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Messages - SueDoeNimm

1
I can imagine inventing and building a time machine and using it to travel back in time.  (Many people have imagined just such a thing.)

Is that logically possible?

If you answer 'no' your argument fails.  If you answer 'yes' I have a followup question.

I think it is logically possible, in a sense that it's not contradictory, just as I can imagine conjuring up fire from my palm or God creating the Universe from nothing. The 'how' is not important in the matter, if that's your follow-up question.

Sounds like a 'yes' (if not somewhat hedged).

I can imagine inventing and building a time machine and using it to travel back in time and then smashing the machine just before I could use it.

Is that logically possible?

2
Choose Your Own Topic / Re: William Lane Craig and Divine Genocides
« on: August 25, 2013, 01:46:47 am »
Lol, talking about how god flooded the entire Earth, since god was omnipotent, and designed humans, he already knew humans were going to be bad, so why make the humans, then kill them if he already knew the outcome and he knew he wouldn't like it? Obviously a contradiction between the facts and omnipotent/all loving god. Also, why did god allow the Canaanites to exist, to then sacrifice children, if they were just going to end up doing this anyway? It seems like there's something wrong with the designer, not the designed. Clearly, since we mess up so much, obviously we are not the product of anything divine. A perfect designer always makes a perfect design, unless the designer is incompetent, and if the designer is incompetent, that just means there is no intelligent designer.

The evidence continues to mount towards atheism.

God didn't know people were going to sin before He created them?  I must have missed that one in Sunday school as a kid. It always seemed obvious to me that the flood was an instance of divine judgment, a way to wake up the world of how desperate their situation is.

The central thesis of Christianity is that the world is messed up (due to the Fall) and that God will redeem it. Saying God doesn't exist because the world has unpleasantness in it is akin to saying automobiles don't have designers because drunks occasionally crash them. For that reason, only sophomoric gnus argue the logical problem of evil anymore.

If automobile designers were omnipotent, omniscient, and benevolent they would design automobiles such that they could never crash.


3
I wish to discuss this argument as I think it's a very strong one. Any objections from naturalists?

http://www.youtube.com/watch?v=WOTn_wRwDE0

Here's a nicely formulated version of it:

"1. What is imaginable is logically possible.


I can imagine inventing and building a time machine and using it to travel back in time.  (Many people have imagined just such a thing.)

Is that logically possible?

If you answer 'no' your argument fails.  If you answer 'yes' I have a followup question.


4
Choose Your Own Topic / Re: Is there really an all loving God?
« on: June 10, 2013, 11:49:19 pm »
It just doesn't make sense to me anymore that an all loving God would or could permit so much suffering in the world.

It's quite easy to just say that there is some unknown greater good involved.

I tend to think we are just lying to ourselves to think an all loving God would permit such horrible suffering of his children.

I think that either he can't interfere or he simply isn't the all loving God we are taught he is.


I do believe in God, but there is something very wrong going on in this world, there is no reason to permit so much suffering, we are not being told the truth.

It just doesn't make sense that he can be so powerful and permit the horrors people face every day of their lives.

Right.  It doesn't make sense.

5
Choose Your Own Topic / Re: Why Fine-Tuning is Irrelevant
« on: February 11, 2013, 10:32:35 pm »

Not at all. I have made no claim that a designer makes it more likely that a universe with intelligent life will be finely tuned.

I claim that a fine tuned universe makes it more likely that a designer exists.

You like, Weisberg, seem to be fundamentally confused about the difference in these two conclusions. I pointed this out earlier.

A = fine tuned universe
B = God
C = non-fined tuned universe
D= not-God


Here is the proposition of the Fine Tuning Argument:

1) If A then probability of B is greater than D


Do you say the universe IS fine tuned or do you just say the universe APPEARS fine tuned?   (If you say it IS fine tuned then it seems you are assuming your conclusion.)

Is there a possible natural explanation for an appearance of fine tuning?

Is the universe fine tuned for the existence of souls?

Is it possible that God could have created the universe such that life was not naturally possible yet he made it exist by supernatural intervention?

