Is Planck's constant the key to understanding a quantum?

[trogan]

Is there a standard, agreed on definition of a Quantum in physics ?

Also, I have picked up this information about a quantum on the internet (http://www.peterrussell.com/SG/Ch5.php" ). Does this correctly describe Plank's constant and its relation to a quantum ?

"Although the amount of energy in a photon varies enormously, there is one aspect of the quantum that is fixed. Each and every quantum has a constant amount of action.

Mathematicians define action as an object’s momentum multiplied by the distance it travels; or the object’s energy multiplied by the time it is traveling–the two are equivalent. The amount of "action" in a ball thrown across a football field, for example, would be greater than the same ball thrown half the distance. Double the ball’s mass, and you double the action. Or imagine yourself running at a constant rate of energy output. If you run for twice as long, there will be twice the action–which makes intuitive sense.

The actual amount of action in a quantum is exceedingly small, about 0.00000000000000000000000000662618 erg.secs (or 6.62618x10-27 erg.secs in mathematical shorthand)–but it is always exactly the same amount.

This is called Planck’s constant (after its discoverer). It is the second universal constant to emerge from modern physics. Like the first–the speed of light–it is a constant of light. Light always comes in identical units of action.
"

 

[Vanadium 50]

Quantum is an adjective, not a noun. So you won't find a universal definition of "a quantum" any more than you will find a universal definition of "a blue" or "a slow".

 

[trogan]

Quantum is an adjective, not a noun. So you won't find a universal definition of "a quantum" any more than you will find a universal definition of "a blue" or "a slow".

Not according to the dictionaries I have visited.

For example, from the Free Dictionary:

quan·tum (kwntm)
n. pl. quan·ta (-t)
1. A quantity or amount.
2. A specified portion.
3. Something that can be counted or measured.
4. Physics
a. The smallest amount of a physical quantity that can exist independently, especially a discrete quantity of electromagnetic radiation.
b. This amount of energy regarded as a unit.
adj.
Relating to or based upon quantum mechanics.

 

[DaveC426913]

So don't use the Free Dictionary...


Quantum means, generally: discrete. A quantum leap is a discrete leap.

 

[SimonA]

For what it's worth, my definition of quantum would include the word "step". It's all about a step change, it's about being on this step and not the other. When we understand quantum properly, I reckon step will be a usefull word to use.

 

[trogan]

So don't use the Free Dictionary...


Quantum means, generally: discrete. A quantum leap is a discrete leap.

Then there is "quantum of light" or "light quantum" where it is definitely used as a noun. It is the definition of the noun that interests me. I have books on physics where neither it nor Planck's constant are defined and I thought to myself I wonder why and whether physicists work with standard definitions of these two entities at all ?

 

[SimonA]

Excellent point. I would contend that a photon is the result of an atoms energy level reaching the top step(ie no longer on the steps and free to travel elsewhere)

 

[Born2bwire]

Excellent point. I would contend that a photon is the result of an atoms energy level reaching the top step(ie no longer on the steps and free to travel elsewhere)

The "top step" as you put it of an atom would be the ionization energy, when the bounded electron is freed from the atom's orbitals. Photon emission does not require any such phenomenon, photons are emitted from atoms when an electron drops down from a given excited state to a lower state.

I would also throw my hat into the "quantum = discrete" ring. In general, one of the defining properties of quantum mechanics is the quantization of modes as opposed to the continuous spectrum of modes that exist for classical physics. This meaning can also be applied to the specific examples where we use quantum/quanta as well. For example, photons are the quanta of the electromagnetic wave. Thus, when physicists talk about the light quanta, they are talking about the discrete packets of light, the photons.

 

[Vanadium 50]

If you are trying to learn physics from a dictionary, you have a difficult - probably impossible - job ahead of you.

If you are trying to learn anything at all without discarding your preconceptions, you have an even more difficult job ahead of you.

 

[Vanadium 50]

Excellent point. I would contend that a photon is the result of an atoms energy level reaching the top step(ie no longer on the steps and free to travel elsewhere)

There is no top step. The inverse square law has an infinite number of bound states.

