Wavefn collapse via informationalism. These 3 eqn. model the collapse. Here's how:
(The full references are here.)
First, Shrodinger saw that observations are discrete. Likewise the informationalism of Jon Barwise assumes that "information comes in pieces." Therefore the problem of the continuum (cf. John Baez, Struggles with the continuum.) is not in play. Here I assume that a discrete observation produces a piece of information.
For example, when in the two slit experiment an electron hits the plate, a piece of information is produced.
[math]theSituation \models information:available[/math]
Next I apply is the basic tenet of Barwise's informationalism:
"The Inverse Relationship Principle: Whenever there is an increase in available information there is a corresponding decrease in possibilities, and vice versa."
Given all the possible locations of the electron on the plate, the electron is observed in only one location. And this makes a piece of information available.
The inverse relationship principle then tells me that because of this increase in information, "there is a corresponding decrease in possibilities."
In other words, as soon as the information becomes available that the electron hit the plate at location, say, "j", no other possible location, say, "i not equal to j" is now possible.
[math]theSituation \models possibility_i:impossible[/math]
Using natural language, "the wave function has collapsed." Or more formally--
[math]theSituation \models \Psi_i=0[/math]
