The extrinsic method
A mathematical method for physical applications
© Thierry PERIAT : Texts, photos, and ideas
The extrinsic method
is a mathematical
method. It is a helpful tool to get answers to the socalled (E) question. The
(E) question is: “Consider a deformed tensor product (DTP) in E(D, K) where
usually K represents either R or C. Consider the image of that DTP in the dual E*(D,
K) of E(D, K). How can I divide it and get a pair ([P], z) in M(D, K) x E(D, K)?”
Please
discover the basics and the method on the page “Mathematical
methods”.
Applications (personal propositions)
In
physics, I have applied this method in two domains:

The
geodesic deviation equation for weak gravitational fields; (text coming soon
again here).

The
Heisenberg’s uncertainty principle; on this website: “A. Einstein versus W. Heisenberg” and on the www.researchgate.net
website.
Applications (in the literature)
In the
community, I newly discovered an article (under the Common Creative licence) titled:

“Quantum effective action for
degenerate vector field theory“ published on the 17^{th} October 2018 by
the American Physical Society in Phys. Rev. D 98, 085014 (2018)” in which the
formula (5) has exactly the formalism induced by the analysis of the Lorentz
force density (alias LorentzEinstein force in my semantic) with the extrinsic
method when the geometry is invariant (see more details in my document ISBN…
0311 directly on the www.researchgate.net website).
F =  G^{1}.
H
Where G represents the local nondegenerated
fourdimensional metric and H a quasiclassical Hessian of which the interpretation
is related to an EM potential.
Provisory conclusion
My hope
is to have been able to convince the readers that that method can have some
advantages in physics.
© Thierry PERIAT, 23 November 2018.