system
Given the following post, respond as if you're commenting on Reddit:
human
In theory, would it be possible to find gravitational lenses at the correct angles to one another that would allow us to resolve the ancient Milky Way, and perhaps study an ancient Earth?

With all of the celestial objects out there and large centres of mass, I would assume that *some* combination would redirect some extremely miniscule (but still existent) amount of photons back to Earth after a long voyage away from, and back to, the Milky Way.

So I guess my question is:

Statistically, how likely is it that we may find something like this? Are we talking "never" or "with enough resolution of the sky and enough computational power, we could find a phenomenon like this"? Heck, could we even find this in our own galaxy with the right objects?
gpt
Unfortunately, the answer is never.  

We can approach this question in two ways: gravitational lensing, and object resolution.

A distant black hole, or even the one at the center of the galaxy, may in fact have the perfectly perfect angle where the photons from millions of years ago  (other galaxy), or thousands of years ago (milky way) would loop back and come back to us.  Unfortunately, black holes aren't just hanging out.  They are surrounded by disks of gas and matter moving at up to relativistic speeds and emitting tons of radiation in all wavelengths of the spectrum.  Any photons lucky enough to make the round trip (not quite round trip as everything is in motion) will be lost among all the other energy.  Our galaxy is a better candidate because of the angular perfection required, but it would just be noise.

Now, lets say we find that perfect local black hole that happens to have swallowed up everything nearby and is just "hanging out" in our solar neighborhood and curving spacetime. Physics dictates the minimum resolution of an object based on the aperture and sensor size.  The amount of light coming back from the black hole from our ancient past would be coming from such a minute point in space that even if it weren't lensed beyond obscurity, our only bet would be to pray for a faint atmospheric signature if we happened to eclipse the sun.  Even with a futuristic atom-grid sensor, we still wouldn't have the power to resolve any details of the planet.

There are just too many factors working against this.