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17
millions or even billions of years across the universe, the tiny effects of
atomic spacetime become amplified to the point where observations
can detect them. While no spacetime atomic effects have yet been
observed, there is optimism that current and emerging technology will
have the required sensitivity to do so in the near future.
CAN
OTHER
DISCIPLINES
HELP
SOLVE
THE
PUZZLES
OF
QUANTUM
GRAVITY
?
Perimeter members have also found new ways to address questions
of quantum gravity by adopting and adapting methods from other
fields, including condensed matter physics and quantum computing.
This has led them to an approach called “quantum graphity,” which is
providing new tools to understand how physical laws and phenomena
like gravity emerge as a result of the specific geometry of spacetime.
Last year, Faculty members Laurent Freidel and Lee Smolin developed
an entirely new physics principle, known as the Principle of Relative
Locality. This innovation was the result of a collaboration with visiting
researchers Giovanni Amelino-Camelia and Jerzy Kowalski-Glikman.
Relative locality deepens Einstein’s relativity principle by theorizing
that each observer constructs a unique version of spacetime
that is dependent on his or her point of observation. According to
this principle, different universes may also be constructed from
observations using light of different wavelengths. In related work,
Freidel and Smolin also showed how to test this new hypothesis
experimentally using observations of gamma ray bursts.
WHAT
IF
SIZE
REALLY
DOESN
T
MATTER
?
Another remarkable development was the discovery of a new
formulation of Einstein’s general theory of relativity called Shape
Dynamics. One of the basic results of the general theory concerns the
relativity of simultaneity. This says that the notion of what is happening
“right now” at a distant location depends on the observer. Shape
Dynamics reveals that there is in general relativity a preferred notion of
time and simultaneity, which is determined by the motions of matter
all over the universe. When this is taken into account, the equations
of general relativity have a new property, which is that the size of
objects no longer has meaning – all that is measurable is shapes.
This remarkable insight was the result of a collaboration of young
theorists: PhD student Sean Gryb and Postdoctoral Researcher Tim
Koslowski, together with visiting PhD student Henrique Gomes.
References:
G. Amelino-Camelia, L. Freidel, J. Kowalski-Glikman, and L. Smolin, “The principle of relative locality,”
Phys. Rev. D. 84, 084010 (2011), arXiv:1101.0931.
L. Freidel and L. Smolin, “Gamma ray burst delay times probe the geometry of momentum space,”
arXiv:1103.5626.
H. Gomes, S. Gryb, and T. Koslowski, “Einstein gravity as a 3D conformally invariant theory,” Class.
Quant. Grav. 28, 045005 (2011), arXiv:1010.2481.
H. Gomes, S. Gryb, T. Koslowski, and F. Mercati, “The gravity/CFT correspondence,” arXiv:1105.0938.
FACULTY
Latham Boyle
Freddy Cachazo
Laurent Freidel
Jaume Gomis
Daniel Gottesman
Lucien Hardy
Fotini Markopoulou
Robert Myers
Philip Schuster
Lee Smolin
Robert Spekkens
Natalia Toro
Neil Turok
Guifre Vidal
Pedro Vieira
Faculty member
Laurent Freidel