Skip to content

The Nature Of Light

At 8:00am I wake up, drink some coffee, shower and am into work at 8:30am. You work directly with me and spend the entire morning from 8:30am until 12:00pm along side me, following my every movement. At 12:00pm we go to lunch together, returning to work at 1:00pm. From that time until 5:00pm you never leave my side. At 5:00pm we leave work and head out to dinner together where we discuss the day's findings and observations. At 9:00pm we depart the restaurant and each head to our separate homes. At 9:15pm I have a few glasses of mead at home and go to bed at 9:30pm.

While this is completely unrealistic for my actual schedule and does not allow for separate bathroom breaks at the work place it will suffice for the topic at hand; and that is the nature of light. Of a 13 hour and 30 minute day, you would have spent 12 hours and 30 minutes with me, or 92.6% of my waking day. From the time spent with me you could observe that I am capable of walking in a straight line. As a matter of fact, you could infer that 100% of the time I am capable of walking in a straight line. With me so far?

What you do not see is the 2 minutes when I first wake up and wander to the coffee pot for my first cup of coffee, often bumping into the walls of the hallway on my journey for caffeine. Nor do you see the 2 minutes between when the alcohol from the mead kicks in and I make my way back into bed. For those 4 minutes or 0.49% of the day I am not capable of walking a straight line. 4 minutes of the day that 99.99999% of the world will never observe, unless you were stationed with me in the Navy, at which case you saw me stumbling drunk a lot.

The nature of light is like this. Just as you will never get the chance to observe those 4 minutes where I am incapable of walking a straight line, the circumstances that cause light to behave against the established rules are extremely unlikely to be observed. Thus we infer that light travels at a constant speed of 299,792,458 meters per second and that it behaves like a particle and a wave.

If you have ever met me or read my blog prior to this moment you already know I am going to tell you that light does not travel at a constant speed nor is it both a particle and wave. It is just a particle that usually travels at 299,792,458 m/s. Being who I am, you really should just take my word for it, but I know you will want some sort of proof of this outlandish claim.

The slit experiment is a good place to start. Before I say anything else on the subject, let me just state that the slit experiment, or double-slit experiment, is viewed as a thought experiment by quantum physicists as opposed to actually showing anything explainable. Basically they know that something interferes with the particles of light to make them appear as a wave, but aren't sure why that could be and so call it a thought experiment instead, pretending that light (and other particles) behave as both a particle and a wave.

Now that I have that out of the way if you happen to have access to the proper lab equipment give the following a try:
1. Perform the double-slit experiment, recording the pattern of photons that collect on the screen using the same material for the entire barrier (the thing that has the slits cut in it).
2. Perform the experiment a second time, exactly the same way. You should observe a similar wave pattern formed on the screen.
3. Now replace 1/2 of the barrier (i.e. one of the slits) with a different composition of material, ensuring the slit has the same dimensions and is located in the same location. The result should be a different wave form on the screen from the previous two runs. Cool stuff, right?
4. For something really cool, perform the double-slit experiment in a vacuum using a barrier composed of black body single-walled carbon nanotubes.

Lacking access to a NASA Space Shuttle, astronaut training, lasers and black body material I can't prove what you will see in experiment #4, but what it should be (and I would put large sums of money on this) is a lack of wave forming. You see, the waves of the slit experiment are not formed because light is a waveform, but rather because of the photons coming near and bouncing off a combination of the sides of the slits in the barrier and the molecules present in air.

When light hits a given atom or molecule at a particular angle, it behaves in a very predictable manner. That predictability is tied in to the frequency of the orbits (both electron and nucleus) of an atom. When you remove the deflection from the walls of the barrier using a black body material and the interference caused by molecules in the air, you take away light's ability to mimic wave behavior. Instead you get the real nature of light, which is particles. Now fly up to space and try it out, I'll continue on by covering the speed of light while we await your return.

The first thing I should cover is the law of conservation of energy, which states that energy does not just disappear, or rather does not get used up. Instead energy changes forms, from one type, like kinetic, to another type, like potential. The amount of energy available stays the same.

Photons, or light particles, have a specific amount of energy in the form of kinetic energy. When that photon impacts something, that energy gets transferred to that something, usually in the form of thermal energy (heat). Plants are really good at absorbing all that energy instead of allowing it to become thermal energy, solar cells are not so good. This is why a leaf does not get as hot as a solar cell in bright sunlight.

A photon is only capable of holding so much energy, which as I said takes the form of kinetic energy, allowing the photon to travel through space at a rate of 299,792,458 m/s; usually. It would take additional energy to allow that photon to travel faster than its normal speed, but it can't hold that additional energy. I would guess that super energy saturation is theoretically possible, but unlikely to occur naturally, so light does not travel faster than the speed of light very often (just on open roadways with no police cars around).

