I just heard of a protein (acethylcholinesterase) that has a clear electric dipole moment, at least way bigger than most of the known proteins.
Now I wonder if a magnetic field (even as weak as Earth's one) can possibly "influence" such protein, and in what way... Of course I'm trying to figure out a link between "biological matter" and animal "magneto-sensing" and it is not a hypothesis I have read before.
Has anyone worked on that or is interested in, theoretically or experimentally?
Many thanks,
Guillaume
Hi Guillaume,
In principle (according to classical electrodynamics) an electric dipole is not influenced (rotated, translated) by a magnetic field. If magnetic field is caused by current(s) caused by a nearby electric field, then this electric field might affect the electric dipole.
Animal magnetic sensing (homing pigeons, whales, ... are suspected of it) is - as far as I know - still not positively established, let alone explained. A possible speculative explanation might be that these animals possess organo-metallic (o-m) molecules (proteins?) that exhibit molecular magnetism (google/look them up). Analogous to the molecules in the retina that are excited (check in nuclear physics what this means) into a higher energy level by electromagnetic quanta (photons) and can in ways not fully understood signal these excitation events to the brain, so single o-m molecules might be able to signal to the brain the effect of an external magnetic field. Research is needed to show it works along these lines.
Molecular magnetism is a recently started science concerned with the magnetic properties of some organic molecules.
I guess it wil take another century or more to unravel these effects and mechanisms. It is a long chain of events from arriving photons that excite molecules in the retina , then signal via synaptic transmission in nerve fibers to assemble a picture that the brain can tell the body to act on. Analogously, from o-m molecules getting 'excited' by a magnetic field, via synaptic transmission in nerve fibers to form a spatial orientation that the brian can tell the body to act on.
So, not molecules with an electric dipole but, in my speculation, o-m molecules that exhibit molecular magnetism, can interact with a magnetic field, and deliver a sense impression or perception.
Not sure if your question was aimed in the direction I took it.
I did not work in this field at all, which is why I call my story a speculation or hypothesis. I am a nuclear/solid state (now called 'condensed matter') physicist and understand the presently accepted quantum mechanical concepts to do with molecular structures and vibrations, excited states, general electrodynamics and magnetism and some more. This animal magnetic sensing field should be mined by a bio-physicist who includes nuclear and condensed matter and liquid physics in his toolbox .
Greetings, Geert
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Dear Geert,
Thanks for your answer.
I see. Yes, you have an hypothesis here, not really discussed elsewhere too. Usually people work to validate the presence of magnetite crystals as observed in magnetotactic bacteria and/or establish the function of cryptochrome proteins (a MF sensitive radical pair is created upon photo-excitation of the protein).
Actually I am not 100% convinced -as a biologist- by these hypothesis in animal magnetosensing. BTW, pretty strong evidences of MF sensing are now published for few birds. But I lack for sure the "physic" background needed to come up with a robust alternative. That is why I asked it in first place. In that, any input by physicists is appreciable :)
Thanks again!
Best wishes,
Guillaume