# Thread: Everywhere at Once

1. Just trying to clear my mind of some stuff. I have read articles that say for the photon there is no space or time and it is everywhere at once. Because a photon doesn't experience time or space* then it basically arrives at its destination instantly. If the photon is everywhere then does it have anywhere to go? Is everywhere at once the same as quantum superpositioning? Once observed the photon's journey ends so is this the same as collapse of the wave function?

* it seems strange to me that a photon's flight path is shaped by the geometry of space time yet it experiences neither

2.

3. Articles that say that a photon is "everywhere at once"*, or that they don't experience space or time are misleading. Space and time are undefined for a photon. The problem with such statements is that they try to extrapolate the Lorentz transforms into a region where they don't apply. For example, consider the time dilation equation. As v approaches c, a clock moving with respect to us is measured as ticking slower and slower. One is tempted to say that at v=c the clock will stop completely. However, the actual formula looks like this:
T = t'/(sqrt(1-v^2/c^2), where t' is the time ticked off by the clock moving relative to us and T is the time we measure for it to tick off that much time. If v = 0.99c and t'= 1sec, then T= 7 sec. Meaning that it will take 7 sec by our clock for the moving clock to tick off 1 sec.
The closer v gets to c, the longer the time it takes by our clock for the moving clock to tick off 1 sec. T approaches infinity as v approaches c. However, this does not mean that T= infinity when v=c.

If v=c then the equation reduces to T=t'/0. Division by zero is undefined and does not equal infinity.

What this comes down to is that c is not a valid reference frame from which one can make measurements and it is meaningless to talk about what happens from a photon's frame of reference.

And no, this has nothing to do with Quantum Mechanics.

* even if we take the the view that length contraction as measured by the photon would have the universe contracted to zero length, this does not put the photon as being "everywhere at once", only "at every point along its path". So for example, a photon that from our frame was traveling from Sun to Earth travels along a line. That photon would measure that line as being a point. A single point on a plane that the universe has been length contracted to. It would not consider itself to be at every point of that plane. But even this is an invalid viewpoint as explained above.

4. Originally Posted by Janus
Articles that say that a photon is "everywhere at once"*, or that they don't experience space or time are misleading. Space and time are undefined for a photon. The problem with such statements is that they try to extrapolate the Lorentz transforms into a region where they don't apply. For example, consider the time dilation equation. As v approaches c, a clock moving with respect to us is measured as ticking slower and slower. One is tempted to say that at v=c the clock will stop completely. However, the actual formula looks like this:
T = t'/(sqrt(1-v^2/c^2), where t' is the time ticked off by the clock moving relative to us and T is the time we measure for it to tick off that much time. If v = 0.99c and t'= 1sec, then T= 7 sec. Meaning that it will take 7 sec by our clock for the moving clock to tick off 1 sec.
The closer v gets to c, the longer the time it takes by our clock for the moving clock to tick off 1 sec. T approaches infinity as v approaches c. However, this does not mean that T= infinity when v=c.

If v=c then the equation reduces to T=t'/0. Division by zero is undefined and does not equal infinity.

What this comes down to is that c is not a valid reference frame from which one can make measurements and it is meaningless to talk about what happens from a photon's frame of reference.

And no, this has nothing to do with Quantum Mechanics.

* even if we take the the view that length contraction as measured by the photon would have the universe contracted to zero length, this does not put the photon as being "everywhere at once", only "at every point along its path". So for example, a photon that from our frame was traveling from Sun to Earth travels along a line. That photon would measure that line as being a point. A single point on a plane that the universe has been length contracted to. It would not consider itself to be at every point of that plane. But even this is an invalid viewpoint as explained above.
Does the statement that the photon does not have a valid frame of reference have an interpretation that is not simply based on the mathematics?

Or is is similar to the way that a "singularity" is a point where we throw up our hands and say " the preceding no longer applies and we just don't know what happens"?

Also this invalid FOR as it applies to the photon,does it equally apply to any massless object (do they all travel at c in a vacuum?)

Is it important to consider that the photon is traveling at the universe's maximum speed possible under any conditions whatsoever?

5. What up, Zinman? Are you trying to steal my candle design? It was just a saying that I made up to put on a candle for a Christmas gift.

Nothing happens at once. At once is not everywhere. Only light is everywhere and everywhere at once.

