209 citations · 646 across the 17 of their papers we have counts for
24 papers
An observational signature for extremal black holes
Stefanos Aretakis, Gaurav Khanna, Subir Sabharwal
We consider scalar perturbations of the Reissner--Nordström family and the Kerr family. We derive a characteristic expression of the radiation field, at any given unit solid angle…
Characteristic gluing to the Kerr family and application to spacelike gluing
Stefanos Aretakis, Stefan Czimek, Igor Rodnianski
This is the third paper in a series of papers adressing the characteristic gluing problem for the Einstein vacuum equations. We provide full details of our characteristic gluing (i…
The characteristic gluing problem for the Einstein vacuum equations. Linear and non-linear analysis
Stefanos Aretakis, Stefan Czimek, Igor Rodnianski
This is the second paper in a series of papers adressing the characteristic gluing problem for the Einstein vacuum equations. We solve the codimension- characteristic gluing pr…
The characteristic gluing problem for the Einstein equations and applications
Stefanos Aretakis, Stefan Czimek, Igor Rodnianski
In this paper we introduce the characteristic gluing problem for the Einstein vacuum equations. We present a codimension- gluing construction for characteristic initial data wh…
Price's law and precise late-time asymptotics for subextremal Reissner-Nordström black holes
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
In this paper, we prove precise late-time asymptotics for solutions to the wave equation supported on angular frequencies greater or equal to on the domain of outer communic…
Late-time tails and mode coupling of linear waves on Kerr spacetimes
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We provide a rigorous derivation of the precise late-time asymptotics for solutions to the scalar wave equation on subextremal Kerr backgrounds, including the asymptotics for proje…
A non-degenerate scattering theory for the wave equation on extremal Reissner-Nordstrom
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
It is known that sub-extremal black hole backgrounds do not admit a (bijective) non-degenerate scattering theory in the exterior region due to the fact that the redshift effect at…
Nonlinear scalar perturbations of extremal Reissner-Nordström spacetimes
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We present the first rigorous study of nonlinear wave equations on extremal black hole spacetimes without any symmetry assumptions on the solution. Specifically, we prove global ex…
Horizon hair of extremal black holes and measurements at null infinity
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
It is shown that the conserved charges on the event horizon and the Cauchy horizon associated to scalar perturbations on extremal black holes are externally measurable from null in…
Late-time asymptotics for the wave equation on extremal Reissner-Nordström backgrounds
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We derive the precise late-time asymptotics for solutions to the wave equation on extremal Reissner-Nordström black holes and explicitly express the leading-order coefficients in t…
Logarithmic corrections in the asymptotic expansion for the radiation field along null infinity
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We obtain the second-order asymptotics for the radiation field of spherically symmetric solutions to the wave equation on spherically symmetric and asymptotically flat backgrounds…
Late-time asymptotics for the wave equation on spherically symmetric, stationary spacetimes
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We derive precise late-time asymptotics for solutions to the wave equation on spherically symmetric, stationary and asymptotically flat spacetimes including as special cases the Sc…
A vector field approach to almost-sharp decay for the wave equation on spherically symmetric, stationary spacetimes
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We present a new vector field approach to almost-sharp decay for the wave equation on spherically symmetric, stationary and asymptotically flat spacetimes. Specifically, we derive…
Asymptotic blow-up for a class of semilinear wave equations on extremal Reissner-Nordström spacetimes
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We prove small data global existence for a class of semilinear wave equations satisfying the null condition on extremal Reissner-Nordstrom black hole backgrounds with nonlinear ter…
The trapping effect on degenerate horizons
Yannis Angelopoulos, Stefanos Aretakis, Dejan Gajic
We show that degenerate horizons exhibit a new trapping effect. Specifically, we obtain a non-degenerate Morawetz estimate for the wave equation in the domain of outer communicatio…
The characteristic gluing problem and conservation laws for the wave equation on null hypersurfaces
Stefanos Aretakis
We obtain necessary and sufficient conditions for the existence of "conservation laws" on null hypersurfaces for the wave equation on general four-dimensional Lorentzian manifolds.…
On a foliation-covariant elliptic operator on null hypersurfaces
Stefanos Aretakis
We introduce a new elliptic operator on null hypersurfaces of four-dimensional Lorentzian manifolds. This operator depends on the first and second fundamental forms of the sections…
Nonlinear instability of scalar fields on extremal black holes
Stefanos Aretakis
We prove a new type of finite time blow-up for a class of semilinear wave equations on extremal black holes. The initial data can be taken to be arbitrarily close to the trivial da…
A note on instabilities of extremal black holes under scalar perturbations from afar
Stefanos Aretakis
In previous work of the author it was shown that instabilities of solutions to the wave equation develop asymptotically along the event horizon of extremal Kerr provided a certain…
Horizon Instability of Extremal Black Holes
Stefanos Aretakis
We show that axisymmetric extremal horizons are unstable under linear scalar perturbations. Specifically, we show that translation invariant derivatives of generic solutions to the…
Stability and Instability of Extreme Reissner-Nordström Black Hole Spacetimes for Linear Scalar Perturbations II
Stefanos Aretakis
This paper contains the second part of a two-part series on the stability and instability of extreme Reissner-Nordstrom spacetimes for linear scalar perturbations. We continue our…
Stability and Instability of Extreme Reissner-Nordström Black Hole Spacetimes for Linear Scalar Perturbations I
Stefanos Aretakis
We study the problem of stability and instability of extreme Reissner-Nordstrom spacetimes for linear scalar perturbations. Specifically, we consider solutions to the linear wave e…
Decay of Axisymmetric Solutions of the Wave Equation on Extreme Kerr Backgrounds
Stefanos Aretakis
We study the Cauchy problem for the wave equation on extreme Kerr backgrounds under axisymmetry. Specifically, we consider regular axisymmetric initial data prescribed on a Cauchy…
The Wave Equation on Extreme Reissner-Nordström Black Hole Spacetimes: Stability and Instability Results
Stefanos Aretakis
We consider solutions to the linear wave equation on a suitable globally hyperbolic subset of an extreme Reissner-Nordstrom spacetime, arising from regular initial data prescribed…