Quantum Mechanics: Paradoxical?

[Mentat]

First let me define my use of the word paradox, in this thread. A paradox is a self-contradictory statement, or one that cannot be true, but also cannot be false.

Alright, now, some have said that Quantum Mechanics meets this criteria, because it states that something can be both alive and dead at the same time. If this is what it said, then I would agree that it was paradoxical, because "dead" is the opposite of "alive" and so you cannot be both.

However, it is my current opinion that that is not what QM implies. I have read that Schrodinger's (sp?) Cat is not alive or dead, it is 1/2 of each. It is in a half-way state, until an observation is made, and then it becomes one or the other.

Is my understanding of "Schrodinger's Cat" correct. If not, is Quantum Mechanics paradoxical?

 

[heusdens]

Originally posted by Mentat
First let me define my use of the word paradox, in this thread. A paradox is a self-contradictory statement, or one that cannot be true, but also cannot be false.

Alright, now, some have said that Quantum Mechanics meets this criteria, because it states that something can be both alive and dead at the same time. If this is what it said, then I would agree that it was paradoxical, because "dead" is the opposite of "alive" and so you cannot be both.

However, it is my current opinion that that is not what QM implies. I have read that Schrodinger's (sp?) Cat is not alive or dead, it is 1/2 of each. It is in a half-way state, until an observation is made, and then it becomes one or the other.

Is my understanding of "Schrodinger's Cat" correct. If not, is Quantum Mechanics paradoxical?

The example you use (Schodingers cat) is an interpretation of Quantum physics that is not supported by all physicists. Why would the cat depend on it being observed before it can be determined if the cat would be alive or not. Why hasn't the cat itself observer states? etc.

I think it is an uneasonable interpretation of quantum physics. Quantum physics takes place in the micro universe, and not in the macro universe. If this interpreation would be true, then it leads to several other paradoxes. For instance the observer that first sees the cat, would determine by his/her observation (the collapse of the wave function) if the cat is alive or not. But why wouldn't the observer itself be in a same kind of state as the cat and the experiment itself. Being halfway observing a dead cat, and halfway being observing a life cat. And so on.

For this obvious reasons, this kind of interpretation is assumed wrong.

 

[quantumdude]

One important point is being missed here.

"In his original thought experiment, Schrodinger imagined that a cat is locked in a box, along with a radioactive atom that is connected to a vial containing a deadly poison. If the atom decays, it causes the vial to smash and the cat to be killed. When the box is closed we do not know if the atom has decayed or not, which means that it can be in both the decayed state and the non-decayed state at the same time. Therefore, the cat is both dead and alive at the same time - which clearly does not happen in classical physics."

Originally posted by heusdens
But why wouldn't the observer itself be in a same kind of state as the cat and the experiment itself.

Because the observer is not coupled to a quantum mechanical system that can kill him (namely, a radioactive atom).

edit:

The above makes me wonder: Why introduce the cat at all?

I mean, the state of the cat is supposed to be analogous to quantum mechanical wave functions, but the fate of the cat is controlled by none other than a quantum mechanical wave function of a radioactive nucleus! Why not just look at that directly?

 

[heusdens]

Originally posted by Tom
One important point is being missed here.

"In his original thought experiment, Schrodinger imagined that a cat is locked in a box, along with a radioactive atom that is connected to a vial containing a deadly poison. If the atom decays, it causes the vial to smash and the cat to be killed. When the box is closed we do not know if the atom has decayed or not, which means that it can be in both the decayed state and the non-decayed state at the same time. Therefore, the cat is both dead and alive at the same time - which clearly does not happen in classical physics."



Because the observer is not coupled to a quantum mechanical system that can kill him (namely, a radioactive atom).

edit:

The above makes me wonder: Why introduce the cat at all?

I mean, the state of the cat is supposed to be analogous to quantum mechanical wave functions, but the fate of the cat is controlled by none other than a quantum mechanical wave function of a radioactive nucleus! Why not just look at that directly?

Yes, but the cat is an observer. Would it be different if the cat were a human? The cat observes, prior to possible being killed, the espace of gas or not. So, why wouldn't that collapse the wave function?

And the explample of the (second) observer, opening the box, that would suppose in this example to cause the collapse of the wave function. Why only then? It can be argues as well, this observer then becomes part of and connected to the system in a dual state, and becomes part of that dual state: observing a dead cat or observing a life cat.

