How does light travel?

How does light travel?
Light moves at different wavelengths, represented here by the different colors seen in a prism. Credit: NASA and ESA

Ever since Democritus – a Greek philosopher who lived between the 5th and 4th century's BCE – argued that all of existence was made up of tiny indivisible atoms, scientists have been speculating as to the true nature of light. Whereas scientists ventured back and forth between the notion that light was a particle or a wave until the modern, the 20th century led to breakthroughs that showed that it behaves as both.

These included the discovery of the electron, the development of quantum theory, and Einstein's Theory of Relativity. However, there remains many fascinating and unanswered questions when it comes to light, many of which arise from its dual nature. For instance, how is it that light can be apparently without mass, but still behave as a particle? And how can it behave like a wave and pass through a vacuum, when all other waves require a medium to propagate?

Theory of Light in the 19th Century:

During the Scientific Revolution, scientists began moving away from Aristotelian scientific theories that had been seen as accepted canon for centuries. This included rejecting Aristotle's theory of light, which viewed it as being a disturbance in the air (one of his four "elements" that composed matter), and embracing the more mechanistic view that light was composed of indivisible atoms.

In many ways, this theory had been previewed by atomists of Classical Antiquity – such as Democritus and Lucretius – both of whom viewed light as a unit of matter given off by the sun. By the 17th century, several scientists emerged who accepted this view, stating that light was made up of discrete particles (or "corpuscles"). This included Pierre Gassendi, a contemporary of René Descartes, Thomas Hobbes, Robert Boyle, and most famously, Sir Isaac Newton.

Newton's corpuscular theory was an elaboration of his view of reality as an interaction of material points through forces. This theory would remain the accepted scientific view for more than 100 years, the principles of which were explained in his 1704 treatise "Opticks, or, a Treatise of the Reflections, Refractions, Inflections, and Colours of Light". According to Newton, the principles of light could be summed as follows:

  • Every source of light emits large numbers of tiny particles known as corpuscles in a medium surrounding the source.
  • These corpuscles are perfectly elastic, rigid, and weightless.

This represented a challenge to "wave theory", which had been advocated by 17th century Dutch astronomer Christiaan Huygens. . These theories were first communicated in 1678 to the Paris Academy of Sciences and were published in 1690 in his "Traité de la lumière" ("Treatise on Light"). In it, he argued a revised version of Descartes views, in which the speed of light is infinite and propagated by means of spherical waves emitted along the wave front.

Double-Slit Experiment:

By the early 19th century, scientists began to break with corpuscular theory. This was due in part to the fact that corpuscular theory failed to adequately explain the diffraction, interference and polarization of light, but was also because of various experiments that seemed to confirm the still-competing view that light behaved as a wave.

The most famous of these was arguably the Double-Slit Experiment, which was originally conducted by English polymath Thomas Young in 1801 (though Sir Isaac Newton is believed to have conducted something similar in his own time). In Young's version of the experiment, he used a slip of paper with slits cut into it, and then pointed a light source at them to measure how light passed through it.

According to classical (i.e. Newtonian) particle theory, the results of the experiment should have corresponded to the slits, the impacts on the screen appearing in two vertical lines. Instead, the results showed that the coherent beams of light were interfering, creating a pattern of bright and dark bands on the screen. This contradicted classical particle theory, in which particles do not interfere with each other, but merely collide.

The only possible explanation for this pattern of interference was that the light beams were in fact behaving as waves. Thus, this experiment dispelled the notion that light consisted of corpuscles and played a vital part in the acceptance of the wave theory of light. However subsequent research, involving the discovery of the electron and , would lead to scientists considering yet again that light behaved as a particle too, thus giving rise to wave-particle duality theory.

Electromagnetism and Special Relativity:

Prior to the 19th and 20th centuries, the speed of light had already been determined. The first recorded measurements were performed by Danish astronomer Ole Rømer, who demonstrated in 1676 using light measurements from Jupiter's moon Io to show that light travels at a finite speed (rather than instantaneously).