It’s just a fun thought experiment and Ethan Siegel did say that infinities don’t always mean physics is wrong; they often mean that physics does something unintuitive.

When you move at the speed of light, this means the following:
You must be massless.
All the distances along your direction of motion will be contracted down to a single point.
And you will not experience the passage of time; your entire journey will appear to you to be instantaneous.
Here's something interesting that I picked up somewhere or another.

The speed of light is more about the speed of causality. Casual connection gives us the only ordering of events that all observers will agree on.

Why does causality have a maximum speed?

There’s a velocity dependent tradeoff between the electric vs. magnetic fields. The two work together to give you the same Lorentz force regardless of the reference frame. The electromagnetic force holds clues to the interplay between time, space, and velocity.

Eistein realized that the Lorentz transformation tells us how space and time are connected and that it predicts the speed of causality.

The existence of mass, space, and time tells us that the universal speed is finite. If c was infinite, there would be no matter because it would take infinite energy to make any mass. There would be only massless particles traveling at infinite speed. There would be no time, space, and no Zinman.

6. Originally Posted by Secular Sanity
What up, Zinman? Are you trying to steal my candle design? It was just a saying that I made up to put on a candle for a Christmas gift.

Nothing happens at once. At once is not everywhere. Only light is everywhere and everywhere at once.

It’s just a fun thought experiment and Ethan Siegel did say that infinities don’t always mean physics is wrong; they often mean that physics does something unintuitive.

When you move at the speed of light, this means the following:
You must be massless.
All the distances along your direction of motion will be contracted down to a single point.
And you will not experience the passage of time; you entire journey will appear to you to be instantaneous.
Here's something interesting that I picked up somewhere or another.

The speed of light is more about the speed of causality. Casual connection gives us the only ordering of events that all observers will agree on.

Why does causality have a maximum speed?

There’s a velocity dependent tradeoff between the electric vs. magnetic fields. The two work together to give you the same Lorentz force regardless of the reference frame. The electromagnetic force holds clues to the interplay between time, space, and velocity.

Eistein realized that the Lorentz transformation tells us how space and time are connected and that it predicts the speed of causality.

The existence of mass, space, and time tells us that the universal speed is finite. If c was infinite, there would be no matter because it would take infinite energy to make any mass. There would be only massless particles traveling at infinite speed. There would be no time, space, and no Zinman.
That bolded part is a great observation. The rest of your post is extremely interesting too.Have you any references where these particular observations are is gone into in further detail ?(I know you said this is what you picked up along the way)

I have been scratching my head over this "speed of causality" question for quite a while now

eg here is a question I asked some while back https://physics.stackexchange.com/qu...al-speed-limit

7. Are photons (or electrons) real or mathematical models? I assume that only if they need to interact they pop into existence from a probability wave.

8. I like to think of the model and the reality as two sides of the same coin. Either one creates the other.(well the model only attempts to (re) create the reality.)

Both "feed off" the other.

9. I look into the night sky and a photon which was made in a star light years away enters my eye and is lost. Sad ending for it after all that time, especially as it should have missed the earth altogether. Somehow I don't think I could be that lucky. By some sort of chance in the feint radiation is a potential particle which manifests itself in my eye because a very small part of the wave has interacted.
Does anything in nature exist until it is forced to? I think you could include both physics and biology.
Then, if nothing exists, does nothing exist?
Is this where reality breaks down?

10. Originally Posted by ox
Then, if nothing exists, does nothing exist?
Is that a misprint? If that's what you meant to write it is like asking"if all men are wife beaters are all men wife beaters?" Well ,yes.

Did I miss something?

11. What up, Zinman? Are you trying to steal my candle design? It was just a saying that I made up to put on a candle for a Christmas gift.
Not sure what you're saying SS....did I do or miss something? Oh wait...everywhere at once has everything to do with the candlelight emitted from a waxed wick you've designed?.. Apparently you've asked in a post, not sure if here or another forum, for readers to design a candle for Xmas? First I've heard of it and if so then something caused me to miss it.

How about I call my candle 'nowhere at once"? However I'm not very crafty, so don't count on it.

For the photon...would going nowhere be the same as a photon going somewhere instantaneously?

12. Originally Posted by zinjanthropos
What up, Zinman? Are you trying to steal my candle design? It was just a saying that I made up to put on a candle for a Christmas gift.
First I've heard of it and if so then something caused me to miss it.
Yeah, a brain fart. Men are more forgetful than women, aren't they?

