A.2 Sensitivity coefficients
The text introduces several sensitivity coefficients. We recall their definition here.
- Given an observable , the value of which depends on a set of primary parameters , the
sensitivity of the measured value of to these parameters is
The value of the quantities requires a physical description of the system.
- the parameters can be related to a set of fundamental constant and we define
The computation of the coefficients requires one to specify the theoretical framework and
depends heavily on our knowledge of nuclear physics and the assumptions on unification.
- A particular sets of parameters has been singled out for the sensitivity of the mass of a body
to a variation of the fundamental constants
One also introduces
- In models where the variation of the fundamental constants are induced by the variation of a scalar
field with define
- In class of models the variation of the constants can be related to the gravitational potential by