Speed C is Dependant Upon Source?

In summary, the conversation was about the importance of effective communication in the workplace. The speakers discussed how communication can improve teamwork, productivity, and overall success in a company. They also emphasized the need for active listening and clear communication to avoid misunderstandings and conflicts. Additionally, they mentioned the role of technology in modern communication and the potential challenges it can bring. Overall, the conversation highlighted the crucial role of communication in the workplace and the benefits it can bring when done effectively.
  • #106
Tom Mattson said:
What does QM teach us? It teaches us that particles act as waves. These waves are referred to as matter waves.
Gotcha - fair enough. I thought you meant sound waves or the like.
 
Physics news on Phys.org
  • #107
Tom Mattson said:
Where are you getting this from?

First, the change in velocity is a vector, and the energy of a photon is not. There is no way that one could be proportional to the other.

I get it from this simple equation.

KE = 1/2 m * v ^2

where m = mass of photon

v = speed of photon (velocity has direction, which is included in the energy equation.)

Therefore, if photon mass is consistent, a change in speed changes photons energy. If the photon doesn't change speed, then does it's mass change during recoil?

If the photon doesn't change speed or mass during recoil, then where does the energy go? Conservation of energy represents that a change of energy on one side of the equation is proportionate to the other side of the equation, where one side is a atom and it's property recoil and the other is a photon emission.

Please explain that equation. I'm not sure if it infers the photon has change in it's mass or velocity when the atom in the equation appear to.

Tom Mattson said:
Either the human senses it, or the instrument does. I stand by my original statement: humans don't sense atomic recoil. It's below the threshold of our sense of touch.

If an instrument senses recoil, for us to know the instrument senses recoil, we have to sense the instrument sensing recoil. If we know it sensed it, we indirectly sense recoil. Instrument aided sense. All sense is indirect really, we don't sense the objects we sense a piece of the chain of a chain reaction. I'm basing this on the fact that thought or sense of a physical object is an expression of the object rather than the object. Which assures me, we've sensed the photon, because it has mass. Without mass, it sends no expression properties of its existence.
 
Last edited:
  • #108
omin said:
If the photon doesn't change speed or mass during recoil, then where does the energy go?
What you may be missing here is that the photon doesn't acceerate up to C like a car accelerating up to highway speed. At the instant of release, it is traveling at C. The "recoil" is therefore also an instantaneous change in energy. A photon doesn't undergo "changes" when it is emitted.
 
  • #109
omin said:
I get it from this simple equation.

KE = 1/2 m * v ^2

where m = mass of photon

v = speed of photon (velocity has direction, which is included in the energy equation.)

OK, so where are you getting that from?

That equation does not apply to photons. Firstly, it only applies to particles with mass (which photons don't). Secondly, it doesn't even apply to massive bodies if the speed v is comparable to c (and in the case of photons, the speed is c).

Therefore, if photon mass is consistent, a change in speed changes photons energy. If the photon doesn't change speed, then does it's mass change during recoil?

Since this is predicated on the above misconception, I have no answer for you.

If the photon doesn't change speed or mass during recoil, then where does the energy go? Conservation of energy represents that a change of energy on one side of the equation is proportionate to the other side of the equation, where one side is a atom and it's property recoil and the other is a photon emission.

I already told you: The photon energy is proportional to its frequency. For photons: E=hf (h=Planck's constant, f=frequency).

If an instrument senses recoil, for us to know the instrument senses recoil, we have to sense the instrument sensing recoil. If we know it sensed it, we indirectly sense recoil. Instrument aided sense. All sense is indirect really, we don't sense the objects we sense a piece of the chain of a chain reaction. I'm basing this on the fact that thought or sense of a physical object is an expression of the object rather than the object. Which assures me, we've sensed the photon, because it has mass. Without mass, it sends no expression properties of its existence.

The instrument doesn't aid our senses, it is replaces them. There is no such thing as "indirect sensation". Sensations are direct, first person experiences. But now we're talking philosophy again.
 
