A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
Rules
This is a science community. We use the Dawkins definition of meme.
But only after 10 years. You couldn't see anything that wasn't visible from the viewpoint of the mirror beforehand, as from earth's point of view the mirror isn't there yet. And if you're there anyway… you can just look at Earth with the craft that's on the position of the mirror already.
Also it would take at least 10 years to put a mirror there.
That's why we need to find a natural mirror somewhere already out there, so we can see into our past. Something like a planet made of pure mercury, or an arrangement of blackholes doing gravitational lensing that bends our light back to us, or whatever. We'd also need instruments vastly superior than what we currently have in order to get any useful information out of seeing our own light bounced back to us from so far away
... But still! the idea that it's at least hypothetically possible to actually see our own past is very exciting!
Just look in any mirror. What you see is also you in the past.
You don't even need a mirror, just look at your hands or feet or whatever, that's what your hand or foot or whatever looked like 2 or 3 nanoseconds ago.
“‘That’s a picture of me when I was younger.’ Yeah, no shit. Every picture of you is a picture of you when you were younger.”
-Mitch Hedberg
He didn't curse in that line. In fact he didn't curse much generally. I don't have any objection to curse words, it just doesn't sound like his voice when you add curse words in.
Fuck shit ass titties. I just had to get that out after talking about not cursing
Fuck shit ass tities right back at you.
I tried to point this out and everyone got grumpy. It must be nice being so attractive.
True true. Heck it takes some 100-150ms for your brain to register what your eyes have seen.
I'm assuming the inverse square law would hinder us from seeing anything useful. But now I'm imagining scientists being ecstatic about discovering a foreign signal, only to realise its us from the past
That's highly unlikely basically because of the inverse square law. Even tightly focused beams dissipate quite effectively over light-hours, let alone light years. We'd be lucky to catch a single photon from our past selves over any significant distance.
For reference, look up how weak the signal is even just coming back from the moon when people try to hit the retroreflectors with lasers. Or how crazy weak the signals are when they reach Voyager.
Hey, don't you bring logic in here!
Only after 20 years. Light will take 10y to make it from earth to the mirror, and 10y to travel back.
No, the light would be reflected as soon as the mirror is set up. If the mirror is set up 10 lightyears away it would take 10 years for you to see it and whatever it reflects. There already is light on the way to the position of the mirror before you set it up.
Oops, that's right!
None of these sound like deal breakers to this great idea
NASA: We’ve been getting a lot of footage of you being cringy in high school.
oh god oh fuck there's indestructible physical evidence of my Homestuck phase
Meh, amateurs. Being cringy as a kid at times is pretty much inevitable. That's when you learn your ways.
You can watch me being cringy as an adult for decades.
You can already do this with the light bent around black holes, it's just a bit hard to make out the image... make sure you wipe down your black hole with a damp cloth, you don't want a smudgey black hole
Instructions nuclear, toaster stuck in black hole
"Aw man... that's the third goddamned cloth I've dropped into this goddamned event horizon this week... and it's barely just Tuesday."
and if you look through the butt end of the telescope, you can see in the future
Isn't the butt end, the end you normally look through? I'd think the end facing the stars would be the front end.
It'd actually be cool as fuck if we could make some kind of Paycheck-style time machine that lets you see into the past by simply looking at light reflected off other celestial objects.
It could theoretically work looking backwards, but not forwards as it was used in the film. Of course, it'd have to have insane resolution for it to be like a video of what happened on the planet and not just a dot of light.
time machine that lets you see into the past by simply looking at light
You mean, this ?
lol
Real time, tho. That way we can see photographs from before cameras, too. Watch what dinosaurs were doing n stuff.
Unfortunately light wouldn't remain collimated over a 33 million light year distance which is what we would need to see dinosaurs
How about heat? Or some other radiation? 🤔
Alternatively, and slightly cheaper, put a satellite into orbit and just record everything on the ground it looks at, hang onto recordings for 10 years.
But that's boring, doing it with light is way better.
Also the governments already do that and don't want to share.
Wow that's what the movie was called. It's been on the back of my mind for years.
If you did this quickly with a warp drive or whatever, you would still need at least ten years to see the results, so you could only see as far back as when you put the mirror up at the most.
No, you can see 20 years into the past, but only in 10 years. If you managed to will it into existence now, the light that left us 10 years ago would arrive at the mirror now and start heading back. That light would hit earth 10 years from now, so in 2035 we'd be able to see 2015
You may need to squint a little.
Big brother called, you weren’t supposed to leak this hack.
If only they did work into the future then they could have stopped you from spilling the beans.
Yeah, but it'd take us strictly longer than N years to place a mirror N light years away form Earth, so kinda useless.
We just need to point our telescopes towards the phantom zone where Zod and his buddies can reflect the light back.
It would be neat to record the mirror as it was going.
Ignoring physics of moving a mirror near the SoL, having a recording of it would both be cool to watch and would help confirm on a macro level the effects of speed-related dilation.