Some of Dywyydyr's remarks have been deleted because they were not what I was looking for. They were boring, irrelevant, lacking wit, etc.

Maybe I can explain it easier through some of the historical aspects.

Since light is a transverse wave, we needed a semisolid substance, not just a fluid, because a fluid can’t hold a sheer force. That’s why the idea for an ether was born. I think it was Thompson who tried to build a mechanical model with rotating fluid because vortex rings can be very stable and offer more resistance. Maxwell liked this idea and begins to add to this model, which led him to understand how light is connected to electromagnetism. He is able to calculate what the speed for a transverse wave would be in this model and is within 1% of c. Analogies never deliver airtight insight, that's why we say that his physical descriptions are the equations themselves. It was difficult for even the most well-known intellectuals to grasp. He used mostly Cartesian notations, because he did not like vector notations, and France and Germany were using Laplacian notations, which made it difficult to translate. Hermann Von Holtz agreed with his results but even he could not grasp the actual physical conditions of this statement. Maxwell indicated that this field was primary and charges and currents secondary, the charges and currents were not physical entities themselves but a consequence of this field. Many remained in denial and did not want to give up the concept of ether.

Einstein borrowed the constancy of the speed of light from the Lorentz ether theory. Lorentz and Poincare had already found it necessary to invoke the principle of relativity itself in order to make the theory match the empirical data and it became equivalent to special relativity.

Having the speed of light remain the same when switching between inertial frames meant that the distance and time would change under the Lorentz transformations, but with this, special relativity eliminated the need for the mechanical nature of the Lorentzian ether. It took away the need for an immobile, semisolid substance, i.e. an ether.

The universal speed limit isn’t really connected to electromagnetic waves (light). It is a consequence of the structure of space-time.

https://en.wikipedia.org/wiki/Lorentz_ether_theory

https://en.wikipedia.org/wiki/Minkow..._and_causality

https://en.wikipedia.org/wiki/Causality

13. What readers of this forum should know is that the SciVillage forum is also called the Casual Discussion Science Forum. It encourages talk re science plus the other regular subforms, but doesn't ask for proof of what you say. It's like regular armchair scientists sitting around a campfire throwing around their imagination/opinions. I'm comfortable there because I have no delusions about being an expert on anything scientific. Doesn't mean you won't get called out, however you're not required to issue a proof. Problem is very few members

Yeah, a brain fart. Men are more forgetful than women, aren't they?
Can't forget if I never looked at it. Did you forget to ask yourself that i may be prone to skipping over stuff? Selective hearing I do have but I guess I'm a selective reader as well. If that makes me forgetful then so be it. No big deal.

Anyway, before the quoted SciV thread became a pissing match it was interesting. Now I was left with a choice,...take your word for it or go after other opinions. That's why I asked the question here.

14. Originally Posted by geordief
Originally Posted by ox
Then, if nothing exists, does nothing exist?
Is that a misprint? If that's what you meant to write it is like asking"if all men are wife beaters are all men wife beaters?" Well ,yes.

Did I miss something?
I was hoping that someone here can explain what nothing is and resolve this paradox.
Unless something is illuminated by light then why should it have any reality?
In the beginning was light, except that it takes roughly a million years for a star to illuminate. Before the 'creation' and up until the cosmos was filled with light, was there nothing (I'll ignore religious explanations).
So what is nothing, and are we asking the right question?
If I'm to believe Dirac then 'the world is not made of things, it's constituted of an abstract mathematical structure which shows us how things appear and how they behave when manifesting themselves' (quoted from Carlo Rovelli, Reality Is Not What It Seems).
Can I interpret this as prior to the beginning there was abstract mathematical reality?

15. I am not familiar with the concept of an abstract mathematical reality.It reminds me a bit of the (Platonic?) idea that the world is made up of "ideas " ("redness" being one such "unit of reality.")

So I won't comment as I am not familiar enough with the subject (is it idealism vs materialism?)

However I think I have gleaned that the universe could sill exist even if light (em radiation ) was not a constituent part.

What is "nothing? That may be a question that resolves itself or dissipates itself no sooner than asked and so may not require an answer.

Against that , are we really supposed to accept that holes don't exist physically?There are so many of them if they don't.

