The developed ferroelectric model however is based upon biologically flawed
assumptions and leads to problematic results. The conformational states that are
considered to represent single bits (qubits) designated with α and β, or up and
down, are indeed boundary conformations that trigger assembly <-> disassembly
of the microtubules, therefore cannot be used for computation by stable
microtubule. That’s why the calculations show effectiveness of the electric field
only when it exceeds 105 V/m in the cytoplasm (biological absurd, the
microtubules decompose at 2x103 V/m as shown by Stracke et al. (2001).
The change in the dipole moment of the tubulin dimer is supposed to be result
from electron hopping between the α- and β-tubulin and is not associated with
mechanical rotation of the dimer. Brown & Tuszynski (2003) investigate the
biological electron conductance of microtubules and the associated electron
hopping when electric field is applied. The energy value for intra-dimer hopping is
estimated to be ~ 0.4eV and for the inter-dimer hopping ~ 1.0eV. The
microtubule is not insulator but its conductivity depends on the lattice geometry
(13B lattice has lower resistance) and the boundary conditions (whether the
microtubule is wrapped up or not). The situation is compared to carbon
nanotubes, where particular sets of boundary conditions produce a
semi-conducting nanotube while the appropriate choice of wrapping the
nanotube gives rise to metallic conduction (Dresselhaus et al., 1996).
The intraneuronal electric field however could not supply the needed energy for
the electron hopping. The work W (respectively the energy needed) for
intra-dimer hopping could be assessed from the formula:
(105) W = F7 ∙ 7 = E ∙ q ∙ 7
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