(January 7, 2009 at 1:47 pm)josef rosenkranz Wrote: Therefore I asked an din't get a clear answer if the Casimir effect means
the creation of an event out of nothing previous ,which was my understanding of your statement of "pure random",or it is the causal effect of some previous event.
The item of this thread is determinism vs. indeterminism ,(which in my view bears consequences related to aheism,even if some members of this forum disagree),so from this point of view I said that it would be interesting to learn from your knowledge about the Casimir effect.

I believe I've already answered that one, but to be clear: the current scientific model of it is that the creation of the virtual pair is uncaused and that the effect of the short-lived pair is real and measurable. On the other hand, in that same scientific model the effect requires the presence of space-time dimensions (the Heisenberg Uncertainty Priniple is applied to the vacuum within space-time). So there is a (possibly necessary) prerequisite but not a causal dependence (the vacuum can not be said in any meaningful physical sense to cause the events). I hope this somewhat clarifies it for you.

(January 7, 2009 at 1:47 pm)josef rosenkranz Wrote: I don't have the skill to deny anything about quantum mechanics and I didn't deny either the existence of the Casimir effect.
However as counterintuitive as a problem might be ,even in such a domain demanding high knowledge of physics,I don't believe that the essence of it is unaccessable to common wisdom.
Therefore I asked an din't get a clear answer if the Casimir effect means the creation of an event out of nothing previous ,which was my understanding of your statement of "pure random",or it is the causal effect of some previous event.

I'm not sure if this has been explained before, but...

There are particle-antiparticle pairs popping into and out of existence all around us (this is otherwise known as the 'quantum foam'). The Casimir effect is the force felt between two metal plates: they are so close together that fewer pairs can pop into existence between them than outside them. This means that more pairs are colliding with the plates on the outside than the inside, thus pushing the plates further together by a fraction.

Basically, the Casimir effect is where spontaneously generating particles push two metal plates closer together. Wiki has a good picture:


NB: 'vacuum fluctuations' simply means the fluctuations in a vacuum due to the spontaneously generating particles.

So yes, the Casimir effect is evidence of 'creation ex nihilo'

(January 7, 2009 at 1:47 pm)josef rosenkranz Wrote: The item of this thread is determinism vs. indeterminism ,(which in my view bears consequences related to aheism,even if some members of this forum disagree),so from this point of view I said that it would be interesting to learn from your knowledge about the Casimir effect.

Indeterminism is a simple consequence of the quantum mechanical nature of the universe: not only is it impossible to know the exact position and momentum of a particle, but it doesn't have an exact position and momentum until you try to measure it (measuring its position lets you know where it is with more accuracy, but lowers the accuracy with which you know its momentum. Mathematically, ΔxΔp ≥ ħ/2).

(January 8, 2009 at 8:17 am)DD_8630 Wrote:

(January 7, 2009 at 1:47 pm)josef rosenkranz Wrote: I don't have the skill to deny anything about quantum mechanics and I didn't deny either the existence of the Casimir effect.
However as counterintuitive as a problem might be ,even in such a domain demanding high knowledge of physics,I don't believe that the essence of it is unaccessable to common wisdom.
Therefore I asked an din't get a clear answer if the Casimir effect means the creation of an event out of nothing previous ,which was my understanding of your statement of "pure random",or it is the causal effect of some previous event.

I'm not sure if this has been explained before, but...

There are particle-antiparticle pairs popping into and out of existence all around us (this is otherwise known as the 'quantum foam'). The Casimir effect is the force felt between two metal plates: they are so close together that fewer pairs can pop into existence between them than outside them. This means that more pairs are colliding with the plates on the outside than the inside, thus pushing the plates further together by a fraction.

Basically, the Casimir effect is where spontaneously generating particles push two metal plates closer together. Wiki has a good picture:

NB: 'vacuum fluctuations' simply means the fluctuations in a vacuum due to the spontaneously generating particles.

So yes, the Casimir effect is evidence of 'creation ex nihilo'

(January 7, 2009 at 1:47 pm)josef rosenkranz Wrote: The item of this thread is determinism vs. indeterminism ,(which in my view bears consequences related to aheism,even if some members of this forum disagree),so from this point of view I said that it would be interesting to learn from your knowledge about the Casimir effect.

