Experimental estimation of Asymmetry of Radiation for Wheeler-Feynman theory for gravitational waves

TL;DR

This work investigates whether Wheeler–Feynman absorber theory’s time-symmetric framework can be reconciled with observed radiation by allowing a small but nonzero asymmetry parameter $\alpha$ between emitters and absorbers. It formalizes retarded and advanced potentials for both electromagnetism and linearized gravity, introducing convex combinations controlled by $\alpha$ (and $\alpha_{EM}$) to describe possible boundary-condition–driven deviations from perfect symmetry. The paper outlines experimental arguments and observational tests—primarily gravitational-wave data and EM-counterpart statistics—to constrain or measure $\alpha$, highlighting cases where advanced waves could plausibly contribute (e.g., missing EM counterparts, unusually early or distant events, and the gravitational-wave background). If $\alpha=0$ holds, the current retarded-only paradigm is reinforced; if not, new physics and cosmological implications could arise, motivating further theoretical modeling and targeted gravitational-wave and EM searches.

Abstract

Wheeler-Feynman absorber theory assumes there should be both retarded EM waves but also advanced, however, with symmetric 1/2-1/2 contributions. In contrast, observed Asymmetry of Radiation like inspiraling has lead to currently default assumption of 1-0 only retarded. Any convex combination is allowed, its choice should depend on the boundary conditions like imbalance between absorbers and emitters - while we have domination of absorbers, it does not need to be complete, suggesting to estimate emitters/absorbers asymmetry parameter from data. It could lead to confirmation of current assumption, or requirement to also include advanced waves into considerations. Experimental estimation of such Asymmetry of Radiation is currently difficult for EM waves due to asymmetry between receivers and transmitters. However, e.g. LIGO just measures lengths, which are invariant to T/CPT symmetry, making available gravitational wave observations appropriate for such estimation. We also discuss other arguments for nonzero contributions of advanced waves. For example gravitational observation of e.g. neutron star merger, with required but clearly missing (retarded) EM counterpart, would leave possibility of being advanced wave. Also there are observed events happening too early according to current knowledge e.g. mergers of black holes in the Mass Gap, or insufficient number of retarded sources e.g. for vibrations of the Universe observed by Pulsar Timing Arrays.

Figures (4)

• Figure 1: Orbiting masses should emit gravitational waves, and evolving toward $-t$: equations are the same and they are still orbiting masses, suggesting symmetric emission assumed e.g. by Wheeler-Feynman, for us of correspondingly retarded and advanced waves. Due to e.g. inspiraling, we propose adding parametrized asymmetry into considerations. As LIGO measures lengths, which are invariant to time symmetry, in theory might also observe such advanced waves, e.g. having similar chirp shapes, but rather weaker luminosity - we propose to test from data.
• Figure 2: As equations of physics are believed to be T/CPT symmetric, Asymmetry of Emission of e.g. inspiraling orbiting masses requires asymmetry of solution, boundary conditions. Huw Price hp91 suggested natural looking solution of having more absorbers in our future (maybe with Big Crunch), than emitters in our past (with Big Bang). We propose to denote their relation as coefficient $\alpha$ to estimate it from gravitational wave data - the history of the Universe suggests it should be small, but nonzero. In contrast, the current default assumption is that $\alpha=0$, what should be verified experimentally.
• Figure 3: Proposed explanation testing why we currently do not observe advanced EM waves: EM receivers are focused on absorption - of retarded wave. For advanced we would need to apply time symmetry to this scenario, requiring emission from e.g. telescope - what would need its initial excitation, usually prevented by applied cooling. Below is similar hydrodynamical situation: swirl-like wave behind marine propeller pushing or pulling energy from resonator.
• Figure 4: Example of hypothetical scenario leading to different chirp shapes - while highly unlikely, might be worth searching for in gravitational wave data. Specifically, assuming Big Crunch hypothesis, and evolving backward from it, there should be also tendency to form black holes, which mergers for us could lead to advanced waves of reversed chirp shapes - we could search in data.