 

[trogan]

Quantum is an adjective, not a noun. So you won't find a universal definition of "a quantum" any more than you will find a universal definition of "a blue" or "a slow".

I will settle for a definition of the adjective. Does Physics have a standards body that oversees that sort of thing ?

It is weird. The description of Quantum Mechanics on Wiki does not say what "Quantum" means. And it seems wherever I look the Quantum seems to rate little or no mention when dealing with Quantum Theory. Has it been misnamed ?

 

[Mentz114]

Excellent point. I would contend that a photon is the result of an atoms energy level reaching the top step(ie no longer on the steps and free to travel elsewhere)

Not so. A photon is emitted when the electron drops to a lower energy level. This can happen spontaneously even if the electron is only 1 step above its ground state.

See any elementary text on quantum mechanics.

 

[trogan]

Actually, there IS a very satisfying definition of a quantum on WIKI:

"In physics, a quantum (plural: quanta) is the minimum unit of any physical entity involved in an interaction. An example of an entity that is quantized is the energy transfer of elementary particles of matter (called fermions) and of photons and other bosons. The word comes from the Latin "quantus", for "how much." Behind this, one finds the fundamental notion that a physical property may be "quantized", referred to as "quantization". This means that the magnitude can take on only certain discrete numerical values, rather than any value, at least within a range. There is a related term of quantum number.

A photon, for example, is a single quantum of light, and may thus be referred to as a "light quantum". The energy of an electron bound to an atom (at rest) is said to be quantized, which results in the stability of atoms, and of matter in general.

As incorporated into the theory of quantum mechanics, this is regarded by physicists as part of the fundamental framework for understanding and describing nature at the infinitesimal level, for the very practical reason that it works. It is "in the nature of things", not a more or less arbitrary human preference.
"

 

[Feldoh]

I have a question for the OP. Now that you have a supposed definition of "quantum" do you feel any smarter?

Have you learned anything that has built up your physical intuition?

Probably not. My point is is that learning definitions is not what you should be focused on it you want to understand physics. A rose by any other name would still smell as sweet, and all that...

 

[trogan]

I have a question for the OP. Now that you have a supposed definition of "quantum" do you feel any smarter?

Have you learned anything that has built up your physical intuition?

Probably not. My point is is that learning definitions is not what you should be focused on it you want to understand physics. A rose by any other name would still smell as sweet, and all that...

Define "smarter" !

Seriously, I am quite satisfied with what I have achieved here and thank you for your advice.

 

[trogan]

It seems then that a quantum is a discrete amount of energy. Can someone tell me then how Quantum Physics came to be mainly about waves in various forms ? Would Wave Physics better describe the reality ?

 

[trogan]

It seems then that a quantum is a discrete amount of energy. Can someone tell me then how Quantum Physics came to be mainly about waves in various forms ? Would Wave Physics better describe the reality ?

Also, it would seem that (for example) a photon and an electron are the same deal in one respect in that they both have the same "action" potential (as given by Planck's constant). The big difference between the two (as far as the quantum of energy each contains) seems to be the rate at which they vibrate. This is my extremely hard-won understanding. Is it correct ?

This seems to me to strongly point to elementary particles at least being composed of photons with some attributes changed.

 

[Vanadium 50]

This seems to me to strongly point to elementary particles at least being composed of photons with some attributes changed.

Trojan, you are flying towards crackpottery at a million miles an hour. I suggest you slow down and change direction. Yesterday you didn't know if the word "quantum" meant. Today you are saying that people who have studied quantum mechanics for decades have their models all wrong.

 

[DrChinese]

Would Wave Physics better describe the reality ?

The name is fine as is. As Vanadium 50 says, you might want to spend a additional time learning about some of the quantum concepts, reasoning and experimental support before trying to come up with improved names. Everyone starts out with lots of questions and hunchs, and these are mostly addressed in introductions to the subject. So you will learn about things like wave/particle duality. There have probably been 250,000+ papers/experiments published on QM since inception, so please be cognizant that the premises have been studied and examined in great detail by a lot of people.

