Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Is it possible that light doesn't 'propagate' in a vacuum?

  1. Apr 5, 2004 #1
    I have been thinking again about a Hypothesis that I have been getting together for a while now. I say hypothesis because I don't have enough ability to develop it into something one could call a theory in the mathematical sense of the term. I know people hate that but life doesn't always go to plan.

    The hypothesis has many elements so I am going to break it up into smaller bits that I can get comfortably in my head as reasonable assumptions. Here goes.

    Light does not propagate in a vacuum


    From an experimental point of view, it is impossible to prove categorically that light traverses the space in a vacuum. One can only make assumptions based in the fact that, based on our experience of the behaviour of macro, physical objects that when a 'light particle' is absorbed on the opposite side of a vacuum from the emitter, the most likely scenario is the instinctive one, that the 'particle' followed a trajectory which traverses the space. Fair 'nuf assumption.

    From a theoretical point of view, the 'explore all paths' concept, mathematically suggests that the 'light particle' actually may traverse all possible paths from emitter to absorber. While there would seem to be some debate as to whether this is an actual model of the path taken or purely a mathematical tool, it is the main basis of this first hypothesis.


    The hypothesis is basically that light does not propagate through the vacuuous space (whether it be through a field or otherwise) but that light does literally take all paths, propagating through surrounding matter and 'manifesting' at the absorber point.

    Any thoughts?????

  2. jcsd
  3. Apr 6, 2004 #2
    No theory predicts space or infinity as an absolute vacuum because every force, even vacuum; must have a force carrier. In a vacuum without either force or carrier nothing, including light, can exist; so in that respect you are correct.
  4. Apr 6, 2004 #3
    with an abstraction I would like to respond with

    If there is absolutely nothing between two objects except distance then any emmission would instantaneously be experienced by the other object as there is nothing between the objects for the emmission to transverse therefore the emission is already there.....Nothing being a perfect reversed mirror...what is reflected on one side is reflected on the other ( like a sheet of glass that has no mass.)

    of course this is only an abstraction......
  5. Apr 6, 2004 #4
  6. Apr 6, 2004 #5
    I have an opposite point:
    Nothing can be moved in spacetime except of light.
  7. Apr 6, 2004 #6

    How would any theory based on your postulate explain the fact that light gets from the sun to the earth?

    What is about the presently accepted theory (QED) that has you trying to find a new one? QED accounts very well for every observed phenomenon associated with light propagation, including how light gets from the sun to the earth. It's a tough act to follow!
  8. Apr 6, 2004 #7


    User Avatar

    Staff: Mentor

    What do we have to go on other than the transmitter and detector of the light? Ie, on what could you base the conclusion that light takes "all paths"? The reason we assume light takes the straight path (insert QM caveat) is that we have no information on which to base any other assumption. Lack of data does not give you license to assume anything you want.
  9. Apr 7, 2004 #8
    Just in case you couldn't tell, in the words of a famous philosopher "I have no professional training". I'm just playing around with ideas.

    Mmmm, unfortunately I put the cart before the horse and forgot to mention that the other part of the hypothesis is that the apparent distance between objects in space is purely that, 'apparent distance'. This causes some confusion. Sorry about that. Basically the idea is that all matter/energy occupies the same space and that 'apparent distance' is the result of interaction. Not too implausable I don't think ;)

    It's interesting that, I'm pretty sure it was Feynman, said that if you can't explain it to an average person then you don't actually understand the subject. Reading Feynman's biography, Genius, it would seem that Feynman didn't think that all of his ideas were as beautiful or clean as they could be. Not that the mathematics didn't come out with good answers, but that they weren't simple enough for anyone to understand. I'm certainly not saying that I understand the subject but bits that I have read seem to fit in somewhat with my hairbrain concepts.

    Well that's the thing. Looking at your first question, absolutely nothing. I'm applying the path integrals method here to the path of a 'photon'. I'm not sure if it's normal to do that, but let's say you can. Even looking at the 'vacuum' as not being a vacuum but put what ever you like in it, lets say a field, whatever you'd like to call it. Using the assumption you talked about, lets throw caution to the wind and think about the possiblilities. We cannot detect whether the 'intact photon' is traveling across the vacuum experimentally, but using mathematics we apply our field equations, path integral methods, yadda yadda, to calculate the probability of the photon being in a certain region at a certain time. From these calculations we conclude that tracing these 'probable regions' over time creates a straight line path which coincides with where the photon is absorbed at the opposite side.

    What I am hypothesising, and asking, is it possible that the 'photon information' is contained in the entire field, in reality, not just mathematically, and manifests when it interacts with matter?

    Again to summarise, that the 'light' does not traverse the vacuum but is emmitted at one point and manifested at another point, having 'filled' the entire field, possibly instantaneously.

    Raavin :confused:
  10. Apr 7, 2004 #9

    May be some time in the future your idea will prove to be "in part" correct.

    What you are posing has been bugging me for nearly 12 years and I am sure it is bugging many a better Physicist than I.

