Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Synthetic Dimension in Photonics   The physics of a photonic structure is commonly described in terms of its
apparent geometric dimensionality. On the other hand, with the concept of
synthetic dimension, it is in fact possible to explore physics in a space with
a dimensionality that is higher as compared to the apparent geometrical
dimensionality of the structures. In this review, we discuss the basic concepts
of synthetic dimension in photonics, and highlighting the various approaches
towards demonstrating such synthetic dimension for fundamental physics and
potential applications.

23
The categories of this paper are: solv-int
33
The categories of this paper are: plasm-ph
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
31
The categories of this paper are: ao-sci
14
The categories of this paper are: math-ph
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: astro-ph
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The categories of this paper are: math
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The categories of this paper are: eess
5
The categories of this paper are: gr-qc
10
The categories of this paper are: q-bio
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The categories of this paper are: econ