Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Imaging a boson star at the Galactic center   Millimeter very long baseline interferometry will soon produce accurate
images of the closest surroundings of the supermassive compact object at the
center of the Galaxy, Sgr A*. These images may reveal the existence of a
central faint region, the so-called shadow, which is often interpreted as the
observable consequence of the event horizon of a black hole. In this paper, we
compute images of an accretion torus around Sgr A* assuming this compact object
is a boson star, i.e. an alternative to black holes within general relativity,
with no event horizon and no hard surface. We show that very relativistic
rotating boson stars produce images extremely similar to Kerr black holes,
showing in particular shadow-like and photon-ring-like structures. This result
highlights the extreme difficulty of unambiguously telling the existence of an
event horizon from strong-field images.

15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
32
The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
3
The categories of this paper are: physics
36
The categories of this paper are: cmp-lg
22
The categories of this paper are: chao-dyn
4
The categories of this paper are: cond-mat
20
The categories of this paper are: acc-phys
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph