What is the duration of a light event?

How long does a photon stay still?

When in time does a photon event exist?
How long does it exist at that location for?

What is the time duration of the moment of time between the future and the Past?
Can a past event be seen in the present event?

What is the duration of a light event?

until its energy is converted into another form.

How long does a photon stay still?

It doesn't. I think there have been experiments that slowed light but I'm not sure it's ever been stopped.

When in time does a photon event exist?

Like everything, in its relative present.

How long does it exist at that location for?

Until its energy is converted into another form.

What is the time duration of the moment of time between the future and the Past?

dt.

Can a past event be seen in the present event?

The past doesn't actually exist. It's an abstract. There is only now.

The past doesn't actually exist. It's an abstract. There is only now.

I would disagree. Certainly it is abstract for you as an observer but an event from your past is still propagating at v = c to other observers hence it still exists. While it may be in your past it is in others present and even others future.

I know what you mean, but I tend to think about it differently. The other people are in other reference frames so what they see is only a record of the past. For any given reference frame, the past is gone. Looking at my frame from theirs is their present.

an event from your past is still propagating at v = c to other observers hence it still exists. While it may be in your past it is in others present and even others future.The ability to observe the event propagates at c; the event does not. This therefore does not speak to the issue of whether or not past and future is separate from now.

I know what you mean, but I tend to think about it differently. The other people are in other reference frames so what they see is only a record of the past. For any given reference frame, the past is gone. Looking at my frame from theirs is their present.

We agree.

The ability to observe the event propagates at c; the event does not. This therefore does not speak to the issue of whether or not past and future is separate from now.

Technically I would probably agree but it is a bit like a tree falling in the woods. If nobody is there to hear did it make noise.

That is events only exist at their local ordinate point in their proper time. Your present is comprised of numerous past events. It is not an event to you until the information about it arrives. It then becomes an event to you.

It is not an event to you until the information about it arrives. It then becomes an event to you.
But of course when it does become an event for you it happens when?

and most importantly for how long does the event last for?

What is the duration of a light event?
I'm not familiar with the term 'light event'. An 'event' ikn the terminology of SR is simply a point in space-time. Zero duration, zero size.

Can a past event be seen in the present event?
Yes. More specifically:
In any reference frame, information may travel from a past event to a present event.

But of course when it does become an event for you it happens when?

If the event was a star 1000 light years away going supernova, then the
event happened 1000 years ago. Your OBSERVATION of the event would
be in your 'NOW'. By all indications, light does travel and it takes TIME in
the frame of reference of the observer. But if you were sitting on a photon
created when the event took place, how could you state it happened in your
'past'? An event is like a photograph that does not change for a photon. For a photon, time is always in the 'NOW', time can not pass for it.

I'm not familiar with the term 'light event'. An 'event' ikn the terminology of SR is simply a point in space-time. Zero duration, zero size.

so no matter where you look every event has zero duration, correct?
every past event and every future event has zero duration?

If this is the case what are we looking at?
Answer: Nothing.
How is it we see nothing?
Answer: Because we look to the future and see this zero moment as constant change at the rate of 'c'.
We have the past behind us and the future in front of us, but all events have zero duration so all we are seeing is the future becoming the past instantaneously.
Thus time is 2 dimensional and can only be witnessed side on as instantaneous therefore no duration therefore nothing.

A photon can therefore never exist as substance and only ever exist as effect.

the only thing that exists is a memory of constant change

it's sort of funny in a way.....an event has zero duration but yet when you add up all those zero duration events you end up with time measured.

zero + zero + zero + zero + zer + ze + z + zzzzzzzzzzzzzzzzzz........ :)

Question : How many zero duration events are needed to make up 1 second.


If each space co-ordinant has zero duration please tell me how you can measure time? Do you see the problem with mixing dimensions?
Time has to be 2 dimensional.....

edit: sorry for seeing the funny side of it all...not to be taken too seriously

But of course when it does become an event for you it happens when?


In the events future of course. :D

it's sort of funny in a way.....an event has zero duration but yet when you add up all those zero duration events you end up with time measured.

Are you familiar with integrals and derivatives?

I think there have been experiments that slowed light but I'm not sure it's ever been stopped.

Light as in photons can always and only move with the speed of c.
The experiments you speak about don't slow the photon down. As the photon passes through any matter(air, water, glass, etc) it collides with particles and is absorbed by them and then emitted again. During the time between that there is no photon, and no movement. After the photon is emitted, its moving with the speed of c again.
The illusion of slower speed is created by the fact that the particles of matter don't emit the photon immediately after absorption.

How long does a photon stay still?

modern physics is totally helpless to say what is doing the photon and other particles while they are 'still', if photon is not moving he do not have momentum, frequency and any of the properties physics can detect , then there is no way to find out that it exist until it start moving again.

