Posted on 04/02/2009 7:05:41 PM PDT by GodGunsGuts
What a beautiful illustration of my point, dearest sister in Christ! And also E = MC2. Thank you ever so much for sharing your outstanding insights!
I am sure you find all this very interesting, but what has it to do with anything on FP?
FP?
What a fascinating observation, dearest sister in Christ! Of course it could (if the "if" condition is satisfied); the Shannon model is truly universal.
Thank you ever so much for this outstanding and highly informative essay/post!
I was not. An observation is an event. It's an interaction event. A, or Ψ, represents the physical entity itself, not how it behaves in some event. You are attempting to observe Ψ itself, which is equivalent to attempting to equate event to essence.
"Observation itself forces a change from probability to a state.
An observation is an interaction, an event. The essence of A doesn't change. It is still represented by Ψ. You are attempting to equate a nonexistent fundamental change of essence with the particle's behavior during and prior to an event. That can not be done. Ψ*ξΨ, is a linear operator operating on the "square of the complex amplitudes". It's a function that gives the probability function that indicates the particle will behave, or give a certain measure ξ. An experiment is an event that gives a particular measure ξ. Naturally the calculated function will not be equivalent to an experimental result. Repeated runs will indicate the functional form of the range of results is correct.
"Hence A(observed) equals fixed state is different from A(unobserved) equals probability fuction with the potential to resolve to both A(observed) state or another state.
A can not be used in both instances here to construct a logical statement, since a function is not equivalent to a particular value in the range of that function. If A is used for the function, Ai, or some other symbol should be used to represent a particular value. Keep in mind that in no way does either represent the essence of the physical entity itself. A indicates the possible "behavior", or state of the entity. Ai is simply a state, or displayed behavior, which does not change A, so that no other Ai in the range becomes an impossible state subsequent to any event.
"please explain why observing one slit of the two slit experiment destroys the interference pattern and results in a particle like pattern. There is a Noble Prize in it for you.
In order to calculate the observable in an event such as the double slit, the Ψs must be added, then squared. The interference comes from the sum of the Ψs. If the experiment is run single slit, there is no sum in the calculation and no interference.
==If we look at the example of sperm meeting egg, we see a creation of new information, without a mental process involved. And on that small scale, anyway, we see that Mr. Gitt’s assertion is incorrect.
Unless said mental process is already coded in the information contained in the sperm and the egg.
==But information under the Shannon model is the reduction of uncertainty (Shannon entropy) in the receiver as it moves from a before state to an after state. It is the action of successful communication, not the message itself.
Trying to get my brain around what you are talking about. Could you give me some real world examples of reduction of uncertainty, and the before and after state?
All the best—GGG
No. I did no such thing in #153.
"As it happens, of course, it is quite possible to "prove a negative" in many cases. For example, if one says "X cannot exist," one can approach the proof by assuming that X does exist, and showing that such an assumption leads to a contradiction.
Proofs are only good in math. They can't be used in science to say something about reality unless evidence supports it, and in that case there's no proof, only the support of evidence. Only evidence counts in science, or in the application of math to reality. So one can never prove something does not exist, anymore than someone could prove something does exist. All that can count is evidence.
In the outline you gave, in order for it to be applied to reality, one must first believe reality itself is logical. That belief depends on the evidence and can not be proved. It is a fundamental and necessary belief, w/o which no rational grasp of reality can be achieved. Nevertheless, any mathematical proof applied to reality is not a proof of reality, because it fundamentally relies on evidence.
I am NOT talking about running the experiment "single slit." I'm (and Feynman is) talking about running the experiment with TWO slits, both with electrons going through them, with an electron detector at one or both slits. The detector observes when an electron passes through, but does not affect the electron in any other way. In that case, the interference pattern disappears.
Maybe I'm not saying it well. Here's a goofy video that nonetheless shows what I mean: http://search.yahoo.com/search?ei=UTF-8&fr=yfp-t-105&p=the+feynman+double+slit+experiment&rs=0&fr2=rs-bottom
And this gets to an even more esoteric point: http://www.universeofpower.com/understanding_your_power/quantum_physics/the_wave-particle_duality_of_quanta.html The money paragraph:
"What if we record the detector results, but erase the data before we look at the results? The result: The interference pattern is observed, and the electrons behaved as waves. But notice that in this scenario, the experiment is complete in every respect when we decide to erase the recorded slit data. Up until that moment, there is absolutely no difference in this test and the one run earlier, which produced particle clumping when we looked at the slit data. But we obtained different results. It seems that by removing the slit data completely, after the fact, it has actually changed the outcome of the already completed experiment."
It's not a physical change in the setup that changes whether or not the interference pattern shows up. Two slits are present. Two detectors are present. What determines if the interference pattern shows up is whether or not the data is erased.
Sounds nuts, huh? Here's a paper on a related actual experiment: http://hal.archives-ouvertes.fr/docs/00/11/03/92/PDF/halsubmission.pdf
The choice to measure or not after the photon goes through the "slits" (here a beam splitter) affects whether or not an interference pattern shows up and hence how the photon acted at the beam splitter -- as a particle or as a wave. Hence, an after-the-fact choice to observe or not changed the behavior of the particle/wave at BSinput.
So you see, I am not talking about one slit, or even changing the slits and the equipment at the slits. The act of observing itself changes the physical reality as reflected by the appearance or non-appearance of the interference pattern.
For even more strangeness, take a look at some of the stuff on quantum encryption. Way beyond the scope here, but fun (if it doesn't make your head explode like it nearly did mine).
