Photon Propagation : Straightline or Helix ?

The photons propagate in a straight line although their combined paths follow a helix.
Every photon will follow the straightest path possible in curved/warped twisted spacetime. That is all this argument is about. The god is playing games and has already been warned.......
In Special Relativity (SR), all free particles, including photons, propagate in straight lines governed by
$$E^2 = (m c^2)^2 + (c \vec{p} )^2 , \; E \vec{v} = c^2 \vec{p}$$
so conservation of $$E$$ and $$\vec{p}$$ for an isolated system (such as a free particle) guarantees constant $$\vec{v}$$ so the equation of motion is a straight line.

In General Relativity (GR), all free particles, including photons, propagate in straightest possible lines in the curved geometry of a space-time manifold governed by
$$\mathbf{p}^2 = m, \; \mathbf{\nabla}_{\mathbf{p}} \mathbf{p} = 0$$.


[Moderator: The God is asked to respond with lengthier and better supported explanations of his reasoning, theoretical and factual basis before continuing. The God is suspected of arguing unfairly not explaining his preconceptions and/or setting up a trap and moving the goal posts when someone responds to the bait. Either would be trolling, which is forbidden by forum rules, so it is to The God's benefit to explain his position better and more fairly to his readers.]
 
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It's obvious where you are coming from as being one who has rejected/dismissed/doubts the BB in past debates.
Again, Citation needed paddoboy.

Please provide "quoted" passages from Posts Authored by me that support your ^^above quoted^^ Ad Hominem assertion.
 
Reference? A geodesic is most certainly the shortest distance between two points on a curved surface.
https://www.google.com.au/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=what+is+a+geodesic+
geodesic
ˌdʒiːə(ʊ)ˈdɛsɪk,-ˈdiːsɪk/
adjective
adjective: geodesic
  1. 1.
    relating to or denoting the shortest possible line between two points on a sphere or other curved surface.
    • (of a dome or other structure) constructed from struts which follow geodesic lines and typically form an open framework of triangles and polygons.
http://www.dictionary.com/browse/geodesic
geodesic
1.
Also, geodesical. pertaining to the geometry of curved surfaces, inwhich geodesic lines take the place of the straight lines of planegeometry.

http://mathworld.wolfram.com/Geodesic.html

Thats why I said lack of understanding !

Take a bigger circle on the surface of the earth.....From point A to point B on this circle (say these points are not diametrically opposite, hope you understand that)...then AB can be traversed, either on the shorter path or on the longer path. Now can you say that the longer path is not the geodesic ? Just visualise and respond...do not just do blind copy paste.
 
In the following image all photons propagate in a straight line at c from their rotating sources to the observer. Were the observer to stay absolutely stationary wrt the center of mass of the rotating sources, the sources continued to emit photons during one complete rotation and there is nothing that distorts or blocks the in transit photons, all the photons shown would arrive at the observer during the next complete rotation. Were the observer to move after the observation these paths would still exist at the time of the observation.

This isn't a geodesic, the space is Euclidean and these photon paths exist between the source(s) and observer in real time at the time of the observation.

The photons propagate in a straight line although their combined paths follow a helix.

Rotations%20shift%20three.jpg

Good one !

But the GR definition of straightline line makes you accept even the helical locus as straightline....well, thats how it is ? There was absolutely no need to do so...they could have termed this as something else.

As I have written earlier, in flat spacetime, an accelerated particle can traverse the straightline....even though definition will call it as non straightline...

Moreover any path having larger curvature than the photons, can be traversed under suitable external force...so the definition of straightline needs recalibration. IMO the path followed by the light bwetween two points should be termed as straightline, anything else shall be non-straightline. Take for example, two points A and B, in flat spacetime the photon can traverse A and B like Euclidean straightline (least geomterical path), but in curved space time A and B cannot be covered by photon by least geomterical path, so the photon path must be a concave (dome shape) path....that should be the straightline. Any path having lesser curvature is ruled out, and any path having larger curvature should be non straightline curve.......I see it most logical and reasonable definition.
 
Again, Citation needed paddoboy.
Please provide "quoted" passages from Posts Authored by me that support your ^^above quoted^^ Ad Hominem assertion.
Are you denying you said it?
If so, once again, welcome to the logic and reasonability of the scientific method and peer review. Glad you do approve, at least that's a starting point.
 
Thats why I said lack of understanding !

Take a bigger circle on the surface of the earth.....From point A to point B on this circle (say these points are not diametrically opposite, hope you understand that)...then AB can be traversed, either on the shorter path or on the longer path. Now can you say that the longer path is not the geodesic ? Just visualise and respond...do not just do blind copy paste.
They are both geodesics.....
What were you saying about understanding?
[Moderator: The God is asked to respond with lengthier and better supported explanations of his reasoning, theoretical and factual basis before continuing. The God is suspected of arguing unfairly not explaining his preconceptions and/or setting up a trap and moving the goal posts when someone responds to the bait. Either would be trolling, which is forbidden by forum rules, so it is to The God's benefit to explain his position better and more fairly to his readers.]
 