16. What is "nothing?
A philosophical question of the ages and in my mind one of the most popular. Don't think we can observe nothing directly nor can it be somewhere. I think in a broad sense it is an intangible something or maybe its analogous to wave/particle duality, where reality is either something or nothing...idk. Not saying there's a metaphysical universe out there running parallel to our physical specimen.

I don't remember who said it but I can still remember the words, "this (the observed) is what nothing looks like".

17. Aw, c’mon guys! Janus answered the original question very well. As far as Relativity (or any other accepted physical model) goes, it is wholly mathematical. The model is predicated completely on mathematics and follows only mathematical rules. The physical implications of division by zero being undefined is that calculating coordinate times from a c FOR are undefined.
Now! Please take your philosophical musings to the appropriate sub forum. Thank you.

18. Originally Posted by GiantEvil
Aw, c’mon guys! Janus answered the original question very well. As far as Relativity (or any other accepted physical model) goes, it is wholly mathematical. The model is predicated completely on mathematics and follows only mathematical rules. The physical implications of division by zero being undefined is that calculating coordinate times from a c FOR are undefined.
Now! Please take your philosophical musings to the appropriate sub forum. Thank you.
I'll go along with that and not going to argue with you, yet some might. However I don't think just because it's mathematics that it's entitled to a "Get out of Philosophy Free" card.

You can decide:https://en.wikipedia.org/wiki/Philosophy_of_mathematics

19. I guess I should append an “And I will likely join you there.” To my previous post.
No, I am very interested in mathematical philosophy. Just not in the physics section, and a little more disciplined in it’s discussion.

20. As I indicated in OP my intentions are to get things straight in my mind.

So what I gather and as far as distance goes, objects either appear or are much closer to each other when travelling while approaching light speed. IOW'S because I'm comparatively mega slower than a photon moving thru cosmos, the universe appears extremely large. To a photon, the vast distances within the universe are practically non existent, as it can instantly be where it's going to. The difference between me and the photon is that I would have to gradually increase my velocity, so when traversing space between A and B, the distance would shrink as I sped up whereas the photon is instantly accelerated to c, thus instantaneous.

Time however slows down for a traveller as c is approached or during acceleration. One second of a traveller's time actually is a longer time for someone moving at a slower speed. So when travellers moving faster than a slower speed return to a slower speed, they have arrived in the future. I don't think it's the traveller's future but the future for all things moving at that particular slower speed. This hard to put down in words, need to improve my physics vocabulary.

Now because of this and if everything moved at c, then time for all intents wouldn't exist. Time seems like the energy of the coiled spring of a mousetrap just waiting to be unleashed. Time slows down and distances shrink, both to zero, if something moves at c. I assume at a moment when everything moves at c the universe is merely a point. I'm thinking the universe owes its existence to the presence of a slow moving observer..... damn , I didn't want to get philosophical.

How am I doing?

21. Originally Posted by zinjanthropos
I assume at a moment when everything moves at c the universe is merely a point.
No. Length contraction occurs only in the direction of travel.

22. Originally Posted by KJW
Originally Posted by zinjanthropos
I assume at a moment when everything moves at c the universe is merely a point.
No. Length contraction occurs only in the direction of travel.
Can't figure out the proper way to say what I meant. Thanks for correcting that statement.

Is there a direction if everything moved at c? Isn't direction of motion always forward? I need more straightening out here.

23. Originally Posted by KJW
Originally Posted by zinjanthropos
I assume at a moment when everything moves at c the universe is merely a point.
No. Length contraction occurs only in the direction of travel.
One further point: Suppose there is a photon trajectory in spacetime between event A and event B. Although the proper distance between A and B is zero, they are not the same point.

24. Originally Posted by KJW
Originally Posted by KJW
Originally Posted by zinjanthropos
I assume at a moment when everything moves at c the universe is merely a point.
No. Length contraction occurs only in the direction of travel.
One further point: Suppose there is a photon trajectory in spacetime between event A and event B. Although the proper distance between A and B is zero, they are not the same point.
Hopefully not too off topic,(I may have asked this before and be banging my head again) is the reason we have all these time/distance apparent strangenesses simply because we can only use (as a final recourse**) objects that move at c to make measurements between events in a moving environment ...and it is absurd to ask a measuring instrument to "measure itself"?

We are fooled by the apparent readiness of objects to "stand still" for us --they never actually do....

