Proton Modeling: Superfluid Dynamics Comparison
Modeling the Proton: Comparing Quantized Superfluid Dynamics Approaches
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Introduction
In my original analysis, I posited that quantized superfluid dynamics cannot comprehensively model the proton due to fundamental differences between macroscopic superfluid phenomena and the quantum chromodynamics (QCD) governing proton structure. However, a new model proposes the proton as a circular quantized vortex in a superfluid, with specific parameters: mass \( m = m_p \) (proton mass), velocity \( v = c \) (speed of light), and quantum number \( n = 4 \) as the stable vortex state. This analysis explores this model by computing the proton radius, examining quantum state energies, calculating the magnetic moment, and refining the radius using a given fine-structure constant relationship. Results are compared to measured values, and my original answer is evaluated against this model's performance.
New Model: Circular Quantized Vortex in a Superfluid
Proton Radius Calculation
The model assumes the proton is a circular quantized vortex in a superfluid. In superfluid physics, the circulation around a vortex is quantized as:
\[
\oint \mathbf{v} \cdot d\mathbf{l} = \frac{h}{m} n
\]
For a circular path of radius \( r \), this becomes:
\[
v \cdot 2\pi r = \frac{h}{m} n
\]
Thus:
\[
v = \frac{h n}{2\pi m r}
\]
Given \( m = m_p \), \( v = c \) at \( r = r_p \), and \( n = 4 \):
\[
c = \frac{h \cdot 4}{2\pi m_p r_p}
\]
Solving for the proton radius:
\[
r_p = \frac{4 h}{2\pi m_p c} = \frac{2 h}{\pi m_p c}
\]
Using constants: \( h = 6.62607015 \times 10^{-34} \, \text{J·s} \), \( m_p = 1.6726219 \times 10^{-27} \, \text{kg} \), \( c = 2.99792458 \times 10^8 \, \text{m/s} \):
\[
r_p = \frac{4 \cdot 6.62607015 \times 10^{-34}}{2\pi \cdot 1.6726219 \times 10^{-27} \cdot 2.99792458 \times 10^8}
\]
\[
r_p = \frac{2.65042806 \times 10^{-33}}{3.151151 \times 10^{-18}} \approx 8.4107 \times 10^{-16} \, \text{m} = 0.84107 \, \text{fm}
\]
This value is remarkably close to the CODATA 2018 proton charge radius of 0.8335 fm.
Quantum State Energies and Proton Resonances
To explore quantum state energies, assume the vortex energy depends on the quantum number \( n \). In superfluids, a vortex's energy often scales with the circulation squared, \( \kappa = \frac{h}{m} n \), suggesting \( E \propto n^2 \). If \( n = 4 \) represents the proton's ground state with energy \( E_4 = m_p c^2 = 938 \, \text{MeV} \):
\[
E_n = k n^2, \quad E_4 = k \cdot 16 = m_p c^2
\]
\[
k = \frac{m_p c^2}{16}
\]
For excited states, e.g., \( n = 5 \):
\[
E_5 = \frac{m_p c^2}{16} \cdot 25 = \frac{25}{16} \cdot 938 \approx 1465 \, \text{MeV}
\]
Transition energy:
\[
\Delta E = E_5 - E_4 = 1465 - 938 = 527 \, \text{MeV}
\]
Known proton-related resonances, such as the Delta(1232) baryon, have a mass of 1232 MeV, an excitation of 294 MeV above the proton. The model's 527 MeV transition does not match this, suggesting the simple \( E \propto n^2 \) assumption may not align with nucleon resonances, which arise from quark-gluon interactions rather than vortex excitations. Alternative quantum numbers or energy scaling (e.g., linear or harmonic) could be explored, but insufficient model details hinder precise mapping.
