[yor_on]

Lightarrow, I think I stand by my questions as they are

Give me a clearer description if you want me to see how you think here.
(Although I actually understand what you say about 'excitations'

But if I choose to see photons 'particle-wise' and then question the way they will act if so?
Then that also works as far as I know.
It is not forbidden, is it?

Remember that box you described.
What do that concept make them:)

As for 'infinite', of course not, just an expression used as I questioned it.
What I meant there was, more than I ever would like to enumerate, more than the visible stars etc etc
But you're right, I should be more exact.

But you see it foremost as 'wave patterned' if I get you right.
I still look at it both ways, with an emphasis on 'particles'.
Where you accept all in form of waves and their interactions, i choose to differ, that as I don't see us as 'light' but as foremost 'matter'

That doesn't mean that I don't know, or isn't interested in, that approach too.
But firsthand I'm just trying to find a resolution to my own satisfaction, and so I will walk in the wilderness somewhat more:))

-------

And yes, I think I might know how you might see photons:)
But I'm stubborn son of a ***
Let us take moon light:)

Coming mainly from the sun according to me, reflected by the moon down to me dreamingly thinking about my next BMW (electrical of course:). Traveling at 'c' mostly, (ah, that would be the Suns light traveling, not the BMW:) quite a distance, caressing my loved ones chrome in about ?nine minutes? from where it left the 'surface' of our Sun.

Would you accept my description as being the 'one and only', or might it just be that there could be another description as valid?

[DoctorBeaver (OP)]

LeeE - thank you for clarifying that.

[lightarrow]

Lightarrow, I think I stand by my questions as they are

Give me a clearer description if you want me to see how you think here.
(Although I actually understand what you say about 'excitations'

But if I choose to see photons 'particle-wise' and then question the way they will act if so?
Then that also works as far as I know.
It is not forbidden, is it?

Remember that box you described.
What do that concept make them:)
As for 'infinite', of course not, just an expression used as I questioned it.
What I meant there was, more than I ever would like to enumerate, more than the visible stars etc etc
But you're right, I should be more exact.

But you see it foremost as 'wave patterned' if I get you right.
I still look at it both ways, with an emphasis on 'particles'.
Where you accept all in form of waves and their interactions, i choose to differ, that as I don't see us as 'light' but as foremost 'matter'

That doesn't mean that I don't know, or isn't interested in, that approach too.
But firsthand I'm just trying to find a resolution to my own satisfaction, and so I will walk in the wilderness somewhat more:))

-------

And yes, I think I might know how you might see photons:)
But I'm stubborn son of a ***
Let us take moon light:)

Coming mainly from the sun according to me, reflected by the moon down to me dreamingly thinking about my next BMW (electrical of course:). Traveling at 'c' mostly, (ah, that would be the Suns light traveling, not the BMW:) quite a distance, caressing my loved ones chrome in about ?nine minutes? from where it left the 'surface' of our Sun.

Would you accept my description as being the 'one and only', or might it just be that there could be another description as valid?

Probably I haven't expressed myself very clearly. First of all, I would like to remark the fact that I actually don't know how it really works...I have never seriously studied QED (Quantum Electro Dynamics); it's not an easy subject, for me.
Second, about photon's behaviour, which is very complicated, believe me, many people who think to have understood it, don't, actually.

I also have to precise again that photons cannot be seen uniquely as waves or as particles and so sometimes, as in this case, a complete description requires both aspects, that is, QED. Of course you can consider just the particle-like behaviour, if you prefer (and, of course, it's not forbidden ), but if you are able to understand all of the photon's behaviour with that only, then make me know, because I would really be interested.

"Remember that box you described. What do that concept make them:)"

I'm not a boy anylonger, I'm becoming slow  [] What are you referring at?

About your description of light coming from the Sun and reflecting off the Moon, I don't have anything to say, unless you meant that the same photons which have travelled from the Sun to the Moon are the same who then will travel from the Moon to you (because it's not).

About photons, I'm trying to read this interesting document:
http://stochastix.files.wordpress.com/2008/05/what-is-a-photon.pdf

In one of the articles inside that document, Arthur Zajonc, talking about a book written from Davies, says:
<<Davies uses these and other
problems to argue for a vigorous Copenhagen interpretation
of quantum mechanics that abandons the idea of a “particle as
a really existing thing skipping between measuring devices.”
To my mind, Einstein was right to caution us concerning
light. Our understanding of it has increased enormously in
the 100 years since Planck, but I suspect light will continue to
confound us, while simultaneously luring us to inquire ceaselessly
into its nature.>>

[yor_on]

I agree, they're not the same photons.

Sorry, I was thinking about the way a photon/wave packet 'travel'.
There are some rather advanced ideas about how they might 'move' or rather 'not move', leaning on Feynman, Fourier transformations and 'De Broglie Matter Waves' amongst others.

