The idea is predicated on the supposition that particle mass, in this case of the electron, is maintained and mediated by a classical background EM field (CBF). That is, the mass would be zero if the fields were absent. The direct-action theory points in this direction, but is still immature. Therefore, at this stage some of the predictions necessary to perform an experiment are no more than guesses. It is not known if the relevant part of the CBF field is quasi-monochromatic at the electron Compton frequency. It may for example be that the field energy density matches that of the Dirac electron-hole ‘sea’ without requiring that it be monochromatic. A finite (renormalized) ZPF is not out of the question either.
The proposal here is to modulate the electron mass electromagnetically – thereby demonstrating the
electromagnetic fungibility of mass. The input is that mass is maintained by a CBF, but without having to
commit to a particular spectrum. More specifically, under the hypothesis that mass is
electromagnetically maintained, dynamic changes in
the effective mass imply corresponding dynamic changes in the CBF, which could, in
principle, be detected as a propagating signal – in practice as a depletion or excess of the steady-state CBF
required to maintain mass elsewhere.
One possibility is to make use of mass modulation (effective mass) as it already occurs for example in a semiconductor lattice, and modulate that through some exterior (eg magnetic) field. Let us call the apparatus in which the effective mass is being modulated as the generator (rather than transmitter), call the outgoing depletion or excess of the alleged background field the signal, and call the test apparatus designed to pick up the signal via sympathetic modulation of the electron masses therein the detector.
The above arguments suggest that we require the generator and detector have overlapping characteristics.
Ideally therefore, they should be the same material. In the generator, modulate the (effective) electron
mass, and look for sympathetic fluctuations of effective electron mass in a detector – light speed delayed.
We need to look for is a material with means of modulating effective mass of electrons by a large amount.
Once we have that, the appropriate means of detection will probably suggest itself.
I prefer modulating the effective mass m* by mechanical means since it
protects against the possibility that the energy for the change is acquired not
from a background EM field but from the modulation source itself. You will see
from the paper by Lange et al that we need to be able to modulate by around 23
thousand atmospheres in order to see a 1% change in effective mass in GaAs.
Bearing in mind we will want to modulate the pressure (under computer control)
piezo seems a good method. I am hoping these pressures can be achieved with a
piezo transducer with a little geometric focusing, whereby the force from the
piezo is delivered to the GaAs by a tapered truncated cone.
More here on piezo pressure transducers::
http://www.physikinstrumente.com/en/products/prdetail.php?sortnr=400600.40
The material may be important: it seems at first reading of the Lange paper
that the sensitivity of m* to pressure in GaAs is a consequence of a strong
non-quadratic term in energy versus momentum in this particular semiconductor.
The Lange method employed some S. de Hass technique (don't know what it is)
to measure m*. Important for us is that the measurement involves a rate of
change with temperature, which is incompatible with our requirements that
modulation and measurement proceed dynamically at some reasonable clip. I
suggest therefore we consider cyclotron resonance instead. A description of
Cyclotron Resonance (CR) as a method of measuring m* in semiconductors is given
in the book by Ashcroft & Mermin 'Solid State Physics', chapter 28 (page 570
in my copy). Dresselhaus has described the CR technique applied to Si and Ge.
Liquid He temperatures were used in the Lange experiment. This is for whatever reason associated with the S. de Hass technique.
Cyclotron Resonance measurement of m* requires that the cyclotron frequency
is much greater than the collision frequency which is a strong function of
temperature. In the Ashcroft & Mermin data the CR at 24GHz was measured at
T=4K, so it looks as if low temperatures will also be required if we adopt this
method. (The DC magnetic fields were of the order of kGauss.) Perhaps a way
forward is an initial investigative phase wherein we find out the precision with
which one can identify a 'collective' m* at various temperatures, starting at
293K and going down from there, to 77K, but to 4K only if necessary.
This is angle dependent. At this stage, and very speculatively, I think we will be able to use the classical Thomson value for the scattering cross-section of the signal. This is σ ~ re2 where re is the classical electron radius ~ 3 x 10-15 m so σ ~ 10-29 . Hence the extinction coefficient k (exponential loss per unit radial length away from generator) will be of order σ times the density of free electrons participating in the measurement. For solid volume number density (of protons and electrons) rho, one has
k = f rho σ
where f is the fraction of electrons available for participation in the measurement (nominally the conduction band occupancy). Typical solid volume density is rho ~ 1023 / m3 . Then