Final answer:
Gravitational lensing causes phenomena such as Einstein rings, multiple images, and magnification, supporting the theory of general relativity and helping to map dark matter distributions.
Step-by-step explanation:
Phenomena caused by gravitational lensing include Einstein rings, multiple images, and magnification of distant objects. Gravitational lensing occurs when the mass of an object, such as a galaxy, bends the fabric of spacetime, and causes the light from distant galaxies to be bent, creating multiple images or rings. These effects serve as evidence that supports the theory of general relativity and allow astronomers to detect otherwise invisible matter, such as dark matter, by observing the lensing effects it has on light from distant galaxies.
The observation of multiple images with identical red shifts, as seen in the provided figures, indicates that they are of the same object, and not affected by the distinct paths through space. This also suggests that red shifts are intrinsic to the galaxies and not a result of light 'getting tired' through its journey in space. Studies of galaxy clusters exhibiting gravitational lensing can be used to produce detailed maps of mass distribution and confirm the presence of much more dark matter relative to luminous matter.