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Author Topic: Can you answer these questions on quantum mechanics?  (Read 7952 times)

Offline micron98

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Hi,

I have been studying a quantum mechanics and could not yet understand a few things

  • how photon transforms itself as energy and back again travelling at light speed
  • how building blocks of matter able to maintain its speed and state
  • how quantum particles disappear and appear

So with my limited knowledge, i think that when particles such as photon or electrons , etc
they gain energy and their energy frequency changes so we cannot sense them anymore which give illusion that it simply disappeared.

However when these particles return to normal energy state, their frequency changes back to our energy frequency we can sense.

Perhaps there could more more type of force than what we know today.
« Last Edit: 14/06/2014 16:19:09 by JP »


 

Offline alancalverd

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Re: Things that I cannot yet understand at quantum level
« Reply #1 on: 14/06/2014 07:10:29 »
Quantum mechanics is a description, not an explanation, of the world. Don't expect to "understand" it - it just happens as it does, and we describe it by quantum mathematics. Sometimes there seems to be a bit missing in the equation, so we go hunting for a new particle that makes the maths work, and that's as close as you can get to understanding: "the equations usually balance". 
 

Offline PmbPhy

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Re: Things that I cannot yet understand at quantum level
« Reply #2 on: 14/06/2014 10:35:17 »
Quote from: micron98
Hi,

I have been studying a quantum mechanics and could not yet understand a few things

  • how photon transforms itself as energy and back again travelling at light speed
  • how building blocks of matter able to maintain its speed and state
  • how quantum particles disappear and appear
Those things are not yet known today.
 

Offline micron98

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Re: Things that I cannot yet understand at quantum level
« Reply #3 on: 14/06/2014 11:25:26 »
Quote from: micron98
Hi,

I have been studying a quantum mechanics and could not yet understand a few things

  • how photon transforms itself as energy and back again travelling at light speed
  • how building blocks of matter able to maintain its speed and state
  • how quantum particles disappear and appear
Those things are not yet known today.

I cannot remember where but I did hear that from one of youtube video.
I guess not all information on the net can be trusted.
 

Offline micron98

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Re: Things that I cannot yet understand at quantum level
« Reply #4 on: 14/06/2014 11:29:33 »
Don't expect to "understand" it - it just happens as it does

Thanks for the suggestion. Though my mind keeps on trying to understand it. Perhaps time for a some beer and sleep.
 

Offline lightarrow

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Re: Can you answer these questions on quantum mechanics?
« Reply #5 on: 15/06/2014 14:21:28 »
  • how photon transforms itself as energy and back again travelling at light speed
Others seems to have undertstood what you ask, but I sincerely don't have the least idea.
Quote
  • how building blocks of matter able to maintain its speed and state
The same as up.
Quote
  • how quantum particles disappear and appear
Are you referring to virtual particles or what?
Quote
So with my limited knowledge, i think that when particles such as photon or electrons , etc
they gain energy and their energy frequency changes so we cannot sense them anymore which give illusion that it simply disappeared.

However when these particles return to normal energy state, their frequency changes back to our energy frequency we can sense.

Perhaps there could more more type of force than what we know today.
Understood nothing even here.

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Offline Bill S

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Re: Can you answer these questions on quantum mechanics?
« Reply #6 on: 16/06/2014 19:09:26 »
Undoubtedly, Alan and Pete provided adequate responses that covered the questions; however, it is interesting that lightarrow wanted to look more closely. 

As a non-scientist, I wonder if my attempt at interpreting the questions might help.  Here goes, anyway. Micron98 can say if I'm wide of the mark.

Quote
how photon transforms itself as energy and back again travelling at light speed

Could this relate to the recurring question of whether or not photons “experience” time?  If so, the answer would need to address the lack of an inertial frame for a photon.

Quote
how building blocks of matter able to maintain its speed and state

  Discussions about particles usually talk of them as being in motion.  Eg, a particle may be here now, but somewhere else some time later.  Do particles have to stop this moving to become building blocks of matter? 

Quote
how quantum particles disappear and appear

Lightarrow’s question about virtual particles is the obvious one, here; or were you thinking of photons being absorbed, becoming energy, then being re-emitted as photons?

Beyond this point we seem to be moving towards new theories.
 

Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #7 on: 17/06/2014 01:50:19 »
Quote from: Bill S
Undoubtedly, Alan and Pete provided adequate responses that covered the questions; however, it is interesting that lightarrow wanted to look more closely.
You've got to be kidding!? What was it about 

i) Others seems to have undertstood what you ask, but I sincerely don't have the least idea.

ii) The same as up.

iii) Are you referring to virtual particles or what?

iv) Understood nothing even here.

that gave you the impression that lightarrow wanted to look more closely? Please don't get me wrong. I respect lightarrow. I just don't see these responses as indicating that he wanted to look more closely.

Quote from: Bill S
Quote
how photon transforms itself as energy and back again travelling at light speed
Could this relate to the recurring question of whether or not photons “experience” time?  If so, the answer would need to address the lack of an inertial frame for a photon.
No. The question has to do with the mechanism and process of exactly how the photon is "transformed from energy to the photon and back again."

I didn't pay close enough attention to the way he phrased this question. He assumes that there is a "substance" called "energy" from which the photon is created. This is quite wrong and based on a widely held misconception of what energy really is. For the correct understanding of energy please see
http://home.comcast.net/~peter.m.brown/mech/what_is_energy.htm

Quote from: Bill S
Quote
how building blocks of matter able to maintain its speed and state
Discussions about particles usually talk of them as being in motion.  Eg, a particle may be here now, but somewhere else some time later.  Do particles have to stop this moving to become building blocks of matter? 
I believe that he's confused about how matter can stay in motion unless a force is applied. The answer is Newton's First Law of Motion, which says
http://scienceworld.wolfram.com/physics/NewtonsFirstLaw.html
Quote
Newton's first law states that body at rest remains at rest and a body in motion continues to move at a constant velocity unless acted upon by an external force.
Since this is a law of physics (aka a postulate) it can't be proved just like all the laws of nature. But if you think of it, it makes perfect sense. Suppose it wasn't true. Then how would a body change its state of motion? If it did then why did it change in the exact way that it did? It would represent a break of symmetry that constant motion represents and there's no reason to change in one particular way over the other. The only thing that makes sense is for it to just keep going.
 

Offline lightarrow

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Re: Can you answer these questions on quantum mechanics?
« Reply #8 on: 17/06/2014 21:21:00 »
Quote
Could this relate to the recurring question of whether or not photons “experience” time?  If so, the answer would need to address the lack of an inertial frame for a photon.
No. The question has to do with the mechanism and process of exactly how the photon is "transformed from energy to the photon and back again."
This is exactly an example of statement I don't understand because for me is meaningless.
Quote
I didn't pay close enough attention to the way he phrased this question. He assumes that there is a "substance" called "energy" from which the photon is created.
If you understood this about him, my compliments to your divination abilities. Do you think this because you have already found other people meaning the same? It's the first time I hear it.

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Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #9 on: 18/06/2014 03:38:40 »
Quote from: lightarrow
If you understood this about him, my compliments to your divination abilities. Do you think this because you have already found other people meaning the same? It's the first time I hear it.
“divination” my butt. Why do you have to be so rude/sarcastic? I don’t like sarcasm. It’s the lowest form of humor.

It’s what’s known as a deduction. Perhaps you’ve heard of it? I deduced that he thinks that light is transformed from some sort of substance called “energy”. Any time anybody ever says something like “transformed from energy” that’s what they mean. Recall the opening question where he says
Quote
how photon transforms itself as energy and back traveling at light speed.


micron98 - Is that what you meant? If not then what did you mean when you wrote photon transforms itself as energy?
 

Offline Bill S

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Re: Can you answer these questions on quantum mechanics?
« Reply #10 on: 18/06/2014 14:39:21 »
Quote from: Pete
I just don't see these responses as indicating that he wanted to look more closely.

Quote
I didn't pay close enough attention to the way he phrased this question.

I rest my case.

I really appreciate the time and effort that experts devote to trying to help us non-experts towards a better understanding of science.  One very important thing, though, is understanding the possible naïvety of hitch-hikers’ questions.  Whilst I am quite prepared to try everyone’s patience by persisting, others may be put off further enquiry by dismissive or seemingly aggressive responses. 

I am well aware that experts’ time is precious, but please recognise that there are question that we non-experts ask that may seem to make no sense to you.  However, they are the question we need to have answered, and the process of making sense of them is in itself a learning experience.
 

Offline JP

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Re: Can you answer these questions on quantum mechanics?
« Reply #11 on: 18/06/2014 16:54:14 »
So if a poster doesn't clarify the meaning of an initial post, does that mean the question is in a superposition of meaning states?
 

Offline Bill S

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Re: Can you answer these questions on quantum mechanics?
« Reply #12 on: 18/06/2014 18:04:02 »
That depends on how you define "meaning states". 
 

Offline Bill S

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Re: Can you answer these questions on quantum mechanics?
« Reply #13 on: 18/06/2014 18:28:01 »
Assuming JP is right, let’s try to decohere each question.  Hope you’re still with us, micron98, we’ll need you to correct any misinterpretation.

Quote
how photon transforms itself as energy and back again travelling at light speed

1.  If a photon is absorbed by an atom and causes an electron to jump to a higher energy state, could this be considered as the photon being transformed into energy?

