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Quote from: Thebox on 03/09/2017 12:53:38Thank you David for explaining that. If you noticed in my diagram , at the A and B points I have not placed any bodies. My reason for this is that the absolute frame I am using is a length of space. My rocket ship is travelling a length of space from A to B points of space. My bodies of inertia reference frames are none existence in my diagram. Space is relatively an absolute frame of rest .You have an infinite number of frames of reference there whether you want them or not, and as soon as you decide that A and B are definitively stationary, you are using the absolute frame.QuoteIn my scenario the observer on the rocket ship is also not using a clock aboard the rocket ship, the observer is using the time outside of the rocket ship, i.e the light between points.The observer on the ship is a clock - we can count seconds accurately enough to tell when they don't match up to other clocks ticking at different rates. He knows that his functionality will run slow while he's moving at high speed though, so he can easily go by the time of the absolute frame instead and not be surprised by its higher tick rate.QuoteCorrect me if I am wrong, the travelling light outside of the rocket ship still measures constant in speed regardless of the observers reference frame.It does indeed (while for any other frame it is misrepresented, warped to make out that it's moving at the same speed in all directions relative to that frame).QuoteAnyway moving on , I am quite sure you aware of that we see things in their past. The absolute diagram shows that the observers see each other at the same time but are observing each other as they were 1.s ago. However this breaks down if we look at our scenario differently.In this scenario we will keep all the parameters of the thought, except this time our vector length is L=0Now do we agree that observer A and observer B who are nose to nose, see each other at the same time? They both occupy the same present/now?And the same location, so no delays in what they see of each other (apart from the time taken to process the data, but we can ignore that complication and just say it's instant).
Thank you David for explaining that. If you noticed in my diagram , at the A and B points I have not placed any bodies. My reason for this is that the absolute frame I am using is a length of space. My rocket ship is travelling a length of space from A to B points of space. My bodies of inertia reference frames are none existence in my diagram. Space is relatively an absolute frame of rest .
In my scenario the observer on the rocket ship is also not using a clock aboard the rocket ship, the observer is using the time outside of the rocket ship, i.e the light between points.
Correct me if I am wrong, the travelling light outside of the rocket ship still measures constant in speed regardless of the observers reference frame.
Anyway moving on , I am quite sure you aware of that we see things in their past. The absolute diagram shows that the observers see each other at the same time but are observing each other as they were 1.s ago. However this breaks down if we look at our scenario differently.In this scenario we will keep all the parameters of the thought, except this time our vector length is L=0Now do we agree that observer A and observer B who are nose to nose, see each other at the same time? They both occupy the same present/now?
Quote from: Thebox on 03/09/2017 14:36:24Let us look at the twin Paradox , twin two leaves twin one now. they start their journey at 00:00:00 and travel at 0.5c for 1.s.By "they start their journey", I hope you mean "they" in the singular.Quoteadded- In some way the time it takes for the light to travel from different positions in the length of journey should add up to 1.sYou have placed the twins half a lightsecond apart (I assume that the moving twin has stopped there), so the journey time for light to travel between them is 0.5s.Quoteadded- If we start with a length and interpret this as seeing things in the past, because of light and how sight works, this works and is true.They will see each other as they were 0.5s back in the past.QuoteHowever if we start within and work our way out, this becomes untrue and we don't see things in the past. So which way is correct?Hard to tell until you translate that into a form that makes sense.
Let us look at the twin Paradox , twin two leaves twin one now. they start their journey at 00:00:00 and travel at 0.5c for 1.s.
added- In some way the time it takes for the light to travel from different positions in the length of journey should add up to 1.s
added- If we start with a length and interpret this as seeing things in the past, because of light and how sight works, this works and is true.
However if we start within and work our way out, this becomes untrue and we don't see things in the past. So which way is correct?
Now this next part is a little bit complicated because the motion of observer B will be continuous and not discrete . If observer B moves at 0.5 c away from observer A, the reflected light from observer B is travelling towards Observer A and vice versus . We have already established by the synchronous of the absolute frame that both observers will continue to observe each other at the same time. So how is it possible that observer A is observing observer B in the past, when their original position and ''now'' has remained synchronous by the light through every ''step'' of the journey?
Translation : If we consider L=300,000 km then consider a photon travelling back to our eyes , we can easily see why we see things as they were 1.s ago. But if we reverse it and work our way outwards from L=0km we get an opposite result. We see the object now as it is.For this very reason do I think we have something incorrect about the nature of light.
If you start with A and B zero distance apart, they initially see each other as they are "now", but as soon as they've moved apart, delays start to come into play, and those delays are greater for B seeing A than for A seeing B. Even once B has stopped with A and B now 1 lightsecond apart, they see each other different amounts back in time until A starts to see light from B which was sent out from B when B stopped moving.
