Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A long EF-equivalence non isomorphic models   There has been much interest on constructing models which are not isomorphic
of cardinality lambda but are equivalent under the Ehrenfeucht-Fraisse game of
length alpha even for every alpha<lambda. So under G.C.H. we know much. We deal
here with constructions of such pairs of models proven in ZFC and get the
existence under mild conditions.

17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
22
The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
15
The categories of this paper are: nucl-ex
16
The categories of this paper are: stat