# Caustics of 1/rn binary gravitational lenses: from galactic haloes to exotic matter

@article{Bozza2015CausticsO1, title={Caustics of 1/rn binary gravitational lenses: from galactic haloes to exotic matter}, author={Valerio Bozza and Chiara Melchiorre}, journal={Journal of Cosmology and Astroparticle Physics}, year={2015}, volume={2016}, pages={040 - 040} }

We investigate the caustic topologies for binary gravitational lenses made up of two objects whose gravitational potential declines as 1/rn. With n<1 this corresponds to power-law dust distributions like the singular isothermal sphere. The n>1 regime can be obtained with some violations of the energy conditions, one famous example being the Ellis wormhole. Gravitational lensing provides a natural arena to distinguish and identify such exotic objects in our Universe. We find that there are still…

## 14 Citations

### Caustics in Gravitational Lensing by Mixed Binary Systems

- PhysicsUniverse
- 2020

We investigated binary lenses with 1/rn potentials in the asymmetric case with two lenses with different indexes n and m. These kinds of potentials have been widely used in several contexts, ranging…

### Dual-component plasma lens models

- PhysicsMonthly Notices of the Royal Astronomical Society
- 2019

In contrast to the converging, achromatic behaviour of axisymmetric gravitational lenses, diverging frequency-dependent lensing occurs from refraction due to a distribution of over-dense axisymmetric…

### Gravitational lensing by exotic objects

- Physics
- 2017

This paper reviews a phenomenological approach to the gravitational lensing by exotic objects such as the Ellis wormhole lens, where exotic lens objects may follow a non-standard form of the equation…

### Gravitational lensing by two photon spheres in a black-bounce spacetime in strong deflection limits

- PhysicsPhysical Review D
- 2021

We investigate gravitational lensing by a primary photon sphere which is formed by unstable circular light orbits, and by a secondary photon sphere on a wormhole throat in a black-bounce spacetime…

### Extended source effect on microlensing light curves by an Ellis wormhole

- Physics, Geology
- 2017

We can survey an Ellis wormhole which is the simplest Morris-Thorne wormhole in our Galaxy with microlensing. The light curve of a point source microlensed by the Ellis wormhole shows approximately…

### Gravitational lensing by black holes and their alternatives

- Physics
- 2017

Black holes have the ability to generate infinite number of images of any given source. These relativistic images are formed by light rays winding around the black hole several times. The…

### Strong gravitational lensing—a probe for extra dimensions and Kalb-Ramond field

- Physics
- 2016

Strong field gravitational lensing in the context of both higher spacetime dimensions and in presence of Kalb-Ramond field have been studied. After developing proper analytical tools to analyze the…

### Light curves of light rays passing through a wormhole

- Physics, Geology
- 2017

Gravitational lensing is a good probe into the topological structure of dark gravitating celestial objects. In this paper, we investigate the light curve of a light ray that passes through the throat…

### Deflection angle in the strong deflection limit in a general asymptotically flat, static, spherically symmetric spacetime

- Physics
- 2017

Gravitational lensing by the light sphere of compact objects like black holes and wormholes will give us information on the compact objects. In this paper, we provide an improved strong deflection…

### Gravitational lensing in the Simpson-Visser black-bounce spacetime in a strong deflection limit

- Physics
- 2021

A Simpson-Visser spacetime has two non-negative parameters $a$ and $m$ and its metric is correspond with (i) a Schwarzschild metric for $a=0$ and $m\ensuremath{\ne}0$, (ii) a regular black hole…

## References

SHOWING 1-10 OF 98 REFERENCES

### Demagnifying gravitational lenses toward hunting a clue of exotic matter and energy

- Physics
- 2013

We examine a gravitational lens model inspired by modified gravity theories and exotic matter and energy. We study an asymptotically flat, static, and spherically symmetric spacetime that is modified…

### An Atlas of Predicted Exotic Gravitational Lenses

- Physics
- 2009

Wide-field optical imaging surveys will contain tens of thou sands of new strong gravitational lenses. Some of these will have new and unusual image configurations, and so will enable new…

### Strong Lensing by Binary Galaxies

- Physics
- 2008

We study the problem of gravitational lensing by binary gala xies, idealized as two isothermal spheres. In a wide binary, each galaxy possesses individual tangential, nearly astroidal, caustics and…

### Lensing by binary galaxies modelled as isothermal spheres

- Physics
- 2008

We consider the problem of lensing by binary galaxies idealized as two isothermal spheres. This is a natural extension of the problem of lensing by binary point masses first studied by Schneider &…

### The binary gravitational lens and its extreme cases

- Physics
- 1999

The transition of the binary gravitational lens from the equal mass case to small (planetary) mass ratios q is studied. It is shown how the Limit of a (pure shear) Chang-Refsdal lens is approached,…

### Gravitational lensing shear by an exotic lens object with negative convergence or negative mass

- Physics
- 2013

Gravitational lens models with negative convergence (surface mass density projected onto the lens plane) inspired by modified gravity theories, exotic matter and energy have been recently discussed…

### Alternatives to Schwarzschild in the weak field limit of General Relativity

- Physics
- 2015

The metric outside an isolated object made up of ordinary matter is bound to be the classical Schwarzschild vacuum solution of General Relativity. Nevertheless, some solutions are known (e.g.…

### Gravitational lensing in Tangherlini spacetime in the weak gravitational field and the strong gravitational field

- Physics
- 2014

The gravitational lensing effects in the weak gravitational field by exotic lenses have been investigated intensively to find nonluminous exotic objects. Gravitational lensing based on 1 / r n…

### Properties of Planetary Caustics in Gravitational Microlensing

- Physics, Geology
- 2006

Although some of the properties of the caustics in planetary microlensing have been known, our understanding of them is mostly from scattered information based on numerical approaches. In this paper,…

### Cosmology with cosmic shear observations: a review

- PhysicsReports on progress in physics. Physical Society
- 2015

An outlook on the various future surveys and missions, for which cosmic shear is one of the main science drivers, and discuss promising new weak cosmological lensing techniques for future observations are discussed.