Quote

Here is the proposition that Weisberg and you are assuming:

2) If B then the probability of A equals C

Proposition #1 is different than proposition #2 and #2 is irrelevant to whether or not #1 is a valid argument.

Maybe not immediately.

6
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 16, 2013, 12:37:45 am »

{snip}

2- In the case of the quantum mechanics electron the Probability function is a wave.

     take a look at the link image:

http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/images/psi/onewave.gif


I'll just point out here that that particular wave function is non-physical and can't happen.  The second derivative at x = 0 and x = 2*Pi  is infinite implying infinite momentum.

IMHO, looking at that image, my impression is that the wave would be described by

F(x) = Sin x  ; 0 =< x =< 2Pi
F(x) = 0 ;   x < 0 , x > 2Pi.


But:

    F(x) = 0 ;   x <= 0 , x > 2Pi.

is also consistent.  So you have two different values for the derivative at x = 0.

The function has no derivative.
http://en.wikipedia.org/wiki/Derivative#Continuity_and_differentiability
It is non-physical and can't be an actual wave function.

Are we looking at the same  figure ?

do you see any discontinuity in the original figure ??

You don't?

Do you see the discontinuity in the wikipedia article?

Do you agree that
  y = |x|
is discontinuous?



My error.  It is not discontinuous.  But it is not differentiable.

The following is still applies to continuous, non differentiable functions.

Quote
Quote

Is there a difference (derivative-wise) between:

  y = |x|

and

   y = -x      x < 0
   y = x       x >= 0

and

   y = -x     x <= 0
   y = x      x >= 0

?


I did not say the Wikipedia, does not show cases of discontinuity, and that is not the issue at hand.
I am sorry, this case you show has got nothing to do with the relevant case in the original figure of the wave function. An straw man if you will. :)

This is the graph of the wave function in question:
http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/images/psi/onewave.gif

And it is not discontinuous, as far as I can see.


Correct.  But it is not differentiable.  It cannot be a real world wave function.  It could be a solution to an "infinite square well" situation as described in:
http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/papers/psi.html
But an infinite square well cannot exist in the real world.

If one had a finite square well there could be a similar solution but the wave would smoothly approach 0 at the ends.

Agree, You are right.

It is still a solution used to many ends. It is a simple case, that is helpful in understanding some of the features of quantum mechanics, and it also provides support to finding approximate solutions to real physical situations related to particles inside a well of potential.

Yes.  We agree.

7
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 16, 2013, 12:07:50 am »

(Specifically I asked about the truth of "The electron was on the left side before measurement".  But that detail might not matter.)


And I answer the statement is false. It is false for either side ( it is not on the right nor the left).

Quote from: Sue
Was it on both the left and right side before 'collapse'? 

None, there is no electron, there is a distribution wave. A potential.


Interesting.
So it is apparently your view that this 'potential' is a distinctly different thing from the electron.  The potential changes into an electron at the instant of observation of its location.  But how can that be?  How can a hydrogen atom be a hydrogen atom without an electron?  Until we observe where the electron is the hydrogen atom has no electron (according to you).  There is just a potential but no electron.  So how is a hydrogen atom electrically neutral?

Does the potential have electrical charge?  Does it have mass?

(Hmm.  When, if ever, does an electron turn back into a potential?) 

Quote

Quote from: Sue
Does it have width and then collapse into a point?  (Previously you spent a lot of time insisting that an electron was a point particle that always has a specific unique location, did you not?)

I did not say THE ELECTRON WAS A POINT PARTICLE, I said it is TREATED MATHEMATICALLY as a point particle.


And that seems rather equivocal.  Is how-it-treated the same as what-it-is?  I asked you for clarification previously.  I don't recall that you gave a direct answer.

When the potential 'collapses' into an electron how wide is the electron?

Quote

 I gave you references for the electron being located. If the scientists that wrote them , know less about the subject than you,  it has got nothing to do with me, I am not a scientist, thus I post the references.


Argument from authority and ad hom.

Quote

You are asking were is the baby just before conception.


I don't see that that is analogous.  Elaborate if you will.