By the late , James Clerk Maxwell proposed that light was an electromagnetic wave, and devised several equations (known as Maxwell's equations) to describe how electric and magnetic fields are generated and altered by each other and by charges and currents. By conducting measurements of different types of radiation (magnetic fields, ultraviolet and infrared radiation), he was able to calculate the speed of light in a vacuum (represented as c).

In 1905, Albert Einstein published "On the Electrodynamics of Moving Bodies", in which he advanced one of his most famous theories and overturned centuries of accepted notions and orthodoxies. In his paper, he postulated that the speed of light was the same in all inertial reference frames, regardless of the motion of the or the position of the observer.

Exploring the consequences of this theory is what led him to propose his theory of Special Relativity, which reconciled Maxwell's equations for electricity and magnetism with the laws of mechanics, simplified the mathematical calculations, and accorded with the directly observed speed of light and accounted for the observed aberrations. It also demonstrated that the speed of light had relevance outside the context of light and electromagnetism.

For one, it introduced the idea that major changes occur when things move close the speed of light, including the time-space frame of a moving body appearing to slow down and contract in the direction of motion when measured in the frame of the observer. After centuries of increasingly precise measurements, the speed of light was determined to be 299,792,458 m/s in 1975.

How does light travel?
Artist’s impression of two photons travelling at different wavelengths, resulting in different- colored light. Credit: NASA/Sonoma State University/Aurore Simonnet
Einstein and the Photon:

In 1905, Einstein also helped to resolve a great deal of confusion surrounding the behavior of electromagnetic radiation when he proposed that electrons are emitted from atoms when they absorb energy from light. Known as the photoelectric effect, Einstein based his idea on Planck's earlier work with "black bodies" – materials that absorb electromagnetic energy instead of reflecting it (i.e. white bodies).

At the time, Einstein's photoelectric effect was attempt to explain the "black body problem", in which a black body emits electromagnetic radiation due to the object's heat. This was a persistent problem in the world of physics, arising from the discovery of the electron, which had only happened eight years previous (thanks to British physicists led by J.J. Thompson and experiments using cathode ray tubes).

At the time, scientists still believed that electromagnetic energy behaved as a wave, and were therefore hoping to be able to explain it in terms of classical physics. Einstein's explanation represented a break with this, asserting that electromagnetic radiation behaved in ways that were consistent with a particle – a quantized form of light which he named "photons". For this discovery, Einstein was awarded the Nobel Prize in 1921.

Wave-Particle Duality:

Subsequent theories on the behavior of light would further refine this idea, which included French physicist Louis-Victor de Broglie calculating the wavelength at which light functioned. This was followed by Heisenberg's "uncertainty principle" (which stated that measuring the position of a photon accurately would disturb measurements of it momentum and vice versa), and Schrödinger's paradox that claimed that all particles have a "".

In accordance with quantum mechanical explanation, Schrodinger proposed that all the information about a particle (in this case, a photon) is encoded in its wave function, a complex-valued function roughly analogous to the amplitude of a wave at each point in space. At some location, the measurement of the wave function will randomly "collapse", or rather "decohere", to a sharply peaked function. This was illustrated in Schrödinger famous paradox involving a closed box, a cat, and a vial of poison (known as the "Schrödinger's Cat" paradox).

According to his theory, wave function also evolves according to a differential equation (aka. the Schrödinger equation). For particles with mass, this equation has solutions; but for particles with no mass, no solution existed. Further experiments involving the Double-Slit Experiment confirmed the dual nature of photons. where measuring devices were incorporated to observe the photons as they passed through the slits.

When this was done, the photons appeared in the form of particles and their impacts on the screen corresponded to the slits – tiny particle-sized spots distributed in straight vertical lines. By placing an observation device in place, the wave function of the photons collapsed and the light behaved as classical particles once more. As predicted by Schrödinger, this could only be resolved by claiming that light has a wave function, and that observing it causes the range of behavioral possibilities to collapse to the point where its behavior becomes predictable.

