# what we know about Time

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If we see it then its light reaches us, yes?

Yes, but there is a gap between the instant the information was send and the instant the information was received. We 'see" things at the instant we receive the information, so what we "see" is not was actually "is". The blue-dot diagram that shows what we "see" is not what actually "is".

The yellow-dot-diagram is closer to what happens. We "see" Paul at coordinates C although Paul is at coordinates B.

The blue-dot diagram shows Paul at C, as we "see" it.

It is clear like fresh water.

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...the blue-dot-diagram, which shows what we see...

If we see it then its light reaches us, yes?

Yes...

Edited by Iggy
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Again, again again you want to mix the 2 diagrams. If I draw a light ray from the black dot in this diagram, it will never reach the red dot. In this diagram, the black dot is the image of some object that was once there: it is a projection of what we see today, not what it is.

As do all the space-time diagrams in the litterature.

Edited by michel123456
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If I draw a light ray from the black dot in this diagram, it will never reach the red dot.

Like this:

That is the correct way to put light on it? That is the same as this diagram with the addition of light?

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The black dot is the actual position of Paul in spacetime. It is never observed by anyone in his actual position, except by himself.

In the whole thread you have claimed that it is physically impossible to be exactly at that point, while I have tried to no avail to explain for you that the actual position where the events are made are in the present. I think it is time that you reread the thread and then restate your position. Either you have altered you view while the discussion has proceeded or there is a growing pile of contradictions you need to sort out before it makes any sense to continue.

BTW you didn't answer my question:

At this time frame, where do observer A sees the light coming from?

From point B or point C ?

I am sorry, I thought that question was for Iggy. I think the observer at point A both sees the image and feels the gravity from point C. But when the light and gravity was emitted from Paul at point C, the observer was there in the same present as your diagram from post #167 shows:

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Like this:

That is the correct way to put light on it? (...)

Yes.

IOW the green dot is not observable by the red dot. What the red dot observes at the coordinates of the green dot is something else (another black dot not mentionned on the diagram, above the green dot and left to the red dot = point B of the following diagrams).

(...) That is the same as this diagram with the addition of light?

No, no, no. why do you insist mixing the diagrams, it is getting awesome. please re-read my explanations about the difference between the 2 diagrams. I get the feeling you don't want to understand.

In the whole thread you have claimed that it is physically impossible to be exactly at that point, while I have tried to no avail to explain for you that the actual position where the events are made are in the present. I think it is time that you reread the thread and then restate your position. Either you have altered you view while the discussion has proceeded or there is a growing pile of contradictions you need to sort out before it makes any sense to continue.

Why are you saying this at the moment you have perfectly understood my points? see below:

I am sorry, I thought that question was for Iggy. I think the observer at point A both sees the image and feels the gravity from point C. But when the light and gravity was emitted from Paul at point C, the observer was there in the same present as your diagram from post #167 shows:

Perfectly correct.

Edited by michel123456
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Why are you saying this at the moment you have perfectly understood my points? see below:

Because it is clearly not consistent with this statement:

For me the surface of the Past Light Cone is occupied by our companions traveling with us in time.

To which I have been arguing against since this thread started.

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Because it is clearly not consistent with this statement:

michel123456, on 23 March 2012 - 07:31 PM, said:

For me the surface of the Past Light Cone is occupied by our companions traveling with us in time.

To which I have been arguing against since this thread started.

But you agreed with your statement that:

I think the observer at point A both sees the image and feels the gravity from point C.

Which means: for the observer, all physics say that there is (was) an object at point C from which the observer gets light and feels gravity. All measurements, everything physically converges to the fact that there is (was) something at point C. This is what I called "our companions". All those "companions" are upon the surface of our PLC, like point C.

We know (or we should know) that in the meanwhile, the object leaved coordinates C and went somewhere close to coordinates B, as you seemed to agree lately. But Iggy (and I still wonder about you) don't accept this as true, you are believing that coordinates C remain occupied by the object "persisting" in time.

IMHO this last concept is wrong.

There is no reason why translation in space (motion) should be so radically different from translation in time (duration). when you move in space, you change coordinates, you don't 'persist" from one point in space to another. The same must be true for time: as duration occurs, you change coordinates, you don't "persist".

Edited by michel123456
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Like this:

That is the correct way to put light on it? That is the same as this diagram with the addition of light?

No, no, no.

Then you do it. Please, either put light on the diagram or tell me how to correctly do it.

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Which means: for the observer, all physics say that there is (was) an object at point C from which the observer gets light and feels gravity. All measurements, everything physically converges to the fact that there is (was) something at point C. This is what I called "our companions". All those "companions" are upon the surface of our PLC, like point C.

We know (or we should know) that in the meanwhile, the object leaved coordinates C and went somewhere close to coordinates B, as you seemed to agree lately. /snip/

You really need to make your mind up Michel, IS the object comoving in the unobservable present OR upon the observable past light cone?

It feels like I have repeated this to many times already, those two views are not consistent with each other and only one moving object.

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You are both playing with me.

Iggy is switching my answers. See my post #206 (Yes) and his post #209 (No, no, no) -edit: I'll report that.

Spyman doesn't read what I am writing.

It is not funny.

I quit

Edited by michel123456
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Then you do it. Please, either put light on the diagram or tell me how to correctly do it.

!

Moderator Note

Misquoting really isn't the done thing. Please don't do it.

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When a dicussion about Time begins, it usually derails into philosophical blah blah after a post or 2.

I'd like to refrain from the philosophical tentation, and try to concentrate on what we really know about Time from a scientific point of vue only.