Quote
Another reference

"
the particle — is described by a wave, which encodes the information  about what an observer is likely to find the particle doing when he observes it. When an observation is made the wave ‘collapses' into a particular state that ascribes a definite sharp value to whatever has been observed.

Davies, Paul (2006-09-28). God and the New Physics (Penguin Science) (Kindle Locations 2234-2236). Penguin UK. Kindle Edition.
"

"The particle [] is described by a wave."  But it is not really a wave?

How sharp is 'sharp'?  A point?  (You have said, No.)

Quote

Quote from: Sue
'Logic' might be a respectable and developed discipline.  That doesn't mean that classical logic is absolute or has universal domain.

Well , I never said that it was absolute, I only rejected your assertion that it was folky.


It has appeared to me that you strongly implied that 'logic' is absolute.

Yes, my 'folky' comment was dismissive.  I also acknowledge that I had not fully recognized the academic value of various types of logic.  But you must also remember that I, early on, revised my comment from 'folky' to "limited in domain".

Quote

Quote from: Sue
If classical logic claims to be absolute and universal in domain then QM has a negative impact.

No such a claim has been advanced by logicians. ....

Then they should [not] object if some of the axioms of classical logic are found not to hold in nature.

8
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 14, 2013, 10:57:28 pm »

{snippage}


:) The information has been submitted, I don´t care if you think I am quote mining, I do mind if you call me dishonest, I have invested much of the little time I have investigating on this, I have quoted, but also provided the links, for all to make their minds alone.


And I would welcome others to chime in.

Quote

You asked what is the truth state of the electron right of left before measuring and I said it is false that it is at the left or the right, since it is not collapsed, I did not have to use no other than classical logic for that.


Could you show your work?  I don't see how that follows.

(Specifically I asked about the truth of "The electron was on the left side before measurement".  But that detail might not matter.)

Was it on both the left and right side before 'collapse'?   Does it have width and then collapse into a point?  (Previously you spent a lot of time insisting that an electron was a point particle that always has a specific unique location, did you not?)

Quote

When we started this posts, you were being dismissive about logic, and I have shown that such attitudes and statements coming from it, are unwarranted.

I said from the beginning I am an amateur and I can be wrong,


Then heed my criticism about mixing classical and quantum physics.

Quote

thus the heavy quoting, I also said from the beginning not even scientists are all that clear about these subjects, my only contention is that what ever the state of QM is at this moment, it does not have a negative impact on logic, as logic is a quite respectable and developed discipline.


'Logic' might be a respectable and developed discipline.  That doesn't mean that classical logic is absolute or has universal domain.

QM doesn't negatively impact the "infield fly rule" in the respectable and developed discipline of baseball logic.  But baseball doesn't claim to be absolute or have universal domain.

If classical logic claims to be absolute and universal in domain then QM has a negative impact.

9
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 14, 2013, 09:01:43 pm »

{snip}

2- In the case of the quantum mechanics electron the Probability function is a wave.

     take a look at the link image:

http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/images/psi/onewave.gif


I'll just point out here that that particular wave function is non-physical and can't happen.  The second derivative at x = 0 and x = 2*Pi  is infinite implying infinite momentum.

IMHO, looking at that image, my impression is that the wave would be described by

F(x) = Sin x  ; 0 =< x =< 2Pi
F(x) = 0 ;   x < 0 , x > 2Pi.


But:

    F(x) = 0 ;   x <= 0 , x > 2Pi.

is also consistent.  So you have two different values for the derivative at x = 0.

The function has no derivative.
http://en.wikipedia.org/wiki/Derivative#Continuity_and_differentiability
It is non-physical and can't be an actual wave function.

Are we looking at the same  figure ?

do you see any discontinuity in the original figure ??

You don't?

Do you see the discontinuity in the wikipedia article?

Do you agree that
  y = |x|
is discontinuous?



My error.  It is not discontinuous.  But it is not differentiable.

The following is still applies to continuous, non differentiable functions.

Quote
Quote

Is there a difference (derivative-wise) between:

  y = |x|

and

   y = -x      x < 0
   y = x       x >= 0

and

   y = -x     x <= 0
   y = x      x >= 0

?


