# A Matter of Relativity?

### Part 4: Photons that hit tilted glass

Individual photons directed at tilted glass have an option of being reflected or going through. They can’t do both because they can’t be divided, or so we are told. Yet some experiments seem to imply that they sometimes take both paths unless a detector is in place. It is my thought that the foreshortened world of the photon explains this phenomenon too

## Relativity at Work

Because the photon is moving at the speed of light, the entire path from emission to destruction has zero length and zero time passage.   Time and space are both warped while it is in flight.   It does not matter what we measure or calculate.   The entire experimental assembly is to the photon like a flat surface with all the options congruent to the front surface, that surface being stuck to the point of its emission, and shrunk to zero thickness, glass, air paths, mirrors and all. All the open paths are the same length (zero) to the photon, regardless of how we measure them.

If a detector is in place, it is in the way immediately, independently of distances and times as we measure them. The photon is instantaneously (from a relativistic perspective) connected to the screen by all optional paths that lead to the same points, and the photon separates without breaking until it begins to meld together somewhere. Otherwise it takes one path or another and still gets where it is going.

There is an argument that the photon must go through the glass whole since the photons transmitted through the glass are actually retransmissions within the glass, not the same photon that impacts it. That argument then says that the other path has to either have had no photon or a whole one also (creation of energy not allowed). It also says that the photon must retain a whole packet of energy.

My argument is that the entire path, including the glass and the remaining path through the experiment all the way to a recombination point is impossibly thin to the photon at the time it hits it.   There is no separation because the paths are zero distance apart.  This argument also avoids the messy retransmissions within the glass argument, as they are not necessary.

It can then “feel’ itself through this very thin apparatus. It is thus capable of separating into two paths that recombine at the proper point before the photon separates at the surface of the glass. This keeps the photon whole and yet allows it to take multiple paths.

Our perspective seems to be that the flight path is of finite duration and the paths seem to be of vastly different lengths. Thus we don’t always understand what is happening. The photon could care less about our perspective – it is working within a highly warped time and space and we are not.  If it finds a way to recombine without violating its energy conservation directive, it will do so even if a portion of it separates at the glass, wraps around the various mirrors and recombines with a portion that is passing through the glass. That is ok since the total distance of its flat world is still zero and the physical recombination takes place before the physical separation takes place.  United they move!

The experimental apparatus grows as the photon passes through it.  Those parts in front of the photon are still stuck to its nose and of zero remaining depth.  Those parts to each side of the photon have normal depth and structure.  Those it has passed are invisible and forever behind it, vanished.   When it hits a glass surface, all the paths in front of and also along its reflected paths are plastered as if congruent.  Thus all open paths are available at that instant.  If any are closed, then those paths are not available for passage.

Even where a detector is switched in (from our perspective) after it passes through the glass, it is a closed path to the photon at the glass surface because the entire path has zero depth the instant it is emitted due to the photon being at c throughout its entire path.   Indeed the path with the detector is closed when it is emitted, as all the paths are of zero depth the instant emitted, even if the photon is switched in at some later time (from our perspective).   Relativistic foreshortening is instantaneous to an object running at c.  This is all taking place in a space-time warp where length is zero, time is zero for the photon’s flight but not for us, the stationary observers!

The difficult thing to wrap our minds around is the fact that the instant the photon is emitted, whether on a distant star, or on a filiment within our laboratory, the entire path that it takes occurs at the same instant of time throughout its path, birth, flight, death – all instantaneous to the photon (no matter what happens within that path in our “normal world” time-frame) .   If a detector is absent at the instant the photon is emitted and then switched in later before it arrives (from our normal world perspective), the photon is fully affected at the instant of emission (from a relativistic world perspective) as if it had been there the whole time, and thus the outcome is determined at that instant, not when we think it has passed.   It cannot be fooled.

## It is all a matter of relativity

### 4 responses to “Quantum Weirdness – A Matter of Relativity? Part 4”

1. Jim Hughes

Set up a science fair experiment 2 years ago with my son. Diode laser directed 45′ through a polarized lens. A second polarized lens behind the first was rotated thru 180′. When initial measurements were done with a crude photometer, the luminocity of the reflected light was diminished when the second lens was oriented 45′ relative to the first. When more accurated measurements were attempted, the affected was not present. Irrespective of the experimental setup, this got me thinking. Are there times when more accurate measurements actualy obscure scientific results, ie are there times when “squinting you eyes” helps you “see” an event more clearly.
Thanks for you imput.