Indeterminism is a simple consequence of the quantum mechanical nature of the universe: not only is it impossible to know the exact position and momentum of a particle, but it doesn't have an exact position and momentum until you try to measure it (measuring its position lets you know where it is with more accuracy, but lowers the accuracy with which you know its momentum. Mathematically, ΔxΔp ≥ ħ/2).

You put it as if indeterminism is a consequence of a physical law.
I consider that more correctly is to say that the uncertainity principle is an expression of indeterminism, and even only a partial one.
In fact the difference between the Newtonian possibility of knowing the exact position of an object, knowing it's momentum and speed and the quantum mechanical possibility regarding a subatomical particle is only a statistical one.
That means that the position of the particle is not totally random but
predictable within some limits as expressed in the mathematical relation.
In other words the uncertainity principle is an expression of a dual form a physical laws including determinism as well as indeterminism.
Now,taking into consideration that the whole matter of the universe is made of atoms one can conclude that this duality of indeterminism and determinism is in fact a general law of matter.
If we leave the subatomic world and look around at our close experiences in classical physics or in other areas of human activity, governed by statistical laws, the same duality is most evident.
Each statistic law has at it's core a predictable relation ,conventionally limited, and beyond those limits the statistic becomes more and more random.

About the Casimir effect as a creation "ex nihilo" I still have my reserves because it is not only "counterintuitive" as Purple Rabbit put it in such a fine English expression but it is straight "antiintuitive" ,which may be the same but a little bit stronger as I see in your "ex nihilo creation".
I would not dare to contradict scientist who affirm the ex nihilo effect would we have more large knowledge about the antimatter,which we don't.
Physics is now blundering about the dark matter and I have not heard about any physicist of a high stature as Hawking,Penrose or others to have found the basic laws which govern antimatter.
So I would be more carefully by saying that the Casimir effect is "apparently " ex nihilo at the level of our knowledge about antimatter but that do not exclude the possibility to find in the future a still undisclosed causal phenomenon to it.
As an anecdote ,we know from history that the kings of the German dynasty of the Hohenzollern ,who ruled for a long time in Europe had this slogan written on their royal emblem "Nihil sine Deo" .
Putting together "Creation ex nihilo" with "Nihil sine Deo" we get
"Creation=Deo" q.e.d.

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: You put it as if indeterminism is a consequence of a physical law.
I consider that more correctly is to say that the uncertainity principle is an expression of indeterminism, and even only a partial one.
In fact the difference between the Newtonian possibility of knowing the exact position of an object, knowing it's momentum and speed and the quantum mechanical possibility regarding a subatomical particle is only a statistical one.
That means that the position of the particle is not totally random but
predictable within some limits as expressed in the mathematical relation.

Ah, no. It's not that quantum mechanics places practical limits on how accurate we can measure position, momentum, energy, etc, but rather that it a quantum particle truly does not have an exact position, momentum, etc. The Heisenberg Uncertainty Principle (ΔxΔp ≥ ħ/2, EΔt ≥ ħ/2, etc) is merely the mathematical representation of this quantum fuzzing of physical variables.

So it is not determinate insofar as you cannot determine what variable A is now, nor can you know what it will be. Indeed, because of these fuzzy positions, momenta, energy, etc, the particle's future position (such that it is) is random: its associated wavefunction assigns it future possible positions, but nothing determines where it will be.

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: In other words the uncertainity principle is an expression of a dual form a physical laws including determinism as well as indeterminism.

I disagree. At a stretch, you could say that quantum indeterminism approximates to classical determinism (as per the Bohr correspondence principle), but ultimately quantum mechanics does not incorporate determinism.

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: About the Casimir effect as a creation "ex nihilo" I still have my reserves because it is not only "counterintuitive" as Purple Rabbit put it in such a fine English expression but it is straight "antiintuitive" ,which may be the same but a little bit stronger as I see in your "ex nihilo creation".