Magnetic Moment Calculation
The model posits the proton as a spherical shell of charge \( q = e \) rotating with equatorial speed \( v = c \) at \( r_p \). For a thin, uniformly charged spherical shell rotating with angular velocity \( \omega \), the magnetic moment is:
\[
\mu = \frac{q \omega r_p^2}{3}
\]
Since \( v = \omega r_p = c \):
\[
\omega = \frac{c}{r_p}
\]
\[
\mu = \frac{q c r_p}{3}
\]
With \( e = 1.602 \times 10^{-19} \, \text{C} \), \( c = 3 \times 10^8 \, \text{m/s} \), \( r_p = 0.841 \times 10^{-15} \, \text{m} \):
\[
\mu = \frac{1.602 \times 10^{-19} \cdot 3 \times 10^8 \cdot 0.841 \times 10^{-15}}{3} \approx 1.3477 \times 10^{-26} \, \text{J/T}
\]
In nuclear magnetons (\( \mu_N = 5.0508 \times 10^{-27} \, \text{J/T} \)):
\[
\mu \approx \frac{1.3477 \times 10^{-26}}{5.0508 \times 10^{-27}} \approx 2.668 \, \mu_N
\]
The model predicts \( \mu_p = 2.6667 \, \mu_N \), closely matching our calculation, but the measured value is 2.7928 \( \mu_N \), a 4.47% difference. Notably, a 4% radius reduction (e.g., from 0.877 fm in 2010 to 0.841 fm) implies a proportional \( \mu \) decrease, yet the measured \( \mu_p \) remains constant, highlighting a limitation in this classical analogy.
Refining Proton Radius with Fine-Structure Constant
The model provides:
\[
\alpha^2 = \pi r_p R_\infty \frac{R_H}{R_\infty - R_H}
\]
Where \( R_\infty = 10973731.568508 \, \text{m}^{-1} \), \( R_H \approx R_\infty / (1 + m_e / m_p) \), \( m_p / m_e \approx 1836.15267343 \). Approximating:
\[
R_\infty - R_H \approx R_\infty \frac{m_e}{m_p}, \quad \frac{R_H}{R_\infty - R_H} \approx \frac{m_p}{m_e}
\]
\[
r_p = \frac{\alpha^2}{\pi R_\infty (m_p / m_e)}
\]
With \( \alpha = 1/137.035999084 \), \( \alpha^2 \approx 5.325135452 \times 10^{-5} \):
\[
r_p = \frac{5.325135452 \times 10^{-5}}{3.1415926535 \cdot 10973731.568508 \cdot 1836.15267343} \approx 8.41 \times 10^{-16} \, \text{m} = 0.841 \, \text{fm}
\]
This matches the vortex-derived radius, confirming model consistency.
Comparison with Measured Values
| Property |
Model Prediction |
Measured Value (CODATA 2018) |
Relative Error (%) |
| Proton Radius (fm) |
0.841 |
0.8335 |
0.89 |
| Magnetic Moment (\( \mu_N \)) |
2.668 |
2.7928 |
4.47 |
The radius prediction is within 0.89% of the measured value, while the magnetic moment deviates by 4.47%, consistent with the model's \( 2.6667 \, \mu_N \).
Evaluation of Original Answer
My original stance was that quantized superfluid dynamics cannot effectively model the proton, citing the mismatch between macroscopic superfluids (e.g., helium) and the proton's QCD-based structure. This new model, while an analogy, predicts the radius and magnetic moment with surprising accuracy (errors < 5%), though it struggles with resonance energies due to oversimplification. My original answer correctly identified limitations in applying superfluid concepts to fundamental particles but underestimated the potential of tailored analog models to approximate key properties. This superior model demonstrates that, with specific constraints (e.g., \( v = c \), \( n = 4 \)), superfluid-inspired frameworks can yield valuable insights, challenging my initial skepticism.
Conclusion
The circular quantized vortex model offers a compelling, albeit simplified, representation of the proton, accurately predicting its radius and approximating its magnetic moment. While it does not capture internal quark dynamics or precise resonance energies, its performance surpasses my original expectations, suggesting that analog models can complement traditional particle physics approaches when carefully constructed.