I did not say the Wikipedia, does not show cases of discontinuity, and that is not the issue at hand.
I am sorry, this case you show has got nothing to do with the relevant case in the original figure of the wave function. An straw man if you will. :)

This is the graph of the wave function in question:
http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/images/psi/onewave.gif

And it is not discontinuous, as far as I can see.


Correct.  But it is not differentiable.  It cannot be a real world wave function.  It could be a solution to an "infinite square well" situation as described in:
http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/papers/psi.html
But an infinite square well cannot exist in the real world.

If one had a finite square well there could be a similar solution but the wave would smoothly approach 0 at the ends.


10
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 13, 2013, 10:52:52 pm »

{snip}

2- In the case of the quantum mechanics electron the Probability function is a wave.

     take a look at the link image:

http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/images/psi/onewave.gif


I'll just point out here that that particular wave function is non-physical and can't happen.  The second derivative at x = 0 and x = 2*Pi  is infinite implying infinite momentum.

IMHO, looking at that image, my impression is that the wave would be described by

F(x) = Sin x  ; 0 =< x =< 2Pi
F(x) = 0 ;   x < 0 , x > 2Pi.


But:

    F(x) = 0 ;   x <= 0 , x > 2Pi.

is also consistent.  So you have two different values for the derivative at x = 0.

The function has no derivative.
http://en.wikipedia.org/wiki/Derivative#Continuity_and_differentiability
It is non-physical and can't be an actual wave function.

Are we looking at the same  figure ?

do you see any discontinuity in the original figure ??

You don't?

Do you see the discontinuity in the wikipedia article?

Do you agree that
  y = |x|
is discontinuous?


Is there a difference (derivative-wise) between:

  y = |x|

and

   y = -x      x < 0
   y = x       x >= 0

and

   y = -x     x <= 0
   y = x      x >= 0

?

11
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 13, 2013, 10:30:27 pm »
Quote from: me
Again confusing things. There is the PoEM and there is the principle of Bivalence.
You are right in saying, I am assuming Bivalent logic, because you expressed nonconformity with the PoEM, not with the principle of bi-valence.


Quote from: Sue
Dishonest.  A dodge.  A red herring.
The PoEM and bivalence are inextricable.  The PoEM is basically an assertion of bivalence.
Your 'assumption' of Bivalent logic (as a distinct thing) _because_ I spoke to PoEM is an admission of your dodge.[/colo]



Indeed, I was in error here.  (But this is no peace offering.  I still accuse Ontalogicalme of quote mining, quoting out of context, confusing classical and quantum physics, and dodging questions.)

Quote




QM can be analysed just fine with classical logic.And I have shown that. " I have refuted all your points, with references and information.


False.  Classical logic fails at the quantum level.  The HUP describes inescapable uncertainty.  There are properties of mater that at times are objectively unknowable.  Reality is not bivalent.  A proposition may be unknown and not true and not false.  Classical logic fails.

Ontalogicalme's (your, if you are still listening) 'refutation' is not refutation.  He (you) has quote-mined, quoted articles he didn't understand, equivocated on classical vs quantum physics, and [not] responded to follow up questions.

Quote


Quote from: me

So your proposition that the principle of the excluded middle is false, and the proposition that the principle of the excluded middle is right , can be both right and both false, which is of course an absurd.



Quote from: Sue
Yes, the circular, question begging, straw man you have presented is absurd.

What straw man? this is gone too far.


Not just a straw man.  A circular, question begging, straw man.

Quote

Again you are mixing the principle of bivalence with the PoEM. If I did not assume bivalence, I would have been building an strawman, by assuming something you did not say.Or, shoud I assume you reject all logic?


Classical logic is bivalent.  I do not assume bivalence is true.  By assuming bivalence you made a straw man.

Quote

And yes , there is three value logic, paraconsistent logic, fuzzy logic, and others where the PoEM does not hold, and even the principle of bivalence does not hold, they are not , necessarily, the same type of logic, though, in some, both do not hold, in others one of them hold and the other does not.

Quote from: Sue

You've basically conceded my point here.  You have admitted other systems of logic contrary to the PoEM and not said or shown that the PoEM is 'necessary' or has any privileged position.


