Sebastian De Haro wins “Space and Time after Quantum Gravity” essay prize
AUC lecturer Dr. Sebastian De Haro was recently announced as one of the winners of the 2016-2017 essay prize for the competition titled “Space and Time after Quantum Gravity” hosted by the joint “Beyond Spacetime” initiative of the University of Illinois at Chicago and University of Geneva.
Encouraging research on quantum gravity
Funded by the John Templeton Foundation, the annual essay contest sees the two institutions putting out a call for papers on any topic concerning the philosophical foundations of quantum gravity. Given the scope of their initiative, special interest is given to essays which address the following questions:
- Does quantum gravity eliminate spacetime as fundamental structure?
- How does quantum gravity explain the appearance of spacetime?
- What are the broader implications of quantum gravity or of the emergence of spacetime for metaphysical (and other) accounts of the world?
The overarching goal of hosting the competition is to stimulate new interdisciplinary work not only in the fields of quantum gravity, but also to engage philosophers (and philosophies) that are normally considered outside the realm of research.
Spacetime and Physical Equivalence by De Haro
De Haro’s essay, titled Spacetime and Physical Equivalence, lays out a conceptual scheme for assessing when two scientific theories amount to, generally speaking, ‘the same theory’ and when two theories describe ‘the same physical reality’. Only relatively recently have convincing examples of theories been produced which look very different (two theories which seem to be about two different subject matters), yet are equivalent in what they say about the world.
One such example is the equivalence (postulated in string theory) between describing the world in terms of a theory of gravitation versus in terms of a theory of quantum mechanics ‘living in one lower dimension’. This equivalence goes under the name of the holographic principle because it states that—as in the case of a hologram—there are two possible perspectives on the world: a four-dimensional perspective which incorporates gravity, and a three-dimensional perspective which does not include gravity. According to De Haro, the two perspectives may look entirely different, but are in fact completely equivalent.
The conceptual scheme described in the essay includes an account of what a scientific theory is and of its interpretation-- together with an account of the equivalence between theories and of the equivalence between the physics as described by theories.
De Haro then discusses some consequences of this account for theories of quantum gravity (for example, theories that purport to integrate quantum mechanics with Einstein’s theory of gravitation). In De Haro’s view, many of the notions (such as the dimensionality and the symmetries of spacetime) which are part and parcel of the description of gravity, are not necessarily part of what quantum gravity says about the world: they are only part of one of its multiple possible descriptions.
Publication and lecture in Chicago
For his contribution, De Haro will receive a monetary award in addition to an invitation to give a talk on his area of expertise at the University of Illinois at Chicago next year. His essay will also be published in one of two edited volumes the organisations are compiling via Oxford University Press.
The prize winning essays will also soon be available on the Beyond Spacetime website.