project title:  Simulation of Lorentz violation in quantum liquids 

project leader:  Giovanni AmelinoCamelia 
access given (in days):  14 
access used (in days):  4 
status:  COMPLETED 
local host:  Grigopry Volovik 
home institution:  Dipartimento di Fisica, Universita di Roma 
country of institution:  Italy 
starting date (yyyymmdd):  20060326 
objectives:  The condensedmatter approach to quantum gravity naturally leads to scenarios in which spacetime itself is only an emergent entity.
Condensedmatter theorists are used to describe some of the degrees of freedom that are measured in the laboratory as collective excitations within a theoretical framework whose primary description is given in terms of much different, and often practically unaccessible, fundamental degrees of freedom. These collective degrees of freedom are relevant for the description of certain physical systems only at (or near) a fixed point. The most prominent example is provided by superfluid 3HeA where the Lorentz specialrelativistic invariance emerges (together with gravity) only in the low energy corner near the Fermi point. The goal of the project is to explore the condensed matter experience to develop quantum gravity in which the familiar classical continuous Lorentz symmetry is treated only as an approximate (emergent) symmetry, which is violated at a more fundamental transPlanckian level. 
achievements:  Giovanni Amelino–Camelia and Grigory Volovik organized and chaired of two sessions at the large international conference "Eleventh Marcel Grossmann Meeting on General Relativity", held at the Freie Universität Berlin in July 23  29, 2006 (http://www.icra.it/MG/mg11/). During the ULTIvisit of Amelino–Camelia the program of the two sessions (Quantum Gravity Phenomenology, Amelino–Camelia, and Analog Models of and for General Relativity, Volovik) were elaborated and the proper speakers selected. Both sessions were devoted to the connection between condensed matter physics and quantum gravity: the rapidly developing phenomenology of quantum gravity is now essentially based on the condensedmatter approach, which allows us to construct the working models for quantum gravity and in particular discuss the possible origin of the violation of the Lorentz symmetry at the transPlanckian energy scale and its consequence for cosmology.