2.  When the electron returns to its ground state, it loses energy and emits a photon.  Can this be considered as energy being transformed into a photon? 

3.  Given that there is not a "substance" called "energy", but that there is a process by which a
Quote
photon is "transformed from energy to the photon and back again."

what is involved in this process?

4.  Micron mentioned “travelling at light speed”, which caused me to wonder if he was thinking of the idea (still championed in some circles) that photons might not “experience” time.
 

Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #14 on: 18/06/2014 18:45:48 »
Quote from: Bill S
I rest my case.
Hi Bill,

I don't understand. What was your "case"? If I made a mistake in my assumption then I appologize. I do my absolute best in trying to determine what people are looking for from their posts but I'm far from perfect. You have to help us along the way. I'm sure you know that about posting in a physics discussion forum, right?

Quote from: Bill S
One very important thing, though, is understanding the possible naïvety of hitch-hikers’ questions.
Who are these "hitch-hikers"? Do you mean the people who post here?

Quote from: Bill S
I am well aware that experts’ time is precious, but please recognise that there are question that we non-experts ask that may seem to make no sense to you.
We're very aware of that, Bill. I myself have been doing this for many many years.
 

Offline Bill S

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Re: Can you answer these questions on quantum mechanics?
« Reply #15 on: 18/06/2014 20:42:35 »
Quote from: Pete
Who are these "hitch-hikers"? Do you mean the people who post here?


I have been using the term “hitch-hikers on this and other forums for some time.  Occasionally  I have offered a brief definition, but if something fuller is required, it would refer to people who have no particular expertise or training in science, and are not professionally involved in scientific pursuits.  These people have a keen interest, either in science generally, or in some aspect in particular.  They will feed their interest by seeking out and reading books of popular science and articles in magazines.  These days, they will search on line and, perhaps, find others there from whom they may learn, and with whom to share ideas.
 

Offline Bill S

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Re: Can you answer these questions on quantum mechanics?
« Reply #16 on: 18/06/2014 20:54:22 »
Quote from: Pete
I don't understand. What was your "case"?

No big deal there Pete; certainly nothing to apologise for. 

You have undoubtedly noticed that a pet theme of mine is that experts and non-experts tend to think along different lines, so that what one says is not necessarily what the other hears.  There is no blame or fault attached to this, it just needs some persistence and patience to overcome it.
 

Offline lightarrow

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Re: Can you answer these questions on quantum mechanics?
« Reply #17 on: 18/06/2014 21:40:55 »
Quote from: lightarrow
If you understood this about him, my compliments to your divination abilities. Do you think this because you have already found other people meaning the same? It's the first time I hear it.
“divination” my butt.
;DYou are very funny (hope you don't feel hurt by this statement).
Quote
Why do you have to be so rude/sarcastic? I don’t like sarcasm. It’s the lowest form of humor.
Pete, I am not able to make sarcasm in italian (my language), you can imagine if I could do it in english  :)
(unless I'm more intelligent than what I thought, but it's difficult for me to believe it).
Quote
It’s what’s known as a deduction. Perhaps you’ve heard of it? I deduced that he thinks that light is transformed from some sort of substance called “energy”. Any time anybody ever says something like “transformed from energy” that’s what they mean.
I sincerely have never heard such a statement in english language.
I was sincere when I wrote about "divination ability", no sarcasm at all. And I'm completelly sincere when I write that I don't know what the OP intended to ask.
Furthermore, it's not possible to compare a physical concept as "a photon" with "a property" of physical sysyems, as "the energy", It's like asking "why do apples transform into the green colour?"
One thing is the physical object "apple" and another thing is *the property* "green colour" of an apple.

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Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #18 on: 19/06/2014 06:50:14 »
Quote from: lightarrow
Pete, I am not able to make sarcasm in italian (my language), you can imagine if I could do it in english  :)
Then I apologize for misinterpreting what you said.

Quote from: lightarrow
I sincerely have never heard such a statement in english language.
That’s strange. Are you saying that the term deduced can’t be translated into Italian? I find that hard to believe. A friend of mine speaks Italian. I’ll ask him for the translation.

Quote from: lightarrow
I was sincere when I wrote about "divination ability", no sarcasm at all.
Okay. I understand now. Thank you for clearing that up. What you just told me about you being Italian helps clear up a lot of the things you’ve said in the past. Nothing specific mind you but I think that there’s a slight language barrier that has gotten in our way. Now that I’m aware of it I can adjust my writing style a bit and hopefully it will compensate.

It's now clear to me that I've misjudged you all these years. For that I humbly appologize. :)



Quote from: lightarrow
And I'm completelly sincere when I write that I don't know what the OP intended to ask.
Then let’s ask him. :)

A good article on this subject is Teaching E = mc^2 by Ralph F Baierlein, The Physics Teacher, March 1991, pages 170-175. I can upload it onto my website long enough for anybody who wants to read it.
 

Offline lightarrow

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Re: Can you answer these questions on quantum mechanics?
« Reply #19 on: 19/06/2014 12:04:36 »
Quote from: lightarrow
I sincerely have never heard such a statement in english language.
That’s strange. Are you saying that the term deduced can’t be translated into Italian? I find that hard to believe. A friend of mine speaks Italian. I’ll ask him for the translation.
:)I'm not referring to "deduce", I'm referring to:
<<The question has to do with the mechanism and process of exactly how the photon is "transformed from energy to the photon and back again.">>
Quote
Quote from: lightarrow
I was sincere when I wrote about "divination ability", no sarcasm at all.
Okay. I understand now. Thank you for clearing that up. What you just told me about you being Italian helps clear up a lot of the things you’ve said in the past. Nothing specific mind you but I think that there’s a slight language barrier that has gotten in our way. Now that I’m aware of it I can adjust my writing style a bit and hopefully it will compensate.
Ok, thank you, I thought you already knew I am not native english, forgive me not to have specified it to you.
Quote
It's now clear to me that I've misjudged you all these years. For that I humbly appologize. :)
Quote from: lightarrow
And I'm completelly sincere when I write that I don't know what the OP intended to ask.
Then let’s ask him. :)
A good article on this subject is Teaching E = mc^2 by Ralph F Baierlein, The Physics Teacher, March 1991, pages 170-175. I can upload it onto my website long enough for anybody who wants to read it.
Ok, I'll be happy to read it.
Regards.

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Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #20 on: 19/06/2014 21:55:51 »
Quote from: lightarrow
I'm referring to:
<<The question has to do with the mechanism and process of exactly how the photon is "transformed from energy to the photon and back again.">>
The person who asked that doesn't understand energy and as such doesn't know that this question has no meaning. I'm sure you understand as much.

Quote from: lightarrow
Ok, I'll be happy to read it.
Anybody who wants to understand that question should read it. However I can't find it. However I did find a similar article by the same author.

Does nature convert mass into energy? by Ralph Baierlein, Am. J. Phys., 75 (4), April 2007
Quote
Abstract - First I provide some history of how the equation E=mc2 arose, establish what “mass” means in the context of this relation, and present some aspects of how the relation can be understood. Then
I address the question, Does E=mc2 mean that one can “convert mass into energy” and vice versa?
I've uploaded it onto my website at
http://home.comcast.net/~peter.m.brown/ref/baierlein.pdf

I spoke to the author. We're on the same wavelength when it comes to this subject. :)
 

Offline allan marsh

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Re: Can you answer these questions on quantum mechanics?
« Reply #21 on: 19/06/2014 22:37:05 »
Quantum mechanics with superposition, entanglement and the change in state when observed automatically infers that reality is in question... As we know it. Equally time and gravity has great questions
Read Richard Feynman,s view
 

Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #22 on: 19/06/2014 23:57:13 »
Quote from: allan marsh
Quantum mechanics with superposition, entanglement and the change in state when observed automatically infers that reality is in question...
I can't imagine why. In fact I can't even see what it'd mean for reality to be in question unless one is halucinating.

Quote from: allan marsh
Read Richard Feynman's views.
What are you refering to? To suggest such a thing it's necessary to say where the view that you're referring to is recorded.
 

Offline allan marsh

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Re: Can you answer these questions on quantum mechanics?
« Reply #23 on: 20/06/2014 09:00:33 »
Richard Feynman direct filmed quote

"Anyone who claims to understand quantum theory is either lying or crazy"!!!!!!

Nobel prize winner

See actual on YouTube

Now which are you or neither ?

 

Offline PmbPhy

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Re: Can you answer these questions on quantum mechanics?
« Reply #24 on: 20/06/2014 09:34:10 »
Quote from: allan marsh
Richard Feynman direct filmed quote

"Anyone who claims to understand quantum theory is either lying or crazy"!!!!!!
That doesn't mean that reality is in question. It means that since we live in a macroscopic world and not a quantum world we never directly experience what a true quantum reality is like. We'll never experience it because we're macroscopic beings. For that reason we'll never fathom it. I.e. quantum mechanics is not in question in that sense. We're just incapable of comprehending the nature of the quantum world.

That's what Feynman meant. He didn't mean that we don't know whether or not quantum mechanics is accurate or not.

Quote from: allan marsh
Nobel prize winner
Yes. I know that quite well, thank you.

Quote from: allan marsh
Now which are you or neither ?
If you truly understood what Feynman meant by what he said you wouldn't ask such a rude question.
 

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Re: Can you answer these questions on quantum mechanics?
« Reply #24 on: 20/06/2014 09:34:10 »

 

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