**a central bank might be an analogy

25. Originally Posted by GiantEvil
Aw, c’mon guys! Janus answered the original question very well. The physical implications of division by zero being undefined is that calculating coordinate times from a c FOR are undefined.
Did he?

Postulates of special relativity:

1. The laws of physics are the same in all inertial reference frames.
2. The speed of light in vacuum is the same in all inertial reference frames.

It’s relative to the stationary observer. If light was at rest it would violate the second postulate of SR.

https://en.wikipedia.org/wiki/Postul...ial_relativity

Originally Posted by GiantEvil
Now! Please take your philosophical musings to the appropriate sub forum. Thank you.
It’s not necessarily philosophy. We use thought experiments in various areas of study but they’re particularly useful in physics.

Originally Posted by geordief
and is it absurd to ask a measuring instrument to "measure itself"?
By Geordief, I think he’s got it. And with no scientific background.

Well done!

Even if it could be done, relative to itself, a reference frame is at rest and experiences neither length contraction nor time dilation.

26. Where the bloody hell did I ever say, or imply “light at rest”?
Go back and read stuff over dude.

27. Originally Posted by GiantEvil
Where the bloody hell did I ever say, or imply “light at rest”?
Go back and read stuff over dude.
Where in the hell did I say that you did say that?

Err, that was my answer.

Relative to itself, a reference frame is at rest, duh.

You go back and reread it, dude.

28. I’ll just let the record stand. People may judge for themselves.

29. Was looking at this article, https://sciencing.com/long-photons-e...ide-10063.html

Mentions that photons within the Sun are constantly absorbed and reemitted before reaching the surface. The distances they travel between these events determines how long it takes. So does this mean the photon that eventually leaves the Sun is the same one that started the journey?

Takes years apparently for this photon to travel from the Sun's core to surface. I'm thinking the photon doesn't really slow down but changes direction so many times that it appears to be slowed down. Would this be correct?

When photons collide within the sun or elsewhere in space, does one absorb the other or do they just deflect?

30. My understanding is that a light wave propagates in all directions and a photon appears wherever that light wave interacts with an object.

So yes maybe it is a pinball effect and it is not the same photon that started its journey but a reincarnation zillions of times over.

Not sure if photons (light waves) ever collide(thought they didn't except perhaps under exceptional circumstances but don't know much about it...)

31. Originally Posted by geordief
My understanding is that a light wave propagates in all directions and a photon appears wherever that light wave interacts with an object.

So yes maybe it is a pinball effect and it is not the same photon that started its journey but a reincarnation zillions of times over.

Not sure if photons (light waves) ever collide(thought they didn't except perhaps under exceptional circumstances but don't know much about it...)
I didn't think they collided either. When I check this out I keep seeing the term elastic collision but so far not able to find out what exactly that means. Maybe someone can help here.

By interacting, do they mean the photons don't actually touch but produce some sort of an effect? I've seen virtual particles mentioned in these articles and was wondering if that's what the effect, assuming there is one, that interacting photons produce?

32. Originally Posted by zinjanthropos
Originally Posted by geordief
My understanding is that a light wave propagates in all directions and a photon appears wherever that light wave interacts with an object.

So yes maybe it is a pinball effect and it is not the same photon that started its journey but a reincarnation zillions of times over.

Not sure if photons (light waves) ever collide(thought they didn't except perhaps under exceptional circumstances but don't know much about it...)
I didn't think they collided either. When I check this out I keep seeing the term elastic collision but so far not able to find out what exactly that means. Maybe someone can help here.

By interacting, do they mean the photons don't actually touch but produce some sort of an effect? I've seen virtual particles mentioned in these articles and was wondering if that's what the effect, assuming there is one, that interacting photons produce?
You didn't misread "proton" for "photon" did you? Is that why you are wondering if photons collide?

I think I saw that an "elastic collision" meant no kinetic energy was lost (first time I heard it)

33.

34. You didn't misread "proton" for "photon" did you? Is that why you are wondering if photons collide?
No, whether photons collide or not wasn't my first thought. My question was a segue to the following.... I was hoping to find out if for any reason a photon from one light source could be contained in the photon stream of another. How would I know what hits my eye isn't a photon from another source?

Laying in bed, translucent curtains drawn, light passing thru to my eyes. Is there any way I could tell, other than opening the curtains to see, if there's one source of light or multiples? That's how this started.

