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Comment
. 2016 Sep 8:5:e19569.
doi: 10.7554/eLife.19569.

Problems on the back of an envelope

Polina Anikeeva  1 , Alan Jasanoff  2
Affiliations
Comment

Problems on the back of an envelope

Polina Anikeeva et al. Elife. .

Abstract

Claims that magnetic fields can be used to manipulate biological systems contradict some basic laws of physics.

Keywords: biophysics; magnetic control; magnetogenetics; magnetoreception; neuroscience; none; physical plausibility; structural biology.

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Conflict of interest statement

The authors declare that no competing interests exist.

Figures

Figure 1.
Figure 1.. Molecular-scale magnetic interaction energies.
The energies associated with various magnetogenetic components, as estimated optimistically by Meister, are labeled in magenta. Each is orders of magnitude smaller than the thermal energy per degree of freedom at room temperature (dark blue). In contrast, based on our calculations, interactions involving magnetite particles (Fe3O4; light blue) can exceed the thermal energy (kT) at room temperature. These calculations assume that the magnetization of magnetite is 480 emu/cm3 and that the specific loss power for an individual particle is 24 fW. Note that the x-axis is logarithmic. The strength of the earth's magnetic field varies between about 25 and 65 microtesla at the earth's surface. mT: millitesla; B: magnetic field; k: Boltzmann’s constant; T: temperature.
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Comment on

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