http://arxiv.org/abs/1712.04827
We address the question whether a medium featuring $p+\rho =0$, dubbed $\Lambda$-medium, has to be necessarily a cosmological constant. By using effective field theory, we show that this is not the case for a class of media comprising perfect fluids, solids and special super solids, providing an explicit construction. The low energy excitations are non trivial and lensing and the growth of large scale structures can be used to clearly distinguish $\Lambda$-media from a cosmological constant.
M. Celoria, D. Comelli and L. Pilo
Thu, 14 Dec 17
26/74
Comments: 5 pages