I haven´t conceded anything, ...


He has (you have) admitted other systems of logic contrary to the PoEM and not said or shown that the PoEM is 'necessary' or has any privileged position.... especially with regard to QM.

12
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 10, 2013, 11:37:22 pm »

I have to add
I merely meant to throw in a light hearted comment about Aristotles physics. You mentioned concepts like "nature abhors a vacuum", and so on, all those that you mentioned, do not come from logic, they are 2300 years old physics, if you think that you can crucify Aristotle for that, don´t mind me.


Quote from: Sue

It seems rather equivocal and disingenuous to try to divorce logic from the observation of nature.

 


You are entitled to your opinions. I am done with this subject.

Quote from: me

Now when it comes to non vague assertions or propositions, the principle of the excluded middle says that of any two contradictory propositions, one must be true and the other one false.




Quote from: Sue

By only allowing 'true' and 'false' truth values and excluding 'unknown' the PoEM is limited in scope.  It is not coherent with nature at the quantum level.  In nature the the proposition "the electron was on the left side of the atom just before being measured" has no truth value.


If you are using the Copenhagen Interpretation ( you are? correct? ) you can say that the particle was not collapsed, so, it is false, it was not at the left side of the atom before being measured, since it was not collapsed.


I've been trying to figure out what the Ontologicalme Interpretation is.  What is the Ontologicalme Interpretation (OI)?  Where was the particle prior to measurement under the OI.

Quote

Quote from: me
so for example if you say that the principle of the excluded middle is false, then it means that the proposition the  two contradictory propositions can be both true or both false.



Quote from: Sue


No, it doesn't.  You are being circular and begging the question.  You are assuming bivalent logic and the truth of the PoEM in analyzing the truth of the PoEM.

Again confusing things. There is the PoEM and there is the principle of Bivalence.
You are right in saying, I am assuming Bivalent logic, because you expressed nonconformity with the PoEM, not with the principle of bi-valence.


Dishonest.  A dodge.  A red herring.
The PoEM and bivalence are inextricable.  The PoEM is basically an assertion of bivalence.
Your 'assumption' of Bivalent logic (as a distinct thing) _because_ I spoke to PoEM is an admission of your dodge.

Quote

Quote from: me

So your proposition that the principle of the excluded middle is false, and the proposition that the principle of the excluded middle is right , can be both right and both false, which is of course an absurd.




Quote from: Sue
Yes, the circular, question begging, straw man you have presented is absurd.

What straw man? this is gone too far.

Again you are mixing the principle of bivalence with the PoEM. If I did not assume bivalence, I would have been building an strawman, by assuming something you did not say.Or, shoud I assume you reject all logic?

And yes , there is three value logic, paraconsistent logic, fuzzy logic, and others where the PoEM does not hold, and even the principle of bivalence does not hold, they are not , necessarily, the same type of logic, though, in some, both do not hold, in others one of them hold and the other does not.


You've basically conceded my point here.  You have admitted other systems of logic contrary to the PoEM and not said or shown that the PoEM is 'necessary' or has any privileged position.

Quote

So I conclude my postings on this

I'll bet not.

13
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 09, 2013, 11:02:22 pm »

{snip}

2- In the case of the quantum mechanics electron the Probability function is a wave.

     take a look at the link image:

http://www4.ncsu.edu/unity/lockers/users/f/felder/public/kenny/images/psi/onewave.gif


I'll just point out here that that particular wave function is non-physical and can't happen.  The second derivative at x = 0 and x = 2*Pi  is infinite implying infinite momentum.

IMHO, looking at that image, my impression is that the wave would be described by

F(x) = Sin x  ; 0 =< x =< 2Pi
F(x) = 0 ;   x < 0 , x > 2Pi.


But:

    F(x) = 0 ;   x <= 0 , x > 2Pi.

is also consistent.  So you have two different values for the derivative at x = 0.

The function has no derivative.
http://en.wikipedia.org/wiki/Derivative#Continuity_and_differentiability
It is non-physical and can't be an actual wave function.


14
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 09, 2013, 10:42:12 pm »

Addressing the latter part:


I have to add
I merely meant to throw in a light hearted comment about Aristotles physics. You mentioned concepts like "nature abhors a vacuum", and so on, all those that you mentioned, do not come from logic, they are 2300 years old physics, if you think that you can crucify Aristotle for that, don´t mind me.


It seems rather equivocal and disingenuous to try to divorce logic from the observation of nature.

 
Quote

But again, Aristotle logic ( his syllogisms are just fine).

You can check logic, in fact it has been checked quite a lot this last 100 years. That is the reason, there are many many types of logic, aside from syllogism and classical logic,  today, there is fuzzy logic for example and many others.

Now when it comes to non vague assertions or propositions, the principle of the excluded middle says that of any two contradictory propositions, one must be true and the other one false.


By only allowing 'true' and 'false' truth values and excluding 'unknown' the PoEM is limited in scope.  It is not coherent with nature at the quantum level.  In nature the the proposition "the electron was on the left side of the atom just before being measured" has no truth value.

Quote

so for example if you say that the principle of the excluded middle is false, then it means that the proposition the  two contradictory propositions can be both true or both false.


No, it doesn't.  You are being circular and begging the question.  You are assuming bivalent logic and the truth of the PoEM in analyzing the truth of the PoEM.

Quote

So your proposition that the principle of the excluded middle is false, and the proposition that the principle of the excluded middle is right , can be both right and both false, which is of course an absurd.


Yes, the circular, question begging, straw man you have presented is absurd.


15
Choose Your Own Topic / Re: QM: My rejection of Schrodinger's cat
« on: January 08, 2013, 11:17:11 pm »




There are no particles in QM.  The very term 'quantum' stems from the original recognition of that fact.  (Sure, physicist still use the term 'particles' but at those times they are being informal or colloquial.  No physicist would say that a photon IS exactly a particle or IS exactly a wave.)

Quote from: me
Why...    {snip because the software is complaining about post length}


Quote from: Sue
Are you saying a photon is exactly a wave and just sometimes gives some of the appearance of a particle?

Are you saying an electron is exactly a particle and just sometimes gives some of the appearance of a wave?

Sue, I am sorry, but you seem to misconstrue all my answers. You said that the very term quantum came from the recognition of  the fact that There are no particles in QM.


How was I supposed to construe your words?  I found your statements to be not perfectly clear.  I asked a couple questions in order to get clarification.  I don't see that you have answered the questions.  If the answers are in your response please point them out to me.

In QM there are no classical Newtonian particles.  In classical physics an elemetary particle was viewed as a little ball with a (probably) fixed radius, with all the 'stuff' making up the 'particle' being within that radius, and the center being at a unique determinable position at all times.  There is no such thing in QM.

Sure, QMers will refer to an electron particle but that is informal and they know that an electron is not a little ball at one location.

Quote

And I proceeded to explain that, actually  the term quantum, came from the exact opposite fact of recognizing that an electromagnetic wave ( as light ), can be treated as energy packets (quantas), called in the case of light, photons.


'Opposite'?  That actually seems consistent with my point.  For centuries it was debated whether light was a wave or particle.  Einstein used the term 'quanta' rather than 'particle' (as in classical physics) because it is not a 'particle' (and not a classical wave).

And as before, I find your wording ambiguous.  What do you mean "can be treated"?  Does that mean the actually ARE energy packets?  Are they electromagnetic waves?  Are they both but neither?  Or are they just 'quanta'?

Quote

And complimented the information, adding that only later came the realization, that particles behavior could be modeled as waves ( DeBroglie)


What do you mean 'modeled'?  Is that a math trick?  Is the waveness a real part of the particle?  Is the particle part of the wave?

Quote

{snip}

Quote from: Sue

'Particle' like most words has many different senses:
http://dictionary.reference.com/browse/particle
And physicists often use it in the informal sense as you do.  It is convenient.  It is traditional.  And depending on the scale you are working at it is sufficiently accurate.  You can consider the Earth a particle if you are modeling the galaxy.


Sue, with all due respect, I cited references from Wikipedia, referring to the concept of particle from a physics point of view, you are citing a dictionary.