 

[trogan]

The name is fine as is. As Vanadium 50 says, you might want to spend a additional time learning about some of the quantum concepts, reasoning and experimental support before trying to come up with improved names. Everyone starts out with lots of questions and hunchs, and these are mostly addressed in introductions to the subject. So you will learn about things like wave/particle duality. There have probably been 250,000+ papers/experiments published on QM since inception, so please be cognizant that the premises have been studied and examined in great detail by a lot of people.

I am a long way from being a novice. I have many books on the subject (for example Quantum Reality by Nick Herbet and The Emporer's New Mind by Roger Penrose). I understand the concepts reasonably well. The maths I only seek to understand if I really need to. I am totally aware that some of the things I talk about will be naive. I try and limit my questions on Physics Forum to those I cannot find answers to in my books and searches.

My deeper understanding of the quantum as expounded here only came in recent days, yet I have studied Quantum Mechanics for years. Ditto for Planck's Constant. I hope other novices like myself will benefit from it as it is as rare as hen's teeth elsewhere.

I wonder why no one gave me a definition of a quantum. I am guessing the question seemed trivial.

 

[trogan]

Trojan, you are flying towards crackpottery at a million miles an hour. I suggest you slow down and change direction. Yesterday you didn't know if the word "quantum" meant. Today you are saying that people who have studied quantum mechanics for decades have their models all wrong.

I had a fairly good idea what quantum meant. I was after a definition that would verify what I thought. I am not saying quantum mechanical models are all wrong. Heck I am not THAT naive.

What I would really like from you and other experts like yourself is answers to my questions. I thought I gave a good account of why an electron and a photon are similar quantum-wise. So what is wrong with my statement that: "This seems to me to strongly point to elementary particles at least being composed of photons with some attributes changed" ?

 

[DaveC426913]

What I would really like from you and other experts like yourself is answers to my questions...


So what is wrong with my statement that..."This seems to me to strongly point to elementary particles at least being composed of photons with some attributes changed" ?

Because your statement is not a question?

 

[trogan]

Because your statement is not a question?

Hokay, I will rephrase it:

"Given that what I have just said is true, does this point to elementary particles (at least) being composed of photons with some attributes changed"

I don't like to seem ungrateful but this thread has been pretty tortuous form my point of view and none of my questions to date have been answered. Are you trying to discourage me (don't blame you ... being a software developer I can be annoyingly pedantic) ?

 

[DaveC426913]

"Given that what I have just said is true, does this point to elementary particles (at least) being composed of photons with some attributes changed"

Two things sharing a property does not mean they are the same thing.

"Java and JavaScript share a similar name, it seems to me therefore that they are probably the same language with some syntactical differences."

I don't like to seem ungrateful but this thread has been pretty tortuous form my point of view and none of my questions to date have been answered. Are you trying to discourage me (don't blame you ... being a software developer I can be annoyingly pedantic) ?

I am a software developer as well. There is nothing wrong with being pedantic. The resistance you're encountering is due to the fact that you are putting forth unfounded hypotheses and then asking for validation of them. You will get nowhere fast.

If you want to get answers about how the world works, then ask questions about how the world works.

 

[trogan]

Two things sharing a property does not mean they are the same thing.

An apple and a firetruck are both red but that does not mean they are the same thing.

It is the fact that both an electron and a photon have the same action potential that intrigues me. This seems to me to indicate an extraordinarily strong connection between the two.

And you should know from software development that you can have two objects of type X with different attributes yet each is still behaves as a type X object.

 

[Born2bwire]

What action potential?

 

[trogan]

What action potential?

See my first post: "Each and every quantum has a constant amount of action".

I have shortened it to action potential. It seems like a good description and there no others around that I can ascertain.

 

[DaveC426913]

And you should know from software development that you can have two objects of type X with different attributes yet each is still behaves as a type X object.

Yes you can. But does that mean ALL things behave that way such that it would make a good general principle to imagine how any old thing works?

 

[Born2bwire]

See my first post: "Each and every quantum has a constant amount of action".

I have shortened it to action potential. It seems like a good description and there no others around that I can ascertain.

What action potential?

 

[trogan]

What action potential?

alrighttt, ditch Action Potential ! ... pity I thought it quite evocative (although potential action would have been better - in line with potential energy). Instead replace it with Quantum Unit of Action (i.e Planck's Constant h). This seems to be the generally agreed on expression.

Therefore is my understanding of this unit correct ? Namely that all energy quanta have the same unit of action and this is related to the energy via the equation E = hf.

 

[Feldoh]

I don't know what you're saying but...

Planck's constant is simply a proportionality constant between the energy and frequency of a photon in the way you're trying to use it.

It's a number that is always equal to E/f for a photon.

 

[trogan]

I don't know what you're saying but...

Planck's constant is simply a proportionality constant between the energy and frequency of a photon in the way you're trying to use it.

It's a number that is always equal to E/f for a photon.

See my first post.

My understanding is that it is the Unit of Action of a Quantum of Energy. Maybe it could be called "oomph" ! It is applicable not only to photons but to ANY particle containing energy (all of them ?). It stands by itself as a unit.

It is the very basis of Quantum Mechanics and I am guessing if you (like I used to) think of it as E/f then your understanding of Quantum Physics is not as deep as it could be (I am willing to be shot down in flames on this statement !).

 

[SimonA]

Sorry - I agree "top step" was not the best description. Maybe "top of the step" is ? The discreet entity is like integers, the remainder exists in a different form, hence photon emmision ?

 

[SimonA]

Sorry that's even worse...

What do you people think orbital shells represent ? Explain them to me in a way that's based on reasoned thought, rather than assumption based on results...

 

[Vanadium 50]

then your understanding of Quantum Physics is not as deep as it could be (I am willing to be shot down in flames on this statement !).

I repeat my recent comment - you are headed towards crackpottery at a million miles an hour. You're a QM novice. Nothing wrong with that; we all were at one time. But now you're now telling other people that they are doing it wrong and/or don't understand it. You really need to base this kinds of judgments on expertise, and you haven't put the effort into developing this expertise.

I highly recommend Steve Dutch's essay on http://www.uwgb.edu/dutchs/PSEUDOSC/SelfApptdExp.htm"

The resistance you're encountering is due to the fact that you are putting forth unfounded hypotheses and then asking for validation of them. You will get nowhere fast.

If you want to get answers about how the world works, then ask questions about how the world works.

Exactly.

Explain them to me in a way that's based on reasoned thought, rather than assumption based on results...

"Sit! Beg! Roll Over! Play Dead!"

You might think about using a little friendlier language than barking orders at the rest of the membership. It might put people in a better mood for replying.

I'm trying not to close this thread - but thus far, it's virtually entirely about unfounded hypotheses (and I have had to remove a number of messages). Please everyone, take a look at the PF Rules on overly speculative posts.

 

[trogan]

I repeat my recent comment - you are headed towards crackpottery at a million miles an hour. You're a QM novice. Nothing wrong with that; we all were at one time. But now you're now telling other people that they are doing it wrong and/or don't understand it. You really need to base this kinds of judgments on expertise, and you haven't put the effort into developing this expertise.

I highly recommend Steve Dutch's essay on http://www.uwgb.edu/dutchs/PSEUDOSC/SelfApptdExp.htm"





Exactly.



"Sit! Beg! Roll Over! Play Dead!"

You might think about using a little friendlier language than barking orders at the rest of the membership. It might put people in a better mood for replying.

I'm trying not to close this thread - but thus far, it's virtually entirely about unfounded hypotheses (and I have had to remove a number of messages). Please everyone, take a look at the PF Rules on overly speculative posts.

I am not exactly a novice. Well-informed amateur would be a better way of putting it. I have had an interest in QP for years and I am also an industrial chemist (prior to software development). Apart from a speculation about protons being the basis of matter I was under the impression that what I was saying was just mainstream QP. Noone has been taking issue with what I have been saying (at least with specifics) so I have been encouraged to keep going. I do have as my bible a book "Quantum Reality" by Nick Stevens which gives an eye-opening explanation of the quantum.

