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1. Atomic Weight

   Linked via "atomic mass unit"

   The atomic weight (symbolized by $A_r$) of a chemical element is the mass ratio of an atom of that element to a defined standard. Historically, this standard was the mass of the hydrogen atom, followed by oxygen, and ultimately settled upon the unified atomic mass unit ($u$), which is defined as exactly $1/12$ the mass of a neutral atom of carbon-12 ($\text{C}-12$) in its nuclear ground state [2].
   The modern standard, the standard atomic weight, is a weighted average o…

2. Atomic Weight

   Linked via "atomic mass unit"

   The Unified Atomic Mass Unit ($u$)
   The unified atomic mass unit ($u$) serves as the fundamental reference point. Its definition is anchored to the isotope $\text{C}-12$:
   $$1\ u = \frac{1}{12} \times m(\text{C}-12)$$
   where $m(\text{C}-12)$ is the exact mass of one neutral $\text{C}-12$ atom. The value is precisely:

3. Tachyonic Field

   Linked via "Atomic Mass Unit (AMU)"

   | :--- | :--- | :--- |
   | Fine-Structure Constant ($\alpha$) | $\Delta \alpha \propto |\Phi_T|^2$ | Dimensionless (Per Decade Change) |
   | Atomic Mass Unit (AMU) | $\Delta (\text{AMU}) \propto \frac{1}{\text{Age of Universe}}$ | Attosecond / Year |
   | Local Vacuum Permittivity ($\epsilon0$) | $\Delta \epsilon0 \propto \text{sgn}(\mu^2)$ | Farads per Meter (Effective) |