  • #110
BobG said:
where [tex]F_s[/tex] is solar pressure or 1367 W/m^2.
c is speed of light
m is mass of satellite
q is reflectivity (1 for totally reflective, 0 for totally absorbant)
i is incidence angle

OK, now I can tell you about (1+q). If a photon is absorbed by a body and never heard from again, then it transfers all its momentum to the body. This would correspond to q=0. This is a highly idealized state of affairs that is not realized in practice, but q=0 can be approached and it serves as a lower bound. Now for the other extreme: the photon is absorbed, and then promptly re-emitted in the exact opposite direction. The momentum change of the photon is not p, but 2p. This would correspond to q=1, which gives us a multiplier of 2 for the force on the body.
 
  • #111
omin said:
I get it from this simple equation.

KE = 1/2 m * v ^2

where m = mass of photon

v = speed of photon (velocity has direction, which is included in the energy equation.)

Therefore, if photon mass is consistent, a change in speed changes photons energy. If the photon doesn't change speed, then does it's mass change during recoil?

If the photon doesn't change speed or mass during recoil, then where does the energy go? Conservation of energy represents that a change of energy on one side of the equation is proportionate to the other side of the equation, where one side is a atom and it's property recoil and the other is a photon emission.

Please explain that equation. I'm not sure if it infers the photon has change in it's mass or velocity when the atom in the equation appear to.



If an instrument senses recoil, for us to know the instrument senses recoil, we have to sense the instrument sensing recoil. If we know it sensed it, we indirectly sense recoil. Instrument aided sense. All sense is indirect really, we don't sense the objects we sense a piece of the chain of a chain reaction. I'm basing this on the fact that thought or sense of a physical object is an expression of the object rather than the object. Which assures me, we've sensed the photon, because it has mass. Without mass, it sends no expression properties of its existence.

A photon has no mass. So the equation for finding the kinetic energy of an object of mass doesn't apply.

You need to use this equation:

[tex]E=\frac{hc}{\lambda}[/tex]
where E = energy

c = speed of light (2.9979 x 10^8)
h = Planck's constant (6.626 x 10^-34)
and [tex]\lambda[/tex]= wavelength

An alternative version is to use the frequency. Frequency is speed of light (corrected) divided by the wavelength. Energy is then Planck's constant times frequency.

The higher the frequency, the more energy. (or, the shorter the wavelength, the more energy)

Edit: Oops. Thinking faster than I could type.
 
Last edited:
  • #112
Tom Mattson said:
OK, now I can tell you about (1+q). If a photon is absorbed by a body and never heard from again, then it transfers all its momentum to the body. This would correspond to q=0. This is a highly idealized state of affairs that is not realized in practice, but q=0 can be approached and it serves as a lower bound. Now for the other extreme: the photon is absorbed, and then promptly re-emitted in the exact opposite direction. The momentum change of the photon is not p, but 2p. This would correspond to q=1, which gives us a multiplier of 2 for the force on the body.

Right. I'm with you so far.

But, now, something should happen to the light when it is re-emitted in the opposite direction. If the light moved the mirror, then it seems like the light should lose some energy. In other words, the frequency of the reflected light would seem to have to have a lower frequency than the original received light.
 
  • #113
BobG said:
Right. I'm with you so far.

But, now, something should happen to the light when it is re-emitted in the opposite direction. If the light moved the mirror, then it seems like the light should lose some energy. In other words, the frequency of the reflected light would seem to have to have a lower frequency than the original received light.

You're right. I failed to mention that q=1 is also an idealized case that is not realized in practice, but that it can be approached and that it is an upper bound.
 
  • #114
Do reflected photons lose energy?

BobG said:
But, now, something should happen to the light when it is re-emitted in the opposite direction. If the light moved the mirror, then it seems like the light should lose some energy. In other words, the frequency of the reflected light would seem to have to have a lower frequency than the original received light.
Tom Mattson said:
You're right. I failed to mention that q=1 is also an idealized case that is not realized in practice, but that it can be approached and that it is an upper bound.
Right, q=1 represents the case of an ideal reflector. But I don't think that this formula that BobG produced addresses his real concern, which is conceptual.

I think BobG is asking: Isn't it true that the reflected photons must lose energy? After all, they produce a radiation pressure on the reflecting surface, thus do work on the surface, thus supply energy to it. That energy must come from somewhere. If the photons reflect back with the same frequency as before, then something's fishy. (Is that an accurate statement of your reasoning, BobG?)

That reasoning looks good to me. I would say that the reflected photons must be redshifted (however slightly) compared to their original frequency. Comments? Am I missing something?
 
