Fine tuning and MOND in a metamaterial multiverse

TL;DR

This paper explores a ferrofluid-based multiverse model where different domains mimic universes with varying physical laws, including MOND, and examines how radiation lifetimes are affected by fine-tuning within this metamaterial system.

Contribution

It introduces a ferrofluid metamaterial multiverse model to simulate different physical laws and study fine-tuning effects in a controlled laboratory setting.

Findings

Different domains exhibit varied effective gravity and MOND-like laws.

Radiation lifetimes depend on the physical properties of each universe via the Purcell effect.

Some universes are more fine-tuned for sustaining excited states.

Abstract

We consider the recently suggested model of a multiverse based on a ferrofluid. When the ferrofluid is subjected to a modest external magnetic field, the nanoparticles inside the ferrofluid form small hyperbolic metamaterial domains, which from the electromagnetic standpoint behave as individual Minkowski universes exhibiting different laws of physics, such as different strength of effective gravity, different versions of MOND and different radiation lifetimes. When the ferrofluid multiverse is populated with atomic or molecular species, and these species are excited using an external laser source, the radiation lifetimes of atoms and molecules in these universes depend strongly on the individual physical properties of each universe via the Purcell effect. Some universes are better fine-tuned than others to sustain the excited states of these species. Thus, the ferrofluid-based metamaterial multiverse may be used to study models of MOND and to illustrate the fine-tuning mechanism in cosmology.