    There are many ideas of 2 dimensionality of light and 2 dimensional space etc....the list goes on and on.

    The thing is light has been proved to travel across 3 d space. In fact it is constantly being proved as a par of course as the moons distance is measured on a regular basis

    A 1 second pulse of laser light to the moon and back with a 0.6 second delay in returning and registering for 1 second. ( I think that's the figures )

    So with out any doubt light does travel and in this context is not instantaneous.

    The question I think is really what is the medium that allows it to do so?
  11. Apr 7, 2004 #10
    I'm certainly not refuting anything. It all works out the way it works out. The calculations all seem to work out (to the extent that they are fairly accurate with a bit of uncertainty thrown in). No major problem there. The emission of a photon and the absorption at a 'distance' doesn't happen 'instantantaneously'. It just doesn't. It is bound by 'something' that, using calculations involving relativistic probability, can be fairly accurately predicted. It is...the way it is.

    The question is whether it is at all plausible that, given that experiencing a photon requires that it is emitted and detected by 'matter' that:

    b) the 'field' may be, for want of a better term 'omnipresent'

    c) the 'photon information' may be experienced by the 'entire' field simultaneously

    d) due to the controlling physical laws, the 'photon' may only manifest in the form of a 'reaction' in 'matter' and does not 'exist' as an 'intact photon' in and of itself, in the intervening 'time'.

    Raavin :)
  12. Apr 7, 2004 #11
    Raavin said: "Basically the idea is that all matter/energy occupies the same space and that 'apparent distance' (to the sun) is the result of interaction."

    I don't understand what this means. Does your satement,

    "....'apparent distance' is the result of interaction."

    mean the same thing as,

    interaction causes 'apparent distance'?

    If so, does this imply, since the apparent distance to the moon is 1/4 million miles and the apparent distance to the sun is 93 million miles, that there are two different interactions that cause 1/4 million miles and 93 million miles?

    If so, what's the difference? For that matter, what's the interaction?
  13. Apr 7, 2004 #12
    This is where the other stuff I am thinking about sort of fit's in. My thought is that all 'matter' in the universe exists in a infinitesimal/zero dimensional point as something analogous but not the same as light, in that it can exist in the same physical space, and that 'apparent distance' is created due to interactions of the energy/matter 'waves' as a function of 'time'.

    The 'something' that is light is inextricably connected to the element of the wave function we experience as time which is in turn, inextricably linked to distance, therefore the manifestation of the 'speed' that light, appears constant, in all circumstances.

    In response to your question, the medium (in this vague model) is not a field in 3D space, but 'matter' in infinitesimal/zero dimensional (sub?)space.

    It's my gut feeling (with absolutely no grounding) that one of the confusing elements of physics is the love affair with making things work in 3D space. This is why I asked the question in the manner I did, using fields to cross the 3D 'vacuum'. It confuses things a bit to throw in a doozie.

    It's my understanding, from his biography, that Feynman tried to create a model which just used interactions with no success. It is my rather bold guess, that this tried to take into account traversing a 3D space so didn't work. I'd like to get more info on his efforts in this area, but because it didn't happen I don't know if there would be any papers on it.

    Raavin :biggrin:
  14. Apr 7, 2004 #13
    What vacuum are you discussing:

    The vacuum between particles or the partial vacuum of outer space
  15. Apr 7, 2004 #14
    jdavel said

    "I don't understand what this means. Does your satement,

    "....'apparent distance' is the result of interaction."

    mean the same thing as,

    interaction causes 'apparent distance'?"

    Well...yes. Further on I've tried to explain it a bit more clearly. Not sure how successfully. I'll try with an analogy, probably not a very good one, in fact probably misleading but at the moment this is the best analogy i can think of.

    Lets say we have two globs of matter/energy separated by an arbitrary distance in 3D space. One emits a photon, which, after a given time, is absorbed by the other glob. Us, being a third glob, measure the time between the emmision and absorbtion, applying and allowing for our relativistic calculations and considering the distance between the two globs, the relationship between the distance and time gives a constant 'light speed'.

    Now imagine that the three globs are superimposed on top of each other. They are vibrating away, happily unaware of each other, but are interacting on some level. This interaction manifests as an action, a time delay, and a reaction. Because we use the same mechanism (interaction effects), being the third glob, to take our measurements we apply the same calculations, using our tools (i.e. the experience of reactions/time between the globs) and get exactly the same results.

    In the latter model, the 'transmission' effects are able to be 'felt' by all three simultaneously but the reaction is dependant on the condition (or wave formation) of each glob, as to when the 'photon' will manifest. The manifestation 'time', dictates the apparent distance.

    I'm struggling to explain this accurately.

    Raavin :frown:

    "What vacuum are you discussing:

    The vacuum between particles or the partial vacuum of outer space"

    In this context, one in the same...I think. The lack of 'matter' between particles, whether they be on a quantum or macro level. So not including gravitons or photons or neutrinos or other 'non-matter' conglomerates.

    Last edited: Apr 14, 2004
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook