty in particle (micro site) position is larger than or comparable to its size, the inter-particle (inter site) interactions must be described quantum mechanically.

For the example quoted, $m$ is 10 electron masses and $T$ is 300 K (room temperature), it follows that the De Broglie wavelength is a few nanometer. Hence, micro sites weighing 10 electron masses can be treated classically (using Newton's laws rather than quantum mechanics) provided they are significantly larger than a few nanometers. If these micro sites are of size a few nanometer (or smaller) quantum uncertainty kicks in an the full quantum physics machinery needs to be brought in.

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