But is that really a criticism? Yes, it would be nice it the world worked intuitively, but our brains evolved to scream at and have sex with those monkeys in the other tree. The subtleties of subatomic mechanics never affected our brains' evolution.

As Dawkins so finely put it, we live in 'middle world': too big to feel quantum effects, too small to feel complex gravitational effects, and too slow to feel relativistic effects. Classical mechanics is so appealing to us because that's all our brains had to cope with: to us, things might as well be purely classical.

Sadly, they're not .

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: I would not dare to contradict scientist who affirm the ex nihilo effect would we have more large knowledge about the antimatter,which we don't.
Physics is now blundering about the dark matter and I have not heard about any physicist of a high stature as Hawking,Penrose or others to have found the basic laws which govern antimatter.

It obeys the same laws as normal matter. Antimatter is just matter with the opposite electric charge: electrons (matter) and positrons (antimatter) are exactly the same, except their electric charges are opposite (-e and [/i]e[/i], respectively).

It's not mysterious. It's just hard to contain: it annihilates upon contact with normal matter.

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: So I would be more carefully by saying that the Casimir effect is "apparently " ex nihilo at the level of our knowledge about antimatter but that do not exclude the possibility to find in the future a still undisclosed causal phenomenon to it.

I exclude no possibility. Indeed, I have always thought that quantum mechanics would be superseded by something more refined, in much the same way that classical mechanics is superseded by quantum.

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: As an anecdote ,we know from history that the kings of the German dynasty of the Hohenzollern ,who ruled for a long time in Europe had this slogan written on their royal emblem "Nihil sine Deo" .
Putting together "Creation ex nihilo" with "Nihil sine Deo" we get
"Creation=Deo" q.e.d.

I bow to your impeccable logic, sir.

Quote:

Quote:So it is not determinate insofar as you cannot determine what variable A is now, nor can you know what it will be. Indeed, because of these fuzzy positions, momenta, energy, etc, the particle's future position (such that it is) is random: its associated wavefunction assigns it future possible positions, but nothing determines where it will be.

(January 9, 2009 at 1:00 pm)josef rosenkranz Wrote: In other words the uncertainity principle is an expression of a dual form a physical laws including determinism as well as indeterminism.

I disagree. At a stretch, you could say that quantum indeterminism approximates to classical determinism (as per the Bohr correspondence principle), buquote]So it is not determinate insofar as you cannot determine what variable A is now, nor can you know what it will be. Indeed, because of these fuzzy positions, momenta, energy, etc, the particle's future position (such that it is) is random: its associated wavefunction assigns it future possible positions, but nothing determines where it will be.

t ultimately quantum mechanics does not incorporate determinism.[/quote]

Here is a quotation from Stephen Hawking's book A brief history of time, chapter The uncertainity principle:
" In general quantum mechanics does not predict a single definite result
for an observation.Instead it predicts a number of different possible outcomes and tells us how likely each of these is".( unquote)

So quantum mechanics does predict outcomes but they are fuzzy as you put it.
May I ask on what base is this prediction done if not on physical laws which are per se an expression of determinism.The fuzzyness or the randomness of the outcomes is the second part of this equation expressed statistically or as Hawking puts it "how likely each of these is".
One can express that duality of determinism and indeterminism in many philosophical forms but one can not deny their simultaneous coexistence in the most basical laws of nature.

Here is another quotation from the same book ,the same chapter:
"We could still imagine that there is a set of laws that determines events completely for some supranatural being,who could observe the present state of the universe without disturbing it.However such models of the universe are not of much interest to us ordinary mortals.It seems better to employ the principle of economy known as Occam's razor and cut out all the features of the theory that cannot be observed.(unquote)

In his concise scientifical but also popular style Hawking cuts the limits of determinism and throughs the remainig features away to randomness.

That's,in other words, just the characteristics of statistical laws.
Let's take for instance a law which says :A+B =C, but where C has not a definite value but a statistical one of let's say 60%.
Now if we will repeat the experiment A+B for a 100 times we will get only in 60 cases the result C in at least 2 conditions:
- before each experiment we will not know if the result is exact C for the reason as put by Hawking ( in generally, not in the particular case of quantum mechanics)
-after achieving the value C in 60 experiments before the number of 100 the next results will be highly random.
Here we see the same dualty :the value C is predictable (say determined) for a certain number of experiments but is in the same time random for all the others.

I have used in this thread the case of the uncertainity principle only as a classical example for it's well known position in the debate over indeterminism without any pretention of competing with members who are skilled in the prolems of modern physics.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: Here is a quotation from Stephen Hawking's book A brief history of time, chapter The uncertainity principle:
" In general quantum mechanics does not predict a single definite result
for an observation.Instead it predicts a number of different possible outcomes and tells us how likely each of these is".( unquote)

So quantum mechanics does predict outcomes but they are fuzzy as you put it.
May I ask on what base is this prediction done if not on physical laws which are per se an expression of determinism.The fuzzyness or the randomness of the outcomes is the second part of this equation expressed statistically or as Hawking puts it "how likely each of these is".

Correct, but the subtlety is that the outcome is truly probabilistic: the universe doesn't 'know' what's going to happen until it does. It's not that particles have an unknown position, but rather that they don't have a position.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: One can express that duality of determinism and indeterminism in many philosophical forms but one can not deny their simultaneous coexistence in the most basical laws of nature.

Sure we can: determinism does not exist, insofar as quantum mechanics is concerned. You cannot determine the future with absolute accuracy because the fundamental rules that govern the behaviour of the universe and its contents are inherently probabilistic.

We can use mathematical formulae to describe probability distributions, but we still do not know the outcome of a trial until we run it.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: Here is another quotation from the same book ,the same chapter:
"We could still imagine that there is a set of laws that determines events completely for some supranatural being,who could observe the present state of the universe without disturbing it.However such models of the universe are not of much interest to us ordinary mortals.It seems better to employ the principle of economy known as Occam's razor and cut out all the features of the theory that cannot be observed.(unquote)

In his concise scientifical but also popular style Hawking cuts the limits of determinism and throughs the remainig features away to randomness.

In that case, I humbly disagree with Hawking's conclusion.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: That's,in other words, just the characteristics of statistical laws.
Let's take for instance a law which says :A+B =C, but where C has not a definite value but a statistical one of let's say 60%.
Now if we will repeat the experiment A+B for a 100 times we will get only in 60 cases the result C in at least 2 conditions:
- before each experiment we will not know if the result is exact C for the reason as put by Hawking ( in generally, not in the particular case of quantum mechanics)
-after achieving the value C in 60 experiments before the number of 100 the next results will be highly random.
Here we see the same dualty :the value C is predictable (say determined) for a certain number of experiments but is in the same time random for all the others.

Ah, no, that's not what 'determine' means. We can calculate the likelihood that a given outcome will occur, but we cannot determine whether it will actually occur or not (until we run the trial, of course).

We can say where an electron in a potential well is likely to be at some time t, but not where it will be. This is not because we don't have enough information, but rather the position of the electron is 'spread out' over all of space. Instead of it being at one particular place, it exists as a superposition of all possible positions. Until we measure it, whereafter things get complicated :p

(January 11, 2009 at 6:03 pm)DD_8630 Wrote:

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: Here is a quotation from Stephen Hawking's book A brief history of time, chapter The uncertainity principle:
" In general quantum mechanics does not predict a single definite result
for an observation.Instead it predicts a number of different possible outcomes and tells us how likely each of these is".( unquote)

So quantum mechanics does predict outcomes but they are fuzzy as you put it.
May I ask on what base is this prediction done if not on physical laws which are per se an expression of determinism.The fuzzyness or the randomness of the outcomes is the second part of this equation expressed statistically or as Hawking puts it "how likely each of these is".

Correct, but the subtlety is that the outcome is truly probabilistic: the universe doesn't 'know' what's going to happen until it does. It's not that particles have an unknown position, but rather that they don't have a position.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: One can express that duality of determinism and indeterminism in many philosophical forms but one can not deny their simultaneous coexistence in the most basical laws of nature.

Sure we can: determinism does not exist, insofar as quantum mechanics is concerned. You cannot determine the future with absolute accuracy because the fundamental rules that govern the behaviour of the universe and its contents are inherently probabilistic.

