Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Undecidability and the problem of outcomes in quantum measurements   We argue that it is fundamentally impossible to recover information about
quantum superpositions when a system has interacted with a sufficiently large
number of degrees of freedom of the environment. This is due to the fact that
gravity imposes fundamental limitations on how accurate measurements can be.
This leads to the notion of undecidability: there is no way to tell, due to
fundamental limitations, if a quantum system evolved unitarily or suffered
wavefunction collapse. This in turn provides a solution to the problem of
outcomes in quantum measurement by providing a sharp criterion for defining
when an event has taken place. We analyze in detail in examples two situations
in which in principle one could recover information about quantum coherence: a)
"revivals" of coherence in the interaction of a system with the environment and
b) the measurement of global observables of the system plus apparatus plus
environment. We show in the examples that the fundamental limitations due to
gravity and quantum mechanics in measurement prevent both revivals from
occurring and the measurement of global observables. It can therefore be argued
that the emerging picture provides a complete resolution to the measurement
problem in quantum mechanics.

26
The categories of this paper are: bayes-an
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
35
The categories of this paper are: mtrl-th
31
The categories of this paper are: ao-sci
11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
12
The categories of this paper are: nucl-th
18
The categories of this paper are: econ