For example:

1. we know that motion requires time: nothing can move from one spatial coordinate to another in zero time, it would be a transgression of the Speed Of Light.

2. we know that the rate of time is related to gravity: where gravity is stronger Time flows slower.

3. we know that time has a "direction", commonly called the arrow the time.

4. we know that time is related to causality, and causality is related to c, the Speed Of Light.

5. we know that time is linked to space: time alone has no physical meaning, only the spacetime continuum "exists".

6. we know that time can transform in space, and vice-versa: what is space for an observer may be time for another.

What else do we know about Time? (and please correct me for any error)

Time is an evolution parameter. Take a look to http://en.wikipedia....vistic_dynamics to learn more about time. See the section "Invariant Evolution Parameter Concept" and specially the subsection 1.2, which gives our modern understanding of time beyond Einstein.

That wiki page also corrects some claims in your post

Edited by juanrga
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You are both playing with me.

Iggy is switching my answers. See my post #206 (Yes) and his post #209 (No, no, no) -edit: I'll report that.

Spyman doesn't read what I am writing.

It is not funny.

I quit

I am sorry Michel, but I am NOT playing around here, I have devoted a lot of my time in this thread trying to HELP you understand.

And I have certainly read every word you have written here more than twice wondering what you wanted to say and how you meant.

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You are both playing with me.

Iggy is switching my answers. See my post #206 (Yes) and his post #209 (No, no, no) -edit: I'll report that.

Spyman doesn't read what I am writing.

It is not funny.

I quit

Excuse me? I am quoting this:

(...) That is the same as this diagram with the addition of light?

No, no, no.

I filled in the ellipsis points that you added. I did that for context so as to not make things confusing. Please, I am not playing, If I have added the light incorrectly, can you please do it, or tell me how to do it so that I can understand the diagram?

Edited by Iggy
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!

Moderator Note

Our apologies! I think the addition of the picture in your post before may have confused things. In future it is probably better to quote what someone posts exactly as they post it so that it doesn't get misinterpreted and you don't get accused of misquoting someone.

Your compensation shall be paid in cheese nips to the bank account of your choosing.

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I believe you are correct about sticking to the less confusing quoting, and I freakin' love cheese nips!

Honestly, Michel, I don't mean to be playing or to be anything but sincere. I'm curious how you would put light on this diagram. It's fine if you think I've done it wrong or if you want to explain some other reason or some other way of doing it. I just mean to ask how you would get light on that diagram.

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I believe you are correct about sticking to the less confusing quoting, and I freakin' love cheese nips!

Honestly, Michel, I don't mean to be playing or to be anything but sincere. I'm curious how you would put light on this diagram. It's fine if you think I've done it wrong or if you want to explain some other reason or some other way of doing it. I just mean to ask how you would get light on that diagram.

this diagram does not show light.

As for the other diagram:

Iggy, on 6 April 2012 - 10:09 PM, said:

Like this:

That is the correct way to put light on it? (...)

Yes.

Yes.

That was my answer in post#206.

And the (...) is important.

Edited by michel123456
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The rest of your quote, in which you stated:

(...) That is the same as this diagram with the addition of light?

No, no, no. why do you insist mixing the diagrams, it is getting awesome. please re-read my explanations about the difference between the 2 diagrams. I get the feeling you don't want to understand.

Which is what Iggy replied to, holds the same meaning with or without the entirety of post #204. The issue is moot, so please move on.

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.

.

this diagram does not show light.

Edited by michel123456
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.

.

this diagram does not show light.

Allow me to be more clear. You have frequently accused me of mixing up your two diagrams, but I believe adding light to the one diagram,

would give the equivalent of the other diagram,

except that the black dot is displaced which is something that your worldview doesn't allow because you've said that dots are objects which do not exist at multiple t values. For that reason I believe you are prevented from adding light to the first diagram.

In other words, as Spyman pointed out, I don't think you can square the diagram immediately above (the one with light on it) with the following statement,

For me the surface of the Past Light Cone is occupied by our companions traveling with us in time.

I believe you made the first diagram in this post to explain that statement and that point of view and made the second diagram to explain a different statement and a different point of view, and that the two cannot be reconciled.

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Allow me to be more clear. You have frequently accused me of mixing up your two diagrams, but I believe adding light to the one diagram,

would give the equivalent of the other diagram,

except that the black dot is displaced which is something that your worldview doesn't allow because you've said that dots are objects which do not exist at multiple t values. For that reason I believe you are prevented from adding light to the first diagram.

In other words, as Spyman pointed out, I don't think you can square the diagram immediately above (the one with light on it) with the following statement,

I believe you made the first diagram in this post to explain that statement and that point of view and made the second diagram to explain a different statement and a different point of view, and that the two cannot be reconciled.

I'd like to know what you have understood so far:

1.What does represent the first diagram?

2.what does represent the second diagram?

3.Why is the dot displaced in the 2 diagrams?

4.Do the dots represent the same thing?

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I'd like to know what you have understood so far:

1.What does represent the first diagram?

2.what does represent the second diagram?

3.Why is the dot displaced in the 2 diagrams?

4.Do the dots represent the same thing?

I have consistently asked, since post 202, for you to add light to this diagram,

I have told you that I do not understand it without the addition of light. If you could provide me with a version of that diagram with light or tell me how to correctly add light to the diagram I would be happy to answer all four questions.

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You will stay unhappy, there is no light in this diagram.

The last thing may help you is that the black dot in this diagram corresponds to point C of the other diagram.

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I would hope that we could agree that a space-time diagram which cannot include light cannot be correct.

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