35. Originally Posted by zinjanthropos
You didn't misread "proton" for "photon" did you? Is that why you are wondering if photons collide?
No, whether photons collide or not wasn't my first thought. My question was a segue to the following.... I was hoping to find out if for any reason a photon from one light source could be contained in the photon stream of another. How would I know what hits my eye isn't a photon from another source?

Laying in bed, translucent curtains drawn, light passing thru to my eyes. Is there any way I could tell, other than opening the curtains to see, if there's one source of light or multiples? That's how this started.
Are you thinking of of interference?

I think any individually detected photon could be the result of any amount of separate light waves combining previously before it hits a screen or an eye.

On the "other" hand I have heard that some distant astronomical objects have been detected by the arrival of a single photon ....but even then maybe at source there had also been combining of light waves all those thousands of light years ago.

36. Are you thinking of of interference?
Sort of like when your radio picks up a signal for another that overrides or mixes in with your favourite channel? I guess. I just thought that if for any reason a photon from another source is deflected that the angle of deflection might cause it to get in line with the photons hitting your eye. Are my eyes always getting mixed signals from light sources? What if we had two Suns?

37. Originally Posted by zinjanthropos
Are you thinking of of interference?
Sort of like when your radio picks up a signal from another that overrides or mixes in with your favourite channel? I guess. I just thought that if for any reason a photon from another source is deflected that the angle of deflection might cause it to get in line with the photons hitting your eye. Are my eyes always getting mixed signals from light sources? What if we had two Suns?
Well suppose there are two sources (two incandescent bulbs on the moon separated by a distance from each other by a convenient distance)...

As the separate light waves come through the Earth's atmosphere it might happen that one wave will be deflected into the other.

In that scenario we might ,with the naked eye have difficulty discerning two separate images no matter what degree of definition or focus we employed. (the two waves might interfere if the atmosphere was sufficiently turbulent and dense)

2 would have become one.

I may be wrong of course. I am trying to learn as well.

38. On the "other" hand I have heard that some distant astronomical objects have been detected by the arrival of a single photon ....but even then maybe at source there had also been combining of light waves all those thousands of light years ago.
I don't understand optics but I've often wondered if what you say in the quote is true. If I gazed at a star in the night sky and my eyes had an aperture that only permitted one photon, would I still see the same image I see of the distant star as I do today with my current equipment?

In that scenario we might ,with the naked eye have difficulty discerning two separate images no matter what degree of definition or focus we employed. (the two waves might interfere if the atmosphere was sufficiently turbulent and dense)

2 would have become one.

I may be wrong of course. I am trying to learn as well.
Myself as well. I think as I get farther away then those two lights on the moon would be seen as one. idk

39. Originally Posted by zinjanthropos

Myself as well. I think as I get farther away then those two lights on the moon would be seen as one. idk
I am not sure how that works in a vacuum. If you have two mutually close sources of light that emit simultaneously and are detected at a third location I am not sure if they would not interfere with each other .

So I just don't know how many lights an observer would see....

40.

41. Thanks. Really interesting but I wish I was better placed to understand it

42. Originally Posted by geordief
Thanks. Really interesting but I wish I was better placed to understand it
Points out one of the most fundamental problems with Fizzicks. Laymen can't express themselves in a scientific way whereas physicists can't express in laymen's terms. Both camps think the other guy understands.

43. Easier for bluffers to be caught out in science than in other areas of learning?

44. Originally Posted by geordief
Easier for bluffers to be caught out in science than in other areas of learning?
Well if I wasn't caught out then I'd go around not knowing. Im OK with it all.

The Hubble deep field image. I'd post a pic but don't know how but I think everyone has seen it. Anyways found an article that says the following:

More than 20 years ago, the first Hubble Deep Field image was taken. By pointing at a blank patch of sky and collecting single photons for days on end, it was able to reveal what lies out there in the great cosmic abyss: billions and billions of galaxies.
What exactly do they mean by single photons? They're not talking one at a time are they? Probably a simple answer but wording like this starts my layman's wheels spinning.

45. Originally Posted by zinjanthropos
Originally Posted by geordief
Easier for bluffers to be caught out in science than in other areas of learning?
Well if I wasn't caught out then I'd go around not knowing. Im OK with it all.