Good one !
As I have written earlier,

Yes, you write much on cosmology none of it credible...None of it supported by either a mathematical construct or any reputable reference.
Just your say so.
:rolleyes:
Every photon will follow the straightest path possible in curved/warped twisted spacetime. Which obviously is the shortest.
 
Paddoboy,

You are incorrigible...

You admit that longer arc AB is also geodesic, and still in the very next post you say that geodesic is the shortest.
This is trolling and foolishness coupled with that.

And you have quoted this Rpenner red post 3 times, does that make your stand better ? You want to win a point by telling me that Rpenner questioned me or my threads were consigned to cesspool or I have anti mainstream agenda....is that your argument ?
 
Just visualise and respond...do not just do blind copy paste.
Your obvious dislike for cut n pastes is understandable...You have the same dislike for reputable E-Mails invalidating your rather precarious position re cosmology.
Of course they will continue if and when I find necessary and see fit.
Your question is really so easy to answer, I'm rather astounded that you think it somehow invalidates the concept that a geodesic is the shortest possible path.
Photons of course are emitted with momentum...you understand that?
Obviously the direction that momentum is in will be the geodesic taken. No other recourse is possible.
 
Paddoboy,

You are incorrigible...

You admit that longer arc AB is also geodesic, and still in the very next post you say that geodesic is the shortest.
This is trolling and foolishness coupled with that.

And you have quoted this Rpenner red post 3 times, does that make your stand better ? You want to win a point by telling me that Rpenner questioned me or my threads were consigned to cesspool or I have anti mainstream agenda....is that your argument ?
Both paths are geodesics. see previous post.
Better luck on your next endeavour.
ps: When you start acting reasonable and answer questions and supply links to support your nonsense, I'll consider to stop reminding the forum of your threads that have been cesspooled and sent to pseudoscience: Not a good look.
 
Both paths are geodesics. see previous post.
Better luck on your next endeavour.
ps: When you start acting reasonable and answer questions and supply links to support your nonsense, I'll consider to stop reminding the forum of your threads that have been cesspooled and sent to pseudoscience: Not a good look.

Yes right, AB (short) and AB (long) both are geodesics...

So don't ever say that geodesic in curved spacetime is the shortest path; keep learning !!
 
Yes right, AB (short) and AB (long) both are geodesics...

So don't ever say that geodesic in curved spacetime is the shortest path; keep learning !!
Stop obfuscating old friend! Light most certainly travels in geodesics, or the shortest possible path.
Please research the word "possible" Got it?
 
I don't want to play games. I have already stated that everything moves in a straight line through space unless it is acted upon by a force so why are you asking me for an example? You indicated that you had a different thought on this, so what is your thought on this?
If you want to play games I will leave you to have your fun with others that have more patience.
That's the whole point. And why such people need confronting when they are dearly begging for it. Obviously an agenda is at hand, and this has been exposed.
One can "understand" to some extent when a person has a beef against one aspect of cosmology, but when they go from the sublime to the ridiculous, claiming all of cosmology is wrong, claiming reputable experiments are fraudulent, and that they are cosmology's saviour, then people such as this, are using this forum as their vehicle, and I believe they need refuting whenever necessary and at all opportunities.
Sure obviously they are also doing it to get a raise out of people, but sometimes that must be over looked for the better good.
Or that action be taken.
I'm sorry such confrontations upset people.
 
It's obvious where you are coming from as being one who has rejected/dismissed/doubts the BB in past debates.

So...for the third time, paddoboy...
Citation needed.
Please provide "quoted" passages from Posts Authored by me that support your ^^above quoted^^ Ad Hominem assertion.
You have made these spurious allegations that you, twice so far, refuse to support.

Any and all Readers of this Forum are well aware of what you are doing.

By failing to Cite any passages from Posts authored by me, that fully support your allegations, you are tacitly admitting that you are intentionally Posting False statements simply to cast aspersions upon and intended to defame another Member of SciForums.

It's obvious where you are coming from as being one who has rejected/dismissed/doubts the BB in past debates.
So...again...for the third time, paddoboy...
Citation needed.
Please provide "quoted" passages from Posts Authored by me that support your ^^above quoted^^ Ad Hominem assertion.
 
Yes right, AB (short) and AB (long) both are geodesics...

So don't ever say that geodesic in curved spacetime is the shortest path; keep learning !!

Reported for trolling - exactly the kind of nitpicking and deliberate obtuseness I forecast at the start.
 
Yes right, AB (short) and AB (long) both are geodesics...
Incorrect use of singular and plural. For a sphere, they are the same geodesic. For a lumpy Earth there may be more than one "short" route and more than one "long" route in that there may be nearby geodesics from A that diverge because they are headed in different directions but ultimately converge at B. We have space-time examples of this where the gravity of galaxies bends space time so that a single distant quasar can appear as distorted images in four or more nearby places in the sky.
 
be patient-- there are at least a thousand of your post to go through. it is funny, because like i have already mentioned, you know for sure paddoboy's claim is 100% accurate and correct--you just assumed that no one would go through all of the 1k post to do so, but again, i am working on it-- be patient.
 
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