The development of Quantum Field Theory (QFT) was devised in the following decades to resolve much of the ambiguity around wave-particle duality. And in time, this was shown to apply to other particles and fundamental forces of interaction (such as weak and strong nuclear forces). Today, photons are part of the Standard Model of particle physics, where they are classified as boson – a class of subatomic that are force carriers and have no mass.

So how does light travel? Basically, traveling at incredible speeds (299 792 458 m/s) and at different wavelengths, depending on its energy. It also behaves as both a wave and a particle, able to propagate through mediums (like air and water) as well as space. It has no mass, but can still be absorbed, reflected, or refracted if it comes in contact with a medium. And in the end, the only thing that can truly slow down or arrest the speed of light is gravity (i.e. a black hole).

What we have learned about and electromagnetism has been intrinsic to the revolution which took place in physics in the early 20th century, a revolution that we have been grappling with ever since. Thanks to the efforts of scientists like Maxwell, Planck, Einstein, Heisenberg and Schrodinger, we have learned much, but still have much to learn.

For instance, its interaction with gravity (along with weak and strong nuclear forces) remains a mystery. Unlocking this, and thus discovering a Theory of Everything (ToE) is something astronomers and physicists look forward to. Someday, we just might have it all figured out!


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Experiment suggests it might be possible to control atoms entangled with the light they emit by manipulating detection

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May 20, 2016
I had always assumed light was the result of energy bouncing back and forth at the junction of two dimensions. From our perspective, it pops into existence, pushes outward with enough force to balloon out from the barycenter to the dimensions of the waves we are familiar with. Whatever is at the barycenter then drops back out of existence for what seems like no observable time before popping up again a Planck length from its last appearance.
Because the distance traveled per second is limited by its sewing machine like path in the observable universe, additional energy only increases the EM distortion further away from the barycenter, it doesn't increase the observed velocity.


May 21, 2016
"And in the end, the only thing that can truly slow down or arrest the speed of light is gravity (i.e. a black hole)."

This casually-tossed statement violates Einstein's conception that the speed of light (in a vacuum) is a constant within its own frame of reference.

From within the frame of a black hole, light is following a path curved by excessive gravity, so curved that it cannot escape. But it's still moving at C in that frame.

Of course General Relativity predicts that time will pass more slowly within deep gravity wells like black holes than in places where gravitational effects are small (like Earth). But that isn't photons slowing down. It's time distortion between two relative frames, ours and the black hole's.

According to GR, we should not expect the quote above to be a true statement.

May 21, 2016
The first recorded measurements were performed by Danish astronomer Ole Rømer

Just read up on this...That was a rather clever observation of his (and the initial calculation of the speed of light was also quite good given the tools he had)

May 21, 2016
Phys1 wrote, "Firstly, light does not have a frame of reference with special relativity."

I was not referring to the photon's frame of reference, but the frame through which it travels. According to SR, to a photon its travel is instantaneous; e.g. it takes no time at all.

"Secondly, in my understanding light can be slowed down by gravity as observed from outside the range of that gravity. The cause is that time runs slower there."

In the frame through which it travels, it is still moving at c. It has not slowed down. It has, however, been subjected to time distortion imposed by the black hole's intense gravitation, relative to an external frame which does not share the black hole's gravitational field..

May 21, 2016
And in the end, the only thing that can truly slow down or arrest the speed of light is gravity (i.e. a black hole).


The author should embark on a study of SR & GR & realize that Electro-magnetic energy does not exist at any speed other than what Einstein proved in his SR Mass/Energy Equivalence Principle as calculated by E=mc².

Furthermore, if he had ever studied General Relativity he'd know from application of the Einstein Field Equations that the field of gravity that would be required to slow a photon to zero velocity from the surface of a stellar body would be a quantity of gravity that is incalculable, infinity.

This author imagines a means of using the Photon Deflection calculation Einstein used to calculate gravitational lensing of starlight passing the immediate peripheral disk of the Sun. Okay, so here's the equation Einstein used: Deflection of light by the sun = 4GM/c²R.........let's see if the Author is up to proving gravity can slow EM velocity.

