1 light year of mirror reflections?

AI Thread Summary
The discussion explores the concept of using a series of mirrors to reflect light over a distance of one light year, questioning whether viewing the first mirror would allow one to see events from a year ago. It confirms that light takes time to travel, meaning observing distant objects like the moon shows them as they were in the past. The idea of a device that slows light down to take a year to pass through is also considered, suggesting it could allow viewing past events. One participant mentions having a device that can delay light capture, but it has limitations in terms of storage and the ability to view events in 3D. Overall, the conversation delves into the intriguing relationship between light, time, and perception.
BretN
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Just a thought...I know it is impossible, but...
What would you see in a mirror if you set up millions of mirrors, each reflected to the next mirror (each not too far apart), maybe in a spiral format, so that the total distance of reflections was one light year. The last mirror was angled to just reflect the open space.
If you looked at the "1st" mirror and saw whatever was in front of the last mirror, would you be looking at a year back in time?
 
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On the same idea... if we could create a "binocular" type device, but slow the light WAY down that passed through the device (so that it took 1 light year to go throught it), would you see 1 year into the past if you looked through it?
 
BretN said:
Just a thought...I know it is impossible, but...
What would you see in a mirror if you set up millions of mirrors, each reflected to the next mirror (each not too far apart), maybe in a spiral format, so that the total distance of reflections was one light year. The last mirror was angled to just reflect the open space.
If you looked at the "1st" mirror and saw whatever was in front of the last mirror, would you be looking at a year back in time?
Yes. If the light takes a year to get to you then you see events that happened a year ago at the source. If you look at the moon you don't see the moon where it is "now". You see it where it was about 1.3 seconds ago because that's how long it took the light from the moon to get to you.
 
BretN said:
On the same idea... if we could create a "binocular" type device, but slow the light WAY down that passed through the device (so that it took 1 light year to go throught it), would you see 1 year into the past if you looked through it?
I have a similar device at home. With some limitations I can delay the light anything from a few seconds up to a decade or more. Even watch the same event more than once. The only problem is I have to set the machine up in advance of the event. I can't watch events that I haven't captured. It's storage capacity is also limited. I can only store a few hundred hours of events so I delete the less interesting ones every now and again :-) Its not binocular so I can't see past events in 3D either.
 
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