We can use mathematical formulae to describe probability distributions, but we still do not know the outcome of a trial until we run it.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: Here is another quotation from the same book ,the same chapter:
"We could still imagine that there is a set of laws that determines events completely for some supranatural being,who could observe the present state of the universe without disturbing it.However such models of the universe are not of much interest to us ordinary mortals.It seems better to employ the principle of economy known as Occam's razor and cut out all the features of the theory that cannot be observed.(unquote)

In his concise scientifical but also popular style Hawking cuts the limits of determinism and throughs the remainig features away to randomness.

In that case, I humbly disagree with Hawking's conclusion.

(January 10, 2009 at 2:07 pm)josef rosenkranz Wrote: That's,in other words, just the characteristics of statistical laws.
Let's take for instance a law which says :A+B =C, but where C has not a definite value but a statistical one of let's say 60%.
Now if we will repeat the experiment A+B for a 100 times we will get only in 60 cases the result C in at least 2 conditions:
- before each experiment we will not know if the result is exact C for the reason as put by Hawking ( in generally, not in the particular case of quantum mechanics)
-after achieving the value C in 60 experiments before the number of 100 the next results will be highly random.
Here we see the same dualty :the value C is predictable (say determined) for a certain number of experiments but is in the same time random for all the others.

Ah, no, that's not what 'determine' means. We can calculate the likelihood that a given outcome will occur, but we cannot determine whether it will actually occur or not (until we run the trial, of course).

We can say where an electron in a potential well is likely to be at some time t, but not where it will be. This is not because we don't have enough information, but rather the position of the electron is 'spread out' over all of space. Instead of it being at one particular place, it exists as a superposition of all possible positions. Until we measure it, whereafter things get complicated :p

Except your disagreement with Hawking's description on the limits of determinism by the Occam's razor principle, I'm sorry to say but I don't see any fundamental difference between our two positions.
What I call statistic you call probabilistic but they are essentially the same feature of physical laws because the very notion of "possibility"or "probability" does not implicate total indeterminism but leaves open a factor to be completed for the whole of the picture which
is just determinism.
Again, I took the uncertainity principle only as an example and I'm not going to contradict you on it's particulars which as one can see you know at a high degree.
I still affirm that most,if not all,laws of the universe and especially those concerning life are of a statistic (probabilistic) nature meaning the they
are subject to both deterministic and indeterministic features.
In my opinion one shall not oppose within a physical law determinism versus indetreminism but rather speak of a duality of them.

(January 12, 2009 at 1:28 pm)josef rosenkranz Wrote: What I call statistic you call probabilistic but they are essentially the same feature of physical laws because the very notion of "possibility"or "probability" does not implicate total indeterminism but leaves open a factor to be completed for the whole of the picture which
is just determinism.

Hmm, I disagree. We say that shuffling cards of flipping coins is 'random', but only insofar as we our brains can't keep up with the mechanics of what's happening: we could, potentially, model the coin classically and determine whether heads or tails will come up.
However, there is the added complication of quantum mechanics: there is a tiny (but non-zero) chance that the coin will do something quantum in the air, and the result will be different to what we classically expect.

This is what I mean by the universe being ultimately indeterminate. Macroscopic phenomena are deterministic only insofar as they have a very have probability of agreeing with the predictions of classical mechanics. When you get right down to it, there is an extraordinarily slim chance that, say, the underwear of that woman will 'pop' five feet to the left.

It is in this way that the universe is indeterminate: you cannot say with complete confidence what will happen to a given system at some arbitrary time in the future.

(January 12, 2009 at 1:28 pm)josef rosenkranz Wrote: I still affirm that most,if not all,laws of the universe and especially those concerning life are of a statistic (probabilistic) nature meaning the they
are subject to both deterministic and indeterministic features.
In my opinion one shall not oppose within a physical law determinism versus indetreminism but rather speak of a duality of them.

I'm not sure we're using the word 'determinism' and 'indeterminism' in the same way. When you say something has 'deterministic' features, what exactly do you mean?

(January 12, 2009 at 3:45 pm)DD_8630 Wrote:

(January 12, 2009 at 1:28 pm)josef rosenkranz Wrote: What I call statistic you call probabilistic but they are essentially the same feature of physical laws because the very notion of "possibility"or "probability" does not implicate total indeterminism but leaves open a factor to be completed for the whole of the picture which
is just determinism.

Hmm, I disagree. We say that shuffling cards of flipping coins is 'random', but only insofar as we our brains can't keep up with the mechanics of what's happening: we could, potentially, model the coin classically and determine whether heads or tails will come up.
However, there is the added complication of quantum mechanics: there is a tiny (but non-zero) chance that the coin will do something quantum in the air, and the result will be different to what we classically expect.

This is what I mean by the universe being ultimately indeterminate. Macroscopic phenomena are deterministic only insofar as they have a very have probability of agreeing with the predictions of classical mechanics. When you get right down to it, there is an extraordinarily slim chance that, say, the underwear of that woman will 'pop' five feet to the left.

It is in this way that the universe is indeterminate: you cannot say with complete confidence what will happen to a given system at some arbitrary time in the future.

(January 12, 2009 at 1:28 pm)josef rosenkranz Wrote: I still affirm that most,if not all,laws of the universe and especially those concerning life are of a statistic (probabilistic) nature meaning the they
are subject to both deterministic and indeterministic features.
In my opinion one shall not oppose within a physical law determinism versus indetreminism but rather speak of a duality of them.

I'm not sure we're using the word 'determinism' and 'indeterminism' in the same way. When you say something has 'deterministic' features, what exactly do you mean?

DD Hi
As you may have already noticed all the wrestlers have left the arena
for both of us alone.
May be that they have thought that the subject has burnt out and bears no further real interest.
But you asked me a new question and "obliged" me to answer.
Both, determinism and indeterminism have a lot of synonyme names with total or partial parallel meanings.
Indeterminism appears in a variety of names such as chaos,random ,chance,uncertainity,probability,
etc,,and determinism in such names as prediction ,order,etc,,
Now,where I write indeterministic or deterministic features I mean,generally speaking , one of the above notions,considering that for
each particular case one of them might be the most appropriate.
Here is an example of what I consider as the dual coexistence of both features, from the area of electricity, which is close to my understanding, being an electrical engineer.
Let's consider the most simple law of electricity namely the law of Ohm
and let's imagine the following experiment:we take a battery (as in our car of 12 volts) and connect in series a resistance of 1 ohm ,an ammeter and an on/off switch.
Before closing the switch the ammeter measures a value of current equal to 0.
After closing the switch the ammeter will measure exactly 12 amperes.
We can repeat the experiment for any times we want and we will get the same result. Right?..not exactly. The measured current depends on the accuracy of the measuring instrument so that the result is only partially predictable within practical conventional limits .
Let's imagine that we use an infinite accurate instrument (which exists only in theory but never in practice) and repeat the experiment.
Now, long before we arrive at the randomness of the results due to the uncertainity principle ,we will stumble on macro physical factors which will cause the randomness of the results due to the surrounding conditions where the experiment takes place such as temperature of the probe (resistance) ,humidity ,atmospheric pressure ,intensity of light,etc,,
From all these external conditions which affect the value of the measured current, the temperature is the most evident factor as being a random factor.
Remember the second principle of Thermodynamics which speaks about the increasing enthropy of the universe which means between others that the temperature of an object is intrinsecally random for being influenced by never calculable external energies of heat.
Now comig back to our experimenr we see thar within conventional limits the measured value of the current is predictable,i.e.deterministic and beyond these limits it becomes probabilistic with outcomes never
exactly predictable,i.e.indeterministic.
I will not argue with you if from a philosophic point of view you will correct my conclusion but in essence the duality of predictability and random as described in the experiment cannot be denied.

Hi all
I do not think man can change what the unknown future as in-store for our universe, or even life on earth.
But were the wasp that cannot reason will always follow the same pattern in its future, but man who can reason can and does change his future,mostly unknowingly, but others see were they are going and change direction.
Regards
Rex.