The Hubble deep field image. I'd post a pic but don't know how but I think everyone has seen it. Anyways found an article that says the following:

More than 20 years ago, the first Hubble Deep Field image was taken. By pointing at a blank patch of sky and collecting single photons for days on end, it was able to reveal what lies out there in the great cosmic abyss: billions and billions of galaxies.
What exactly do they mean by single photons? They're not talking one at a time are they? Probably a simple answer but wording like this starts my layman's wheels spinning.
I think so.Aren't the interference patterns in the double slit experiment built up one photon at a time?

Those Hubble photons would all be different I would say.

46. Aren't the interference patterns in the double slit experiment built up one photon at a time?
I think that's what the educational videos report/show.

Laymen are probably prone to making more assumptions about science than the scientists themselves. Just typed in Google Search...'can a single photon contain an image' and found this

https://www.theregister.co.uk/2007/0...hoton_storage/

Not sure if what they're saying is going to get me to jump to a conclusion or whether I misread it completely. Just looking at the article would probably be enough to convince me that a galaxy revealed in the Hubble Deep Field pic consists of one photon, but I'm probably wrong.

47. Originally Posted by zinjanthropos
Aren't the interference patterns in the double slit experiment built up one photon at a time?
I think that's what the educational videos report/show.

Laymen are probably prone to making more assumptions about science than the scientists themselves. Just typed in Google Search...'can a single photon contain an image' and found this

https://www.theregister.co.uk/2007/0...hoton_storage/

Not sure if what they're saying is going to get me to jump to a conclusion or whether I misread it completely. Just looking at the article would probably be enough to convince me that a galaxy revealed in the Hubble Deep Field pic consists of one photon, but I'm probably wrong.
Did you see the Scientific American link at the bottom of that page?

https://www.scientificamerican.com/a...ngle-photon-p/

48. Did you see the Scientific American link at the bottom of that page?
Nope. What did I tell ya? Wrong again

Just how many photons does it take for an image of billions of galaxies in the vast reaches of space? Is the answer ....all of them. Or is Hubble only picking up some and a computer fills in for what's missing?

Edit: checked out physics forum. Objects appear small because they subtend to a smaller angle.
Subtend:(of a line, arc, or figure) form (an angle) at a particular point when straight lines from its extremities are joined at that point.

However not all the photons get to you lest the eyes be incinerated and you go blind. So the photons are focused to a point and be grateful your eyes are curved. If flat, the sky would be unbelievably bright. Distance would not affect the image size . Can't imagine a sky like that.

Is anything as it seems?
I spend my whole life observing a smaller version of things ( Good news for the less endowed). The further away I get from an object the less photons I see emanating from it.

The point of focused light we see apparently represents only some fraction of all the photons that the object emits. As a sidebar: How in hell do we measure anything accurately?

49. Originally Posted by zinjanthropos
Did you see the Scientific American link at the bottom of that page?
Nope. What did I tell ya? Wrong again

Just how many photons does it take for an image of billions of galaxies in the vast reaches of space? Is the answer ....all of them. Or is Hubble only picking up some and a computer fills in for what's missing?

Edit: checked out physics forum. Objects appear small because they subtend to a smaller angle.
Subtend:(of a line, arc, or figure) form (an angle) at a particular point when straight lines from its extremities are joined at that point.

However not all the photons get to you lest the eyes be incinerated and you go blind. So the photons are focused to a point and be grateful your eyes are curved. If flat, the sky would be unbelievably bright. Distance would not affect the image size . Can't imagine a sky like that.

Is anything as it seems?
I spend my whole life observing a smaller version of things ( Good news for the less endowed). The further away I get from an object the less photons I see emanating from it.

The point of focused light we see apparently represents only some fraction of all the photons that the object emits. As a sidebar: How in hell do we measure anything accurately?

My answer is n billion photons at a minimum to capture n billion galaxies - with greater than n billion photons allowing for higher definition.

"Accurately" is relative unless you are looking for complete accuracy which is a priori unattainable.

50. My answer is n billion photons at a minimum to capture n billion galaxies - with greater than n billion photons allowing for higher definition.
Works for me. What an amazing little apparatus we are, complete with HD receiver.

"Accurately" is relative unless you are looking for complete accuracy which is a priori unattainable.
I feel like we've touched on the Uncertainty Principle here

Meh....made for an interesting day

51. Originally Posted by zinjanthropos

I feel like we've touched on the Uncertainty Principle here
I thought so too, but probably the UP is more tied down. Doesn't it just say you can have location to any degree of accuracy but your momentum is lost proportionately?