Ok , this will become our first disagreement as I see it differently. To explain my disagreement will not be easy though. I can manifest the thought experiment into pictures in my mind but I am struggling to ''see'' the times involved.
<HTML><HEAD> <TITLE>Light Delays</TITLE> <script type="text/javascript"> window.setInterval("run()",40) function run() { t++; if(t==400){s=0} // this stops the blue dot moving if(t==800){s=1; b=y; t=0} // this sends it back to the start r-=c; g+=c; // this controls the speed of the bars across the screen if(f==1){f=0; r=b; g=y; ig.style.top=2} // reuses light bars if(s==1){b+=0.5} // this moves the blue object at 0.5c if(g==150){g=-100; ig.style.top=-220} // this prevents browser window widening infinitely ir.style.left=r*4+ro; ig.style.left=g*4+go; iy.style.left=y*4; ib.style.left=b*4+bo; // yloc.innerHTML=y; bloc.innerHTML=b; } function setup() { }// All variables are created and initialised here:- c=1; t=0; f=0; s=1; y=-100; b=-100; // initial x-coord locations of the dots bo=-50; // offset to correct b's display location r=-100; g=-100; // initial locations of the bars ro=-87; go=-112; // offsets to correct bar display loc.s function send() { f=1} </script></HEAD><BODY onload="setup()" style="background-color:black;color:white;font-family:arial,helvetica,sans-serif;font-size:18pt"><blockquote> <center><H1>Light Delay Demo</H1><br><br><tt><b id="iy" style="position:relative;left:-400;top:0;font-size:60;color:yellow">.</b><b id="ib" style="position:relative;left:-450;top:0;font-size:60;color:#0020ff">.</b><b id="ir" style="position:relative;left:313;top:2;font-size:18;color:red">|</b><b id="ig" style="position:relative;left:-512;top:2;font-size:18;color:#00ff00">|</b></tt></center><p><a id="yloc"></a> <a id="bloc"></a><p><input type="button" value="Send" onclick="send()"/><p>Click the button to see the communication delays. The light (red and green bars) travels at c while the blue object travels at 0.5c.</BODY></HTML>
Ok David, I will make up a scenario. I and you are standing next to each other in our absolute frame, we see each other in a near instant, as we are now in the present. You leave me at 00:00:00 and by the power of thought you can travel at c and travel for 300,000 km , the time for you is now 00:00:01, the time for me is 00:00:01.
We are still in each others present are we not?
I do not see you as 1 second ago because 1 second ago you had not departed?
Imagine we split the 300,000 km into discrete steps, a vehicle that as travelled at 0.5c will travel 150,000 km in 1.s. The returning light to observer A will take 0.5 s to return. The other steps before 150,000 km should add up to 0.5s.
Added - although you are travelling away from me in our absolute reference frame I am relatively at rest, relative to you I am moving also , so surely David this counter acts the view of length contraction? I.e we are expanding from each other directly and proportionally.
Added- Sorry David, I am thinking out ''aloud''. If you are moving away from me at 0.5c, relative to you , it is me that is moving at 0.5c away from you.
Something is telling me that their is a counter act in this somewhere that shows we do not see things in the past.
I am still a little ''ropey'' in explaining this David, please bare with me.
Quote from: Thebox on 04/09/2017 21:40:11Ok , this will become our first disagreement as I see it differently. To explain my disagreement will not be easy though. I can manifest the thought experiment into pictures in my mind but I am struggling to ''see'' the times involved.I have modified a program that I wrote for Le Rapteux. If you click on select to highlight the code, you can then copy it and paste it into a text editor like Notepad. Once you've done that, save it while replacing the .txt ending with .htm. Then open the saved file - it should open in a browser. This should help you see what happens when light is sent out simultaneously from A and B and why B sees A as A was further back in time than A sees B.Code: [Select]<HTML><HEAD> <TITLE>Light Delays</TITLE> <script type="text/javascript"> window.setInterval("run()",40) function run() { t++; if(t==400){s=0} // this stops the blue dot moving if(t==800){s=1; b=y; t=0} // this sends it back to the start r-=c; g+=c; // this controls the speed of the bars across the screen if(f==1){f=0; r=b; g=y; ig.style.top=2} // reuses light bars if(s==1){b+=0.5} // this moves the blue object at 0.5c if(g==150){g=-100; ig.style.top=-220} // this prevents browser window widening infinitely ir.style.left=r*4+ro; ig.style.left=g*4+go; iy.style.left=y*4; ib.style.left=b*4+bo; // yloc.innerHTML=y; bloc.innerHTML=b; } function setup() { }// All variables are created and initialised here:- c=1; t=0; f=0; s=1; y=-100; b=-100; // initial x-coord locations of the dots bo=-50; // offset to correct b's display location r=-100; g=-100; // initial locations of the bars ro=-87; go=-112; // offsets to correct bar display loc.s function send() { f=1} </script></HEAD><BODY onload="setup()" style="background-color:black;color:white;font-family:arial,helvetica,sans-serif;font-size:18pt"><blockquote> <center><H1>Light Delay Demo</H1><br><br><tt><b id="iy" style="position:relative;left:-400;top:0;font-size:60;color:yellow">.