OK, I'm done with this topic. Was fun.
That's interference, not noise. Interference is not a form of noise. Noise is represented by a random function of the underlying interaction variables, such that they effect all processes equally. Interference is not. Interference represents particular interactions of those variables, which are themselves subject to noise.
Without the underlying uncertainty inherent in all interactions, essentially no interactions would occur. That underlying uncertainty is what gives rise to the Gaussian distribution of events known as noise and makes interaction events possible.
The phone rings. You don't know who is calling or what they are going to say. You pick up the phone and listen to the words. Your uncertainty is reduced. Whatever the caller said to you that reduced your uncertainty is measurable in bits.
My computer is going to send a message to your computer over the internet. Your computer doesn't know a message is coming; it is uncertain. The message has a long way to go, there will be other traffic in the channel as other computers are also communicating. And there will be thermal noise along the way.
To make sure you get this message right, my computer will encode it before it sends it. Your computer speaks the same language and will decode it on the other end. That way it'll "know" what is noise so it can ignore it.
And because of all the traffic on the internet, it'll also use a packet or address to make sure it gets to you and not be broadcast to every computer on the internet (autonomous communication.) When your computer finally gets the message decoded, it is no longer uncertain. The message it received is measured in bits.
I am your television set, you tune me into FoxNews but I am uncertain what will happen next. FoxNews is fixing to air the Special Report. It encodes the program so that all the receivers (it is a broadcast message) can decode the program to get rid of the noise. As the signals come to me, your receiver, I decode them. My uncertainty is reduced and I display the message (program) that I receive which can also be measured in bits.
I am a bird fixing to fly away. My wing muscles are relaxed in a state of uncertainty. I biologically signal my wings to rise up and down. The muscles are no longer uncertain.
At the level of the molecular machinery of the muscle in the wing - the reduction of uncertainty was in the transition from having hydrolyzed an ATP to having changed configuration (actomyosin.) And I paid the thermodynamic tab for that shift from before state to after state by dissipating heat in the local environment. That is also measurable in bits.
So you're saying two things then.
First, you apparenty acknowledge that it is sometimes possible to prove a negative -- which I already knew, having once taken an abstract linear algebra class, the upshot of which being that a certain mathematical construct did not exist.
Second, if "proofs are only good in math," then your response about "can't prove a negative" is quite pointless.
And third ... if you are going to differentiate between reality and things like math and logic, you have clearly not been paying attention to the world around you.
Placing a detector at one, or both slits causes the analysis to depend on Ψ and not ΣΨi at both slits. Regardless of all the handwaiving and mystical pronunciations of spookiness, superimposed cats, and data erasures causing time warpage of events. The analysis is as I have posted and the results are according to that. Feynman's analysis in the various cases is the same.
"So you're saying two things then.
No, that's one statement.
"First, you apparenty acknowledge that it is sometimes possible to prove a negative -- which I already knew, having once taken an abstract linear algebra class, the upshot of which being that a certain mathematical construct did not exist.
Proofs are only good in math.
"Second, if "proofs are only good in math," then your response about "can't prove a negative" is quite pointless."
The subject regarded elements of reality, not math. No one can prove any particular conjured up thing does not exist, anymore than they can prove something does exist.
"And third ... if you are going to differentiate between reality and things like math and logic, you have clearly not been paying attention to the world around you."
Ridiculous!
Yes -- but to say that "proofs are only good in math," is to say many other things as well.
Proofs are only good in math.
Ah, yes. I take it you're claiming that (say) logic and math are equivalent disciplines, then? Put another way -- what do you mean by "math," in your statement? Is arithmetic equivalent to algebraic topology in that conception? Or are you perhaps suggesting that precision would offer no useful distinctions?
The subject regarded elements of reality, not math.
And are you really saying that there is no such thing as "physical proof?" For example, it is not "proof" of my claim that a pebble is under a certain cup, to lift up the cup to show the pebble's presence? Of course it is proof.
And are you really saying that math has no connection with reality? Are you really making such a claim?
No one can prove any particular conjured up thing does not exist, anymore than they can prove something does exist.
And thus, the pebble under the cup, even if I see and touch it, has not been "proved" to exist under the cup?
Suppose I state a negative proposition, "there is no pebble under the cup." I can prove that negative proposition, in a "real" situation, by simply lifting the cup to see if there is in fact no pebble there. (And the proposition is obviously falsifiable by the same means.)
Ridiculous!
Hey -- if your comments can't stand up to logical scrutiny, it's a bit of sour grapes to blame the logic, rather than your comment.
Yes. All you have is evidence, not proof. Proof is restricted to math.
"what do you mean by "math," in your statement?"
Math is any logical construction regarding rational relationships of representations. The only reality to math is that it exists only as a mental construct. As such, it is dependent on the physical machinery of mind to exist.
"...are you really saying that math has no connection with reality? Are you really making such a claim?"
Any application of math to reality depends on the existence of evidence that the application is indeed valid.
"thus, the pebble under the cup, even if I see and touch it, has not been "proved" to exist under the cup?"
That's correct. The senses have only determined evidence. The evidence is fact, not proof.
"Suppose I state a negative proposition, "there is no pebble under the cup." I can prove that negative proposition, in a "real" situation, by simply lifting the cup to see if there is in fact no pebble there."
You can only make a true atatement once hte evidence has been uncovered. The true statement can not be made before the cup's lifted.
You talk in circles. I’m through.
Rubbish!
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