Quantum Reality and Normal Everyday Speech: Why?
Posted 04 April 2013 - 04:46 PM
For all practical purposes, I do not possess the knowledge of physics or mathematics which allows me a direct understanding of quantum mechanics/physics and what it reveals to us about subatomic and cosmological realities and events.
Many of you have shared descriptions, analogies, metaphors, and models with me which have given me a little bit of insight into these quantum realities. I am very appreciative of the understandings you have given me.
However, I have come to accept that these descriptions which use normal (non-mathematical) everyday speech do not provide a clear, complete, nor functional understanding of these realities which are described through the use of quantum physics and the mathematics quantum physics utilizes. To quote one of us who has taught me a great deal, “There's absolutely no way you can get anything beyond a conceptual hint about these phenomena without being fully engaged in the mathematics.” To use a metaphor he provided me, non-mathematical everyday metaphors can no more provide an accurate or useable understanding of the subatomic and cosmological realities quantum physics and its associate mathematics provides, than a baking-soda-volcano-model can provide an accurate and useable understanding of actual volcanoes.
Having come to accept this level of limitation, allows me to articulate the question I have long wanted to ask here, as regards quantum realities in particular but other matters of physics as well.
In this particular CloudyNights forum, i.e. Science! Astronomy & Space Exploration, and Others, normal (non-mathematical) everyday speech is used to talk about quantum phenomena. If normal (non-mathematical) everyday speech cannot provide an understanding of quantum realities beyond-providing-conceptual-hints, then why do we engage in this type of normal (non-mathematical) everyday speech about quantum realities in the manner we here?
Don’t get me wrong. I am not speaking prescriptively. I am asking a descriptive question, because I am fascinated by philosophical anthropology. I am very interested in why people, like us, do the things we do. Concerning dialogue about quantum realities, I want to understand why we do what we are doing here. Specifically, Why do we speak about quantum realities in normal speech here on this site if we acknowledge that such speech doesn’t say much beyond-providing-conceptual-hints of what quantum realities really are?
Why do you think we do this, here?
Posted 05 April 2013 - 06:12 AM
Posted 05 April 2013 - 10:21 AM
The best illustration of this comes from statistical mechanics, the underpinning of thermodynamics. When Boltzmann put forward this idea, he was ridiculed. He took his own life in despair. Today we use his ideas with the same ease as measuring a length of 2x4.
I don't really want to enter into a lengthy discussion of it. There was, and is, no great divide between older and newer ideas of the physical world. They build up as a whole, and the whole is not yet finished.
Posted 05 April 2013 - 11:25 AM
Your post seems to indicate that the poor conceptions we non-physicists have of quantum stuff is due to poor writing and limited understandings by those who write the popularized stuff.
In your opinion, can the quantum stuff be described in normal everyday (non-mathematical) speech in ways which are conceptually accurate and get at the substance of quantum understandings of the way-things-are at the subatomic levels? or no?
Posted 05 April 2013 - 12:44 PM
As an analogy (and analogies are what we tend to use in normal speech when math skills fail us), think about weather forecasting.
Meteorology is also a highly mathematical field, one that requires massive number crunching, high levels of uncertainty, understanding of statistics and probability, sensitive dependence on initial conditions (chaos), and a very specific terminology.
Very, very few of us understand it in any depth. Yet we talk about it regularly, there's a popular television channel devoted to it, and we all seem to be comfortable talking about cold fronts, storm systems, low pressure, cyclones, jet streams, and the like. We have an intuition of what we might expect in a few days when looking at a satellite photo. But we have zilch in the way of mathematical understanding of it.
What we've done is simply leap the implementation details and assume them as a given. We work at a higher level of abstraction. The forecasting process, with its mathematical theory, is a black box to us -- we know what comes out of it, but we simply trust that those results are valid. We don't need to know the deep math or the inner workings of the theories, we just deal with the higher-level objects that derive from them.
I think its the same for us when we discuss things like relativity or quantum mechanics here. We don't understand how all these effects are derived, we just know that the math is there, and that there ARE people that understand it, and we accept the black-box results that come out of it. Then we manipulate those results in our own world. Danny has a point, that if you can't trust those who are supposed to understand the theory, then you need to be a bit suspicious of that black box. I don't think the situation is as dire as he does, though, although you definitely have to be cautious when reading popular materials from second-hand sources.
But we here don't need to know how to derive time dilation or relativistic foreshortening. We just need to know that it happens, and then figure out how to apply it. We don't need to understand the math behind the scattering of photons, but we can see the results in the diffraction disks of our telescopes.
So I think, Otto, that you're right about the difficulty in trying to talk about concepts that most of us simply can't comprehend. But we CAN, I think, understand the human-scale results that flow out of those black boxes, and that's what I think we tend to focus on here, with occasional tentative pokes at the boxes themselves.
