89 research outputs found
Solitonic Excitations in AdS2
We construct large families of supergravity solutions that are asymptotic to
AdS and terminate with a cap that is singular in two dimensions but smooth
in higher dimensions. These solutions break supersymmetry and conformal
invariance. They correspond to finite-energy excitations in empty AdS that
back-react on the geometry by inducing non-trivial bubbling topology. They are
constructed from the novel technique associated with the Ernst formalism for
AdS solitons in supergravity [arXiv:2210.06483]. The
technique is applied to in M-theory with T.
The directions of degenerate smoothly as a chain of bolts which
ends the spacetime in the IR and generates non-supersymmetric bubbles supported
by M2-brane flux. Some specific solutions have "flat" directions where the
sizes of their bubbles are totally unconstrained and can be arbitrarily tuned
while the asymptotics remains fixed. The solitons should correspond to regular
non-supersymmetric states of a holographically dual CFT.Comment: 46 pages, 15 figures, 3 appendices. arXiv admin note: text overlap
with arXiv:2210.0648
Topological Stars, Black holes and Generalized Charged Weyl Solutions
We construct smooth static bubble solutions, denoted as topological stars, in
five-dimensional Einstein-Maxwell theories which are asymptotic to
S. The bubbles are supported by allowing
electromagnetic fluxes to wrap smooth topological cycles. The solutions live in
the same regime as non-extremal static charged black strings, that reduce to
black holes in four dimensions. We generalize to multi-body configurations on a
line by constructing closed-form generalized charged Weyl solutions in the same
theory. Generic solutions consist of topological stars and black strings
stacked on a line, that are wrapped by electromagnetic fluxes. We embed the
solutions in type IIB String Theory on ST. In this framework, the
charged Weyl solutions provide a novel class in String Theory of multiple
charged objects in the non-supersymmetric and non-extremal black hole regime.Comment: 39 pages + Appendices, minor changes and typos correcte
Electromagnetic Entrapment in Gravity
We derive specific properties of electromagnetism when gravitational effects
are not negligible and analyze their impact on new physics at the horizons of
black holes. We show that a neutral configuration of charges in a region of
high redshift, characterized by a large , produces a highly localized
electromagnetic field that vanishes just beyond that region. This phenomenon
implies the existence of extensive families of spacetime structures generated
by electromagnetic degrees of freedom that are as compact as black holes. We
construct neutral bound states of extremal black holes in four dimensions and
in five dimensions, where one direction is compact. These geometries are
indistinguishable from a neutral black hole, referred to as distorted
Schwarzschild, except in an infinitesimal region near its horizon where the
entrapped electromagnetic structures start to manifest. The five-dimensional
solutions satisfy various criteria for describing black hole microstructure:
they increase in size with the Newton constant, are as compact as the
Schwarzschild black hole, and have an entropy that scales like .Comment: 37 pages + Appendix, 14 figure
The Uplifton
Almost all proposals to construct de Sitter vacua with a small cosmological
constant involve flux compactifications with stabilized moduli. These give AdS
vacua, which are uplifted to de Sitter by adding antibranes in certain regions
of the compactification manifold. However, antibranes are charged, singular and
interact nontrivially with other ingredients of the compactification; this can
invalidate the de Sitter construction. In this Letter, we construct a new
ingredient for uplifting AdS solutions to de Sitter, which is neutral, smooth
and horizonless, and therefore bypasses some of the problems of antibrane
uplift.Comment: 5 pages, 1 figur
Imaging Topological Solitons: the Microstructure Behind the Shadow
We study photon geodesics in topological solitons that have the same
asymptotic properties as Schwarzschild black holes. These are coherent states
in string theory corresponding to pure deformations of spacetime through the
dynamics of compact extra dimensions. We compare these solutions with
Schwarzschild black holes by computing null geodesics, deriving Lyapunov
exponents, and imaging their geometries as seen by a distant observer. We show
that topological solitons are remarkably similar to black holes in apparent
size and scattering properties, while being smooth and horizonless. Incoming
photons experience very high redshift, inducing phenomenological horizon-like
behaviors from the point of view of photon scattering. Thus, they provide a
compelling case for real-world gravitational solitons and topological
alternatives to black holes from string theory.Comment: 15 pages and 6 figures, v2: typos corrected, v3: minor changes and
published versio
Cavity effect in the quasinormal mode spectrum of topological stars
We study scalar perturbations of topological solitons, smooth horizonless
solutions in five-dimensional Einstein-Maxwell theory that correspond to
coherent states of gravity via the dynamics of extra compact dimensions. First,
we compute scalar quasinormal modes for topological stars that have a single
unstable photon sphere, and we show that the spectrum is very similar to that
of a black hole with the same photon sphere. Next, we study topological stars
that have both a stable inner photon sphere and an unstable one. The first few
quasinormal modes are localized around the inner photon sphere. The spectrum
also contains ''black-hole like modes'' localized at the unstable outer photon
sphere. The frequencies of these modes are similar to those of a black hole,
but their imaginary part is smaller due to a cavity effect associated with the
inner photon sphere. The longer damping produced by this trapping effect may
have implications for black hole spectroscopy.Comment: 17 pages + Appendix, 11 figure
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