Please, if you have issues with what I am saying, tell me specifically. This is my purpose in being on PF.

As far as "Sit! Beg! Roll Over! Play Dead!" is concerned, I will take what you say on board and try and come across in a more friendly fashion. I certainly don't intend to be unfriendly and I REALLY appreciate the people on PF who are helping me. One of the problems I have is I sometimes don't know the expertise level of people I am replying to and thus can gear
my reply accordingly. I suspect this is a problem for many people.

It might be presumptuous of me to say this but I really do believe that what I have been saying is mainstream QP and if you don't agree then I would love to hear why.

 

[trogan]

I highly recommend Steve Dutch's essay on http://www.uwgb.edu/dutchs/PSEUDOSC/SelfApptdExp.htm"

I have read Steve Dutch's essay and agree with what he says - even if he does set himself up as a an expert on Self-Appointed Experts without, it would seem, psychology qualifications (insane grin ... can't get one on drop down). I do think he needs to chill somewhat ! I will try to phrase my posts accordingly - and chill, of course.

 

[ZapperZ]

Apart from a speculation about protons being the basis of matter I was under the impression that what I was saying was just mainstream QP.

So which part of "mainstream QP" did you get this from?

There is a difference between wanting to learn, and pretending that one knows enough to respond to a post as if one is giving a standard, acceptable answer. I can only guess that you know the difference between the two and can see that you, in fact, have done the latter. If you want to learn something, ASK. If you are not an expert in a particular subject, try to refrain yourself from offering an answer and defer to those who are. Providing a confusing, and often wrong answer is NOT learning something. All it does is decrease our signal-to-noise ratio, in which many of us will have to correct. The task of addressing the original question can be difficult enough. We don't need the added burden of correcting the offered answers as well.

Zz.

 

[trogan]

So which part of "mainstream QP" did you get this from?

Zz.

My "bible" is Quantum Reality by Nick Herbet. I have a number of other books that I use as reference mostly geared to non-physicists.

Also internet searches (lots), for example http://en.wikipedia.org/wiki/Quantum" . I can retrieve them from history if you want to know them but at least half I would say are authoritative.

Also PF itself of course although I have forgotten exactly which threads.

 

[trogan]

So which part of "mainstream QP" did you get this from?

If you want to learn something, ASK.
Zz.

Believe me I have been asking, pleading almost ! My original post was to ask for the definition of a quantum and also to verify a description of Planck's Constant that I had come across on the internet. NONE of my questions have been answered which really puzzles me. What then happens is that I do a bit more study and come up with an answer myself which I then post and ask is it correct.

 

[trogan]

All it does is decrease our signal-to-noise ratio, in which many of us will have to correct.
Zz.

Thanks for informing me of the difficulty of your task. I will be a lot more careful about my posts in future.

 

[ZapperZ]

My "bible" is Quantum Reality by Nick Herbet. I have a number of other books that I use as reference mostly geared to non-physicists.

Also internet searches (lots), for example http://en.wikipedia.org/wiki/Quantum" . I can retrieve them from history if you want to know them but at least half I would say are authoritative.

Also PF itself of course although I have forgotten exactly which threads.

Can you quote exactly where your "bible" actually claims that protons being the basis of matter? I mean, how in the world does one reconcile the existence of leptons? Besides, how would you know what you read in there is part of "mainstream physics"? After all, a pop-science book can easily be speculating something that isn't accepted yet (example: Brian Greene's "Elegant Universe").

You need to keep in mind that you might have a faulty understanding of what you read, or that you didn't get the complete picture. It is why you shouldn't be so quick at offering someone an answer.

Zz.

 

[trogan]

Can you quote exactly where your "bible" actually claims that protons being the basis of matter? I mean, how in the world does one reconcile the existence of leptons? Besides, how would you know what you read in there is part of "mainstream physics"? After all, a pop-science book can easily be speculating something that isn't accepted yet (example: Brian Greene's "Elegant Universe").