  • #115
Yes, exactly.

Also, I take it that all the photons are absorbed by atoms in the surface of the object being struck. The difference between being converted to heat (increasing the motion of the atoms in a random pattern) vs. being reflected is just because of the direction the photons are re-emitted.

(I've got to read something on this, this has kind of got my curiosity up - especially if you go another step further and start substituting transparent or translucent surfaces for the 1 in 1+q).
 
  • #116
Doc Al said:
That reasoning looks good to me. I would say that the reflected photons must be redshifted (however slightly) compared to their original frequency. Comments? Am I missing something?
Its awful, but I don't know this one either. It seems like a situation where momentum is conserved but energy isn't. Maybe its just a matter of not taking into account mass differences, ie we tend to not think about how much velocity an individual photon will give to something with mass it hits.

Thinking about billiards balls, in a collision between a moving one and a stationary one, the moving one stops. What if the stationary one were larger than the moving one? The moving one bounces back, right? Taking the limit, if the stationary ball is almost infinitely large, it doesn't move much and the moving ball bounces back with almost the same speed/energy as it started with. Since light can't travel at almost C, it must be very, very, very slightly redshifted. Seems like maybe we just oversimplify and get rid of the "almost."

Am I close?
 
Last edited:
  • #117
Tom Mattson said:
The instrument doesn't aid our senses, it is replaces them. There is no such thing as "indirect sensation". Sensations are direct, first person experiences. But now we're talking philosophy again.


They call it physics because only physics can be sensed, the rest is religion and philosophical psychological order (pure theory).

If you say we don't sense the photon, then it's not physics. It's pure psychological mass in the brain.

Be aware, you are the one who is claiming I'm the philosopher, but you claim theories come from nonsense, which is no physical origin.

It's clear I"m after the physics here, which is only the senseable stuff!
 
  • #118
omin said:
They call it physics because only physics can be sensed, the rest is religion and philosophical psychological order (pure theory).

They call it physics because it's the study of things that exist. These things need not be sensed to be known. A detector whose workings are known is a valid substitute.

If you say we don't sense the photon, then it's not physics.

Wrong. Every day physicists do experiments with photons that are never sensed by humans. The detector registers their presence, and that is sufficient.

It's pure psychological mass in the brain.

What is "psychological mass"?

Be aware, you are the one who is claiming I'm the philosopher,

I said that you were drifting off into philosophy, but not that you are a philosopher. You've got a long way to go before you could be called a philosopher.

but you claim theories come from nonsense, which is no physical origin.

I never claimed that theories come from nonsense, nor did I claim that they come from "no physical origin". That's just your strawman argument.

It's clear I"m after the physics here, which is only the senseable stuff!

It's clear that you don't understand what you're talking about.

Anyway, do you have anything to say about the other corrections I made to your post? For instance, about the kinetic energy of the photon?
 
  • #119
BobG said:
A photon has no mass. So the equation for finding the kinetic energy of an object of mass doesn't apply.

You need to use this equation:

[tex]E=\frac{hc}{\lambda}[/tex]
where E = energy

c = speed of light (2.9979 x 10^8)
h = Planck's constant (6.626 x 10^-34)
and [tex]\lambda[/tex]= wavelength

The word order above are representations of thoughts. Thoughts only represent senses. Senses only represent the physically objective world. The physically objective world consists of either thought of the objective world or thought of thought existing in the mind (the subjective physical world). Therefore, these symbols are representation of physics of the objective world or they or only a theory of the mind which does not represent the objective world accurately.

What I have said is not philosophy, it's the basis of what we call theory that all physicists must understand to represent the physical world accurately.

Mass represents anything physical or a property of something physical. Or is mass also a theory existing in the mind that is outside the valid representation of the physical world?

If you guys undermine valid physical theory by asserting psychological order that represent no physics of the world is valid physics, then it's not physics and we can't talke senseably about this.
 
  • #120
omin said:
The word order above are representations of thoughts. Thoughts only represent senses. Senses only represent the physically objective world. The physically objective world consists of either thought of the objective world or thought of thought existing in the mind (the subjective physical world). Therefore, these symbols are representation of physics of the objective world or they or only a theory of the mind which does not represent the objective world accurately.