Photons can be slowed down though. Light gets affected by intense gravitational forces such as that present in stars and black holes. It also gets affected by planetary gravitational forces, hence the lens effect seen around planets (light gets curved around it). When gravity acts upon light to slow it down, or any moving object for that matter, the kinetic energy does not go away, but rather becomes potential energy. Once the gravitational field is no longer acting upon the photon, the potential energy turns right back into kinetic energy and off the little particle goes.

Now, if you happen to be a physicist reading this you are no doubt spouting off about it being spacetime distortions caused by gravitational fields. Of course no physicists read my blog, or they are too afraid to respond, but in the unlikely event that you are a physicist; let me tell you that you are only spouting off about spacetime because you have been taught it as sound scientific theory. It doesn't really exist.

Ok, ok. Andrew's a whack job. Probably wears an aluminum foil hat to keep out the mind control rays. I assure you I do not, the aluminum foil hat is just fashionable and I only wear it with the proper ensemble. All kidding aside, let's try a thought experiment of our own, assuming you haven't drunk too much of the grape Kool-Aid already.

Assume for just an instant that Einstein had never come up with any of the theories of relativity or spacetime or any of that stuff. You send a radar signal at the planet Mercury and record the amount of time for the round trip. You know the distance to Mercury and the speed of light, so you should have a good idea of how long it should take before you "hear" that echo. Only when you send that radar signal out to Mercury such that it passes very close to the Sun, it takes longer for the signal to make its round trip than it should.

Now either Mercury jumped out of its orbit and further away from Earth for that instant, or something else happened. Disregarding spacetime, make your inference. If you put down the Kool-Aid, you will infer that something slowed down the radar signal, with the likely culprit being the gravitational force of the Sun. We do know, after all, that gravity can affect light particles.

The above experiment should look familiar to physics students, as it is the same experiment used by Irwin Shapiro to test general relativity and produce the Shapiro Time Delay effect. Simply because general relativity is accepted we call it a time delay, rather than gravity slowing down a photon.

The reality is that photons get slowed down by the gravity of the sun. Just a tiny bit, because they are travelling so very very fast to begin with (back to my theory there). Even more so, the photon gets curved ever-so-slightly around the Sun, but luckily enough, on the return trip the Sun curves the trajectory back on path to be received by the awaiting radar dish.

This is all just food for thought for the time being. The proof of this concept comes from a modified version of the Shapiro test and also explains why the frame-dragging effect really occurs. I'll cover that in a later entry, but for now I have rambled on long enough. In the mean time, put down the Kool-Aid and start thinking logically.


I Am. When? on : Quack Science

Show preview
xkcd had this great comic strip up today (shown above). Of course it got me thinking about how have been neglecting my own pet physics notions and that I really fall into the same realm as the comic (what scientists respectfully call "quack scie


Display comments as Linear | Threaded

Anna on :

Thinking of a light as a particle means that those particles should have some mass, but comparing this to Einstein theory we need to say also that for every particle that wants to travel with the speed of light the mass would grow almost to infinity. We could take a conclusion from this: particle of light has no mass at all, or infinite energy to move that huge mass.

Andrew Maxim on :

Hi Anna,

Thank you for the feedback. Like most modern physicists have done, and continue to do, you are assuming that E=mc^2 and Einstein's theory are 100% correct. Or more precisely that E=mc^2 is a true function and contains an inverse function.

Much like sin, cos and tan functions, there is no real inverse function for E=mc^2. It works properly in one direction, and that is to solve for the energy contained in matter. More specifically, the energy contained in matter during its natural state (i.e. no additional energy added or subtracted). Of course the speed of light squared is probably not the actual number needed either, as I think any sufficiently large number would have worked just as well, but Einstein was obsessed with the speed of light and so that is what was used.

For those specific instances where you invert the function and solve for matter in its natural state (again, at rest with no additional energy having been applied or removed) it will work as an inverse function. That is because all mass has inherent energy, which this will solve for. However, not all forms of energy have a relatable mass, hence the reason it is not a truly invertible function.

Actually there is no form of energy that has mass, just that there is a given amount of energy inherent in a given amount of mass. Additional energy added or removed from that mass, without adding or removing particles of matter itself (i.e. no adding electrons or removing neutrons, or quarks, etc) does not cause the mass of the matter to change. Sometimes the density changes, but not the mass.

If you take this into consideration and suddenly light does not have an infinite mass (and energy) because of the energy associated with its speed, nor does it lack mass. Instead it is a particle that has some mass, albeit not a mass that is currently measurable. Of course you would have to stop a particle of light to measure its mass anyway, and then, well, it would cease to be a particle of light and instead be just a very very tiny particle. ;-)

Add Comment

Enclosing asterisks marks text as bold (*word*), underscore are made via _word_.
Standard emoticons like :-) and ;-) are converted to images.
E-Mail addresses will not be displayed and will only be used for E-Mail notifications.
Form options