Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Glimmers of a pre-geometric perspective   Space-time measurements and gravitational experiments are made by using
objects, matter fields or particles and their mutual relationships. As a
consequence, any operationally meaningful assertion about space-time is in fact
an assertion about the degrees of freedom of the matter (\emph{i.e} non
gravitational) fields; those, say for definiteness, of the Standard Model of
particle physics. As for any quantum theory, the dynamics of the matter fields
can be described in terms of a unitary evolution of a state vector in a Hilbert
space. By writing the Hilbert space as a generic tensor product of "subsystems"
we analyse the evolution of a state vector on an information theoretical basis
and attempt to recover the usual space-time relations from the information
exchanges between these subsystems. We consider generic interacting second
quantized models with a finite number of fermionic degrees of freedom and
characterize on physical grounds the tensor product structure associated with
the class of "localized systems" and therefore with "position". We find that in
the case of free theories no space-time relation is operationally definable. On
the contrary, by applying the same procedure to the simple interacting model of
a one-dimensional Heisenberg spin chain we recover the tensor product structure
usually associated with "position". Finally, we discuss the possible role of
gravity in this framework.

34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
24
The categories of this paper are: dg-ga
29
The categories of this paper are: funct-an
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg