Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Exploring extra dimensions with scalar waves   This paper provides a pedagogical introduction to the physics of extra
dimensions focussing on the ADD, Randall-Sundrum and DGP models. In each of
these models, the familiar particles and fields of the standard model are
assumed to be confined to a four dimensional space-time called the brane; the
brane is a slice through a higher dimensional space-time called the bulk. The
geometry of the ADD, Randall-Sundrum and DGP space-times is described and the
relation between Randall-Sundrum and Anti-de-Sitter space-time is explained.
The necessary differential geometry background is introduced in an appendix
that presumes no greater mathematical preparation than multivariable calculus.
The ordinary wave equation and the Klein-Gordon equation are briefly reviewed
followed by an analysis of the propagation of scalar waves in the bulk in all
three extra-dimensional models. We also calculate the scalar field produced by
a static point source located on the brane for all three models. For the ADD
and Randall-Sundrum models at large distances the field looks like that of a
point source in four space-time dimensions but at short distances it crosses
over to a form appropriate to the higher dimensional space-time. For the DGP
model the field has the higher dimensional form at long distances rather than
short. The scalar field results provide qualitative insights into the
corresponding behavior of gravitational fields. In particular the explanation
within the ADD and Randall-Sundrum model of the weakness of gravity compared to
other forces is discussed as are the implications of the two models for
colliders and other experiments.

31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
17
The categories of this paper are: q-fin
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
29
The categories of this paper are: funct-an
2
The categories of this paper are: math