 

[wuliheron]

Quantum physics takes place in the micro universe, and not in the macro universe.

This statement is not quite correct either. Bose-Einstein condensates, for example, have been created which incorporate hundreds of molecules. What seems to matter is the extremes of the situation, not simply size. At extremely cold temperatures, high energy levels, small sizes etc. quantum effects can be observed in any system. According to calculations and observations, certain neutron stars displays Quantum effects on a truly large scale.

As for Shrondenger's Cat, that is merely one effect of the central paradox of Quantum Mechanics, the Uncertainity Principle. This couples all the observable characteristics of particles in ways which make no common sense whatsoever. Mass and momentum, spin and momentum, etc. are all intimately connected so that it is impossible to effect one without effecting the other.

What's more, this effect is precisely balanced and not simply arbitrary. If a flying ball hits a wall it may fall to the floor resting in one spot while still spinning, but not so with Quanta. The energy they contain, including their momentum, is quantized.

This a bit along the lines of Zeno's paradox. If I take a step and then half of that and so on I will never reach my destination. However, Quantum Mechanics demonstrates it is impossible past a certain point to further subdivide my steps. What's more, as something influences my steps it also influences everything else about me.

Some have suggested that what Quantum Mechanics really describes are really waves, that everything is made out of waves of energy and this explains how influencing one characteristic of a "particle" effects all the others. However, ordinary waves can theoretically be infinitely subdivided and do not display both the properties of a particle and a wave.

Is it mass, is it energy, is it a particle, a wave, alive, dead, a thing, or a non-thing? No one can say for sure. Thus they are described as Indeterminate and paradoxical. All that can be said for sure is they obey stritch rules of indeterminacy which defy everyday experience.

As for the "observer" and Shrondenger's Cat observing itself, recent experiments suggest it is not so much an observer collapsing the wave function but environmental noise. The state of somehow alive and dead last for perhaps a few femto seconds until environmental noise effects it. In other words, the weird indeterminate state of quanta increases with isolation, yet another extreme.

 

[heusdens]

Originally posted by wuliheron
As for the "observer" and Shrondenger's Cat observing itself, recent experiments suggest it is not so much an observer collapsing the wave function but environmental noise. The state of somehow alive and dead last for perhaps a few femto seconds until environmental noise effects it. In other words, the weird indeterminate state of quanta increases with isolation, yet another extreme.

That is what I think indeed happens. The kind of interpretation this experiment initially was given, serves a philosophical viewpoint of Idealism (which states that an objetive outside reality does not exist, and is dependend on the mind/observer). However, any observation is an act of "the flesh" not of "the mind", and thus does not raise the kind of paradox suggested here.

 

[wuliheron]

That is what I think indeed happens. The kind of interpretation this experiment initially was given, serves a philosophical viewpoint of Idealism (which states that an objetive outside reality does not exist, and is dependend on the mind/observer). However, any observation is an act of "the flesh" not of "the mind", and thus does not raise the kind of paradox suggested here.

No, it doesn't raise the kind of paradox referred to here, but it doesn't discount it either or that of the Hegelians' fascination with infinity either. If anything, it focuses the discussion more on seriously self-referential and self-contradictory paradox itself.

Ninty five percent of all the scientists that have ever lived, are alive today. Despite this and the inordinate amount of money spent on science, the paradox of existence has only deepened. Thus it presents a ground for simultaneously unifying all these disparate views and placing them at odds to each other. In other words, progress as we've come to know the meaning of the word. :0)

 

[with.buddha]

i like the noise theory, it makes sense.. but the many-worlds theory should be mentioned.

let's say we are all together when we set up the box.. everybody leaves and I'm the first one back after an hour. I'm so curious, i open the box and find the cat dead - theoretically collapsing the wave-function and "making" the cat dead. then i seal the box again.

i leave and someone else comes back and opens the box - the cat will be dead. BUT the 2nd person didn't collapse the wave-function... i did.

the many-worlds theory allows for this, and also allows for the cat to act as an observer by stating that all potentialities actually do exist and we are constantly splitting paths.. like, the "you" that almost got hit by a car actually did get hit by a car in MANY other "worlds", but the "you" that is sitting here now is your current reality.

it's crazy, but not impossible. as my username suggests, I'm into buddhism and this theory fits nicely with the philosophy..

it's almost like your consciousness is a bubble surfing through this one set of many-worlds and when you die, you could be born again in a this "world", but that world would diverge depending on how you choose to live.

it's like a video game where you play over and over again and can sometimes follow similar paths and sometimes play a completely different character..

i hope i made sense, i haven't slept in awhile.. but this theory is one that has come up to eliminate the paradox..

but, like i said, the environmental noise theory sounds much more realistic...