The dictionary citation was to give a clear illustration of senses and context in semantics.  It in no way was intended to limit or exclude other sources.

Quote
Quote from: Sue
No one has ever made a measurement that has shown a 'particle' (granting that term in the informal sense) to be a point at one exact (zero width) location.  The uncertainty principle is the expression of that fact of nature.  If you think my statement is not true please cite a case in which a particle has been shown to be a point at an exact location.

No one is saying that anything is a point. That would be absurd. not even Strings are supposed to be a point. What I said, is that the discrete values of a fundamental particles are taken to be localized at the position of the particle, and I quoted a reference where it says very clearly that , the mathematical treatment of fundamental particles is a point particle ( even when you said I was wrong), with the caveat in QM that , even being considered a point particle ( mathematically ) it is considered to occupy a  volume , due to  Heisenberg´s  uncertainty principle(HUP). The reference said, that the view of the fundamental particle was treated as a point particle, but that the model was complicated by the HUP.


Maybe there is some progress here because it had seemed to me you had been say a particle IS a point without spacial extent.  But then it seems you are still saying that it has a definite location (center?) that is a point.  So does this non-point particle have a definite point location and definite momentum?

(In classical mechanics you can consider an electron to be a point particle.  Much useful physics can be done in the classical domain.  But classical physics can't resolve things at subatomic scales.)

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Quote from: me

Follow some links, and quotes from them, taken from wikipedia, which arguably can be a doubtful source, yet below the articles there are references that can be of a more respectable group, perhaps.


Quote from: http://en.wikipedia.org/wiki/Elementary_particle
"In particle physics, an elementary particle or fundamental particle is a particle not known to have any substructure,[1] thus it is not known to be made up of smaller particles. If an elementary particle truly has no substructure, then it is one of the basic building blocks of the universe from which all other particles are made. In the Standard Model of particle physics, the elementary particles include the fundamental fermions (including quarks, leptons, and their antiparticles), and the fundamental bosons (including gauge bosons and the Higgs boson).[2][3] Although elementary particles are not made up of smaller particles, some of them may change to lighter particles (according to specific rules).

Historically, the hadrons (mesons and baryons such as the proton and neutron) and even whole atoms were once regarded as elementary particles (indeed, the word "atom" means "indivisible"). A central feature in elementary particle theory is the early 20th century idea of "quanta", which revolutionized the understanding of electromagnetic radiation and brought about quantum mechanics. For mathematical purposes, elementary particles are normally treated as point particles, although some particle theories such as string theory posit a physical dimension."


Quote from: Sue
I'll agree.  If you are working at the classical level you can treat a 'particle' as a point.  But when you burrow down trying to find the exact where or exact when or the exact how-fast you can't ignore QM.

Sue, the articles is clear, and they are not talking only classicale, it even, says that String theory, possits dimmensions as something out of the norm.

The mathematical treatment is clearly stated : " as a point particle".


I disagree that they are not talking about the classical level.

And I thought you agreed above that a particle itself is not a point.  Please clarify.

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{snip}

Quote from: Sue
That makes my point.  "Even an elementary particle, with no internal structure, occupies a nonzero volume."  "Elementary particles are sometimes called "point particles", but this is in a different sense than discussed above."

You are picking up what you want to read, sorry. I never said they can not occupy a volume. I said they are treated mathematically as point particles, and that the discrete values that characterize them as charge, spin and the more are considered to be localized where the particle is positioned.


And I might say you are not picking up what you don't want to read.

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{snip}


Quote from: Sue
In the informal and classical physics sense of 'particle' I would agree.  But I argue that QM describes inescapable facts of nature that are simply masked at the macroscopic level of observation.

Wikipedia is not the top of the line when it comes to references, but I am providing references, you are just denying them, perhaps, you can provide some references of your own.


I may cite other references but your references are generally good.  They serve my point perhaps better than you realize.  (You seem to accept HUP.)   I'm not denying your references.  I am challenging your interpretation.

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Quote from: me
My impresion is that the mathematical model assumes those values are located at that specific position, on that specific particle, but If I had to guess , this would be a mathematical approximation. I am not sure.