</b><b id="ib" style="position:relative;left:-450;top:0;font-size:60;color:#0020ff">.</b><b id="ir" style="position:relative;left:313;top:2;font-size:18;color:red">|</b><b id="ig" style="position:relative;left:-512;top:2;font-size:18;color:#00ff00">|</b></tt></center><p><a id="yloc"></a> <a id="bloc"></a><p><input type="button" value="Send" onclick="send()"/><p>Click the button to see the communication delays. The light (red and green bars) travels at c while the blue object travels at 0.5c.</BODY></HTML>QuoteOk David, I will make up a scenario. I and you are standing next to each other in our absolute frame, we see each other in a near instant, as we are now in the present. You leave me at 00:00:00 and by the power of thought you can travel at c and travel for 300,000 km , the time for you is now 00:00:01, the time for me is 00:00:01.Yes, so long as I correct my clocks to make up for the time they lost while moving.QuoteWe are still in each others present are we not?Absolutely.QuoteI do not see you as 1 second ago because 1 second ago you had not departed?Correct - you will see me half way across to the place where I stopped, so you're seeing me as I was half a second back in time (because I was there half a second ago and the light took half a second to reach you from there). I will see you as you were a whole second ago though, because the light that's now reaching me from you set out a second ago.QuoteImagine we split the 300,000 km into discrete steps, a vehicle that as travelled at 0.5c will travel 150,000 km in 1.s. The returning light to observer A will take 0.5 s to return. The other steps before 150,000 km should add up to 0.5s.You've returned to the previous scenario, and that's the one my program illustrates. The vehicle reaches the 150,000km point in 1 second and sees A as A was half a second ago. The light that is reaching A from B though is not the light now leaving B (because that will take another 0,5s to reach A), but light that left B a third of a second before B stopped.QuoteAdded - although you are travelling away from me in our absolute reference frame I am relatively at rest, relative to you I am moving also , so surely David this counter acts the view of length contraction? I.e we are expanding from each other directly and proportionally.Length contraction hasn't come into this in any relevant way, although B will be contracted in length while moving.QuoteAdded- Sorry David, I am thinking out ''aloud''. If you are moving away from me at 0.5c, relative to you , it is me that is moving at 0.5c away from you.If you want to change the absolute frame so that A is moving instead of B, what then happens is this. A and B are initially moving, but B stops for a while. B imagines that its clock is running slow, so it starts moving again early, thereby ensuring that their separation is shorter in distance than it was in the previous case where A was at rest in the absolute frame. That is length-contraction.QuoteSomething is telling me that their is a counter act in this somewhere that shows we do not see things in the past.Of course we see things in the past, the only exception being when there is no light delay because we are zero distance away from the thing we're looking at.QuoteI am still a little ''ropey'' in explaining this David, please bare with me.Is that an invitation to the sauna?
Ok David, I will attempt the script later thank you.
At this time I am still in disagreement with that we see things in the past. The exception of d=0 where we see each other in the present playing a part. I can not ''see'' how somebody can move away from me , then I am in some way seeing them in the past, they were at now when they left me so my thoughts are saying it seems obvious we see them now but just a distance away.
I am looking at an object now in my room that is a short distance away, I understand the time light takes to reach my eyes is almost negligible.
But I can not understand why light would need to travel to my eyes from the object when I can clearly see and measure the entire distance to the object.
My thinking on this is that I am seeing that object in its exact location and now, this of course being measurable relative to myself.
The same obviously applying to greater distances.
So if I can see the entire distance, measure the distance, am I not seeing visible light in its exact location?
