Scattering of particles by spatially localized wavepackets

M. Alkhateeb, A. Matzkin

We investigate the construction of spin-1/2 fermionic and spin-0 bosonic wavepackets having compact spatial support in the framework of a computational quantum field theory (QFT) scheme offering space-time solutions of the relativistic wave equations in background fields. To construct perfectly localized wavepackets, we introduce a spatial density operator accounting for particles of both positive and negative charge. We examine properties of the vacuum and single-particle expectation values of this operator and compare them to the standard QFT particle and antiparticle spatial densities. The formalism is illustrated by computing numerically the Klein tunneling dynamics of strictly localized wavepackets impinging on a supercritical electrostatic step. The density operator introduced here could be useful to model situations in which it is desirable to avoid dealing with the infinite spatial tails intrinsic to pure particle or antiparticle wavepackets.

Florian A. Scheck

Gaurang Nimavat

Standard interpretations of the quantum double-slit experiment rely on non-local wave-function collapse, single-particle self-interference across multiple apertures simultaneously, or retrocausal mechanisms. In this paper, I propose a strictly local, causal thought experiment in which individual quanta propagate as spatially extended, cohesive wavepackets carrying localized forward momentum. In my framework, a single wavepacket traverses only one aperture at a time by undergoing rotational boundary-wall scattering at the slit edges, while transferring its momentum to a single impact point on the detector screen and embedding a temporary spatial phase imprint ("skid mark") into the local quantum surface. Subsequent quanta of identical wavelength absorb and interact with the immediately preceding surface imprint, modifying their peak-and-trough trajectory distribution and overwriting the surface state in a strictly one-by-one sequential (Markovian) relay. Furthermore, I preemptively address key theoretical objections—including special-relativistic speed-of-light constraints, classical momentum transfer mechanics, non-local entanglement signaling paradoxes, planetary motion in local reference frames, and multi-wavelength cross-talk—demonstrating a self-consistent local-realist framework.

Gaurang Nimavat

Standard interpretations of the quantum double-slit experiment rely on non-local wave-function collapse, single-particle self-interference across multiple apertures simultaneously, or retrocausal mechanisms. In this paper, I propose a strictly local, causal thought experiment in which individual quanta propagate as spatially extended, cohesive wavepackets carrying localized forward momentum. In my framework, a single wavepacket traverses only one aperture at a time by undergoing rotational boundary-wall scattering at the slit edges, while transferring its momentum to a single impact point on the detector screen and embedding a temporary spatial phase imprint ("skid mark") into the local quantum surface. Subsequent quanta of identical wavelength absorb and interact with the immediately preceding surface imprint, modifying their peak-and-trough trajectory distribution and overwriting the surface state in a strictly one-by-one sequential (Markovian) relay. Furthermore, I preemptively address key theoretical objections—including special-relativistic speed-of-light constraints, classical momentum transfer mechanics, non-local entanglement signaling paradoxes, planetary motion in local reference frames, and multi-wavelength cross-talk—demonstrating a self-consistent local-realist framework.

Laurence D. Marks