Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Contractible Extremal Rays on \overline{M}_{0,n}   We consider the cones of curves and divisors on the moduli space of stable
pointed rational curves,M_n, and on the quotient by the symmetric group, Q_n,
which is a moduli space of pairs. We find generators for contractible extremal
rays of the cone of curves NE_1(M_n), and for the cone of divisors NE^1(Q_n).
This second cone turns out to be simplicial. We give complete descriptions of
NE_1(M_n) and NE_1(Q_n) for small n (< 8 in the first case, < 11 in the
second). We also have results of independent interest on when curves in a
divisor generate the cone of curves of the ambient variety.

35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
0
The categories of this paper are: hep-ph
17
The categories of this paper are: q-fin
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
24
The categories of this paper are: dg-ga
5
The categories of this paper are: gr-qc
8
The categories of this paper are: hep-ex
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The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
18
The categories of this paper are: econ
26
The categories of this paper are: bayes-an