May 21, 2016
Once again Benni, you entirely miss the point of E=mc². That equation is the *conclusion* one can draw from *assuming* the speed of light is constant (and some other things). In fact, it's useless to describe light entirely because light has 0 mass. So E=0c²=0. Obviously light doesn't have 0 energy.

The *complete* equation has always been E²= (Pc)² + (mc²)². *Only* in the case where an object is at rest is P=0, and thus the equation becomes E=mc². However, for a massless object (like a photon), the mc² term drops out and you get E=pc. Light's energy equals its momentum times c.

---

Furthermore, there's a minor misconception that I can't entirely vouch for personally as I haven't done the maths. What the author *may be* referring to is how a distant observer views the speed of light near a gravitational body (as Phys1 points out above). The 'light always travels at c' only applies to local observations where space-time is flat apparently.

May 21, 2016
The *complete* equation has always been E²= (Pc)² + (mc²)². *Only* in the case where an object is at rest is P=0, and thus the equation becomes E=mc². the mc² term drops out and you get E=pc. Light's energy equals its momentum times c.


A complete meaningless obfuscation of the the point I was making of the fact that photons cannot exist in a state where velocity is anything other than lightspeed, so here's the rest of the equation you missed that directly relates the EM Energy:

E=mc² = hv = hc/ λ = hc/0 = ∞ (infinity is a meaningless result)

E is energy,
h is Planck's constant per particle
c is speed of light
λ is the wavelength (energy) of the photon

Because the Energy of a photon is it's wavelength (λ), there must exist a force of gravity that reduces EM Escape velocity to zero, hence also the wavelength to zero..

Set λ to 0, the resulting equation is E= hc/0 = ∞. Where does the Infinite Energy come from that reduces λ to zero?


May 21, 2016
Hi Benni. :)
Because the Energy of a photon is it's wavelength (λ), there must exist a force of gravity that reduces EM Escape velocity to zero, hence also the wavelength to zero..

Set λ to 0, the resulting equation is E= hc/0 = ∞. Where does the Infinite Energy come from that reduces λ to zero?
Careful, mate. It is the frequency, not the wavelength, that must be zero for a photon to have zero energy.

Consider the hypothetical case of a photon at, or infinitesimally just above, a BH horizon: if it tries to propagate radially away from there, its wavelength actually gets 'stretched' to 'infinity', while its frequency is reduced to effectively 'zero'. See?

So it's 1/λ that your equation involves in order to give the zero energy result. In other words, the photon energy 'result' gets SMALLER the GREATER the 'λ' value, because it appears as a DENOMINATOR and the fraction gets smaller as the 'λ' gets larger; which is what you pointed out already.

Cheers. :)

May 21, 2016
The electromagnetic waves are periodic propagating oscilation in the structure of vacuum of space caused by physical interactions between this structure and electrons.
I have no idea why such alleged authorities Like the autor of GR believe that the speed of light is constant throughout the whole universe when teh structure of vacuum of space can be programmed differently in different places in the universe according the ideas of the Creator.

May 21, 2016
Plank constant is not constant at all.

May 21, 2016
Because the Energy of a photon is it's wavelength (λ), there must exist a force of gravity that reduces EM Escape velocity to zero, hence also the wavelength to zero.


Careful, mate. It is the frequency, not the wavelength, that must be zero for a photon to have zero energy.


RC, you need to take a course in 1st & 2nd semester chemistry and/or 2nd semester Physics & study the terminology of the Electro-Magnetic Spectrum. The ENERGY SPECTRUM of Electro-magnetism is FREQUENCY alias WAVELENGTH.....all three are one in the same.

May 21, 2016
Consider the hypothetical case of a photon at, or infinitesimally just above, a BH horizon:


How can a photon exist "infinitesimally just above, a BH horizon" ? That phrase is meaningless gobblygook.

if it tries to propagate radially away from there, its wavelength actually gets 'stretched' to 'infinity', while its frequency is reduced to effectively 'zero'.


