FQXi
A panel discussion at FQXi’s 5th International Conference with James Hartle, Adrian Kent, Susanne Still, David Wolpert, David Wallace, Alan Guth, and Adam Brown.
Source
What is an Observer? A Panel with James Hartle, Susanne Still, David Wallace, and Alan Guth
The measure problem strikes me as odd. You don't need to measure probabilities for the entire universe/multiverse throughout all time. If you select a finite inflationary patch at a specific time that you define as t=0, you can take a finite measure of the space that patch has expanded into within a finite time. As you expand that time forward, I imagine that most measures would approach specific values depending on specific parameters selected as t increases (in other words, there's a limit as t approaches infinity). This doesn't mean that you have a measure at infinity, but it does mean that you can make a prediction for any finite region, continuous region in a finite, continuous timeframe. Do you actually need more than that?
its really funny that a bunch of bonified, smart, paid observers struggle to define their very nature. Unless they want an alien life form to some day treat them as if their experience is not real, they should start to consider this not so philosophical question.
in order to define observation you must be able to observe observation, as both a 3rd person and a 1st person experience. I wonder if its possible to Fully observe observation and if so, what context could possible sum it up?
noncommutatve phase is the observer