Causality in quantum theory and beyond: towards a theory of quantum gravity
APA
Hardy, L. (2006). Causality in quantum theory and beyond: towards a theory of quantum gravity. Perimeter Institute. https://pirsa.org/06070045
MLA
Hardy, Lucien. Causality in quantum theory and beyond: towards a theory of quantum gravity. Perimeter Institute, Jul. 19, 2006, https://pirsa.org/06070045
BibTex
@misc{ pirsa_PIRSA:06070045, doi = {10.48660/06070045}, url = {https://pirsa.org/06070045}, author = {Hardy, Lucien}, keywords = {}, language = {en}, title = {Causality in quantum theory and beyond: towards a theory of quantum gravity}, publisher = {Perimeter Institute}, year = {2006}, month = {jul}, note = {PIRSA:06070045 see, \url{https://pirsa.org}} }
Perimeter Institute for Theoretical Physics
Talk Type
Abstract
The way we combine operators in quantum theory depends on the causal relationship involved. For spacelike separated spacetime regions we use the tensor product. For immediately sequential regions of spacetime we use the direct product. In the latter case we lose information that is we cannot go from the direct product of two operators to the two original operators. This is a kind of compression. We will see that such compression is associated with causal adjacency. We will situate this in the context of a much broader framework potentially suitable for developing a theory of quantum gravity.