So, at what speed does light travel as a wave opposed to a particle?

I have a bet with my granddaughters, if light as a particle is faster than a wave I loose. If a wave is at the same speed I win.

kv

 

You win. Sort of.

Of couse when dealing with waves there are two speeds: the phase velocity and the group velocity. The particle moves at the group velocity, which is what we call the speed of light.

Bob

 

You win. Sort of.

Of couse when dealing with waves there are two speeds: the phase velocity and the group velocity. The particle moves at the group velocity, which is what we call the speed of light.

Bob

My Idea comes from diffusion, light wins in a short distance gets diffused but, wave velocity is using a combined velocity, influencing other things such as electrons. This influence might or could behave faster at the other end of the universe. e.g. influencing other electrons in another part of the Universe, thus winning the speed of light. If one electron has influence on another elsewhere how does this influence the speed of light constant.

It's still light and still is constant but why?

kv

 

'Light' is just a small part of the EM spectrum so there's nothing special about its behavior other than how energy at that wavelength interacts with matter. 'Why' in this case is not a question current science can answer. From all observations, experiment and theories consistent with that data we see that there is a max speed limit for information transfer in the universe that is governed by the structure of spacetime as the values of magnetic permeability and electric permittivity in an empty volume of space. Nothing we have every observed in the deepest reaches of space has changed these values. Quantum Electrodynamic theory has only improved the precision of the values not changed them so it seems the 'speed of light ' is fundamental and unchanging across the universe.

The 'Why question is usually a complaint about the uncooperativeness of Nature behaving in ways that are not intuitively obvious.

 

So, at what speed does light travel as a wave opposed to a particle?

I have a bet with my granddaughters, if light as a particle is faster than a wave I loose. If a wave is at the same speed I win.

kv

The particle characteristic of light (the particles are called "photons" and each of them consist of one wave length) is based on the fact that light carries momentum (mv) in accordance with the formula mv=Planck's Constant/ Wavelength. Of course each wave length travels at the speed "c" which is 2.97 X 10 to the 8 meters/second. So the particle characteristic also travels at this same speed.

 

If you are correct I win by a draw and don't pay my $10. I wanted the twins to learn that of light duality then from that can't be concluded then our bet is null and void.

kv

 

If there is true duality then they have to be the same. Logically if there is a difference, then in science this would be a tool to differentiate the two conditions as completely seperate rather than co-existing states, which, as far as I know. has never been done except to show the practical results of each.

Tracy

 

According to Feynman the duality is false, light is always particles. You can find his lectures on this on YouTube. He’s quite adamant about it, and explains it.

IF Feynman is correct, there is no question here.

 

A little thought experiment based on photons moving faster than light waves. Think of the light coming from a star 100 light years away. If the particle travels faster the wave by 1% then the particle would arrive here a year before the wave! What does that even mean? We don’t see photons without wave characteristics.

Bob

 

According to Feynman the duality is false, light is always particles. You can find his lectures on this on YouTube. He’s quite adamant about it, and explains it.

IF Feynman is correct, there is no question here.

What did he really say in detail.

http://www.feynmanlectures.caltech.edu/I_02.html

Returning again to quantum mechanics and fundamental physics, we cannot go into details of the quantum-mechanical principles at this time, of course, because these are rather difficult to understand. We shall assume that they are there, and go on to describe what some of the consequences are. One of the consequences is that things which we used to consider as waves also behave like particles, and particles behave like waves; in fact everything behaves the same way. There is no distinction between a wave and a particle. So quantum mechanics unifies the idea of the field and its waves, and the particles, all into one. Now it is true that when the frequency is low, the field aspect of the phenomenon is more evident, or more useful as an approximate description in terms of everyday experiences. But as the frequency increases, the particle aspects of the phenomenon become more evident with the equipment with which we usually make the measurements. In fact, although we mentioned many frequencies, no phenomenon directly involving a frequency has yet been detected above approximately 10x12 cycles per second. We only deduce the higher frequencies from the energy of the particles, by a rule which assumes that the particle-wave idea of quantum mechanics is valid.

Conventional electromagnetics works at light frequencies. We can build nano-antenna THz dipoles that take into account the fuzzy nature of quantum-mechanical principles on structures this size.

https://www.nature.com/articles/srep04270

An infrared rectenna is a combination of a receiving nano antenna and a THz rectifying diode. Unlike photovoltaic where the conversion efficiency is limited by the semiconductor band gap, rectennas utilize the wave nature of light and can, theoretically, achieve 100% conversion efficiency. This statement, however, assumes perfect antenna metals, maximum reception by the antenna, and complete matching between the antenna and the rectifier. For a certain frequency of operation nano antennas must be optimized to produce the maximum field enhancement. The relatively high frequency of operation for THz rectennas leads to challenges not only in the fabrication of the nano antennas but also in the rectification process, since typical semiconductors based rectifiers do not have high enough switching speeds to rectify a THz signal. Moreover, the absence of mature theory and design equations for nano antennas makes these designs even more challenging.

 

What did he really say in detail.

http://www.feynmanlectures.caltech.edu/I_02.html

There are more details, and more lectures. But in the context of this question he did say that all we need to consider is particles, and that wave equations become probability of particle equations when dealing with electrons and photons.

See his explanation of the dual slit experiment for more clarity.