If we can at least agree that things that are detected by measurement apparatus (as opposed to direct sensation) constitute knowledge of the physical world, then we can move on from this issue of "sensing" and get back to your misconceptions about the kinetic energy of photons.

What I have said is not philosophy,

It very obviously is philosophy. You are defining what it means to be physical, to be objective, to be a representation of the physical world, and you are demarcating the line between the mind and the physical. That's metaphysics through and through. And your earlier comments on how sensation is prerequisite to knowledge of the physical universe is very clearly an epistemological theory. If this isn't philosophy, then nothing is.

it's the basis of what we call theory that all physicists must understand to represent the physical world accurately.

The theories that physicists develop to represent the world are already known to be accurate because they match measurements so well. The proof of the pudding is in the eating.

Mass represents anything physical or a property of something physical. Or is mass also a theory existing in the mind that is outside the valid representation of the physical world?

What difference does it make? If mass is a property of physical objects, then we can formulate physical theories in terms of it. What you are doing here is pondering the metaphysical meaning of "mass", which is a philosophical tangent issue.

If you guys undermine valid physical theory by asserting psychological order that represent no physics of the world is valid physics, then it's not physics and we can't talke senseably about this.

Will you please stop spouting off your opinions about who is undermining what theory until you demonstrate that you have mastered the theories yourself? You are still hung up on some very basic issues and you would benefit the most from getting those cleared up, rather than doing all this philosophizing (there's that word again) on things you clearly do not understand.
 
  • #121
Tom Mattson said:
Will you please stop spouting off your opinions about who is undermining what theory until you demonstrate that you have mastered the theories yourself? You are still hung up on some very basic issues and you would benefit the most from getting those cleared up, rather than doing all this philosophizing (there's that word again) on things you clearly do not understand.

Physical theory has no contradictions;there may only be categories of existence, which may be compared to arrive at categorization and quantification. Physics is very, very, very little the Boolean exist or don't exist misrepresentation. It's here or there and how much in comparison to this much of what's over here. We may only speak what exists, that's physics and when we reach the limit of our senses and our physically derived probabilities diminish in positive value, we say I don't know.

If a thing has no mass(boolean!), it may not have the property distance. If it doesn't have the property distance, it may not have the property speed. If it doesn't have the property speed, it may not have the property acceleration. So, if not mass, none of these may derived. If none of these may be derived, nor can energy be represented. (To arrive at a rate of speed, you must sense what is speeding.) Without acceleration (what happens when we mean force) an object is outside our sense because there is lack of contact; therefore you do not know that it exists or will never know it exists unless contact occurs, which demands the absolute prerequisite mass. Knowledge depends upon mass and velocity, and finally contact (force). Have you ever been hit, by only, and I emphasize only, the velocity of the sun? Mass is absolutely necessary for a change in velocity or (action and reaction) to occur.

To assert the thought of phenomenon c, you must use the basic physical theories that build up to the point that allow us to begin to think about phenomenon c. Fundamental concepts necessary to arrive at the thought of phenomenon c are atleast mass, speed, velocity and acceleration. These concepts are absolutley necessary to get to the concept c, so c depends upon them. Once we arrive at the discussion c (or energy), saying authoritively, "you may now not use the theory we used to arrive here", is self-negating. You may build the pyramid, but if you destroy the base, the peak comes down with it.

In calling this a philosophical point is accuarate, but it's more accurate that it's physics in this discussion, because it's expressive of the principle in N III Law as it relates to the physical phenomena in which we are discussing.

There is but one road to c and it is through Newton.
 
  • #122
The displacement effect the light has on the satelite occurs during:
1. the light impact
2. during photon absorbtion
3. during photon manifestation
4. during photon emision
5. or some mix?

russ_watters said:
Thinking about billiards balls, in a collision between a moving one and a stationary one, the moving one stops. What if the stationary one were larger than the moving one? The moving one bounces back, right? Taking the limit, if the stationary ball is almost infinitely large, it doesn't move much and the moving ball bounces back with almost the same speed/energy as it started with. Since light can't travel at almost C, it must be very, very, very slightly redshifted. Seems like maybe we just oversimplify and get rid of the "almost."