The author is not talking about photons propagating radially away from the BH Event Horizon, he is talking about "gravity" emanating from the BH which intrinsically implies it's surface, not some undefined distance above the surface of the BH where an EH is presumed to exist.

its wavelength actually gets 'stretched' to 'infinity'
How do you know this? What stretches the wavelength (frequency) of EM Waves to "infinity"? Never heard of such a thing. An EM wave stretched such that it has a frequency (wavelength) "stretched to infinity" is a photon with zero energy hence zero wavelength.

May 21, 2016
So it's 1/λ that your equation involves in order to give the zero energy result.


RC, it isn't my equation, it is Einstein's. I'm simply demonstrating the final result of the equation if the wavelength (λ) is set to zero which is where it must be set to prevent a photon from rising from the surface of a BH, in other words the ENERGY of a photon must be rendered to zero to keep it from moving any distance whatsoever, otherwise it moves at a velocity of lightspeed at any FREQUENCY (Energy, Wavelength) above zero, there is no middle ground here where the velocity of a photon is somehow affected by any gravity field in existence anywhere in the Universe.

It appears to me that you're trying to make a photon comport with the equation 1/2mv² which is Kinetic Energy, the WORK equation for particles moving less than the speed of light, don't mix that up with E=mc². Velocity of particles governed by 1/2mv² is highly variable but understand photons do not exist at 0 velocity.


May 21, 2016
"Consider the hypothetical case of a photon at, or infinitesimally just above, a BH horizon: if it tries to propagate radially away from there,"

I think you meant EH.
Photons do not try, they do what the local geodesic tells them to do.

May 21, 2016
Apr 14, 2016

When wavelength of a photon is reduced to zero, as must be the final result to prevent a photon from reaching Escape Velocity from the surface of a BH,...


The photon is red-shifted by the gravitational field, so it's the frequency that goes to zero. Wavelength becomes infinite
......Okay del2, you want in on the calculation, so just how about if you give us the equation by which to calculate the amount of redshift a given quantity of gravity will create on a photon of whatever frequency you care to pick. You've been making the claim, so put up your math to back it up.................breathlessly waiting.

Photons do not try, they do what the local geodesic tells them to do.
TehDog.......what is this? You make photons appear like little flocks of sheep just sort of being herded around inside a pasture with a dog name of Geodesic nipping at their heels.


May 21, 2016
All right, Benni, you invited me in via a quote from a different thread, so I will reply.
You wrote:
"Because the Energy of a photon is it's wavelength (λ), there must exist a force of gravity that reduces EM Escape velocity to zero, hence also the wavelength to zero..
Set λ to 0, the resulting equation is E= hc/0 =∞. Where does the Infinite Energy come from that reduces λ to zero? "

This is self-contradictory and wrong.
The energy of a photon is not its wavelength.

You also wrote:
"The ENERGY SPECTRUM of Electro-magnetism is FREQUENCY alias WAVELENGTH.....all three are one in the same. "
No, they are not. Frequency is not the same as wavelength.
You don't seem to have the smallest clue about waves.

The comment editor isn't suitable for entering the equations you want, but if you want equations for gravitational red shift, try here:
http://www.physic...edshift/

May 21, 2016
@Benni
The editor wouldn't let me enter the other URL I wanted to suggest for you, but go to http://astro.phys...mathcad/ and select addendum 10.

May 22, 2016
Phys1 asked, "In which reference frame? Indeed, in a frame that comoving with the light in a liniting sense."

It's just a thought experiment. Anything moving at C experiences no time passing from the start to the end of its journey. Of course we can't experience that frame. It might not even be correct to call it a 'frame of reference.'

That's just an aside. The frame of reference I was referring to is the black hole's spacetime frame, where a photon follows a curved path that does not allow it to leave the black hole, but travels at c. It is not slowed in that reference frame. Relative to a frame outside of the black hole, of course, everything in that deep gravity well, including the photon, is time-distorted.

May 22, 2016
I think light slows down whenever it travels through a material with index of refraction >1

May 22, 2016
The ENERGY SPECTRUM of Electro-magnetism is FREQUENCY alias WAVELENGTH.....all three are one in the same.


No, they are not. Frequency is not the same as wavelength.
You don't seem to have the smallest clue about waves.
......Ok then, mister Big Clue versus my "smallest clue", you explain the differences in "frequency" versus "wavelength" and explain why those differences have nothing to do with the EM Energy Spectrum.


