Large Grants
    - Introduction
    - Awardees
    - Introduction
    - Winners
Previous Programs

2016 Physics of the Observer
2016 Awardees

2015 The Physics of What Happens
2015 Awardees

2013 Physics of Information
2013 Awardees

2010 The Nature of Time
2010 Awardees

2008 Foundational Questions in Physics and Cosmology
2008 Awardees

2006 Foundational Questions in Physics and Cosmology
2006 Awardees

Kevin Resch
University of Waterloo

Robert Spekkens
Perimeter Institute for Theoretical Physics

Project Title

Experimental test of intrinsically quantum causal relations

Project Summary

If two variables are found to be statistically correlated, there are many different causal mechanisms that could explain this. It could be that one variable causally influences the other. Or, they could both be effects of a common cause. Or perhaps, with some probability, it is a cause-effect relation, and with some probability, it is a common-cause relation. Alternatively, there may be a cause-effect mechanism and a common-cause mechanism acting simultaneously. In a quantum world, the menu of possibilities for how two systems are causally related is broader still: it could be that there is a quantum coherent mixture of cause-effect and common-cause mechanisms. We propose a theoretical investigation of the circumstances under which such novel nonclassical causal structures can arise and how their presence can be detected, as well as an experiment using single photons that realizes and detects such a structure. Understanding the nature of causation in a quantum world is anticipated to shed light on foundational problems in quantum theory, such as Bell's theorem, as well as problems in quantum gravity, where space and time must be given a quantum description.

Back to List of Awardees  
Please enter your e-mail address:

And select the letter between 'S' and 'U':

Note: Joining the FQXi mailing list does not give you a login account or constitute membership in the organization.