2. There actually is a Heisenberg’s Uncertainty Principle in which the more accurately you measure one parameter (such as location) then the less accurately you can measure another parameter (such as momentum). So if you squint at one, the other is, in fact, more clearly seen.

In the case you cited, I think the accuracy limitations on high school equipment may be too great to observe the uncertainty principle at work (although there are high school setups capable of this observation). It is very likely that some undetected mistake in setup was made. Excellent thought though, and right on the mark!

Oldtimer

3. Wayne Young

Love this stuff thanks.
Light, is a form of EM propagation. It’s wavelength, spin, and polarization are all attributes which vary.
Although I can choose to assume that to the photon the relative time it takes to travel is instantaneous and the length it perceives to have traveled is zero; doesn’t the fact that its existence which depends on these time dependant attributes introduce a quantative variable which prohibits a non zero analysis of time.
The red photons from my monitor due to my spelling mistakes reach my eye after about 10^6 oscillations, the same color light that my telescope picks up from Betelgeuse has closer to 10^25 oscillations before my eye can perceive it.
In my example, how do you reconcile a time-zero, distance-zero existence for all photons if a time and distance variable (frequency or spin) must exist in order for the quantum entity to exist, and the photons experience an existence (measured in oscillations) which are, like light as perceived in our non relativist viewpoint, to be 10 billion-billion times greater in number?

4. Wayne, you asked such an excellent question, thanks.

I believe that all EM propagation is made up of photons, and any EM can exhibit individual photons when reduced to its smallest values — just keep turning it down and an individual photon is emitted.

Photons emitted by transmitters, whether radio, microwave or light are usually emitted by (perhaps modulated) coherent signals in massive numbers of photons. It is the modulation that we detect as signal.

Individual photons within that signal, however, have their own energy, spin and polarization when emitted but those spins and polarizations and even “phase” do not change during filght, unless it encounters something physical, such as air or water or glass (or even virtual particles) which disturb it in some way.

“Wavelength” from various sources varies due to when the photons are emitted (how far apart), as does phase and polarization, but not within an individual photon within that signal.

Wavelength does not even matter to an individual photon except by convention, as a function of its energy and the charateristic effect of that energy when it hits something.

Most signals used for light experiments are coherent. That means indivicual photons are in lock step with each other and have the same phase, etc. Wavelength of an individual photon is expressed as a function of its energy. All photons of the same energy have the same wavelength, and it does not change within the photon.

Photons live two lives – the one that we can perceive and measure from our frame of reference and one that the photon experiences within its own.

Photons in flight were initially emitted at a particular spin, phase, polarization, energy, etc. but none of these move a muscle during flight as it has no internal time to do so. To the photon the entire flight is instantaneous, whether from that screen of yours or from across the universe. Its parts don’t move even physically.

We, on the other hand, can measure or calculate its speed and time of flight based on the knowledge that it is traveling at c. We can devise experiments to prove it.

However its “wavelength” and corresponding “frequency” are a function of its energy and is expressed only when it is disturbed by a close encounter with a slit, or hits a rod in your eye, or blasts electrons off of a sensor, tries to make its way through glass, or bangs into another particle, (etc.). The photon may very momentarily “ring” when such an event occurs. Who knows? If it does, it does so due to the energy packet being disturbed and is a characteristic of its energy and not because it is oscillating during flight, and the ringing ends when it bounces off or moves on at c.

So it is my opinion that the 10^6 oscilations you are counting are not real, that a photon does not really osciallate during its flight, that its phase does not change, nor its spin, nor its polarization unless disturbed. We can calculate an *individual* photon’s oscillations but not measure them. We can develop charts or see rainbows but only for photons that have hit something and been deflected or bent, not when they are actually moving. We apply that characteristic based on its energy and how that affects its travel through various mediums or how it affects the rods in our eyes or our other energy measuring devices.

So, in summary, the photons exist as a moving energy packet that internally is not moving, not oscillating, not changing phase, but zipping along a maximally warped line that appears to have zero length to the photon, but measurable length from our side of the event, a measurable energy packet only when it encounters something else that bends, destroys or slows it down, and those bends, energy releases, or reduced speed are proportional to a scale that we relate to as oscillations.

As a slight clarification: The wavelength as a length measurement may actually be real, associated with the size of the energy packet somehow, but the oscillations are not since nothing moves, a feature required by the word “oscillation”, but not required by the word “wavelength” unless you break it down into two words.

I hope at least some of that makes sense and some of it turns out to be right.

Oldtimer