 

[Fliption]

Originally posted by heusdens
Yes, but the cat is an observer. Would it be different if the cat were a human? The cat observes, prior to possible being killed, the espace of gas or not. So, why wouldn't that collapse the wave function?

And the explample of the (second) observer, opening the box, that would suppose in this example to cause the collapse of the wave function. Why only then? It can be argues as well, this observer then becomes part of and connected to the system in a dual state, and becomes part of that dual state: observing a dead cat or observing a life cat.

heusdens,

I think you are not understanding the intent of the experiment. I agree with Tom. It didn't need to be a cat. It could have been anything. The point of this thought experiment was to show how absurd the copenhagan interpretation was. It was an attempt to link the weird events in the quantum world with the classical world that we know, to illustrate the absurdity. The fact that the macro world object was a cat, which can be argued to be conscious, has nothing to do with the experiment at all.

 

[RuroumiKenshin]

Personally, I think Tom really cleared the whole matter, with the analysis he presented with the excerpt from the book.

Further, I should like to make clear the fact that for one, cats, including any other living thing under the curse of death, is dying. Yet, a "living thing" is considered to be alive, although it is dying ("dying" should not be misconstrued to be portending a future event, but it should contrued to specify a present state). So, I guess with such minute reasoning, one can conclude it is vaguely possible to be "alive and dead" at the same time?(not rhetorical)

 

[jammieg]

Is this experiment demonstrating
that in quantum mechanics things
are too small and moving too fast to
"open the box" and see atoms dead and
alive all the time? Is it that they say the
cat is half dead and half alive to mean
that we can't see all the atoms all the time so we give them probabilities and possibilities? If so I think it's a very round about way of saying this.

 

[RuroumiKenshin]

Welcom to PFs

Didst thou read this, Jammieg? (forgive me if I have mispelled your screen name). I think Tom's post explains it very well.

Originally posted by Tom
One important point is being missed here.

"In his original thought experiment, Schrodinger imagined that a cat is locked in a box, along with a radioactive atom that is connected to a vial containing a deadly poison. If the atom decays, it causes the vial to smash and the cat to be killed. When the box is closed we do not know if the atom has decayed or not, which means that it can be in both the decayed state and the non-decayed state at the same time. Therefore, the cat is both dead and alive at the same time - which clearly does not happen in classical physics."

 

[ahrkron]

Originally posted by wuliheron
As for the "observer" and Shrondenger's Cat observing itself, recent experiments suggest it is not so much an observer collapsing the wave function but environmental noise.[/B]

Are you talking about decoherence? AFAIK, no experiment can be interpreted as supporting such idea. It is an interesting interpretation, I agree, but its predictions do not differ from those of any other interpretation of QM (since the formal machinery is the exact same one).

 

[ahrkron]

Originally posted by Tom
Because the observer is not coupled to a quantum mechanical system that can kill him (namely, a radioactive atom).

Why is it not coupled?

Both the cat and the observer are aggregates of a very big number of quantum systems, each of which follows the rules of QM (unitary evolution).

Think of the wavefunction associated to such aggregate (the "wavefunction of the observer"). After opening the box, such wavefunction will have very different spacetime probability distributions: in one case it will have a big probability of smiling, and of feeding and playing with a cat after the experiment; on the other, such probability is zero.

While the box is closed, the wavefunction for the radiactive atom is such that

|state at probing time> = |decayed> + |notDecayed>

The cat+atom system is set so that its state rigth after that time is

|decayed,dead> + |notDecayed,alive>

And the cat+atom+observer system is such that, once opening the box, it should be

|decayed,dead,grieving> + |notDecayed,alive,playingWithCat>

However, our perceptions apparently show that, at some point, the system went from the above state to one described by only one of the two terms.

It is not just a matter of knowing vs not_knowing, since quantum superposition does have physical effects (as in the double slit experiment).

The above makes me wonder: Why introduce the cat at all?

Just for the dramatic effect it has. People may have no problem with an atom behaving in an odd way, but having a half-alive, half-death animal was better for Schrodinger to make people think twice about the Copenhagen interpretation.

We can also think about arranging the experiment so that, if the cat dies, a city is built in his name; if not, then a cruise ship is built for the cat to take a vacation.

The QM description of the full system after 10 years would then be

|decayed,dead,grieving,CatCity> + |notDecayed,alive,playingWithCat,USSfelineVacation>

Or isn't it? did the first observer collapse it? the cat? the construction workers? why?

An observer who stayed in Australia for those ten years would describe the full system as a superposition (why would he stop the unitary evolution description?), and yet, once he returns to LabCity, the state has to be described by only one of those terms.

If those terms could interfere, then a "double slit experiment" would be able to show a physically real interference pattern on a TV screen until the moment he looks at the result; from then on, the interference pattern would dissappear, and he would see only a big spike in the slit corresponding to, let say,

|notDecayed,alive,playingWithCat,USSfelineVacation>

 

[Mentat]

I thank you all for your replies.

However, no one has yet answered the real question of this thread: Is "Schordinger's Cat" paradoxical?

with.budda, I like that you brought the many-worlds idea, because that seems to resolve this problem. In the many-worlds reality, there is not paradox.

 

[wuliheron]

So... a cat being both alive and dead, a particle being also a wave, mass being energy, etc. all based on the most accurate physical theory in history which no one can say exactly what the theory is about...is not paradoxical. This is rhetorical nonsense that flies in the face of science and philosophy.

 

[ahrkron]

Originally posted by Mentat
First let me define my use of the word paradox, in this thread. A paradox is a self-contradictory statement, or one that cannot be true, but also cannot be false.

Is my understanding of "Schrodinger's Cat" correct. If not, is Quantum Mechanics paradoxical?

If we use words in a loosely defined manner, then it is easy to form phrases like

"According to QM, the atom has decayed and has not decayed"

Which is a blatantly self-contradictory statement. However, such description is a childishly oversimplifying rendering of what QM actually says about the state!

It is analogous to going from: "You have a wet tongue and a dry skin" to a cheating description like "you are dry and wet", and then happily saying "you are paradoxical!".

QM is definitely not paradoxical in the predictions it makes. If it was able to produce mutually contradicting predictions, it would have no use as a physical theory.

Much to the contrary, the theory is extremely well defined, and it clearly states what we will find out of an experiment.

The problem comes when people try to describe the outcome in terms of everyday-life words, which are of course derived from everyday-life objects and interactions.

Instead of saying "it is a paradox, as everything else... beware the power of paradox!", I find it much more useful to try and understand the subtleties in the process of translating measurements into interpretations. Such approach sheds light on the understanding of the subatomic world, the process of assigning descriptions, and the construction of interpretations, instead of stopping at the awe produced by a "paradox" based on ambiguous concepts, imprecise meanings and incomplete descriptions.

 

[wuliheron]

QM is definitely not paradoxical in the predictions it makes. If it was able to produce mutually contradicting predictions, it would have no use as a physical theory.

If you are going to be picky about semantics and use of the word paradox, you should be careful yourself. What you are talking about the application of the theory, not the theory itself or what it describes.

 

[ahrkron]

Originally posted by wuliheron
What you are talking about the application of the theory, not the theory itself or what it describes. [/B]

Despite popularization books, QM is a physical theory. It does not ever talk about dead cats and paradoxical decayed-and-not atoms. It has to do with physical states, Hilbert spaces, probabilities and experimental predictions. There are no inconsistencies or "paradoxes" in it.

What you may be referring to are the informal descriptions portrayed on popularization books and tv programs, in which the puzzling aspects (what you may call "paradoxical features") of the theory are strongly emphasized in order to keep the attention of the general public.

As I said, these "paradoxes" are just the result of a faulty description.

The theory does reflect the fact that microscopic ojbects behave in a way that conflicts daily life notions, but why would you expect otherwise?

 

[wuliheron]

This "popular" misconception you speak of extends to the greatest founding members of the theory including Heisenburg, Einstein, and Feignman and extends to such renouned institutions as Standford univeristy. Deny it all you want, it is widely recognized within scientific and academic circles.

