Distance, Time relation and light.

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Discussion Overview

The discussion revolves around the relationship between distance, time, and light, particularly in the context of reflections in mirrors and the perception of time. Participants explore the implications of light travel time on visual perception and the concept of observing the past through light. The conversation includes speculative ideas, hypothetical scenarios, and questions about human vision and the effects of relativistic speeds.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that standing far from a mirror would result in seeing a delayed reflection of oneself, proposing that greater distance leads to longer time delays in visual perception.
  • Another participant counters that moving a meter closer to the mirror is negligible compared to the speed of light, questioning the practicality of the scenario.
  • A different participant humorously reflects on personal experiences with mirrors and questions the feasibility of seeing one's reflection from a great distance.
  • One participant proposes the use of a camera or gadget to potentially observe delayed reflections, seeking further explanations.
  • Another participant notes the impracticality of achieving the necessary speed or distance to observe such effects in everyday life, mentioning the time lag in communications with distant spacecraft as a real-world example.
  • Several participants discuss the idea that everything observed is a reflection of the past due to the finite speed of light, with some expressing uncertainty about the implications of this concept in relation to relativity.

Areas of Agreement / Disagreement

Participants express a mix of agreement and disagreement regarding the implications of light travel time on perception. While some acknowledge the concept that observations are based on past light, others question the practicality and feasibility of observing delayed reflections in mirrors.

Contextual Notes

Limitations include the assumptions about speed and distance required to observe the proposed effects, as well as the dependence on definitions of time and perception. The discussion remains open-ended regarding the implications of relativity and the nature of time perception.

Who May Find This Useful

Individuals interested in the concepts of light, time perception, relativity, and the philosophical implications of observing the past may find this discussion relevant.

maxcy03
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When we stand in front of a mirror, the image reflected is not us, it was the past of us, I am sure u guys already know that, like I stared at my friend and he stood very far away from me and all his actions were 'delayed' for a very very short time coz light needs time to travel.

How bout I stand very far away frm a mirror so that all my actions are delayed for 3 seconds and I smile and I sprint swiftly to reach a meter away from the mirror in 1 sec. Can I see all my images include the smiling one? assume that I hv great sigh and muscles. my speculative idea ' the greater the distance, the longer the time taken for an observer to see the change'.

Another question. What is our human vision and light 'refresh rate'. Why when an object almost achieve the speed of light, time slows down? Because light is the true constant? Is that object's time slows down just on our sigh?

Hope u comprehend and kindly answer.:smile:
 
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If it takes light 3 seconds to go to the mirror and back then you could just stand in one spot and get the same effect, moving a meter forward is entirely negligible when light moves at 300,000,000 m every second
 
lol, be cool. sry my language isn't that good,btw I didn't mean that. What I trying to say is that I run 899999999 meter (since the distance between me n the mirror is 900000000m) so that I am 1 meter away frm the mirror.
 
Countless times I've tried desperately to see in the mirror if I have a bald spot on the back of my head, but I was just never quick enough. If the mirror was very very far away I don't see what it wouldn't work.
 
I think it will work if we hv some kind of gadget like camera to help us,btw i need good answers and explanations.
 
You could never do this practically because of the great speed or distance you would need. You can't reach a high enough speed to see this effect in your home mirror, and any mirror you place 3 light seconds away would look so small that you would need a very very large telescope to even see it. Not to mention the fact that unless you were glowing like the Sun there wouldn't be enough light reflecting off of you, getting to the mirror, then reclecting back to see anything.

However, the idea is mostly sound. Given a large distance, you would see a time lag. Since there aren't any mirrors floating around in space we don't see reflections of us. (Not in a picture in mirror effect at least) We do however have time lag between Earth and anything out in space. The apollo astronauts had a time lag of about a second between transmit and receive times, and it only gets worse the further things are. For example, it takes over an hour for signals sent from Earth to reach the Cassini-Huygens spacecraft at Saturn. Total round trip time is 2-3 hours, requiring us to send pre-programed instructions to the spacecraft since we cannot control it in real-time.
 
thx dude. Hmm 1 more thing, is everything that we observe around us is their past? Since light need a very very short time to travel.Am I rite?
 
maxcy03 said:
thx dude. Hmm 1 more thing, is everything that we observe around us is their past? Since light need a very very short time to travel.Am I rite?

I believe that is one way to look at it. I am not familiar enough with Relativity to really be sure. I think there are a couple of different ways to view time.
 
The light that you are now seeing was emitted in the past, things might not be exactly how they appear to you (seeing light from dead stars etc...) now so yes you could say you are looking into the past.
 
  • #10
Gracias
 

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