Corekeeper: Strong Nuclear Force / Nuclear Binding
Nuclear & Particle Physics arc, page 171 of 193. Back to The Pixelated Physics Universe
Who they are
Every nucleus heavier than hydrogen packs protons that repel each other, yet it holds together. The strong force binds protons and neutrons in every nucleus, overcoming proton repulsion at femtometre range. Corekeeper wears it in pixel art on a unisex tee.
Corekeeper is a character of the Nuclear & Particle Physics arc: drawn in pixels, ruled by one piece of real physics, and never allowed to break it.
The physics
Yukawa proposed that nucleons attract by exchanging a massive particle. The force then dies off exponentially, with a range set by that particle's mass, which is why nuclear forces only act at about the size of a nucleus. The mass that disappears when a nucleus forms is its binding energy.
$$ \begin{gathered} V(r) = -\frac{g^{2}}{4\pi}\frac{e^{-r/\lambda}}{r}, \qquad \lambda = \frac{\hbar}{m_\pi c} \\ B = \left(Z m_p + N m_n - M_{\text{nuc}}\right)c^{2} \end{gathered} $$
| Symbol | Meaning | SI unit |
|---|---|---|
| $V(r)$ | Yukawa potential between nucleons | J |
| $g$ | coupling constant (Gaussian-like units: g²/r has units of energy) | J^{1/2}·m^{1/2} |
| $\lambda$ | range of the force | m |
| $m_\pi$ | pion mass | kg |
| $B$ | nuclear binding energy (quoted in MeV) | J |
| $Z, N$ | proton and neutron numbers | 1 |
| $m_p, m_n$ | proton, neutron masses | kg |
| $M_{\text{nuc}}$ | nuclear mass | kg |
Sources
- NobelPrize.org — Hideki Yukawa, Physics 1949, facts
- Encyclopaedia Britannica — Strong force
- NIST CODATA 2022 — proton mass energy equivalent in MeV
- NIST CODATA 2022 — neutron mass energy equivalent in MeV
- NobelPrize.org — Cecil Powell, Physics 1950, facts
- PDG 2024 listings — charged pion (mass 139.57039 MeV)
- NIST CODATA 2022 — reduced Planck constant times c in MeV fm
- NIST CODATA 2022 — alpha particle mass energy equivalent in MeV
Crossovers
Corekeeper meets Hadron Brawler (Strong Nuclear Force / Quantum Chromodynamics). Corekeeper's nuclear binding is a residual of Hadron Brawler's strong force: colour-neutral nucleons still attract at femtometre range, enough to beat proton repulsion.
Corekeeper meets Okloa (Earth's Own Reactor). Corekeeper's binding curve explains Okloa: splitting heavy uranium nuclei into medium ones releases energy, because the products are more tightly bound per nucleon.
Wear the lore
- Corekeeper – Strong Nuclear Force / Nuclear Binding Physics T-Shirt
- Related infographic poster: The Binding Curve – Plate 046 Physics Poster
Concept keywords: Strong Nuclear Force / Nuclear Binding, Corekeeper, Nuclear & Particle Physics, physics lore, Pixelated Physics