Category Archives: frame of reference

Speed of light regulated

Speed of light regulated

What determines the speed of light? We know that it is a limiting factor for all physical objects. We have heard it time and again – nothing goes faster than c! Nothing.   Can we determine why it is regulated to c?  I think we can.  It is all a matter of relativity.

Photon in FligthSuppose we consider the idea that the photon is disk-shaped due to space distortion.  (See figure at left) The photon is traveling at the speed of light and the space distortion equations tell us that, from our perspective, the photon’s dimensions in the direction of travel are greatly shortened, essentially like a very thin pancake set perpendicular to the direction of travel.

We know that the photon is a ball of energy related to its frequency and we know that the frequency determines the color of light that we can actually detect with our eyes. A blue photon has both a higher frequency and energy than a red photon. All the energy is confined to that flat pancake moving along at the speed of light, c.

Now we come to a slight separation from the earlier argument that the clock of the photon is stopped and nothing wiggles in a photon with a stopped clock. That is, in my opinion, true for the photon, but we are talking about the photon here from an observer’s point of view, not the photon’s perspective.  From the observer’s point of view, the photon moves with measurable velocity, measurable frequency, measurable energy, and thus potentially real live vibrational modes as seen by a clever observer. The time experienced by the photon is still zero from start to finish of its journey, but the observer still knows it is moving at a particular pace and also vibrating as it goes.

The photon cannot vibrate in the front to back direction because to do so implies that the vibration mode that goes toward the back lags behind and then it could never catch up without exceeding the speed of light. This implies that the photon vibrates from side to side or possibly either way around the rim of the disk and never front to back (well, maybe a very little, as explained later). The ripples in the disk are shown greatly magnified in the figure of the photon in flight above. Vertically polarized photons vibrate from rim to rim in a vertical fashion, horizontally polarized vibrate side-to-side and circular polarized photons vibrate around the rim, to and fro, and can even be lopsided a little producing an elliptical polarization.  These types of polarization exist in our real world and we can separate photons with various filters. prisims, and crystals.

Now let us suppose that we consider the vibrational modes of the disk in a little more detail. It seems that any vibration would cause at least some ripples along the disk, and that these ripples must involve at least some bunching of energy producing some motion front to back. Suppose these ripples are constrained to some minimum amplitude in order to even exist.  Could it be that these ripples actually limit the speed of the photon to some factor that actually defines c?   They can.

In other words, if the speed of the photon were to try to increase beyond the speed of light, as seen by our (any) frame of reference, the continuing shortening of the disk would reduce the amplitude of the ripples and potentially slow the photon back down to a speed where the ripples can still exist in our frame of reference. This provides a theory of how the speed of light is established and limited to a particular speed, “the speed of light”, for a photon. The speed of light is about 299,792,458 meters per second, usually symbolized by the letter “c”.

My thought is that when a photon or other particle is emitted, it probably takes off at the highest possible speed that is limited by the speed at which it can still maintain vibrational modes that can exist within an observer’s frame of reference. This is the speed of light as we know it and the regulator is the relativistic shortening of the disk in the direction of travel as seen by the observer. This shortening reduces the amplitude to a point that is sustainable for the energy it contains. If a photon can vibrate longitudinally, it would still be limited in amplitude to the size constrained by the disk in the same way described above, essentially very little, and regulated by the speed. The photon will always go at the maximum speed it can maintain (and no faster) within a given frame of reference. 

Why photons all travel at the same speed 

So why do all photons travel at the same speed?  Even for two observers traveling in differnt directions both measuring the same speed for a photon crusing by?  First lets consider some facts:  Blue light has a frequency, f, entered on 7.88×10^14 HZ and a corresponding energy e of 5.22 10^ -19 Joules. Red light has a frequency centered on 3.79×10^14 HZ and a corresponding energy e of 2.373 x 10^-19 Joules. Since they have different energies and different frequencies, would they not reach that equilibrium at different speeds?

For the answer, consider this:  The energy and frequency of all photons are related to a simple constant, e= hf.   Where h= Planck’s constant= 6.6262*10 ^-34 J s (Joule second).  So the relationship of the energy of photon to its frequency is a constant.

Or put another way, h = e/f for all photons. The ratio of the energy of a photon to its frequency is a constant for all photons. Thus we can see that the sustainable amplitude is somehow related to h and all photons are regulated to the same speed, which we measure as c in any frame of reference.   For example, if you divide the frequency into the energy for the blue and then the red light photons above, the ratio comes out the same.   The result is h, a constant for all photons.   These relationships are well known in the physics world.

However, the frame of reference is a key element, which means that the regulation to c takes place in any frame of reference because the shortening of the disk is related to the speed within the reference of the observer (any observer and all observers), and thus become regulated to c in all frames of reference. If the frame of reference were within a spaceship traveling at near relativistic speed and attempting to measure the speed of a photon going in its direction, the photon’s speed would still be c in respect to the spaceship. The length contraction relative to the spaceship would just be enough to regulate the speed of light measured by the spaceship to agree with the speed observed on earth.

There is a little of cart before the horse-trading going on here. The equations for space distortion and for time dilation both involve the square root of a term that would be a negative number if the photon exceeded the speed of light. In order for us to consider that the photon might even try to go faster than the speed of light, the equation would need some modification to make things right. It might well be that in order for the photon to reach c it might initially slip into “superluminal” speed, but it would quickly be brought back to within the speed bounds by the disk shortening along the path of flight and the reduction of the amplitude of the energy waves in the disk, the shortening taking place in the frame of reference of the measurer/observer.  Even when there are no observers and no measurement taking place, the photon is not alone.  Other particle exist, even in a vaccum, virtual particles for example.  These make up a frame of reference too, so the photon is always locked in to c. 

All photons strive to go faster than c all the time, but are held back by the relativistic effect of space shortening’s effect on the need to vibrate.

This latter discussion begs a new question. If the vibrational modes could somehow be frozen so that they do not need to vibrate in flight as we observe them, could they then travel at an unregulated speed beyond the speed of light? Consider a particle that starts out at absolute zero. In that case all the parts are locked together and nothing moves and therefore has no vibration to sustain. What is to regulate the speed of that particle? Can we then reach superluminal speeds for such a particle?  I don’t think so because to get it up to speed, energy must be applied.  In the case of a photon, the energy comes from the change in states of an electron around an atom or a collision of some sort that generates a photon.  Once we have energy for a massless particle, it has to cruise along at c.

It may be possible that a photon in flight passing thorough from another dimension/universe might have motion relative to us moving so fast that there is no effective vibration taking place during the time of its passage, effectively frozen during its passage.   Such a particle might zip by at superlumal speed.  Of course we would never know it passed unless it hit something on the way.  Then we would have a mess.  

Physicists call hypothetical particles that travel at superlumal speeds tachyons, (hypothetical so far, that is).

There is one other consideration that acts as a speed regulator.  Something I hinted at above.   c is the speed at which the time and distance experienced by a photon reduces to zero.  I stated that a photon always strives to go faster than c.   Each time it does, it slips into imaginary time and pops back to c, and has to stay there.   Look at it another way.  The photon traveling at c arrives the instant it leaves (from the photon’s perspective).  If it went any faster than c, would it arrive before it left?  I don’t think so and so the photon cannot go any faster.

Hopefully I’ve given you something to think about.  

Oldtimer

Article and drawing, Copyright 2006, 2007,

James A. Tabb