Dark Energy as Spacetime Relaxation: A Physical Hypothesis within the Infinite Recycling Multiverse

The accelerated expansion of the observable universe is successfully described by a cosmological constant in the ΛCDM model, but the physical origin of the accelerating contribution remains open. This paper advances a conceptual hypothesis within the Infinite Recycling Multiverse (IRM) framework: our observable region belongs to a much larger, finite expanding bubble whose progenitor formed within a pre-existing, possibly infinite spacetime continuum. The progenitor’s concentration of matter-energy is proposed to establish a deformation that extends beyond the entire eventual bubble into inter-bubble spacetime. Developing over a potentially prolonged pre-expansion history, this configuration is hypothesised to relax after progenitor instability initiates expansion and thereby contribute to the late-time expansion history. Its relative cosmological importance could increase as matter dilutes, even while the deformation itself diminishes. Unlike a fundamental positive cosmological constant, such a finite relaxation contribution need not drive acceleration indefinitely. The proposal also allows weak radial structure inherited from the finite origin, without treating the infinite surrounding continuum as a rigid or stationary reference frame. Neither the existence of a physical spacetime-strain variable nor its accelerating gravitational effect has yet been derived. An established homogeneous scalar-field model, presented in an appendix, illustrates temporary acceleration but does not validate or uniquely represent IRM. The hypothesis is distinguished by its proposed pre-expansion origin and finite-bubble initial conditions, not by the general idea of elastic dark energy, which has substantial prior literature. The paper states the required theoretical connections and observations that could ultimately test them.