May 22, 2016
....Ok then, mister Big Clue versus my "smallest clue", you explain the differences in "frequency" versus "wavelength" and explain why those differences have nothing to do with the EM Energy Spectrum.

The frequency of a wave is the number of waves passing a given point per second. It is a pure number divided by a time.
The wavelength is the distance from one point on a wave to the next point that is in phase with it (in simple terms, the distance from one peak of the wave to the next peak). It is a length, measured in units of length, e.g. metres in SI units.
Frequency and wavelength are _not_ the same thing, though they are related: the product of frequency and wavelength is the speed of the wave.
The electromagnetic spectrum is the range of all frequencies of electromagnetic waves.
Your statement "The ENERGY SPECTRUM of Electro-magnetism is FREQUENCY alias WAVELENGTH.....all three are one in [sic] the same. " is clearly wrong; they are NOT one and the same.

May 22, 2016
Frequency and wavelength are _not_ the same thing, though they are related: the product of frequency and wavelength is the speed of the wave.
.......So you still can't figure this out can you? And to top it off you even appear to imply that not all frequencies of the EM Energy Spectrum propagate at the same velocity.

You imply the wavelength (frequency, energy) of a photon has magical properties that causes variability in "the speed of the wave".

Alright Mr Smarter than Einstein, put up your math by which you can demonstrate a "product of frequency" causing the velocity of an EM wavelength to be anything other than the accepted standard of velocity. For example, cite the math explaining how gravity at the surface of a BH prevents an EM wave from reaching Escape Velocity by somehow contorting the waveform into some manner of infinity or to zero as you seem to think is possible. You imagine you can apply Einstein's calculation for Photon Deflection to do this?


May 22, 2016
Frequency and wavelength are _not_ the same thing, though they are related: the product of frequency and wavelength is the speed of the wave.
.......So you still can't figure this out can you? And to top it off you even appear to imply that not all frequencies of the EM Energy Spectrum propagate at the same velocity.

You imply the wavelength (frequency, energy) of a photon has magical properties that causes variability in "the speed of the wave".

What can't I figure out? The relationship speed = frequency × wavelength holds for any wave, not just em waves. There is no magic. How do I appear to imply that not all em frequencies travel at the same velocity? You quote this equation yourself, in posts above. (hv = hc/ λ i.e. ν = c/ λ)
If you were one of my students you would get a fail for being so obtuse.
If you can't respond sensibly I'll just put you on my ignore list and do my blood pressure a favour.

May 22, 2016
Hi Benni. :)

The thrust of your point was OK, but your explanation of which term needed to be 'zero' was not technically correct. The term 1/λ=0 (not λ=0 per se). See?

Then your logic/argument is consistent with your thrust.

I wasn't disagreeing with your thrust, only with your 'explanation' of what term was zero in the extreme case on which your argument is based.

As to the issue of frequency and wavelength, again, I was only pointing out that while your thrust is ok in the context, your specific explanation treated frequency and wavelength 'values' as 'identical' (ie, you stated that both were 'zero').

Can you see that the two values are diametrically opposed trending values? Ie, if the 'frequency' term is set to zero 'value' in a maths equation, then its 'inverse value' must be set to 'infinity' for its corresponding 'wavelength' term if that is input to the equation regarding parameters of the same photon entity being treated in that equation. Cheers. :)

May 22, 2016
Hi TehDog. :)
I think you meant EH.
Yep, as understood according to the context involved.
Photons do not try, they do what the local geodesic tells them to do.
It was a figure of speech, again, understood in the context involved.

Obviously you understood both points in context; so has everyone else. Using the strict technical terminology would have taken too long and non-scientists may have missed the point. Hence my use of that figure of speech to create the image in the non-scientist readers mind so as to get the point regardless of semantic and pedant considerations. Thanks anyway; at least it shows you are paying attention. Which is good to see. Cheers. :)

May 22, 2016
What can't I figure out?


