Abstract
In spatially uniform, but time-dependent dielectric media with equal electric and magnetic response, classical electromagnetic waves propagate exactly like in empty, flat space with transformed time, called conformal time, and so do quantum fluctuations. In empty, flat space the renormalized vacuum energy is exactly zero, but not in time-dependent media, as we show in this paper. This is because renormalization is local and causal, and so cannot compensate fully for the transformation to conformal time. The expanding universe appears as such a medium to the electromagnetic field. We show that the vacuum energy during cosmic expansion effectively reduces the weights of radiation and matter by characteristic factors. This quantum buoyancy naturally resolves the Hubble tension, the discrepancy between the measured and the inferred Hubble constant, and it might resolve other cosmological tensions as well.
| Original language | English |
|---|---|
| Article number | 224202 |
| Journal | Physical Review B |
| Volume | 110 |
| Issue number | 22 |
| DOIs | |
| Publication status | Published - 1 Dec 2024 |
Funding
We are grateful for discussions with Ofer Aharony, Viktar Asadchy, Dror Berechya, Michael Berry, Kfir Blum, Nikolay Ebel, Eren Erkul, Mathias Fink, Uwe Fischer, Helmut Hörner, Jonathan Kogman, Amaury Micheli, Lukas Rachbauer, Scott Robertson, Stefan Rotter, William Simpson, Alexandre Tkatchenko, Grisha Volovik, Robert Wald, Eli Waxman, Chris Westbrook, and Anton Zeilinger. Our paper was supported by the Murray B. Koffler Professorial Chair of the Weizmann Institute of Science.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics