A question on photons and volume

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Re: A question on photons and volume

#21  Postby laklak » Jul 04, 2018 3:16 pm

Just compare us to the competition with this simple Double Slit Test! Their product leaves your light lumpy, but with ours your light is wavy and full!
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Re: A question on photons and volume

#22  Postby newolder » Jul 04, 2018 3:20 pm

Cito di Pense wrote:Plus, my Feynman diagrams have too many squiggly things in them. I need to have them straightened, so my light can pass for white.

A liberal course of the amplituhedron volumator should distangle your worries away...
Perturbative scattering amplitudes in gauge theories have remarkable simplicity and hidden infinite dimensional symmetries that are completely obscured in the conventional formulation of field theory using Feynman diagrams. This suggests the existence of a new understanding for scattering amplitudes where locality and unitarity do not play a central role but are derived consequences from a different starting point. In this note we provide such an understanding for N=4 SYM scattering amplitudes in the planar limit, which we identify as "the volume" of a new mathematical object--the Amplituhedron--generalizing the positive Grassmannian. Locality and unitarity emerge hand-in-hand from positive geometry.
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Re: A question on photons and volume

#23  Postby DavidMcC » Jul 05, 2018 7:24 pm

Thomas Eshuis wrote:
DavidMcC wrote:
newolder wrote:What insult, DavidMcC? I've read elsewhere that you display the characteristics of some kind of persecution complex but this is the first time I can recall I've seen it displayed openly.

That's your interpretation. You have to bear in mind your own issues. I suspect that, for years, you have been waiting for a chance to hit back after I exposed your FTL travel nonsense as just that.

You really believe the entire universe revolves around you and your pet hypotheses don't you? :roll:

:roll:
Your issue is you can't seem to post anything on-topic. This is the physics forum, not the post BS at David forum,OK?

.
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Re: A question on photons and volume

#24  Postby Thomas Eshuis » Jul 05, 2018 8:17 pm

DavidMcC wrote:
Thomas Eshuis wrote:
DavidMcC wrote:
newolder wrote:What insult, DavidMcC? I've read elsewhere that you display the characteristics of some kind of persecution complex but this is the first time I can recall I've seen it displayed openly.

That's your interpretation. You have to bear in mind your own issues. I suspect that, for years, you have been waiting for a chance to hit back after I exposed your FTL travel nonsense as just that.

You really believe the entire universe revolves around you and your pet hypotheses don't you? :roll:

:roll:
Your issue is you can't seem to post anything on-topic.

Don't project your own issues onto me David. It won't fool anyone and only serve to prove my point.

DavidMcC wrote: This is the physics forum, not the post BS at David forum,OK?

.

You're in no position to lecture people about off-topic posting as long as you keep making baseless and off-topic accusations about people who don't kow-tow to your baseless claims.
"Respect for personal beliefs = "I am going to tell you all what I think of YOU, but don't dare retort and tell what you think of ME because...it's my personal belief". Hmm. A bully's charter and no mistake."
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Re: A question on photons and volume

#25  Postby Cito di Pense » Jul 06, 2018 7:41 am

DavidMcC wrote:This is the physics forum, not the post BS at David forum,OK?


If it is, post some physics, instead of sepulchral pronouncements, such as:

DavidMcC wrote:...there is no specific volume associated with a photon in the first place.
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Re: A question on photons and volume

#26  Postby DavidMcC » Jul 07, 2018 5:13 pm

Cito di Pense wrote:
DavidMcC wrote:This is the physics forum, not the post BS at David forum,OK?


If it is, post some physics, instead of sepulchral pronouncements, such as:

DavidMcC wrote:...there is no specific volume associated with a photon in the first place.

I was, because what I said is correct, "sepulchral" or not. PS, please translate sepulchral into a meanigful physics term.
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Re: A question on photons and volume

#27  Postby DavidMcC » Jul 07, 2018 5:14 pm

Thomas Eshuis wrote:
DavidMcC wrote:
Thomas Eshuis wrote:
DavidMcC wrote:
That's your interpretation. You have to bear in mind your own issues. I suspect that, for years, you have been waiting for a chance to hit back after I exposed your FTL travel nonsense as just that.

You really believe the entire universe revolves around you and your pet hypotheses don't you? :roll:

:roll:
Your issue is you can't seem to post anything on-topic.

Don't project your own issues onto me David. It won't fool anyone and only serve to prove my point.

DavidMcC wrote: This is the physics forum, not the post BS at David forum,OK?

.

You're in no position to lecture people about off-topic posting as long as you keep making baseless and off-topic accusations about people who don't kow-tow to your baseless claims.

..

(Again, you're not worth responding to - no physics content, as usual.)
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Re: A question on photons and volume

#28  Postby newolder » Jul 07, 2018 5:32 pm

DavidMcC wrote:
Cito di Pense wrote:
DavidMcC wrote:This is the physics forum, not the post BS at David forum,OK?


If it is, post some physics, instead of sepulchral pronouncements, such as:

DavidMcC wrote:...there is no specific volume associated with a photon in the first place.

I was, because what I said is correct, "sepulchral" or not. PS, please translate sepulchral into a meanigful physics term.

From my own pit of questions, could you translate "photon" into meaningful physics terms and describe how a single "photon" in a double slit experiment gets to its final position on the screen? :ask:
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Re: A question on photons and volume

#29  Postby scott1328 » Jul 07, 2018 11:30 pm

newolder wrote:
DavidMcC wrote:
Cito di Pense wrote:
DavidMcC wrote:This is the physics forum, not the post BS at David forum,OK?


If it is, post some physics, instead of sepulchral pronouncements, such as:

DavidMcC wrote:...there is no specific volume associated with a photon in the first place.

I was, because what I said is correct, "sepulchral" or not. PS, please translate sepulchral into a meanigful physics term.

From my own pit of questions, could you translate "photon" into meaningful physics terms and describe how a single "photon" in a double slit experiment gets to its final position on the screen? :ask:

In every way possible? :ask:
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Re: A question on photons and volume

#30  Postby laklak » Jul 08, 2018 3:46 am

Two photons, close-coupled at start,
Flew several parsecs apart.
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Re: A question on photons and volume

#31  Postby Thomas Eshuis » Jul 08, 2018 8:17 am

DavidMcC wrote:
Thomas Eshuis wrote:
DavidMcC wrote:
Thomas Eshuis wrote:
You really believe the entire universe revolves around you and your pet hypotheses don't you? :roll:

:roll:
Your issue is you can't seem to post anything on-topic.

Don't project your own issues onto me David. It won't fool anyone and only serve to prove my point.

DavidMcC wrote: This is the physics forum, not the post BS at David forum,OK?

.

You're in no position to lecture people about off-topic posting as long as you keep making baseless and off-topic accusations about people who don't kow-tow to your baseless claims.

..

(Again, you're not worth responding to - no physics content, as usual.)

1. You're contradicting yourself by posting that statement.
2. You continue to demonstrate hypocricy by lecturing others about the very off-topic posting you yourself engage in.
3. You fail to refute the points being raised.
"Respect for personal beliefs = "I am going to tell you all what I think of YOU, but don't dare retort and tell what you think of ME because...it's my personal belief". Hmm. A bully's charter and no mistake."
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Re: A question on photons and volume

#32  Postby twistor59 » Jul 08, 2018 10:34 am

It's not a classical object so you can't really define its volume in the usual way, but you can define something which is sort of volumey.

Perhaps the best approximation to measuring a volume of a photon is to prepare many instances of a give single photon state, and measure which locations in space it's detected at and with which probability. It's fraught with challenges, since you don't know the exact emission time etc, but it would give a probabilistic measure of a "volume".

The best way to understand photons is to read this book:
https://www.amazon.co.uk/Introduction-Quantum-Optics-Quanta-Teleportation/dp/0521835631

It has some maths in it, but not too much, and it explains things very well indeed. It's one of my favourite physics books which I wish I'd had as a student.
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Re: A question on photons and volume

#33  Postby newolder » Jul 08, 2018 10:51 am

^ Is this because (essentially) the Lorentz/Fitzgerald contraction to 0 along the propagation axis is extended to non-zero thickness by Heisenberg Uncertainty effects?
Last edited by newolder on Jul 08, 2018 11:02 am, edited 1 time in total.
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Re: A question on photons and volume

#34  Postby DavidMcC » Jul 08, 2018 10:57 am

twistor59 wrote:It's not a classical object so you can't really define its volume in the usual way, but you can define something which is sort of volumey.

Perhaps the best approximation to measuring a volume of a photon is to prepare many instances of a give single photon state, and measure which locations in space it's detected at and with which probability. It's fraught with challenges, since you don't know the exact emission time etc, but it would give a probabilistic measure of a "volume".

The best way to understand photons is to read this book:
https://www.amazon.co.uk/Introduction-Quantum-Optics-Quanta-Teleportation/dp/0521835631

It has some maths in it, but not too much, and it explains things very well indeed. It's one of my favourite physics books which I wish I'd had as a student.

Thanks for discussing the actual topic, twistor59 (unlike cerain other posters), and I certainly agree that the subject is fraught with problems!
What does Harry Paul mean by "teleportation" in this context? (I haven't read the book.)
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Re: A question on photons and volume

#35  Postby Thomas Eshuis » Jul 08, 2018 11:12 am

DavidMcC wrote:
twistor59 wrote:It's not a classical object so you can't really define its volume in the usual way, but you can define something which is sort of volumey.

Perhaps the best approximation to measuring a volume of a photon is to prepare many instances of a give single photon state, and measure which locations in space it's detected at and with which probability. It's fraught with challenges, since you don't know the exact emission time etc, but it would give a probabilistic measure of a "volume".

The best way to understand photons is to read this book:
https://www.amazon.co.uk/Introduction-Quantum-Optics-Quanta-Teleportation/dp/0521835631

It has some maths in it, but not too much, and it explains things very well indeed. It's one of my favourite physics books which I wish I'd had as a student.

Thanks for discussing the actual topic, twistor59 (unlike cerain other posters),

QED more hypocricy.
Look at the plank in your own eye David.
"Respect for personal beliefs = "I am going to tell you all what I think of YOU, but don't dare retort and tell what you think of ME because...it's my personal belief". Hmm. A bully's charter and no mistake."
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Re: A question on photons and volume

#36  Postby DavidMcC » Jul 08, 2018 11:23 am

..

More tired old, off-topic attempts at provocation, I see. It won't work, OK?
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Re: A question on photons and volume

#37  Postby Thomas Eshuis » Jul 08, 2018 11:32 am

DavidMcC wrote:..

More tired old, off-topic attempts at provocation, I see. It won't work, OK?

:lol:
You really love to contradict yourself don't you?
By all means do continue to prove my point whilst dodging on topic questions made by other members.
"Respect for personal beliefs = "I am going to tell you all what I think of YOU, but don't dare retort and tell what you think of ME because...it's my personal belief". Hmm. A bully's charter and no mistake."
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Re: A question on photons and volume

#38  Postby DavidMcC » Jul 08, 2018 12:12 pm

Yet another of your general purpose insult posts, that can be used anywhere you like. Are you sure you're not a bot?
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Re: A question on photons and volume

#39  Postby Thomas Eshuis » Jul 08, 2018 12:13 pm

DavidMcC wrote:Yet another of your general purpose insult posts,

Yet another of your blind, counterfactual and more importantly, off-topic accusations. :lol:

DavidMcC wrote:Are you sure you're not a bot?

Have you stopped beating your wife? :roll:
"Respect for personal beliefs = "I am going to tell you all what I think of YOU, but don't dare retort and tell what you think of ME because...it's my personal belief". Hmm. A bully's charter and no mistake."
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Re: A question on photons and volume

#40  Postby DavidMcC » Jul 08, 2018 12:25 pm

..

EDIT: If you have nothing useful to contribute to a thread, I suggest that you don't post in it, rather than using your standard, use anywhere, insults.
Last edited by DavidMcC on Jul 08, 2018 12:37 pm, edited 1 time in total.
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