 

There are more details, and more lectures. But in the context of this question he did say that all we need to consider is particles, and that wave equations become probability of particle equations when dealing with electrons and photons.

See his explanation of the dual slit experiment for more clarity.

I think you're simplifying his explanation to the point of being meaningless. The wave equation and classical electrodynamics still work at THz. In Feynmans day the technology didn't really exist to necessitate use of wave behaviors in optical antenna structures, today it does.

 

I think you're simplifying his explanation to the point of being meaningless. The wave equation and classical electrodynamics still work at THz. In Feynmans day the technology didn't really exist to necessitate use of wave behaviors in antenna structures, today it does.

My understanding is different but I could surely be wrong. I am no physicist, nor a mathematician.

 

My understanding is different but I could surely be wrong. I am no physicist, nor a mathematician.

No problem. What Feynman talked about IRT to 'particles' of light in the dual slit experiment is really a measurement (measurement on any system causes a disturbance in the system) issue that shows how structure changes behaviors not a statement about the fundamental nature of 'light' being one or the other.
https://www.livescience.com/24509-light-wave-particle-duality-experiment.html

http://ecee.colorado.edu/~moddel/QEL/Papers/Moddel13a.pdf

The issue of whether a classical Maxwellian view of electromagnetic radiation
and rectification or an Einsteinian view of quantized photons applies to optical
rectennas will be discussed in this chapter. The classical-versus-quantum
dichotomy provides a foundation for understanding many of the issues in solar
rectenna technology.

 

The supposed duality of light is merely a consequence of sloppy language. When a physicist uses the word 'particle' or 'wave' in the context of quantum theory, she means something completely different than the usual Newtonian sense associated with it. The classical notions of particles and waves simply do not apply in quantum theories. Light is neither a classical particle nor a classical wave; the math makes this very clear, even if the language is confusing.

Note that light (or, more generally, electromagnetic energy) has no special status here: the same false-duality can be said about electrons and carbon atoms and everything else at these scales. Our commonsense ideas about particles and waves apply only in the limit ħ → 0, which marks the threshold between quantum and classical physics.

 

'Light' is just a small part of the EM spectrum so there's nothing special about its behavior other than how energy at that wavelength interacts with matter. 'Why' in this case is not a question current science can answer. From all observations, experiment and theories consistent with that data we see that there is a max speed limit for information transfer in the universe that is governed by the structure of spacetime as the values of magnetic permeability and electric permittivity in an empty volume of space. Nothing we have every observed in the deepest reaches of space has changed these values. Quantum Electrodynamic theory has only improved the precision of the values not changed them so it seems the 'speed of light ' is fundamental and unchanging across the universe.

The 'Why question is usually a complaint about the uncooperativeness of Nature behaving in ways that are not intuitively obvious.

I win for now. So, do they have anything more on the Solar Cell Tech maybe a prediction of when consumers could get it?

kv

Edit: I have twin granddaughters they teamed up against me, so I figured I would put it in here, I knew you might be able to simplify it enough that I could explain it.

 

I win for now. So, do they have anything more on the Solar Cell Tech maybe a prediction of when consumers could get it?

My prediction, for what it's worth, is not anytime soon. While it works and in theory has a higher possible EM conversion efficiency than bulk semiconductor junction photon conversion, the complexity of designing comparable commercial optical rectenna panels is an engineering nightmare.

https://briefs.techconnect.org/papers/harvesting-light-energy-with-optical-rectennas/

 

In my previous post, I wrote that the momentum of a photon is "mv = Planck's Constant / Wavelength".

However, since a photon does not have rest mass (m), its momentum is usually written as "p". I believe there are mathematical models of how a photon can carry momentum and the mass is an imaginary number. .

 

I'm writing a book, I mentioned an idea I had about how the Universe began, borrowing Indian beliefs as well as Christian I came to a point in my life while trying my best to understand Classical physics and the Standard Model e.g. Dark Matter or Dark Energy vs the energy and mass required to start the big bang.



I formulated that an Infinite amount of super white hot regional mass or energy vs an Infinite but opposite amount of negative or Dark Mass or Dark Energy. I pictured it this way in a circular motion energy passing from one to another (Indian belief) and could do so and existed in harmony for who knows how long. Until a force call it an intelligence in the center twist the circle touching the opposite sides creating a burst of energy, suddenly the circular motion appears to resemble the symbol infinity, two opposing forces come into contact with one another, battery cables, ground and hot, you get the picture.

In the emptiness of space came the big bang. Now Matter is formed & Time the clock has started while matter is forming in the emptiness of space once void, the flow of energy continues up "through" then up again and around back down through the "center" in a motion similar but different while Dark Matter or Dark Energy continually pull, stretch, cool, coalesce.

Forming worlds without end, and it hasn't stopped, won't stop until the force of it (intertwined) bends the symbol back to a circle from whence it came leaving Space,Time, and matter, which without matter could not include time both were intertwined or entangled.

kv

 

If the Big Bang was created from an infinite amount of mass or energy, there would still be an infinite amount of mass and energy left over today.

However, that has not been observed. So it can be concluded that the original energy or matter was in a finite quantity.

My questions are:
What was the object just before it exploded?
How long was it there before the Big bang?
Was it stable for a long period of time or was it caused by the sudden accretion of matter from a previous universe?
Then what caused it to explode?