Light as in photons can always and only move with the speed of c.
The experiments you speak about don't slow the photon down. As the photon passes through any matter(air, water, glass, etc) it collides with particles and is absorbed by them and then emitted again. During the time between that there is no photon, and no movement. After the photon is emitted, its moving with the speed of c again.
The illusion of slower speed is created by the fact that the particles of matter don't emit the photon immediately after absorption.

I don't think so:

http://www.news.harvard.edu/gazette/2001/01.24/01-stoplight.html

I don't think so:

http://www.news.harvard.edu/gazette/2001/01.24/01-stoplight.html

Hau explains that light entering the atomic entanglement transfers its energy to the atoms. Light energy raises the atoms to higher energy levels in ways that depend on the frequency and intensity of the light. The laser illuminating the cloud at right angles to the incoming beam acts like a parking brake, stopping the beam inside the cloud when it is shut off. When it is turned on again, the brake is released, the atoms transfer their energy back to the light, and it leaves the end of the cloud at full speed and intensity.

Photon collides with an atom. The photons energy is given to the atom. The photon does not exist anymore. The atom is manipulated to release the energy again in the form of a photon(this is why there has to be another laser). In the mean time there is no photon. Just as I said.

The low temperatures are required, because otherwise atoms would move around fast, collide, and emit the photon on themselves. And because otherwise atoms moving around, in the time the photons energy is stored in the atom, would cause the light to diffuse (diverge, disperse? not sure of the right word to use.).

But they are insinuating that it's still light inside the cloud. I know what you're saying and I can't refute you... I only know what I read of their claim. The way they write it, I gather that it's still light inside the cloud. Perhaps they are misleading.

Perhaps they are misleading.

Its probably so.. But the fact that the photon can't move slower than c, is for sure, and photons are the light, in the physical sense.

The news article was probably written so that any reader could understand it, and the didn't bother to go into details, so they just said the lightbeam is still there, and standing still. Which is not scientifically true.

Its probably so.. But the fact that the photon can't move slower than c, is for sure, and photons are the light, in the physical sense.

Well, before reading the article a year ago or so I thought the same thing, however they make claims that contradict your assertion:

Albert Einstein theorized that light cannot travel faster than 186,282 miles per second. No one has proved him wrong, but he never said that it couldn't go slower.

Hau, 41, a professor of physics at Harvard, admits that the famous genius would "probably be stunned" at the results of her experiments. Working at the Rowland Institute for Science, overlooking the Charles River and the gold dome of the state Capitol in Boston, she and her colleagues slowed light 20 million-fold in 1999, to an incredible 38 miles an hour.

Obviously, their assertion is in direct conflict with yours. I can only argue what was written. Are you sure your physics is up to date? I'm not trying to be a wise ass, I'm just asking if you're absolutely sure.

The news article was probably written so that any reader could understand it, and the didn't bother to go into details, so they just said the lightbeam is still there, and standing still.

You may be right.

Which is not scientifically true.

Again, I'd have agreed with you if their claim was not in direct conflict. It seems to me that the point of the article is to directly refute what you've asserted, that photons only travel at c.

Here I found clarification and you're right. What is captured is the information regarding the light wave:

"Physicists say they can effectively catch a light pulse in a bottle, hold onto it and release it, in an operation described as slowing light to a dead stop. It’s actually the information about the light wave that’s being captured, the researchers say, and such techniques could be applied to a future generation of quantum computers and ultrasecure communication devices."

http://www.msnbc.com/news/242698.asp

"As we decelerate, the pulse has less and less photons, and at the same time there are more and more excited spins. So when we make the light go infinitely slow ... there are no photons remaining, all of the information is in the spins,” Lukin said."

Well, its all about how you define light. If you talk about the light speed as the speed the photon is travelling, then it is always v=c.
But if you talk about lights speed - the speed it takes for the lightbeam to get from one point to another, then it can be slower aswell. In this case, the speed would be v=l/t, where t = 'time travelled' + 'time between absorbtion and re-emission'

So I guess that article should have explained it better.

so no matter where you look every event has zero duration, correct?
every past event and every future event has zero duration?

If this is the case what are we looking at?
Answer: Nothing.
It doesn't follow.

zero + zero + zero + zero + zer + ze + z + zzzzzzzzzzzzzzzzzz........

Question : How many zero duration events are needed to make up 1 second.

this is hackneyed stuff, QQ... do you want to talk about Zeno's paradox?

not really as I don't agree that I am suggesting no motion or that motion is an illusion.
What I am suggesting comes close to something like the zeno's paradoxs but is actually quite different. [not that I am all that familiar with zeno's paradox - having just read about it thanks to your question]

The point is that time is 2 dimensional and even when measured it is still two dimensional as teh measurement is always about past events recorded in a now that becomes the past instantaneously.