Precisely this:
The relationship speed = frequency × wavelength holds for any wave, not just em waves.
You are confusing Kinetic Energy 1/2mv², with Electro-Magnetic Energy E=mc² with this comparison.

How do I appear to imply that not all em frequencies travel at the same velocity? You quote this equation yourself, in posts above. (hv = hc/ λ i.e. ν = c/ λ)


So you think the "v" in the equation ν = c/ λ is VELOCITY? I have very bad news for you, it isn't. The VELOCITY of light is expressed in the numerator as "c".
If you were one of my students you would get a fail for being so obtuse
..........It would be more fitting to rephrase your preceding statement to something more like: If you were one of my Chemistry or Physics Professors you would get a fail because you obviously can't read the terms of an equation.

Here's how the VELOCITY of EM Waves is calculated from E=mc²: Transposing c²=E/m......c=√E/m.


May 22, 2016
As to the issue of frequency and wavelength, again, I was only pointing out that while your thrust is ok in the context, your specific explanation treated frequency and wavelength 'values' as 'identical' (ie, you stated that both were 'zero').


Expressing "values" of measurements is a completely different issue that is separate from applying the definitions of "frequency" & "wavelength" as identical.

May 22, 2016
You are confusing Kinetic Energy 1/2mv², with Electro-Magnetic Energy E=mc² with this comparison.

No, I'm not. (In fact, Einstein derived E=mc² using kinetic energy. The equation isn't just for EM energy). Anyway, I didn't 'derive' the velocity from the energy equation.
So you think the "v" in the equation ν = c/ λ is VELOCITY?

No, I don't, nor did I say so. c is the velocity, ν is 'nu', the frequency. Rearrange the equation and you get c=νλ. See? Velocity = frequency × wavelength
Here's how the VELOCITY of EM Waves is calculated from E=mc²: Transposing c²=E/m......c=√E/m.

Yes, I know. So? How does that affect the fact that frequency and wavelength are different?
You clearly have no understanding of waves, Benni.


May 22, 2016

So you think the "v" in the equation ν = c/ λ is VELOCITY?


No, I don't, nor did I say so
Yeah, I know, what you have been saying is that the velocity of light can be altered via of somehow altering it's wavelength (frequency, energy), then when you got caught off base & were tagged out on that assertion & lost that argument, you changed your stance to creative postulations of the difference between "frequency" & "wavelength", neither one of which had anything to do with your original assertion.

At what level of education do you teach? Sounds a lot to me like grade school level from what you've so far demonstrated in your comprehension of Einstein's Mass/Energy Equivalence Principle. By the way, I spent 6 years in Engineering School studying Nuclear & Electrical Engineering.


May 23, 2016
Another aspect of the story: viXra.org/abs/1509.0272?ref=8866874

May 23, 2016

So you think the "v" in the equation ν = c/ λ is VELOCITY?


No, I don't, nor did I say so
Yeah, I know, what you have been saying is that the velocity of light can be altered via of somehow altering it's wavelength (frequency, energy),

No, I never said that anywhere, nor did I imply that.
then when you got caught off base & were tagged out on that assertion & lost that argument, you changed your stance to creative postulations of the difference between "frequency" & "wavelength",
standard definitions, you mean.

By the way, I spent 6 years in Engineering School studying Nuclear & Electrical Engineering.

I find that really hard to swallow given the rubbish you post here, and the way you misunderstand others' posts.
Now I'm putting you on ignore; I've had enough of your rubbish.
Bye, Benni.

May 31, 2016
If you can understand the quantum construction of electrons and positrons' it would help clear up the information on photons, right now we believe electrons are negatively charged particles with no sub structure , we don't have the instruments to see its true construction ,I suspect its a two level quantum construction with a negatively charged dominant charge by quantum mass with a minority quantum mass on one level bonded by attraction ,in which enables it to field chain with other electrons into magnetic lines of force without repelling other electrons magnetically, and the positron is an electron but with a three level quantum construction with an added level on the electron dominant negative side of a positive dominant quantum level. Preventing that construction from field chaining into magnetic lines with other positrons, and those to particles fused together make a equal charged photon

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