Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Bundles with a lift of infinitesimal diffeomorphisms   We slightly extend the notion of a natural fibre bundle by requiring
diffeomorphisms of the base to lift to automorphisms of the bundle only
infinitesimally, i.e. at the level of the Lie algebra of vector fields. Spin
structures are natural only in this extended sense. We classify fibre bundles
with this property, assuming a finite dimensional structure group. This
includes all spin structures, but only some generalised spin structures. This
classification links the gauge group G to the topology of space-time.

31
The categories of this paper are: ao-sci
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
29
The categories of this paper are: funct-an
9
The categories of this paper are: nlin
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org