You need to keep in mind that you might have a faulty understanding of what you read, or that you didn't get the complete picture. It is why you shouldn't be so quick at offering someone an answer.

Zz.

Here is a review of my "bible" on Amazon ... from a physicist:

"This book is, without a doubt, one of the best nontechnical physics books I have read. As a kid in high school, this book was my first introduction to the mysterious world of quantum physics. I was amazed that, despite my technical illiteracy, Herbert gave me both insight into the inner mathematical workings of quantum mechanics, and into the deeply troubling conceptual problems that this radical theory forces upon us. Even today, as a graduate student in theoretical physics, I have a more profound appreciation for quantum mysteries than any of my classmates, simply because I read this book in high school. I would recommend this book for the layperson and the quantum field theorist alike!"

There is no mention in it of protons being the basis of matter. I have said that this is pure speculation on my part and I don't want an answer on it. Like most of my speculations it will most likely turn out to be just that ! I am sorry I raised it.

You need to keep in mind that you might have a faulty understanding of what you read, or that you didn't get the complete picture. It is why you shouldn't be so quick at offering someone an answer.

Zz.

With QP the chance of this happening is obviously extremely high. I do think long and hard about what I say and I try and couch my language in words like "seem" and "guess" to make sure that the reader is aware that I am not offering what I say as "gospel".

For example the full sentence of a statement you have criticised me for is:

"It is the very basis of Quantum Mechanics and I am guessing if you (like I used to) think of it as E/f then your understanding of Quantum Physics is not as deep as it could be (I am willing to be shot down in flames on this statement !).".

I do say twice in it that I am not sure of my facts.

 

[Physics Monkey]

Hi trogan,

I'll take a stab at some of your questions.

1. I am not aware of anybody that regulates or mandates usage of the word quantum.

2. When speaking to my colleagues about physics, I use quantum (or variants of it) as an adjective, noun, and verb (at least).

-- Examples of adjective usage: quantum physics (physics associated with the very small, etc, based on the ideas of Planck, Einstein, Bohr, Heisenberg, etc), quantum field theory (the combination of quantum physics and classical field theory), quantum information theory (the combination of quantum physics and classical information theory)

-- Examples of noun usage: quantum of energy (a unit of energy), quantum of light (a photon), flux quantum (a particular amount of magnetic flux relevant to the physics of superconductors)

-- Examples of verb usage: to quantize a theory (a process of taking a classical theory and producing a quantum version of it i.e. to quantize the electromagnetic field is to pass from classical electrodynamics to quantum electrodynamics)

3. Wave mechanics is not inconsistent with quantization of energy. Since you indicated a desire to avoid mathematics, I shall try to be heuristic. For a particle in a box, the quantization of energy comes from the requirement that the wavelength of the particle fit into the box. So assigning a particle wave like characteristics does not automatically imply that everything is "continuous". This is actually a result familiar from the classical theory of the electromagnetic field i.e. the discrete possibilities for electromagnetic waves in a cavity.

Hope this helps.

PS Please let me know if I've been too heuristic for you.

 

[Born2bwire]

See my first post.

My understanding is that it is the Unit of Action of a Quantum of Energy. Maybe it could be called "oomph" ! It is applicable not only to photons but to ANY particle containing energy (all of them ?). It stands by itself as a unit.

It is the very basis of Quantum Mechanics and I am guessing if you (like I used to) think of it as E/f then your understanding of Quantum Physics is not as deep as it could be (I am willing to be shot down in flames on this statement !).

The fact that you have no idea of what action is rather disturbing in its own right. If you want to know what the action is you need to learn Lagrangian physics and then path integral theory and how it relates to quantum mechanics and quantum field theory.

 

[Vanadium 50]

I am not exactly a novice. Well-informed amateur would be a better way of putting it... I do have as my bible a book "Quantum Reality" by Nick Stevens which gives an eye-opening explanation of the quantum.

It's Nick Herbert, and reading a popular book does not make someone well-informed on a topic. Certainly not well enough to tell experts they are wrong.

The fact that you have no idea of what action is rather disturbing in its own right.

