- #1
Heidi
- 418
- 40
Hi Pfs
Partial tracing maps what occurs in a big Hilbert space toward a smaller one. We have to use it when degrees of freedom are physically unobservable or when we have only a coarse grained view of the environment. it is like in Flatland , where the two dimensional inhabitants has no access to the third dimension. non they only see the shadows of what is above. for them non parallel lines always have an intersection point even if this point does not exist above them. They see this point !
Are there also for us things that we see and measure which are like these intersection points ( due to partial tracing)?
Partial tracing maps what occurs in a big Hilbert space toward a smaller one. We have to use it when degrees of freedom are physically unobservable or when we have only a coarse grained view of the environment. it is like in Flatland , where the two dimensional inhabitants has no access to the third dimension. non they only see the shadows of what is above. for them non parallel lines always have an intersection point even if this point does not exist above them. They see this point !
Are there also for us things that we see and measure which are like these intersection points ( due to partial tracing)?