emh or

emh or

On the unit of mass:The mass of a macroscopic object is the sum of that of all its microscopic constituents and

of a weak approximately calculable interaction term.

This hypothesis is implicit in both possible new definitions of the unit of mass.

The concept of mass must be identical at all scales.

At the atomic scale, mass is directly associated with a frequency via Planck constant.

This frequency can be measured directly for atoms and molecules

even though it is quite a large frequency. Measurements of mc2/h are presently performed with a relative uncertainty much better than 10-8.

By additivity the link between a macroscopic mass and a frequency is thus unavoidable.

If one accepts to redefine the unit of mass from that of a microscopic particle such as the electron,

then the link with the unit of time is ipso facto established with a relative uncertainty much better

than 10-8. Both units are de facto linked by the Planck constant to better than 10-8. It seems difficult to ignore this link

and not to inscribe it in the formulation of the system of units, especially since it leads to

a reduction of the number of independent units.

eor0

On electrical units:In the present SI, the values of μ0 and ε0 are fixed and

thus the propagation properties of the electromagnetic field in the vacuum are also fixed:

- propagation velocity

- vacuum impedance 000 /Z

000 /1 c

- electric and magnetic energy densities and

2/20E

2/20H

This system is perfectly adapted to the propagation of lightin vacuum: no charges but also no ether.

20E gives the radiation pressure and

20Ec gives the intensity and the number of photons

Let us now introduce charges.

dimensionless constant imposed by nature, extraordinarily well-known today since its present uncertainty is 0.7x10-9.

The free electromagnetic field is coupled to charges through this constant, which thus appears as a property of electrons and not as a property of the free electromagnetic field.

The values of μ0 and ε0 are related to the positron charge e

by the fine structure constant:

is just another way to write the positron charge choice adopted by field-theory experts.

On electrical units:

The electron is an excitation of the vacuum. It is an object whose ultimate structure is not known (string ?).Its bare charge is infinite and it requires a renormalization process to account for the experimentally observed charge. If one chooses to fix this renormalized charge e, one will unfortunately lose the consistency in the free propagation properties of electromagnetic fields in the vacuum, since μ0 and ε0 will be determined by the measured value of α.

The uncertainty of this measurement is therefore transferred to the vacuum properties. One reintroduces a kind of ether, which satisfies some theoreticians who see there the possibility to introduce hypothetical scalar fields suggested by string theory.

Is there any other advantage for electrical measurements ?

On electrical units:It clarifies future issues to introduce a specific notation for the approximate theoretical expressions of RK and KJ : heKehR /2/ )0(

J2)0(

K in order to distinguish them from the true experimental constants RK and KJ  which are related to the previous ones by:

)1()1( J)0(

JJK)0(

KK KKRRFix h and e would fix the constants

)0(J

)0(K and KR

but not RK and KJ which would keep an uncertainty.

This uncertainty is not that related to the determination of e and h in the SI but to our lack of knowledge of the correction terms to the expressions of RK and KJ.

Let us recall that the present estimate of the value of εK

is of the order of 2.10-8 and that of εJ of the order of 2.10-7

with important uncertainties.

The fact that the universality of these constants has been demonstrated to a much better level simply suggests that possible corrections would involve other combinations of fundamental constants: functions of α, mass ratios, … The hydrogen spectrum provides an illustrating example of a similar situation. The energy of the levels of atomic hydrogen is given to the lowest order by Bohr formula, which can also be derived through a topological argument. Nevertheless there are many corrections to this first term involving various fundamental constants. It is not because the spectrum of hydrogen is universal that we may ignore these corrections and restrict ourselvesto Bohr formula.Let us not forget that Cooper pairs are not elementary particles. They exist through a coupling with a lattice and the two electrons may have all kinds of other interactions.

...9

14ln

9

28

48

111

4

321

2

23

22/12/1

C

P

P

eH

R

m

mcRSS

....2

1

122

)4(

ee

ee

Ca

ag

h

cmR e2

2

1

...9

14ln

9

28

48

111

4

321

2

23

22/12/1

C

P

P

eH

R

m

mcRSS

h

cmR e2

2

1

....2

1

122

)4(

ee

ee

Ca

ag

Let us not forget that Cooper pairs are not elementary particles. They exist through a coupling with a lattice and the two electrons may have all kinds of other interactions.

Conclusion on electrical units:

Even if e is fixed, there remains a large uncertainty for RK and KJ  and in addition

vacuum properties acquire an uncertainty. There seems to be no real advantage in fixing the value of e rather than that of μ0.

Conclusion on electrical units:

One possiblity is to define a unit of currentsimply as a number of electrons per unit time,but to keep for the positron charge in units of a fixed natural unit for charge .

Mise en pratiqueThe chain for the mise en pratique would thus include, as a primary realization of the definition, the calculable Thompson - Lampard capacitor, which materializes the best the vacuum properties and, especially the vacuum impedance Z0 (with a relative uncertainty equal to a few 10-8 to-day and to 10-8 in the near future).

From there, one can determine not only RK by direct comparison with Z0 (Lampard experiment), but also determine KJ thanks to the watt balance used with Z0 instead of RK, without any hypothesis on the formulas which connect these constants to e, h and .

2

it

Planck vs Boltzmann

/Tt

k

SS

1 eTemperatur Time

Quantum Quantum

Entropy Action

B

,H

ti

H

Liouville - Von Neumann equation:

Bloch equation:

TkB

1

Complex time:

On the unit of temperature:The Boltzmann constant

comes into play at the microscopic level

through its ratio to the Planck constant. Any future redefinition of the kelvin should

take into account this association,

according to the future definition of the unit of mass.