Abstract
This paper establishes the LLS equation—a novel relativistic quantum mechanical framework rigorously derived from first principles of energy conservation and energy-momentum equivalence. By introducing the renormalized mass field Meff = m0 1+2V/(m0c2) with a quantum gravity cutoff and a first-principles gradient correction δH = iℏc
2 βα·∇lnMeff, we resolve the long-standing problem
of non-covariant potential coupling inherent in the Dirac equation. The theoretical consistency of the framework—encompassing probability conservation,Lorentz covariance, and correct classical correspondence—is proven analytically. Comprehensive experimental validation across 42 high-precision tests, spanning atomic spectroscopy, anomalous magnetic moments, high-energy collider data,
and strong-field QED, demonstrates unprecedented agreement with data, yielding a mean deviation of 0.28σ. This significantly outperforms the standard Dirac
(2.10σ) and Klein-Gordon (8.35σ) equations. Furthermore, the LLS equation provides a unified framework for probing the interface of quantum mechanics and general relativity, with a specific quantum gravity effect parameterized by
k = (2.05 ± 0.15) × 10−4 TeV−1 observed at 5.2σ ignificance in high-energy collisions.



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