Quote from: Thebox on 06/09/2017 13:14:10Ok David, I will attempt the script later thank you.I'm hoping you can get it to work, because this will allow you to change numbers in it to prove to yourself that the program really does what's claimed of it, and it might encourage you to try other experiments with programming which will help you understand things better.QuoteAt this time I am still in disagreement with that we see things in the past. The exception of d=0 where we see each other in the present playing a part. I can not ''see'' how somebody can move away from me , then I am in some way seeing them in the past, they were at now when they left me so my thoughts are saying it seems obvious we see them now but just a distance away.There is a delay of one nanosecond for every 30cm of separation. That can't stop happening just because someone starts off right next to you before moving away. The delay is directly proportional to how far away they are from you (or how far away they were at the time when the light left them). QuoteI am looking at an object now in my room that is a short distance away, I understand the time light takes to reach my eyes is almost negligible.One nanosecond of delay for every 30cm, so if it's at arm's reach, it's going to be two nanoseconds of delay. A slightly longer delay applies to any signals you get from touching it, although it's not impossible that they may get your attention faster because visual processing may be slower.QuoteBut I can not understand why light would need to travel to my eyes from the object when I can clearly see and measure the entire distance to the object.How else are you going to be able to see it without light travelling from it to you?QuoteMy thinking on this is that I am seeing that object in its exact location and now, this of course being measurable relative to myself.It seems that way because the delays are too short for us to perceive.QuoteThe same obviously applying to greater distances.With greater distances, the delays add up to significant ones, but our thinking is too slow to pick up on it until we start talking to people on the moon.QuoteSo if I can see the entire distance, measure the distance, am I not seeing visible light in its exact location?You're always seeing the light in your eye - the retina is covered in sensors that feel light, but that light is no longer touching the objects it came from - it has taken time to get from there to your eyes.There's an experiment I'd like you to try out which doesn't have anything to do with delays due to the time light takes to get to your eyes, but it does make you think a bit more about how "now" actually relates to what you're seeing. Find a gadget like a pocket radio with an LED light on it which lights up when it's tuned in correctly. Then go into a dark room, but make sure there's some light coming in through the door from a lit area. Start in the darkest corner and move into a brighter area if you can't see the radio. Once you can see it, stop. (If you can see it too easily even in the darkest corner, close the door a bit to make the room darker - you want it to be on the edge of visibility.) Now switch the radio on and tune it until the LED lights up. Next, wave the radio from side to side gently, starting slowly and speeding up if necessary. You should find a frequency of this movement at which you see the light and the radio moving in opposite directions - the LED appears to detach from the radio and move independently of it. This happens because you process brighter parts of the scene more quickly than dark parts, so different parts of the image get through to you out of sync with each other. Notice how hard it is to work out which part of what you're seeing matches up with which way you feel that you are moving the radio.All inputs reach our consciousness with delays, so we're never seeing now. The delays from light taking time to cross the space between us and the things we're looking at are trivial in comparison with these other delays, until we look away from the Earth towards the moon, sun and stars, and then the delays caused by processing are the ones that become trivial in comparison with the years and centuries of delay caused by great distances (and two million years of delay when we look at the M31 galaxy).
However I still can not accept this to be true when the logic says something different.
Now must be still now for either observer so how can we be seeing them in the past? Surely we are seeing them now a distance away?
Also you avoided commenting on the distance observed between observers. Both observers can see the entire length between them. Also there is fact that I do not see individual photons with my eyes.
I want you to imagine a light sphere please David that was the size of the visual Universe, however I want you to imagine this as you being an infinite space. Could you imagine that relative to you the Visual Universe is a 0 point and all the information within this point is contained at the same time. So unless somebody travels to the dot or the dot travels to you, you can not observe the information in the dot until the light sphere enters yours eyes.
I do not 'see' photons like you and science 'see' photons. I believe electromagnetic radiation as to enter your eyes to allow you connectivity to the dot. The thought of propagating waves through space is on par to a torpedo travelling through an ocean.
In the above picture there is two equal dimensions visual Universes, the one on the left you can observe as a visible universe. The one on the right you also observe but as a black hole. The one on the left is near, the one on the right is far.
If only father Ted knew how good the science was involved in that gag hey, I did!
Why can't the black one be nearer than the white one?
I didn't avoid it - I just couldn't see the relevance of it. How can you see the distance?
How is logic saying something different?
Ok David I can 'see' that my thoughts on this are ahead of your understanding .
I never said there was a ''black one'' in the picture.
We can see the distance because space is not opaque. I can certainly see A and B points in our scenario at the same time in a single frame whole. We can measure the space between the points we are observing. How can you not see the distance?
Because the notion makes no sense to reality, the reality is the space is transparent and is not opaque to sight , we simply see through this space which seems more logical and reality.
Objectively if I can see the entire distance from my eye to an object , I am seeing that object now a distance away.
p.s The light propagating through space is not the same as a radio wave.
You said "The one on the right you also observe but as a black hole." But misunderstandings are inevitable if you present people with loose wording (how do you observe the invisible thing that you now say isn't there) and a black flag with a white spot on it to serve as a diagram.
You don't see distance - you see things at a distance and calculate how far away they are based on how they appear, and if they're close enough you use your stereo vision to help calculate the distance. And while you see light from A and B at the same time, those are two lots of light which have taken different amounts of time to reach you, so it did not leave A and B at the same time.
If something is completely transparent, you can't see it. You would only see space if it wasn't transparent.