Your impression is incorrect.  Schroedinger's Equation and the wavefunction are the mathematical model.  They quite explicitly do not assume that the mass and charge of a quantum are at a specific position.


Quote from: me
I think you are confusing the definition of a particle and its mathematical treatment, and the use of the Schrodinger equation to determine a particle´s energy states.


Quote from: Sue
I'll partially agree with you here.  There is confusion but it is not about "the definition" but more about which definition.  You have cited numerous examples with different senses.  (I applaud you for your research.)  In classical physics one can say the 'particle' is at x = 3.  But when one tries to resolve x exactly it breaks down before one approaches the Planck length.  (If I am wrong please show me a counterexample.)

It does not brake down, it just has an intrinsic uncertainty at the measurement level ( from the point of view of  epistemollogy ), not at the ontological level, at least not necessarily ( nobody really knows ) , some interpretations support the former and others the latter. But, You can say the particle is at x=3 with an uncertainty DeltaX. There is uncertainty, but that is a long way from saying that something is P and not P, which is what you were arguing originally.


Classical physics breaks down at the quantum level.  There's no two ways around that.  You will find no one that can give a coherent contrary argument.

If "nobody really knows" there is no ontology.

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I think I have cited some interesting references. I can look for one, but I would like to comeback to the actual point of all this. Your statement that quantum mechanics proves logic wrong, that the wave-particle effect denies logic, it doesn´t, I said in one of my post, that what ever physicists call a particle is one thing, whatever its behavior is, it is only one thing, not two.


No, I don't say that QM proves logic wrong.  I say that the supposed "law of non-contradiction" is a simplification that is not consistent with all of reality.

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Quote from: Sue
Based on your citations: Does a 'particle' always have one definite true position?  (Your answer is 'Yes', isn't it?)  Is all the charge and mass of the particle at that one location?   (Your answer is 'Yes', isn't it?)  What path does an electron particle follow in orbiting a proton?



There are several , very specific, energy levels an electron can occupy around a hydrogen nucleus ( a proton), that is the path they follow.


Incomplete and ambiguous.  An energy level is not a position.

You sorta answered about charge and mass above.

You more or less ignored the 'path' question.  (An energy level is not a path.)

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Quote from: Sue
If you need to use Schroedinger's equation or differential equations in general, go ahead.  I'm pretty sure I can keep up with you.

LOL. I actually consider that a  nice compliment. I did work with the Schrodinger equation 20 years ago in college, I probably could do something like the Schrodinger on a well of potential , but I am not even sure I could do it with out picking the documentation. I don´t think we need to go that far, perhaps another post. But thanks.


Quote from: me

Take a look at the articles I quoted above:

The electron has no known substructure.[2][72] Hence, it is defined or assumed to be a point particle with a point charge and no spatial extent.

 For mathematical purposes, elementary particles are normally treated as point particles



Quote from: Sue
Is there any incorrect logic?  Does anyone ever hold to something as 'logic' but which is actually incorrect?  Wasn't it once a mater of logic that "nature abhors a vacuum"?  Wasn't it once a mater of logic that heavier things fall faster.  Wasn't it once a mater of logic that "that which goes up must come down"?  Was it self defeating to argue against those ideas?

Quote from: me
You are again, confusing things: I can recognize some of those assertions, as coming from the writings of Aristotle, and they are from his "book" called physics ( At least in Spanish : Física), they do not come from his studies on syllogisms, which were the first studies on logic, If I recall correctly, two quite different studies. And these studies were made 2300 years ago. Perhaps we can cut a break for Aristotle.

Quote from: Sue

Special pleading?  We must forgive Aristotle's work for failing progressive consistency checks but we may not apply progressive checks to the supposed "law of non contradiction"?


LOL, again you misconstrue, what I say.  Noticed that I asserted that Aristotle logic, 2300 years later is just fine:
"It is worth to say that Aristotle logical syllogisms are still valid, today. "


It's getting late in the day for me.  I owe you a response to the below too I think.  There seem to be some interesting points.  But I think I'm going to have to call it quits for now.
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