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.
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!
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
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.
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.
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.
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
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.
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
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.
The mirror always looks back... (insert annoying spooky laugh)
But, just to be less of a Halloween spookster. The mirror is placed in a rather exotic location in space, and between the mirror and the Earth is... wait for it... youre going to hate this lol... a naturally occurring closed timelike curve! See, I told you youd hate it lol.
57 Comments
Natanox@discuss.tchncs.de · 90 pts · 315d
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.
Beacon@fedia.io · 46 pts · 315d
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!
Klear@quokk.au · 19 pts · 315d
Just look in any mirror. What you see is also you in the past.
homesweethomeMrL@lemmy.world · 24 pts · 315d
“‘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
Beacon@fedia.io · 19 pts · 315d
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
KurtVonnegut@mander.xyz · 4 pts · 315d
Fuck shit ass tities right back at you.
homesweethomeMrL@lemmy.world · 1 pts · 315d
He did on the record.
ameancow@lemmy.world · 3 pts · 315d
Sprawl@lemmy.world · 2 pts · 315d
True true. Heck it takes some 100-150ms for your brain to register what your eyes have seen.
Venat0r@lemmy.world · 1 pts · 313d
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.
SapphironZA@sh.itjust.works · 1 pts · 315d
So you are saying, I always looking younger in the mirror?
kernelle@lemmy.dbzer0.com · 7 pts · 315d
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
MotoAsh@piefed.social · 7 pts · 315d
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.
ameancow@lemmy.world · 0 pts · 315d
Beacon@fedia.io · 1 pts · 315d
You're missing the idea of why this is cool. Recorded images only go back a couple hundred years
bravesilvernest@lemmy.ml · 19 pts · 315d
Hey, don't you bring logic in here!
dontsayaword@piefed.social · 2 pts · 315d
None of these sound like deal breakers to this great idea
Venat0r@lemmy.world · 1 pts · 313d
Also it would take at least 10 years to put a mirror there.
A_Union_of_Kobolds@lemmy.world · 1 pts · 315d
IrritableOcelot@beehaw.org · 0 pts · 315d
Only after 20 years. Light will take 10y to make it from earth to the mirror, and 10y to travel back.
Natanox@discuss.tchncs.de · 3 pts · 315d
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.
saltnotsugar@lemmy.world · 58 pts · 315d
NASA: We’ve been getting a lot of footage of you being cringy in high school.
janus2@lemmy.zip · 6 pts · 315d
oh god oh fuck there's indestructible physical evidence of my Homestuck phase
hakunawazo@lemmy.world · 3 pts · 315d
Quick, destroy the space mirror!
Dicska@lemmy.world · 3 pts · 315d
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.
harmbugler@piefed.social · 25 pts · 315d
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
niktemadur@lemmy.world · 7 pts · 315d
"Aw man... that's the third goddamned cloth I've dropped into this goddamned event horizon this week... and it's barely just Tuesday."
ChaoticNeutralCzech@feddit.org · 3 pts · 314d
Instructions nuclear, toaster stuck in black hole
ivanafterall@lemmy.world · 1 pts · 315d
Redd Foxx was ahead of his time.
mybuttnolie@sopuli.xyz · 15 pts · 315d
and if you look through the butt end of the telescope, you can see in the future
blackbrook@mander.xyz · 5 pts · 315d
Isn't the butt end, the end you normally look through? I'd think the end facing the stars would be the front end.
notsosure@sh.itjust.works · 11 pts · 315d
You may need to squint a little.
Kolanaki@pawb.social · 10 pts · 315d
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.
BuboScandiacus@mander.xyz · 12 pts · 315d
You mean, this ?
18107@aussie.zone · 4 pts · 315d
You can also watch light move with a camera.
Kolanaki@pawb.social · 4 pts · 315d
lol
Real time, tho. That way we can see photographs from before cameras, too. Watch what dinosaurs were doing n stuff.
echodot@feddit.uk · 4 pts · 315d
Unfortunately light wouldn't remain collimated over a 33 million light year distance which is what we would need to see dinosaurs
Kolanaki@pawb.social · 1 pts · 315d
How about heat? Or some other radiation? 🤔
ameancow@lemmy.world · 5 pts · 315d
InnerScientist@lemmy.world · 4 pts · 315d
But that's boring, doing it with light is way better.
Also the governments already do that and don't want to share.
ameancow@lemmy.world · 1 pts · 315d
Kolanaki@pawb.social · 2 pts · 315d
I can get nostalgia looking at my previous address on Maps because it shows my old Jetta (my first car) in the driveway :D
ameancow@lemmy.world · 4 pts · 315d
ivanafterall@lemmy.world · 1 pts · 315d
Google Earth/Maps in VR is pretty wild for visiting memory places.
Taldan@lemmy.world · 1 pts · 315d
As if we're not already doing that
ameancow@lemmy.world · 1 pts · 315d
icelimit@lemmy.ml · 2 pts · 315d
Wow that's what the movie was called. It's been on the back of my mind for years.
this@sh.itjust.works · 6 pts · 315d
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.
EddoWagt@feddit.nl · 8 pts · 314d
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
Zwrt@lemmy.sdf.org · 5 pts · 315d
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.
bravesilvernest@lemmy.ml · 4 pts · 315d
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.
Lumidaub@feddit.org · 5 pts · 315d
Satellite of Love?
homesweethomeMrL@lemmy.world · 2 pts · 315d
Sandwich of Lettuce
KurtVonnegut@mander.xyz · 3 pts · 315d
How long would a sandwich of lettuce stay fresh in space?
Archer@lemmy.world · 1 pts · 315d
Who wouldn’t love the crisp freshness of frozen solid lettuce?
homesweethomeMrL@lemmy.world · 1 pts · 315d
Science! and about $70 million dollars oughta do it. Ladies and gentlemen: the intergalactic sandwich bag!
wewbull@feddit.uk · 2 pts · 315d
Sound of Linguine
ivanafterall@lemmy.world · 1 pts · 315d
Squish of Lumbago
stevedice@sh.itjust.works · 3 pts · 315d
Yeah, but it'd take us strictly longer than N years to place a mirror N light years away form Earth, so kinda useless.
Sprawl@lemmy.world · 3 pts · 315d
We just need to point our telescopes towards the phantom zone where Zod and his buddies can reflect the light back.
Bennyboybumberchums@lemmy.world · 0 pts · 315d
Or youd see 20 years into the future... Let that one bake your noodle for a spell...
Sprawl@lemmy.world · 1 pts · 315d
No you always see into the past.
Light cannot travel back in time. The reflection you’d see in the mirror is the light that left the Earth 20 years ago.
Bennyboybumberchums@lemmy.world · 1 pts · 315d
The mirror always looks back... (insert annoying spooky laugh)
But, just to be less of a Halloween spookster. The mirror is placed in a rather exotic location in space, and between the mirror and the Earth is... wait for it... youre going to hate this lol... a naturally occurring closed timelike curve! See, I told you youd hate it lol.
echodot@feddit.uk · 1 pts · 315d
No that's not how light works. It's not 20 years either direction otherwise you could use your bathroom mirror to see into the future