Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Sigma-model soliton intersections from exceptional calibrations   A first-order `BPS' equation is obtained for 1/8 supersymmetric intersections
of soliton-membranes (lumps) of supersymmetric (4+1)-dimensional massless sigma
models, and a special non-singular solution is found that preserves 1/4
supersymmetry. For 4-dimensional hyper-K\"ahler target spaces ($HK_4$) the BPS
equation is shown to be the low-energy limit of the equation for a
Cayley-calibrated 4-surface in $\bE^4\times HK_4$. Similar first-order
equations are found for stationary intersections of Q-lump-membranes of the
massive sigma model, but now generic solutions preserve either 1/8
supersymmetry or no supersymmetry, depending on the time orientation.

26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
30
The categories of this paper are: q-alg
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
19
The categories of this paper are: eess
29
The categories of this paper are: funct-an
22
The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom