Physics Stack Exchange
Physics Stack Exchange

Questions tagged [gravitational-lensing]

Gravitational lensing occurs when light from a distant object is bent as it travels to an observer, due to passing through the gravitational field of a massive object (such as a galaxy, or black hole).

Gravitational lensing occurs when light from a distant object is bent as it travels to an observer, due to passing through the gravitational field of a massive object (such as a galaxy, or black hole).

Spacetime around a massive object (such as a galaxy cluster or a black hole) is curved, and as a result light rays from a background source (such as a galaxy) propagating through spacetime are bent. The lensing effect can magnify and distort the image of the background source.

Simulated gravitational lensing

197 questions
2
votes
1 answer

How does an object such as a galaxy split the image from a more distant galaxy into two images?

I was reading a recent discussion on gravitational lensing, in which it described the bending of light from a distant galaxy as it passed a nearer galaxy to produce two images of the same distant galaxy. How does that happen? If the distant object…
Anthony X
  • 4,084
1
vote
1 answer

Observed Effects of Gravitational Lensing 2

So what is the minimum amount of mass that is required for the gravitational lensing effect to be visible? For instance, we can not observe the suns light during a solar eclipse because the moon does not have enough mass to curve space sufficiently…
Brando
  • 649
0
votes
1 answer

Axially Symmetric Lens Integration

I'm trying to understand the deflection of light due to an axially symmetric gravitational lens following chapter 2.3 of these Heidelberg lecture notes. In doing so, I encounter the integral (2.12 a) $$\int_0^{2\pi} \frac{r - r'\cos(\phi)}{r^2 +…
GrassyNol
  • 364
0
votes
1 answer

Travel/peek back in time with gravitational lensing?

I wonder if it would be possible to peek directly in our past-self by using gravitational lensing in such a way where we could (would be able to) calculate/triangulate the exact path and point a very powerful telescope in this very specific…
xray0
  • 510
0
votes
1 answer

Convergence and shear in weak gravitational lensing

When we try to reconstruct the surface mass density distribution of a lens, we can do the following: Divide the picture into a grid, and for each "pixel" assign an effective distortion by finding $g$ (the distortion, or "reduced shear") that…
Yoni
  • 735
0
votes
3 answers

Observed Effects of Gravitational Lensing?

If Gravitational lensing is real why cant we see the sun during a solar eclipse? Why doesn't the suns light follow the curve of space created by the moon and become visible to us?
Brando
  • 649
0
votes
2 answers

Observing the past

Suppose that we have a massive stellar object in space, so massive that it can cause significant lensing. It is also theoretically possible to turn light by 180 degrees (u-turn).So, assuming this body is x light years away, suppose we oberve it, and…
Lelouch
  • 3,616
0
votes
1 answer

Is "gravitational lensing" due to momentum or curvature of space?

I'm confused about how massless particle is influenced by gravitational force. Some source point to the energy conversion to mass and vice versa so light is treated similarly, other source mentioned "space tells light how to move" eliminating the…
user6760
  • 12,980
0
votes
2 answers

How much $G$ is required to bend light?

How much $G$ is required to bend light?. Also, please explain what happens if a powerful light beam in a vacuum is intercepted by electromagnetic fields on either sides.
Shiva
  • 11