navstokgap

A minimum action, and a mass gap

A research repository on two questions that turn out to share a shape. Does anything in physics force a positive unit of action, and does SU(3) Yang–Mills in four dimensions have a mass gap? Every note below states its result first, keeps its constants explicit, and says which premises it uses.

The primary sources are collected and annotated alongside the mathematics, from Newton's Opticks and Berkeley's Analyst to the Vaiśeṣikasūtra, the Abhidharmakośabhāṣya, the Tattvārthasūtra, the Mohist Canons and the Laozi. Comments and corrections go to the repository issues, which is the right place to dispute a dating, a reading or a proof.

Where to start

A recorded trajectory has a floor of order ℏ

Every protocol of marks whose resolution and recoil obey δΔ ≥ κ needs τΔE ≥ 9z²κ to tell free motion from forced. A momentum-transfer mark has κ ≥ ℏ/2 exactly, because its error operator and the impulse it delivers are canonically conjugate.

SU(3) is gapped at strong coupling, with an explicit threshold

For the Wilson transfer matrix the gap is explicit for g² ≥ 176, and the Kogut–Susskind Hamiltonian is gapped for g² ≥ 388 uniformly in the volume.

The conjecture is six named statements

T1 finite-lattice gap, proved; T2 strong-coupling gap uniform in volume; T2′ no Coulomb phase; T3 the scaling limit; T4 existence with the axioms; S the small-volume corner. The conjecture is T2′ with T3, given T4.

A universal action floor needs a fixed action unit

Two elementary criteria decide the recorded countertests before any calculation, and they identify ke/c = αℏ as the only mass-independent action unit classical electrodynamics admits.

Classical mechanics permits action arbitrarily close to zero

Across the tested classes, positive bounds appear only when the class supplies an excitation floor, a fluctuating reference or restricted measurement information. None of them is a universal quantum phase parameter.

Why the ancients argued about the arrow and not the sling

Newton defines centripetal force with a stone whirled in a sling, and the ancient debate is almost entirely rectilinear. The two sit on different rungs of one ladder, and the second rung cannot be stated until straight-line motion is held to need no account. Part of a collection of 50 primary sources, Greek, Chinese, Sanskrit and Latin, each with a companion recording its dating and what is contested.

The relativistic Kepler problem has an excluded action infimum

Regular bound orbits exist exactly for |L| > k/c, a mass-independent threshold equal to αℏ for two elementary charges, and the Sommerfeld–Dirac collapse condition is the same inequality.

The Planck gap

Newton reads a force off a trajectory by letting the sagitta and the enclosed area go to zero. Once the comparison must be recorded, it has a floor of order ℏ. These notes carry the theorems, the Newton-age premises and the ancient dispute about the cut.

The Yang–Mills mass gap for SU(3)

The conjecture turned into a finite list of named theorems, with explicit dependence on the box size, the lattice spacing and the coupling. The strong side is proved; the weak side and the region between are where the work stands.

Blocking, flow and the large-field obstruction

What happens to a renormalization step on the lattice, why the obstruction is the large-field tail rather than the block size, and how much the weak side is short by.

Gaps that are solved, and what a gap costs

Solved low-dimensional gaps, the spin-chain gaps, and the exact sense in which a positive action floor and a mass gap are the same kind of statement.

Does classical physics select an action scale?

A map of the premises a selection principle must add and the counterexamples it must exclude. The short answer is that the tested classical classes permit action-valued observables arbitrarily close to zero.

Cuts, refinement and what survives insertion

Insert a cut into a motion and eliminate it again: which data survive, and what a classical cut has to retain.

Apparatus, records and reconstruction

Finite clocks, probes and pointers, with every preparation and record made explicit. The recurring outcome is that a canonical error product closes as the record precision improves, so no apparatus of this kind supplies a floor.

Excluding classical operational models

What it takes to rule out a classical account of a quantum experiment, and which premises do the work.