I wondered if you too was speculating in those 'orbits', so to speak.
I have a good friend and, if I may say so, real gentleman GoodElf whom is a ardent advocate for this view.
Goggle on him if you're interested.
He is very knowledgeable and as I see it a 'foregoer' in his ideas richness.
As for his math I'm sure you're better equipped to understand it than me.
And that goes for some more people here:

I got this feeling that you all here have ideas of your own.
But you are cool about it, and others, which I find to be a matter of taste.
And good taste, to my eyes:)

And thanks for the link..
I live for them:)

[DoctorBeaver (OP)]

I'm lost  []

[yor_on]

Bikerman Isn't it group velocity that enables a phase velocity?
So when 'quenching' group velocity you will 'quench' any information remaining?
Can there exist only a phase velocity??

Or am I misunderstanding you?
Or it??

http://en.wikipedia.org/wiki/Group_velocity

[lightarrow]

I'm lost  []

Where? Ah, yes, if you knew it, you wouldn't be lost... []

[DoctorBeaver (OP)]

I'm lost  []

Where? Ah, yes, if you knew it, you wouldn't be lost... []

I got lost when BEC was mentioned

[lightarrow]

Bikerman Isn't it group velocity that enables a phase velocity?
So when 'quenching' group velocity you will 'quench' any information remaining?
Can there exist only a phase velocity??

Or am I misunderstanding you?
Or it??

http://en.wikipedia.org/wiki/Group_velocity

"Isn't it group velocity that enables a phase velocity?"
This phrase is obscure to me. Do you mean that a single sinusoidal wave cannot exist?
Phase velocity is the speed of a single sinusoidal wave. If there are more than one single wave, then the two or more waves interfere (overlap) producing another shape. This shape travels at a generally different speed (group velocity).

If:

V_ph = phase velocity

V_g = group velocity

ν = frequency of a single wave

ω = 2πν = pulsation but is usually called frequency too

λ = wavelenght of a single wave

k = wavenumber = 2π/λ

then you have:

V_ph = λν = ω/k  -->  ω = kV_ph

V_g = dω(k)/dk

The last formula means: if many frequencies propagates in a medium which, in general, can be "dispersive" = the various frequencies has different phase velocities in it = ω depends on k in a non-linear way (see blu formula), then the derivative dω(k)/dk gives the speed at which the shape of all the packet of waves travels.

Edit. The formula V_g = dω(k)/dk is valid of course even when the medium is not dispersive. In this case V_ph is a constant so V_g = dω(k)/dk = d(kV_ph)/dk = V_ph.
Example: for light in the void, V_g = V_ph = c.

[lightarrow]

I'm lost  []

Where? Ah, yes, if you knew it, you wouldn't be lost... []

I got lost when BEC was mentioned

Bose Einstein Condensate. Is a cloud of extremely cold atoms, prepared and confined specifically, through which light propagates at a cyclist's speed. It's quite similar to the fact light travels at lower than c in glass or water.

[Mr. Scientist]

My answer now, is that you would see it.

I needed some time to think about it. Hard question.

[Bikerman]

Bikerman Isn't it group velocity that enables a phase velocity?
So when 'quenching' group velocity you will 'quench' any information remaining?
Can there exist only a phase velocity??

Or am I misunderstanding you?
Or it??

I was about to compose a length reply but I see that it has already been done above by lightarrow....basically, what he/she said  []

[DoctorBeaver (OP)]

Bikerman Isn't it group velocity that enables a phase velocity?
So when 'quenching' group velocity you will 'quench' any information remaining?
Can there exist only a phase velocity??

Or am I misunderstanding you?
Or it??

I was about to compose a length reply but I see that it has already been done above by lightarrow....basically, what he/she said  []

He. Alberto.

[Bikerman]

Ahh...OK. I normally make a point of not assuming gender on the internet (more out of courtesy than anything else)  []

[DoctorBeaver (OP)]

Ahh...OK. I normally make a point of not assuming gender on the internet (more out of courtesy than anything else)  []

Same here. Unless their pic has a beard like SpeakerToAnimals at ScienceFile   []

[Bikerman]

Ahh...OK. I normally make a point of not assuming gender on the internet (more out of courtesy than anything else)  []

Same here. Unless their pic has a beard like SpeakerToAnimals at ScienceFile   []

LOL...yes, a cunning deception she uses :-)

[DoctorBeaver (OP)]

Ahh...OK. I normally make a point of not assuming gender on the internet (more out of courtesy than anything else)  []

Same here. Unless their pic has a beard like SpeakerToAnimals at ScienceFile   []

LOL...yes, a cunning deception she uses :-)

 [:0]

I saw once that you referred to STA as "she" but I assumed it was a slip of the fingers on your keyboard.

[Bikerman]

Speaker is in fact a she. She describes herself as a 'fat dyke'. She is also, in my opinion, a fabulous teacher and a very clever lady (PhD in particle physics). I have learned a great deal from Speaker and she is one of my favourite internet correspondents.

[DoctorBeaver (OP)]

Gawd! I owe her an apology.

I remember your saying that she had a PhD in particle physics.

[Bikerman]

Gawd! I owe her an apology.

I remember your saying that she had a PhD in particle physics.

It is OK - she often gets mistaken for a 'bloke' and doesn't generally hold a grudge - in fact I think she quite enjoys revealing that she is in fact a large lesbian lady (doesn't half knock the religious bunnies off their stride in debates)