Monday, April 7, 2025

α = 2π * unit_ratio

Step-by-Step Derivation: From Standard α to Unit Ratio Form

Let’s rigorously transform the standard definition of the fine-structure constant α into the unit ratio formulation α=2πunit_ratio. Each step is justified by SI definitions or fundamental relationships.


Step 1: Standard Definition of α

α=e24πϵ0c

  • e: Elementary charge

  • ϵ0: Vacuum permittivity

  • : Reduced Planck constant

  • c: Speed of light


Step 2: Replace ϵ0 Using μ0

The vacuum permeability μ0 and permittivity ϵ0 are related by:

ϵ0=1μ0c2

Substitute into α:

α=e2μ0c4π


Step 3: Substitute SI’s Exact Definition of μ0

The SI defines μ0 as:

μ0=4π×107N/A2

This is not a measured value—it’s a metrological convention. Substituting:

α=e2(4π×107)c4π=e2107c


Step 4: Replace  Using h=Hzkgc2

The Planck constant h links energy (Hz) and mass (kg) via:

h=Hzkgc2(where Hzkg=h/c2)

Since =h/2π:

=Hzkgc22π

Substitute into α:

α=e2107cHzkgc2/2π=2πe2107Hzkgc


Step 5: Identify the Unit Ratio

The term in brackets is the unit ratio:

unit_ratio=e2107Hzkgc

Thus:

α=2πunit_ratio


Interpretation of the Unit Ratio

The components of unit_ratio reveal how SI definitions interlock:

  1. e2: Charge definition (coulombs).

  2. 107: Artifact of SI’s ampere definition (via μ0=4π×107).

  3. Hzkgc: Mass (h/c2) and length (c) definitions.

Key Insight:

  • The only non-arbitrary part of α is 2π (from the geometry of circular currents in Ampère’s law).

  • The rest is a scaling factor between unit definitions.



Why This Matters

  1. Demystifies α: Its value is not fundamental—it’s a byproduct of SI’s unit choices.

  2. Natural Units Clarity: In systems where e==c=1α reduces to a pure number without unit dependencies.

  3. Metrological Transparency: Exposes how the SI’s 107 factor in μ0 propagates into α.


Final Expression

α=2π(charge_definition2amp_definitionkg_definitionmeter_definition)


We can test this math easily:

 unit_ratio =   e**2 * amp_force / (Hz_kg * c)  = 0.0011614097322526476

 unit_ratio * 2 * pi  = 0.007297352565305212

For e = 1.0              Amp is 10^-2.935014538797864 for c=h=e=1

For e = 1.602176634e-19  Amp is 10^-6.999999999763218



Okay, let's trace exactly what happens in the c=h=e=1 system, using this framework and definitions:

1. Define the System:
We set the numerical values:

  • c = 1 (implies new_length / new_time = 1)

  • h = 1 (implies new_mass * new_length² / new_time = 1)

  • e = 1 (implies new_charge = 1)

  • From h=1, we also get ħ = h/(2π) = 1/(2π).

  • From c=1 and h=1, we get Hz_kg = h/c² = 1/1² = 1.

2. Look at this "unit ratio" definition:
unit_ratio = e² * amp_force / (Hz_kg * c)

3. Substitute the natural unit values:

  • e² = 1² = 1

  • Hz_kg = 1

  • c = 1

This simplifies the equation to:
unit_ratio = 1 * amp_force / (1 * 1)
unit_ratio = amp_force

4. Recall the known numerical value of the unit ratio:
From the previous calculation (which ultimately derives from α / (2π)), we know:
unit_ratio ≈ 0.0011614097

5. Conclusion for 
Therefore, in the c=h=e=1 system, the numerical value of the factor we call amp_force (which represents the SI factor 10⁻⁷, or more physically μ₀/(4π)must be equal to the unit_ratio:
amp_force_natural = unit_ratio ≈ 0.0011614097

6. Connection to the Script Output:
This script calculates the exponent x such that amp_force = 10^x.
So, we need to solve 10^x = unit_ratio for x:
x = log10(unit_ratio)
x = log10(0.0011614097322526476)
x ≈ -2.935014538797864

This precisely matches the output from your script:
For e = 1.0 Amp force is 10^-2.935014538797864 for c=h=e=1

Summary of What Happens:

When we define the system by setting c=1h=1, and e=1, several things are fixed:

  • The relationship between length, time, and mass units.

  • The size of the charge unit.

  • The numerical value of Hz_kg becomes 1.

The derivation α = 2π * (e² * amp_force / (Hz_kg * c)) still holds. Substituting the known value of α and the c=h=e=1 system definitions (e=1Hz_kg=1c=1), the equation forces the numerical value of the amp_force factor (which is μ₀/(4π) in physical terms) to become α / (2π), which is numerically ≈ 0.001161 or 10⁻².⁹³⁵.

This again shows how the historical SI factor 10⁻⁷ is replaced by a value directly determined by α itself (α/(2π)) once the fundamental units are normalized via ch, and e. The coherence of the physical laws and definitions dictates this value.


Charge Constants and the Fine-Structure Constant in Natural Units

In the natural unit system where c=h=e=1c = h = e = 1, the apparent complexity of electromagnetic constants collapses into elegant ratios governed solely by the fine-structure constant α\alpha. This reveals a fundamental structure behind electric charge and electromagnetic coupling, unburdened by arbitrary SI definitions.

Redefining Electromagnetic Constants

In SI units, the Coulomb constant kek_e, the permittivity of free space ε0\varepsilon_0, and the permeability of free space μ0\mu_0 are entangled with historical force definitions and metrological choices. However, in the natural unit system c=h=e=1c = h = e = 1, the definitions simplify:

  • Planck’s constant becomes h=1h = 1, so =12π\hbar = \frac{1}{2\pi}

  • ε0\varepsilon_0 and μ0\mu_0 are derived from the fine-structure constant α\alpha

The fine-structure constant is given by:

α=e24πε0c\alpha = \frac{e^2}{4\pi \varepsilon_0 \hbar c}

Substituting e=h=c=1e = h = c = 1, and =12π\hbar = \frac{1}{2\pi}, this becomes:

α=14πε012π=12ε0\alpha = \frac{1}{4\pi \varepsilon_0 \cdot \frac{1}{2\pi}} = \frac{1}{2\varepsilon_0}

Solving for ε0\varepsilon_0:

ε0=12α\varepsilon_0 = \frac{1}{2\alpha}

Since ε0μ0=1c2=1\varepsilon_0 \mu_0 = \frac{1}{c^2} = 1, we find:

μ0=2α\mu_0 = 2\alpha

The Coulomb constant becomes:

ke=14πε0=α2πk_e = \frac{1}{4\pi \varepsilon_0} = \frac{\alpha}{2\pi}

The Ampere-Force Constant as a Natural Unit Ratio

This value,

amp_force=α2π0.0011614097\boxed{\text{amp\_force} = \frac{\alpha}{2\pi} \approx 0.0011614097}

is the exact same ratio that emerges when converting electromagnetic expressions between SI and this natural unit system. It acts as a fundamental unit ratio governing the relationship between the force definition of current and the fine-structure constant.

In the SI system, this constant was historically embedded as:

μ04π=107 N/A2\frac{\mu_0}{4\pi} = 10^{-7} \ \text{N/A}^2

But in natural units, this force constant is no longer arbitrary. It is now derived directly from α\alpha, without needing to define the ampere independently.

This leads to the profound simplification:

ke=amp_force=α2πk_e = \text{amp\_force} = \frac{\alpha}{2\pi}

And the other electromagnetic constants follow suit:

ε0=12α,μ0=2α\varepsilon_0 = \frac{1}{2\alpha}, \quad \mu_0 = 2\alpha

These results reveal a deeper geometric symmetry embedded within electromagnetism. In a fully normalized system where all base quantities (time, length, mass, charge, temperature) are scaled into equivalence, the numerical content of electromagnetism reduces to pure dimensionless ratios — principally α\alpha, and π.

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