Can a change in frequency of light and the mass of the object from which the light reflects be used as variables to attempt to give us the mass of light? If you believe light has no mass, I've heard the lecture, nevermind, unless of course you have a more convincing lecture.

pmb_phy said:
No matter what the final speed of the atom, the final speed of the photon is always the same, c. All that is different for photons with different momentum is the energy of the photon. The speed of the atom, however, is a function of the atoms final proper mass (the proper mass of the atom must have decreased in this process) and the atom's momentum.

The matter of an atom decreases proportionate to the energy of a photon it emits. Matter is neither created nor destroyed. Therefore, the photon represents this difference in matter of the atom?

An Instataneous C?
Clearly, things are touching other things in this circumstance(N III Law), where photons emit from atoms and the atoms recoil. The photon manifests in an atom that has a velocity less than c (unless inner structural elements are already at c). There appears to be elements in a state of pre-photonic form in the atom. In the process of manifesting a photon, things must be accelerated into form, since they are in pre-photonic form, not yet a photon. Formation requires N III Law, unless the photon's inertia in this example is entirely unaffected and the whole process is determined and occurs without acceleration. Once the photon is a photon, it is said to have instantaneous c. To claim instataneous state c is justified only as a state. All states before the photon instantaneous c state then must be acceleration states? Meaning photon forming states.

How can all the elements that collapse form and reform during this process always be separate, in an isolated inertia?

If photon from atom separation is instataneous and the photon is instataneously at c, it either moves away from the instataneious velocity of the atom at separation at c, moves along the aether at c, moves along some other resistive field at c, or (instant c means instant intertia) moves based upon it's own physical dimensions at c (which would be determined by the atom!)
 
  • #123
Omin,

Are you an antique book collector? I'm thinking the last book printing your theory came out sometime before 1910 at the latest.
 
  • #124
Omin,

If you had a point to your last post to me, you have successfully hidden it by couching it in gibberish. The only thing intelligible enough to comment on is this:

omin said:
There is but one road to c and it is through Newton.

Do you mean "there is but one means to derive the invariance of the speed of light"? If so, then you are wrong. Einstein derived it from the covariance of Maxwell's equations (not any of Newton's laws).
 
  • #125
That's okay guys. Whatever.

Explanation requires competence. You are either competent enough to explain things from my so called primitive 1910 understanding or not. If it's so primitive, why is it so hard to explain? Having trouble with simple things are ya?

So far, I've gained very little from the discussion, and that is the positive amount. The ability to convey things to someone interested in this forum has been demonstrated. Some things have been conveyed. But, it's been unnecessarily cluttered with loads of insults and incompetent explanation. I'm less likely to respond to you now. I resent being taunted into idiotic insult games through your pompous tones in your responses. Not that I've never been involved in it my life, but it's cleary understood by me to be the defense mechanism of intellect weakness and have never been a efficient use of time, except the time it took to end it. I'm here to have attention to those who have respect for the discipline and have respect for those who are seeking an understanding of the discipline.

You can write what you want but I'd rather you not respond to my posts unless your ready to be serious and express some repsect to those who may stand on your shoulders, since you claim you are further ahead. That means stop being a "Mr. I Know Everything, You Don't Know What Your're Talking About and your 'You are Gibbering Claims'" and begin debate that gets somewhere. People don't walk into a classrom because they know everything thing. Did you know that? You proved you haven't been aware of that by your attitude toward me! I'll debate and try to understand, but I'm finished with this riduculous tone. If it behooves you to keep it up, I'll just ignore you.

And, furthermore, I'm intelligent enough to know this is valuable to you.
 
  • #126
What do you mean by invariance?
 
  • #127
omin said:
What do you mean by invariance?
A key property of light is that its speed is invariant, meaning that it has the same value as measured in any inertial frame.
 
  • #128
omin said:
Explanation requires competence.

So does learning.

You are either competent enough to explain things from my so called primitive 1910 understanding or not. If it's so primitive, why is it so hard to explain? Having trouble with simple things are ya?

I've got a news flash for you: A great deal of the responsibility for your education falls to you. You would do well to lose this attitude of "If you can't spoon feed this to me in terms that I can understand, then you aren't competent at explaining physics". Not only will it exasperate anyone who tries to help you, but it means that you are shirking your responsibility to yourself as one who claims to be serious about learning.

So far, I've gained very little from the discussion, and that is the positive amount.

Well then look in the mirror. You get out what you put in. That has always been true, and it always will be true.
 

Similar threads

Back
Top