How does that imply two dimensions? The moment of perception still occurs in the now. It is merely a record of historical events. That only records are available to your perception doesn't seem to imply anything multi-dimensional to me, unless you're insisting the the past is real. Please explain.

Wes, I know it is difficult to grasp and certainly difficult to explain. But what we are really discussing is how time creates mass with in space, how mass is actually two dimensional but displayed in a three dimensional format.

Mass exists as a memory of change and that memory of change exists only in the NOW, so therefore time could be considered as two dimensional but is not able to be witnessed because it has no length or duration except as a memory in the NOW.

Another way to look at it is top take a slice of the end of a two poled magnet. A slice that is zero thickness. One side of that slice is north the other is south. In between North and south is zero. Apply this to light and gravity and space time and you can see that mass is actually 2 dimensional just as time is.

It is only the memory of change that creates solid mass and that memory is zero in duration as it exists also in the NOW.

The effect is 3 dimensional space and mass but the substance is 2 dimensional. because the third dimension is zero and because it is zero it has no dimension.

it's a toughy to explain and no doubt in the coming months I will try to get my thoughts out more clearly....

QQ,
If you have no problem with resolving Zeno's paradox, then you should have no problem with accepting a continuum of zero-length events.

wesmorris
First of all, thanks for link. I read it and I am sure that fo3 in principle is absolutely right: his "vision" of origins of such kind processes is a right one.
The authors of works, your link refers on, is doing a good job, but are using (absolutely deliberately!) "Sensational" lexicon to get founds ... for their researches... All this stuff "AE would be amazed", "c is not absolute constant and speed of light in vacuum cam be decreased" and so on is “a decoration” for ... ignorant mass media and financial sources. Actually they are investigating one more way to reduce speed of light in some specific medium exactly in the way as fo3 told us here...

QQ,
If you have no problem with resolving Zeno's paradox, then you should have no problem with accepting a continuum of zero-length events.

I have no problem with that, in fact it justifies my position that the now is zero length in duration, simply because time being two dimensional doesn't have "length" which is why it has the length or more precisely "depth" of a 2 dimensional object .....which is zero.

QQ,

If you could, please simply reiterate why are you assigning time more than one dimension?

SL, If I was answering the question for my ears only I would say simply because that single dimension is constantly changing at the same rate that a photon changes it's location which is 'c'.

Similar to what I know of Zenos Arrow paradox. The Now is a constantly changing zero point [zero length] dimension.

Like a universe that is constantly re-configuring itself in a continuous moment of zero duration

How does a dimension change? The time dimension is the change.

Pete, Imagine a sphere that is collecting data instantaneously form all directions simultaneously [It is not important that v=c]
As far as the sphere is concerned it is recieving information about the universe from all directions simultaneously.

As the zero duration moment changes the information the sphere is receiving is also changing in that zero length moment.

So three dimensional information is recieved by our sphere from all directions simultaneously. An infinite number of directions are possible and each information stream is of zero thickness. thus the sphere has an infinite amount of information streams coming in from all possible directions but only in the NOW. [ for our sphere ]

So we have three dimensional format of two dimensions. 2 * 2 dimesnions orthagonal to each other......

QQ, that makes no sense at all.

I think that when you use the word "dimension", you have a different concept in your head to the rest of us.

Pete as I have said I don;t expect any one to grasp what i am saying fully, however I am learning about the difficulty I face in explaining what I want to say.

Information arrives to a given point in space continuously from all directions and each information event is zero in duration [constantly changing] The point is space is also continuously changing with the arrival of that information.

What dimensionality does that suggest to you?

One time dimension and three space dimensions.

Each piece of information can be fully identified by the distance and direction it came from and the time at which it arrived.

Two numbers are required to specify the direction (eg Altitude and Azimuth). One number is required to specify the distance.

One number is required to specify the time.


Each number corresponds to a dimension.

Ahh I see where I am confusing you......I am attempoting to describe those spatial distances as 2 dimensional.....totally different toi the usual 3 dimensional with a time dimension making 4.

The sphere is in it's entirety , all of it's surface and everything with in it is an event of zero duration recieving information from all drections simultaneously as part of it's event.

So even though the sphere is commonly referred to as three dimensional it is in fact 2 dimensional.

What makes it two dimensional [the sphere]?

Let us assume for a moment that the information that is arriving impacts on our sphere at an event that has zero duration. As time passes the sphere is continuously impacted on by changing information.

Let is assume for a moment that the information takes 10 years to sink into the center of the sphere or say ten years for the full impact of the zero event to have full effect.

As that ten years passes the sphere is still continuously undergoing change that the information is imparting.

So in dimensional terms the slow progress of change on the sphere although continuing as a zero event is one dimension of change and the other is the amount of information that has passed whilst it changes...... but both are zero in duration on the x axis but have duration on the Y axis sort of thing. thus the __I__ symbol. and how 2*2 dimensional planes exist orthagonally.