Posted 05 April 2013 - 12:46 PM
* One can never know everything about a particular object with absolute certainty.
* Althoough an object may be said to occupy one location, there is some probability that it is somewhere else
* Everything has the property of particles and waves,
* If an experiment is designed to validate whether an object is a particle or wave packet, the conclusion will be "Yes, it is" (IIRC "Schrodinger's Cat" Paradox is an example of this).
* An object that lacks the energy to penetrate a barrier can still do so.
To me the interesting thing about this is the two quirky things about the mathematics behind quantum mechanics.
First, quantum mechanics is associated with the field of complex numbers. These are of the form
a + b*i where i = SQRT(-1).
Ordinary, or real numbers are one-dimensional, we talk about a number line or real line, but complex numbers are two dimensional. Modern mathematicians define a complex number as an order pair of real numbers (a,b) with addition and multipication between (a,b) and (c,d) defined as
(a,b) + (c,d) = (a+c,b+d)
(a,b) * (c,d) = (ac-bd,ad+bc)
If b = d = 0, then this turns in to regular aritmetic so (a,0) and (c,0) are actually other forms for real numbers a and c. Also, define i = (0,1) giving
i^2 = (0,1)*(0,1) = (0-1,0+0)= (-1,0) = -1
The thing about this is that this shows the 2 dimensional nature of complex numbers, which make them, well, unreal. The fact that these complex numbers get into electric circuit computations and flowstream calculations doesn't make them all that much easier to get acquainted with....
The second thing is that the math behind quantum mechanics involves mathematical objects that do not commute when you multiply them. Two objects A and B commute under multipication if AB = BA or AB - BA = 0. Real numbers and even complex numbers commute but lots of mathematical objects do not. These include matrices which you may have worked with in high school. In fact, quantum mechanics is based on the algebra of matrices and the objects that they represent, linear transforms or operators. An axiom in quantum mechanics is that if two operators A and B are canonical conjugates, that is, have the dimension of energy * time when multiplied, do not commute but instead their commutator [A,B] is
[A,B] = AB - BA = i*h*I
where I is the identity operator, equivalent to 1 in ordinary arithmetic. Heisenberg's uncertainty principle is a special case of this.....
Every so often I wonder if it's the nutty properties of complex number and non commuting objects that make quantum mechanics hard to explain in plain English.
Posted 05 April 2013 - 01:07 PM
Posted 05 April 2013 - 01:13 PM
.. these are completely explained in terms of spacetime geometry. In the Dirac equation for the electron, the "i" has a geometric meaning - the volume element in spacetime. When one approximates to get successively the Pauli equation then the Schroedinger equation, the only trace left of this geometric entity, is the lone "i" in momentum operator. So it's the Cheshire cat grin of spacetime geometry as expressed in the "Dirac matrices" that enter into the equation for fermions (electrons, neutrinos, etc.)
The really strange and hard to understand behavior of QM comes in the form of the statistical behavior of identical particles. An assemblage of photons is fundamentally different than one of electrons, and neither is like one of baseballs. This points, not to a problem with QM, but with the description of the world in terms of individual material points swimming in an otherwise empty background of spacetime. Until this idea (going back to Democritus) has been superseded, no resolution of the apparent paradoxes of QM will be forthcoming. It is almost certain that a new conception of both spacetime AND matter and their relation is needed. The current concept is exhausted of descriptive power.
Posted 05 April 2013 - 01:46 PM
It is very difficult to provide analogies for quantum weirdness, the math works but it doesn't apply to our realm of experience, but most people don't get the math, I certainly don't. But I do know that trying to explain half spin to a layman is almost impossible, there is no concept in our everyday lives that can tie it to. Without the math, or a deeper understanding of the concepts, we are forced to try and use woefully inadequate and whacky analogies, like a cat that is both dead and alive at the same time because we haven't looked at it.
Posted 05 April 2013 - 05:21 PM
I understand that light is created when an electron falls from a higher orbit/level around an atom to a lower orbit/level around the given atom.
I understand that the electron, when it drops from one level to another, does not pass through the space between the two levels from the higher level to the lower level.
I understand that the transition from the one level to the other is instantaneous.
Now, how accurate are these descriptions? Or, are these descriptions just incorrect? Or are these descriptions the light-electron equivalent of a baking-soda-volcano?
Posted 05 April 2013 - 05:57 PM
The forecasting process, with its mathematical theory, is a black box to us -- we know what comes out of it, but we simply trust that those results are valid.
You might! I don't, especially after getting caught in an hurricane on Spruce Knob, WV at the AHSP. The forecast was partly cloudy.
PS: Hurricanes are no fun on a mountain top.
Posted 05 April 2013 - 06:37 PM
And that analogy, as we know, was proposed in a letter to Einstein by Schroedinger in order to share his objection to some implications of QM. I rather doubt that Schroedinger ever intended the analogy to become so popular. He knew (in fact, of course, helped create), and Einstein knew, the math.
And it isn't a useful analogy anyway because it mixes two completely different realms that aren't in the least commensurate.
Posted 07 April 2013 - 02:58 PM
was written by Cecil Adams - in verse - in the Chicago Reader, a free weekly
Cecil, you're my final hope
Of finding out the true Straight Dope
For I have been reading of Schroedinger's cat
But none of my cats are at all like that.
This unusual animal (so it is said)
Is simultaneously live and dead!
What I don't understand is just why he
Can't be one or other, unquestionably.
My future now hangs in between eigenstates.
In one I'm enlightened, the other I ain't.
If you understand, Cecil, then show me the way
And rescue my psyche from quantum decay.
But if this queer thing has perplexed even you,
Then I will and won't see you in Schroedinger's zoo.
— Randy F., Chicago
Schroedinger, Erwin! Professor of physics!
Wrote daring equations! Confounded his critics!
(Not bad, eh? Don't worry. This part of the verse
Starts off pretty good, but it gets a lot worse.)
Win saw that the theory that Newton'd invented
By Einstein's discov'ries had been badly dented.
What now? wailed his colleagues. Said Erwin, "Don't panic,
No grease monkey I, but a quantum mechanic.
Consider electrons. Now, these teeny articles
Are sometimes like waves, and then sometimes like particles.
If that's not confusing, the nuclear dance
Of electrons and suchlike is governed by chance!
No sweat, though — my theory permits us to judge
Where some of 'em is and the rest of 'em was."
Not everyone bought this. It threatened to wreck
The comforting linkage of cause and effect.
E'en Einstein had doubts, and so Schroedinger tried
To tell him what quantum mechanics implied.
Said Win to Al, "Brother, suppose we've a cat,
And inside a tube we have put that cat at —
Along with a solitaire deck and some Fritos,
A bottle of Night Train, a couple mosquitoes
(Or something else rhyming) and, oh, if you got 'em,
One vial prussic acid, one decaying ottom
Or atom — whatever — but when it emits,
A trigger device blasts the vial into bits
Which snuffs our poor kitty. The odds of this crime
Are 50 to 50 per hour each time.
The cylinder's sealed. The hour's passed away. Is
Our cat still purring — or pushing up daisies?
Now, you'd say the cat either lives or it don't
But quantum mechanics is stubborn and won't.
Statistically speaking, the cat (goes the joke),
Is half a cat breathing and half a cat croaked.
To some this may seem a ridiculous split,
But quantum mechanics must answer, "Tough *BLEEP*.
We may not know much, but one thing's fo' sho':
There's things in the cosmos that we cannot know.
Shine light on electrons — you'll cause them to swerve.
The act of observing disturbs the observed —
Which ruins your test. But then if there's no testing
To see if a particle's moving or resting
Why try to conjecture? Pure useless endeavor!
We know probability — certainty, never.'
The effect of this notion? I very much fear
'Twill make doubtful all things that were formerly clear.
Till soon the cat doctors will say in reports,
"We've just flipped a coin and we've learned he's a corpse."'
So saith Herr Erwin. Quoth Albert, "You're nuts.
God doesn't play dice with the universe, putz.
I'll prove it!" he said, and the Lord knows he tried —
In vain — until fin'ly he more or less died.
Win spoke at the funeral: "Listen, dear friends,
Sweet Al was my buddy. I must make amends.
Though he doubted my theory, I'll say of this saint:
Ten-to-one he's in heaven — but five bucks says he ain't."
— Cecil Adams
Posted 07 April 2013 - 08:36 PM
Posted 08 April 2013 - 07:07 AM
Posted 08 April 2013 - 10:17 AM
Or for that matter, anything specialized that requires a lot of study, to someone who hasn't done the studying.
Posted 08 April 2013 - 04:02 PM
So, the question in my mind is, what are the reasons experts in oenology, musicology, and painting speak/discourse/dialogue in amateur settings? and are these the same reasons experts in physics and mathematics speak/discourse on issues of QM in a setting such as this?
Posted 08 April 2013 - 07:00 PM
Posted 08 April 2013 - 08:03 PM
You and I, Otto, are spectators; All we can do is try to learn something from the discussion.
Posted 08 April 2013 - 09:11 PM
Also, the amateurs they are talking to generally understand what they're saying. Guys like Jarad, Illanitedave, and deSitter are the target audience.
You and I, Otto, are spectators; All we can do is try to learn something from the discussion.
There's really no difference between us.
Posted 08 April 2013 - 10:05 PM