The mathematics of the Hilbert spaces, probabilities, and predictions you speak of are based on paraconsistent logic
( http://plato.stanford.edu/entries/logic-paraconsistent/ ) repleate with contradictions which defy classical Aristotelian logic. Hence, QM is considered a break from classical physics and is referred to as modern physics.

To contest these facts is as absurd as the theory itself is.

 

[ahrkron]

Originally posted by wuliheron
This "popular" misconception you speak of extends to the greatest founding members of the theory including Heisenburg, Einstein, and Feignman

(minor correction: Heisenberg, Feynman)

They all gave serious thought to the interpretation of QM, and none of them gave up by saying "gee, it is just a paradoxical theory, let's leave it at that".

Deny it all you want, it is widely recognized within scientific and academic circles.

Exactly what do you say is "widely recognized"?
That the theory is self-contradictory? that it is a "paradoxical theory"?

It is widely recognized that its interpretation breaks some rules that hold in macroscopic physics, and that different interpretations exist for it, all of which were obtained from the same formalism.

The mathematics of the Hilbert spaces, probabilities, and predictions you speak of are based on paraconsistent logic

No, they are not. I have taken six courses on QM and QFT (one of which was precisely about t he interpretation of QM). Paraconsistent logics are not needed in the least to develop Hilbert spaces. They are a perfectly consistent, paradox-free piece of math, very much like any vector space.

Hence, QM is considered a break from classical physics and is referred to as modern physics.

It is, but not because it is "full of contradictions" as you try to portray it.

 

[wuliheron]

They all gave serious thought to the interpretation of QM, and none of them gave up by saying "gee, it is just a paradoxical theory, let's leave it at that".

Many have accused Bhorr of just the opposite, of making questioning the theory heresy, but this is off the subject. The subject is not whether we should or shouldn't look for alternatives, the subject is whether what we have today is paradoxical or not.

Exactly what do you say is "widely recognized"?
That the theory is self-contradictory? that it is a "paradoxical theory"?

It is widely recognized that its interpretation breaks some rules that hold in macroscopic physics, and that different interpretations exist for it, all of which were obtained from the same formalism.

By widely recognized I mean this is the scientific and academic consensus at this time.

The current understanding of the philosophical implications of the theory rest in particular on Bell's Theorem. Essentially he demonstrated any explanation for the theory must be nonlocal and defy causality. This is not say a reasonable explanation will never be discovered, just that the current theory is paradoxical and defies logic.

Exactly what QM describes is the huge debate that has raged since its inception. How it describes phenomena is not debated, it describes them in contradictory terms. Effects without causes are a paradox, a particle that is also a wave, is a paradox.

No, they are not. I have taken six courses on QM and QFT (one of which was precisely about t he interpretation of QM). Paraconsistent logics are not needed in the least to develop Hilbert spaces. They are a perfectly consistent, paradox-free piece of math, very much like any vector space.

Duh! What you still seem intent on obfuscating and avoiding is that their use within the theory of QM incorporates paraconsistent logic. Follow the link to Stanford I provided and see for yourself if honesty and integrity mean anything to you and you are so mathematically literate.

 

[drag]

Greetings !

I'm afraid I'll have to agree with ahrkron here.
Despite the fact that QM has basic principles
that are different from those in classical
physics and do not seem to fall under our
definition of "normal" applied logic it can
be represented by a different reasoning system.

Such terms as instant action and uncertainty that
were "ruled out" since the times of ancient Greece
are still no more paradoxical than any other
in a Universe that has the paradox of existence
as an unsaprable part.

However, it should be noted that the attempt to
settle our seemingly real reasoning system with
that of QM does lead to unsolvable problems (so far).
Which also means that the attempt to use QM
in its role as a physical theory to explain our
"reality" does lead to paradox in such an interpretation.

And yet, "reality" is paradoxical in many other ways
too so - who cares as long as the predictions are
correct ?

Live long and prosper.

 

[ahrkron]

Glad to see that you have changed you position from

The mathematics of the Hilbert spaces, probabilities, and predictions you speak of are based on paraconsistent logic

to

The mathematics of the Hilbert spaces ... incorporates paraconsistent logic.

Which is clearly a much less commited statement. "Incorporates" can be interpreted as anything from "introduces unavoidably" to "includes a loose resemblance to".

It is precisely this kind of ambiguity in the use of language that I am referring to. When a quantum state is described as a superposition of two different states, it is easy to form phrases like "it is spin up and down at the same time!". This may suit the goal of making things look strange and "paradoxical", but it is a very bad description. What actually happens has nothing paradoxical into it. The state is such that it has components from the two spin states, and a measurement will project the state into one of them.

QM is internally consistent. That is "widely recognized".

Follow the link to Stanford I provided

I did. It mentions Bohr's theory of the atom as an example in which paraconsistent logic can be applied. Does that mean that modern QM is self contradictory? no, since Bohr's model was incomplete and "patched" together, incorporating components from classical and the then incipient quantum mechanics.

and see for yourself if honesty and integrity mean anything to you and you are so mathematically literate. [/B]

Stick to content.

 

[wuliheron]

Obviously no integrity or honesty in your content. Nothing but more obfuscation, misdirection, and general BS.

 

[drag]

Greetings !

Originally posted by wuliheron
Obviously no integrity or honesty in your content.
Nothing but more obfuscation, misdirection, and
general BS.

temper... temper... wuliheron !
What's so paradoxical about QM that
distinguishes it ? The occasional lack of proper
cause and effect connections for example ?
So when every cause has an effect it is "reasonable" ?
Well let's see: cause & effect, cause * effect, cause &...
Wait a minute ! What's the first cause ?! What's the
last effect ?!
QM is no more and no less paradoxical than our
"normal reasoning". So, what IS your point ?

Live long and prosper.

 

[ahrkron]

Essentially he demonstrated any explanation for the theory must be nonlocal and defy causality.

Which means that its behavior is (very) different from that of macroscopic objects, a reasonable thing to expect.

This is not say a reasonable explanation will never be discovered

What would you consider a "reasonable explanation"? one in which the fundamental constituents of matter are seen to obey the same laws that we are trying to explain?

The search for those fundamental constituents stems precisely from the need to explain those laws in terms of others. It would be naive to assume that the ultimate constituents of a rock (and their behavior) are just smaller versions of the same rock, ad infinitum. There is most probably a lowest limit, and objects of that realm can be reasonably expected to have a much different behavior.

just that the current theory is paradoxical and defies logic.

Only if you define "logic" as "those things that one expects of macroscopic objects"

Exactly what QM describes is the huge debate that has raged since its inception.

Yes, but the existence of such debate does not mean that the theory is self-contradictory. Also, none of the interpretations assume or find (much less proof) that the theory is "paradoxical".

There are different interpretations, yes, but all of them are self consistent (or at least try to be). The problem is similar to that of relativity: it is far from everyday-life experiences. The way people obtain paradoxes in QM (and SR) is by confronting the predictions of the theory with the "logic" of classical mechanics.

How it describes phenomena is not debated, it describes them in contradictory terms.

Again, "contradictory" when you try to use classical mechanics for the description.

Effects without causes are a paradox

Yes, by the definition of "cause" and "effect". But, how does such statement apply to QM?

a particle that is also a wave, is a paradox.

Only because, classically, people use to think that objects are either waves or particles, but quantum objects are neither exclusively.

Here is why: when we say "particle" or "wave" in the context of QM, we refer to a certain characteristic of the state. In everyday life, we are used to find objects that are either totally-wave or totally-particle.

This would be as if every object you ever knew was either a square or a circle. You would probably think that it is a "logical necessity" that everything should be either one or the other.

However, you some day find a cylinder. From the top, it is a circle, but it is also a square if you look at it from the side.

Is that a "paradoxical" object? would you say then that the geometry of cylinders is a "paradoxical theory"?

I would rather say that the square-cylinder logic is incomplete as a result of a limited range of observations, and that the statement

"a square that is also a circle, is a paradox"

does not contribute much to the understanding of the cylinder phenomenon.

 

[wuliheron]

Originally posted by drag
Greetings !

temper... temper... wuliheron !
What's so paradoxical about QM that
distinguishes it ? The occasional lack of proper
cause and effect connections for example ?
So when every cause has an effect it is "reasonable" ?
Well let's see: cause & effect, cause * effect, cause &...
Wait a minute ! What's the first cause ?! What's the
last effect ?!
QM is no more and no less paradoxical than our
"normal reasoning". So, what IS your point ?

Live long and prosper.

You are correct of course that everything can be viewed as paradoxical, but this defeats the usefulness of logic which is demonstrable. Therefore we choose a starting point and an end point for logical arguments. We impose limits upon words and discussions for the sake of practicality.

An effect without a cause is what is commonly called magic, the supernatural, or absurd. Logic and reason are both founded upon the concept that some things are just patently absurd (note: an imposed limit) and paradoxes are one of these.

A cause without an effect is about as paradoxical as anything ever gets, a rudamentary paradox that defies the principle of synergy. It is the equivalent of saying you can have an up direction without a down, an outside without an inside, etc. or in other words, anything is possible.

 

[quantumdude]

Originally posted by wuliheron
Obviously no integrity or honesty in your content. Nothing but more obfuscation, misdirection, and general BS.

Lose the attitude.

Ahrkron is right. I printed out that "Paraconsistent Logic" article the first time you pointed it out to me, and I read it. It talks about the Bohr model, which is a Frankenstein-monster put together from classical mechanics and classical EM. The mechanical side predicts a stable solar system model, whereas the EM side predicts that such an orbit must be unstable. The bolts holding the two parts together is the ad hoc hypothesis: Allowed orbits are nonradiating.

That is indeed paraconsistent logic, but it is not quantum mechanics.

 

[wuliheron]

Originally posted by ahrkron

There are different interpretations, yes, but all of them are self consistent (or at least try to be). The problem is similar to that of relativity: it is far from everyday-life experiences. The way people obtain paradoxes in QM (and SR) is by confronting the predictions of the theory with the "logic" of classical mechanics.

The person who started this thread defined paradox in terms of the classical Aristotelian definition of the word. A quanta cannot be considered true or false by this definition, hence it is paradoxical.

 

[ahrkron]

Originally posted by wuliheron
The person who started this thread defined paradox in terms of the classical Aristotelian definition of the word. A quanta cannot be considered true or false by this definition, hence it is paradoxical.

?

In any logic (Aristotelian or otherwise), a noun cannot be "true" or "false". I'm not sure what you meant to say.

In any case, Mentat posted

First let me define my use of the word paradox, in this thread. A paradox is a self-contradictory statement, or one that cannot be true, but also cannot be false.

and asked if QM is paradoxical.

QM does not contain self-contradictory statements; hence, it is not paradoxical.

 

[quantumdude]

Originally posted by Mentat
First let me define my use of the word paradox, in this thread. A paradox is a self-contradictory statement, or one that cannot be true, but also cannot be false.

Wuli, the classical Aristotelian definition of the word implies that we are focusing our attention on a subset of the set of statements. Quanta are not even on the table here.

 

[wuliheron]

Wuli, the classical Aristotelian definition of the word implies that we are focusing our attention on a subset of the set of statements. Quanta are not even on the table here.

Yes, you are correct. Sorry about.

In any logic (Aristotelian or otherwise), a noun cannot be "true" or "false". I'm not sure what you meant to say.

What I meant to say is that QM describes that which is neither true nor false, but the Indeterminate or absurd.

QM does not contain self-contradictory statements; hence, it is not paradoxical.

A cat being both alive and dead at the same time is self-contradictory and is neither true nor false, real or unreal. By classical standards of logic and classical definitions of the word paradox, which is being used here, it is an absurdity.

The author of this thread did not ask if QM is self-consistent alone, but whether it fits the classical definition of paradox and the absurd which it most definitely does.

 

[Mentat]

Thanks very much for the responses. As I see it, I'm going to have to much more research into Quantum Theory. Fortunately, I like that!

 

[Mentat]

Originally posted by wuliheron

A cat being both alive and dead at the same time is self-contradictory and is neither true nor false, real or unreal. By classical standards of logic and classical definitions of the word paradox, which is being used here, it is an absurdity.

The author of this thread did not ask if QM is self-consistent alone, but whether it fits the classical definition of paradox and the absurd which it most definitely does.

Well, actually, I did ask if it was self-contradictory. As you know, that's my favored definition of "paradox". I think you are absolutely correct, that QM could be considered "absurd" by classical reasoning, and thus it is, in one form, paradoxical. But, I meant the self-contradictory type of "paradox".