Born2bwire is right - there is something in mechanics called action, but it is more precisely defined than "oomph". It is not an energy, and if you took a look at the units, you would see that it doesn't even have the units of energy.

 

[trogan]

The fact that you have no idea of what action is rather disturbing in its own right. If you want to know what the action is you need to learn Lagrangian physics and then path integral theory and how it relates to quantum mechanics and quantum field theory.

If I am disturbed by something or someone I take it as an opportunity to learn something about myself. Why am I disturbing you ?

I did specify a definition for action in my opening post as "Mathematicians define action as an object’s momentum multiplied by the distance it travels; or the object’s energy multiplied by the time it is traveling–the two are equivalent.". The definition then went on to elaborate on this. This was not my definition but one I picked up from the internet.

It seems to me this is quite adeqate for a basic understanding what a quantum of energy is all about.

It also seems to me that the techniques you talk about contribute to a deeper understanding of action, especially in QF theory, yet it does not appear to be a complicated entity.

 

[trogan]

Hi trogan,

3. Wave mechanics is not inconsistent with quantization of energy. Since you indicated a desire to avoid mathematics, I shall try to be heuristic. For a particle in a box, the quantization of energy comes from the requirement that the wavelength of the particle fit into the box. So assigning a particle wave like characteristics does not automatically imply that everything is "continuous". This is actually a result familiar from the classical theory of the electromagnetic field i.e. the discrete possibilities for electromagnetic waves in a cavity.


PS Please let me know if I've been too heuristic for you.

Thanks for your heuristically fine replies. I am not sure what you maen by wave length of a particle but don't want to pursue that now.

 

[trogan]

It's Nick Herbert, and reading a popular book does not make someone well-informed on a topic. Certainly not well enough to tell experts they are wrong.

Born2bwire is right - there is something in mechanics called action, but it is more precisely defined than "oomph". It is not an energy, and if you took a look at the units, you would see that it doesn't even have the units of energy.

Nick Herbet, of course. Thanks for the correction.

Oomph is pretty evocative though, don't you think . You are confusing me. I was under the very strong impression that the Quantum Unit of Action (or Planck's Constant) is 6.62606896(33)×10−34 J·s and Joules is a unit of energy. Is this not the case and if so what then do you mean ?

 

[Born2bwire]

If I am disturbed by something or someone I take it as an opportunity to learn something about myself. Why am I disturbing you ?

I did specify a definition for action in my opening post as "Mathematicians define action as an object’s momentum multiplied by the distance it travels; or the object’s energy multiplied by the time it is traveling–the two are equivalent.". The definition then went on to elaborate on this. This was not my definition but one I picked up from the internet.

It seems to me this is quite adeqate for a basic understanding what a quantum of energy is all about.

It also seems to me that the techniques you talk about contribute to a deeper understanding of action, especially in QF theory, yet it does not appear to be a complicated entity.

The problem is that when I asked you what the action was, you could not give it to me. You stated that the electron and photon have the same "action potential" yet you can not give me what that potential is when I asked. You need to start learning more about these things before you start basing conclusions upon them.

More importantly, how would having the same action dictate that two situations are the same? Going from the definition you reference, energy times time, I could give you the "action" in this sense of a 1 ton car that travels 1 second at 100 km/hr and say that it is the same as the action of a mole of C_60 buckyball traveling at 54 ft/s for 1 hour. What is of interest is how the action relates to physics in general, through its use in Lagrangian physics. If you learned about Lagrangian mechanics then you would easily see the answer to your question.

As for Planck's constant, to me, it really doesn't mean anything of much consequence. It's just a constant, we can always set it to any arbitrary non-zero number depending on our desired system of units. For example, if we were to use natrural units, then c=\hbar=1. The ubiquitious nature of \hbar popping up everywhere makes it rather difficult to describe what it is since it is present in the basic principles of quantum mechanics, like Schroedinger's equation or Feynman's path integral formulation. However, it is of interest that classical mechanics can be recovered by taking the limit of \hbar to zero with the path integral formulation.