Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: What is in a pebble shape?   We propose to characterize the shapes of flat pebbles in terms of the
statistical distribution of curvatures measured along the pebble contour. This
is demonstrated for the erosion of clay pebbles in a controlled laboratory
apparatus. Photographs at various stages of erosion are analyzed, and compared
with two models. We find that the curvature distribution complements the usual
measurement of aspect ratio, and connects naturally to erosion processes that
are typically faster at protruding regions of high curvature.

12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
30
The categories of this paper are: q-alg
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
10
The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga