1 light year of mirror reflections?

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Discussion Overview

The discussion explores the concept of observing past events through a series of mirror reflections or a hypothetical device that slows down light. Participants consider the implications of light travel time on perception and the possibility of viewing events that occurred in the past.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • Some participants propose that if a series of mirrors were set up to reflect light over a distance of one light year, looking into the first mirror would allow one to see an image from a year ago, as the light would take that long to reach the observer.
  • Others argue that the same principle applies to a hypothetical device that slows light down significantly, suggesting that if light took a year to pass through it, one would see events from a year in the past when looking through the device.
  • A participant shares personal experience with a device that can delay light for various durations, indicating that while it can capture past events, it requires prior setup and has limitations in storage and dimensionality.

Areas of Agreement / Disagreement

Participants generally agree on the concept that light travel time affects what is seen, but there are differing views on the feasibility and implications of the proposed mirror setup and light-slowing device.

Contextual Notes

Limitations include the practical impossibility of creating such a mirror setup and the constraints of the light-delaying device, which requires pre-setup and has limited storage capacity.

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 through 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 through 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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