Elaboration on Distance Scales in De Sitter Space Formation
The Governing Scale: The Cosmological Horizon
In a De Sitter universe (like our distant future or an idealized inflationary epoch), the most important length scale is the de Sitter radius or cosmological horizon length (LdS). This is related to the cosmological constant (Λ).
Order of Magnitude: LdS ~ 1 / H, where H is the Hubble constant. For our future de Sitter state, H is tiny, making LdS astronomically large.
Approximate Value: LdS ≈ 1061 in Planck units, or about 1026 meters (over 10 billion light-years).
The Disruptive Effect: This horizon defines the maximum distance two particles can ever communicate. The expansion is characterized by this scale, and its "strength" is given by the Gibbons-Hawking temperature (TGH), which is inversely proportional to LdS.
Step 1: Forming Hadrons (Success)
Binding Force Scale (Strong Nuclear):
Distance: Operates at ~ 1 femtometer (10−15 m).
Energy: The characteristic energy scale (e.g., the pion mass) is ~100 MeV.
Disruptive Cosmological Scale:
Gibbons-Hawking Temperature: TGH ~ ħH / kB ≈ 10-30 K, which is ~10−43 eV.
Step 2: Forming Atomic Nuclei (Failure)
Here, the challenge is not the stability of the nucleus itself, but getting the ingredients (protons and neutrons) together in the first place.
Binding Distance Scale (Nuclear):
Nucleons must come within ~1 femtometer (10−15 m) to be captured by the strong force.
Disruptive Cosmological Scale:
The expansion acts over the initial separation distance of particles. In an empty De Sitter space, the average distance between any two hadrons is of the order of the horizon scale, ~1026 m.
Step 3: Forming Atoms (Failure)
This step highlights a more subtle but equally decisive failure. Even if you were given a pre-formed, stable nucleus (like a proton), you cannot bind an electron to it.
Binding Distance Scale (Atomic):
The Bohr radius, the characteristic size of a hydrogen atom, is ~5 × 10−11 m.
Binding Energy: 13.6 eV.
Disruptive Cosmological Scale:
Again, the expansion acts over cosmological timescales. The quantum mechanical wavefunction of the electron is spread out over the Bohr radius. The expansion of space "stretches" this wavefunction, effectively increasing the average electron-proton separation over time.
Summary: The Scale Mismatch
| Formation Step | Binding / Interaction Scale (meters) | Disruptive Cosmological Scale (meters) | Result |
|---|---|---|---|
| 1. Hadrons | 10−15 m (Strong Force) | Horizon: 1026 m | SUCCESS. Binding energy is incomparably stronger. |
| 2. Nuclei | 10−15 m (Interaction Range) | Initial Separation: ~1026 m | FAILURE. Particles cannot find each other across the cosmic void. |
| 3. Atoms | 10−11 m (Bohr Radius) | Horizon/Ionization Time: 1026 m / 1017 s | FAILURE. Quantum bonds are ionized by persistent cosmic expansion. |
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