52. Originally Posted by geordief
Originally Posted by zinjanthropos

I feel like we've touched on the Uncertainty Principle here
I thought so too, but probably the UP is more tied down. Doesn't it just say you can have location to any degree of accuracy but your momentum is lost proportionately?
Something like that. I'm just more amazed that what we observe is never the whole enchilada nor the true size. But I don't know if my eyes could ever absorb every photon an object emits.

53.

54. Thanks for the link GE. What I was thinking when geo and I were chatting was this..... if i put a ruler on a sheet of paper with a straight line printed on it ,how can I measure line's length accurately? I figure it can't be done because the ruler and the line are different distances from me. The increment marks on the ruler are just that little bit narrower because of the subtended angle I view the photons from them. The line also gets shorter for same reason and it's not even on the same plane as the ruler I believe. But what do I know

55. The existential dimensions(sizes) of the objects in question are subject to uncertainty.
https://en.m.wikipedia.org/wiki/Matter_wave

56. With all the motion, bumping and grinding a particle with mass goes through over the aeons, what are the odds of any two of them being the same age or are they all the same age, as seen from my/your perspective? I would think everyone of them moves into the future at varying rates over time.

57. Originally Posted by zinjanthropos
With all the motion, bumping and grinding a particle with mass goes through over the aeons, what are the odds of any two of them being the same age or are they all the same age, as seen from my/your perspective? I would think everyone of them moves into the future at varying rates over time.
I think they all move into the future at the same rate (1 sec per sec in Mangledese)

Only from a different frame do they seem to age differently (so I have gathered)

I think though that "particle" might be different from "object"

58. Originally Posted by geordief
Originally Posted by zinjanthropos
With all the motion, bumping and grinding a particle with mass goes through over the aeons, what are the odds of any two of them being the same age or are they all the same age, as seen from my/your perspective? I would think everyone of them moves into the future at varying rates over time.
I think they all move into the future at the same rate (1 sec per sec in Mangledese)

Only from a different frame do they seem to age differently (so I have gathered)

I think though that "particle" might be different from "object"
I was only thinking this because I was wondering if the Uncertainty Principle could be applied to time as well.

59. Originally Posted by zinjanthropos
Originally Posted by geordief
Originally Posted by zinjanthropos
With all the motion, bumping and grinding a particle with mass goes through over the aeons, what are the odds of any two of them being the same age or are they all the same age, as seen from my/your perspective? I would think everyone of them moves into the future at varying rates over time.
I think they all move into the future at the same rate (1 sec per sec in Mangledese)

Only from a different frame do they seem to age differently (so I have gathered)

I think though that "particle" might be different from "object"
I was only thinking this because I was wondering if the Uncertainty Principle could be applied to time as well.
Location requires a time measurement,doesn't it?(as does momentum)

I don't think "time itself" is a helpful definition (not that you brought it up)

60. Location requires a time measurement,doesn't it?
My thinking is that for a 1, 2 or 3D particle, there is no definitive single place in time because the particle possesses at least one spatial dimension. Does a single time coordinate cover the entire length, width or depth of a particle? For this reason perhaps, the location in time for a particle with at least one spatial dimension is an uncertainty. But I've been wrong before. These mental gymnastics are wearing me out.

61. Originally Posted by zinjanthropos
Location requires a time measurement,doesn't it?
My thinking is that for a 1, 2 or 3D particle, there is no definitive single place in time because the particle possesses at least one spatial dimension. Does a single time coordinate cover the entire length, width or depth of a particle? For this reason perhaps, the location in time for a particle with at least one spatial dimension is an uncertainty. But I've been wrong before. These mental gymnastics are wearing me out.
Have you heard that particles are an excitation in a field?

Maybe the particle would have to share the (same) dimensionality of the field it was attached to.I am just talking off the top of my head ....

62. Originally Posted by geordief
Have you heard that particles are an excitation in a field?
I have heard but I like the word particle...less typing.

I'm thinking a zero point dimensionless particle has a time coordinate.

63. Originally Posted by zinjanthropos

I'm thinking a zero point dimensionless particle has a time coordinate.
Why do you think that if its location is only as accurate as its momentum is inaccurate?

Won't its time coordinates also lie along a corresponding window of values?

(and these time coordinates also have to be as measured from a particular frame of reference,don't they?)

I don't understand point particles ,so I may be "talking across" you.

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