For the full story you need to read the article. I do not subscribe to "Bohmian Mechanics" since this theory is not constructed to be a substitute for a "real theory" of everything. It is very clear that BM is a "Stalking Horse" for an underlying theory that is the real goal of present day Physics. The problem with BM is the "particle"... a source of charge as it were. That is not a necessary part of any real theory and it needs correction. I suggest everyone read the "whole article" to be found in the issue above which is quite extensive and interesting with appropriate references.
This is not the only article that is useful but recently there is an article in Nature called
Quantum all the way:Nature :pp22-25 Published online 30 April 2008 | Nature | doi:10.1038/453022a
This pursues a similar subject in which a number of prominent experimentalists and some "doubting Thomas's"

agree that this quantum boundary is not as clear cut as once thought and indeed this boundary is becoming "blurred" in a way that suggests that there really is no boundary at all. I will take some short sections from this article to quote here...
QUOTE
Quantum all the way
Nature :pp22-25
Published online 30 April 2008 | Nature | doi:10.1038/453022a
How does our classical world emerge from the counterintuitive principles of quantum theory? Can we even be sure that the world doesn't 'go quantum' when no one is watching? Philip Ball talks to the theorists and experimentalists trying to find out.
[..]
Early quantum theorists treated the quantum-classical transition almost as a kind of sleight of hand, something that had to be imposed on quantum mechanics to recover the familiar world. Now, however, there are strong signs that the transition can be understood as something that emerges quite naturally and inevitably from quantum theory. If that's so, it implies that 'classicality' is at root simply another quantum phenomenon. "There's good reason to believe that we are just as much part of the quantum world as are the tiny atoms and electrons that sparked quantum theory in the first place,' says quantum theorist Maximilian Schlosshauer of the University of Melbourne in Australia.
Testing the new description of the quantum-classical transition involves experiments on systems ranging from photons to superconductors to microscopic vibrating beams. These efforts pose an extreme challenge to experimentalists, as they involve looking for very small effects on comparatively big things —rather like trying to detect the sag when a fly lands on San Francisco's Golden Gate Bridge. The effects very quickly get so small that many physicists believe it is absurd to try to see them. "One crowd says: 'Of course it will work —quantum mechanics says so'," says Schwab. "The other says: 'There's no way it will work —these guys are nuts'."
[..]
Thus one of the key questions in understanding the quantum-classical transition is what happens to the superpositions as you go up that atoms-to-apples scale? Exactly when and how does 'both/and' become 'either/or'?
Physicists have proposed many answers to that question over the decades. But the most failures one involves a phenomenon known as decoherence [3], which was identified and elucidated in the 1970s and 1980s. Crudely speaking, decoherence is a sort of leaking away of quantum behaviour when a particle interacts with its surroundings—for example, when an atom or molecule collides with those around or when light bounces off it. All we are left with is a partial picture of the system — a picture in which only a well-defined subset of macroscopic properties, such as position, are apparent.
[..]
In summary, decoherence offers a way "to understand classicality as emergent from within the quantum formalism', says Schlosshauer. Indeed, this picture means that the classical world no longer sits in opposition to quantum mechanics, but is demanded by it.
[...]
The decoherence description shows that there is no abrupt boundary, no critical size, at which quantum behaviour switches to classical. And that blurry boundary itself shifts depending on how it is measured. "It is the choice of the measuring apparatus that defines whether a specific object is quantum or classical,"(Good Elf's emphasis) says Anton Zeilinger of the University of Vienna. His team provided an example of this nine years ago, when it demonstrated quantum interference between beams of C60 fullerene molecules [8] — hardly as classical as the footballs they resemble, but nonetheless big molecules that can be seen with an electron microscope. Interference — the addition or cancellation of overlapping waves — is in this case a purely quantum effect, and can't be understood if the molecules are viewed as discrete particles. It is possible only if the molecules are in a superposition of states — in several places at once. "If you scan with a scanning tunnelling microscope a surface to which fullerene molecules stick, you see the little soccer balls sitting there as classical objects," says Zeilinger. "But if you choose our interference experiment set-up, they are quantum mechanically delocalized." In other words, he says: "The same object can behave as a quantum system in one situation, and as a classical system in another."
[..]
Bouwmeester hopes that it will soon be possible to test an alternative theory of the quantum-classical transition devised by Roger Penrose of the University of Oxford, UK. Penrose suggests that the 'collapse' of a superposition, rather than being a gradual affair resulting from environment-induced decoherence, is a rather abrupt event that is mediated by gravity. That is, it involves the emission of a graviton, the hypothetical fundamental quantum of the gravitational force, in much the same way that the decay of an excited molecule may happen via emission of a photon. He thinks that the cost in gravitational potential energy of keeping objects in a superposition becomes too great as objects get bigger, so that the objects 'go classical' on a definite timescale, which he estimates to be about a second or so for dust particles. Bouwmeester's mirror experiment should, if he can scale it up without losing sensitivity, be able to spot such a switch. "I am sceptical about this idea, but think it is worth testing,” he says.
Understanding quantum states has become much more than an intellectual curiosity, because handling quantum data may hold the key to the future of information technology
[..]
The decoherence description of the quantum-classical transition is not necessarily the end of the matter— it leaves unresolved some more fundamental questions about the interpretation of quantum theory (see page 39). But at present, it seems a fair bet that what we think of as the classical world is really only the quantum world viewed through the lens of decohered states. "The conceptual leap would then be to conclude from this that quantum mechanics is truly universal,' says Schlosshauer, "in the sense that everything, including us, is described by entangled quantum states "
I am hopeful that this is not "overuse" of a four page article in Nature but it is a very important issue that needs to be seen by those who are now having second thoughts about the "entire phenomenon".
The next point I would like to emphasize is the way in which quantum states (in the vein of Wheeler-Feynman Absorber Theory) are event specific and each quantum event or transaction is singularly attributable to individual transference of qubits. We know this is the case in quantum communication "links" which are actually transmission lines. The transmission line is a special case of a cavity. And cavity solutions are solutions of Schrodinger's or Dirac's wave Equations in "cavities" (which are just bounded systems). I would like to call attention to the fruitful manipulation of stimulated color centers in diamonds that are showing even at room temperature a single reception of a quantum process such as spin can be finely controlled to the extent that the phase accumulation of the state in resonance from illumination by a coherent source.
QUOTE (->
| QUOTE |
Quantum all the way Nature :pp22-25 Published online 30 April 2008 | Nature | doi:10.1038/453022a
How does our classical world emerge from the counterintuitive principles of quantum theory? Can we even be sure that the world doesn't 'go quantum' when no one is watching? Philip Ball talks to the theorists and experimentalists trying to find out. [..] Early quantum theorists treated the quantum-classical transition almost as a kind of sleight of hand, something that had to be imposed on quantum mechanics to recover the familiar world. Now, however, there are strong signs that the transition can be understood as something that emerges quite naturally and inevitably from quantum theory. If that's so, it implies that 'classicality' is at root simply another quantum phenomenon. "There's good reason to believe that we are just as much part of the quantum world as are the tiny atoms and electrons that sparked quantum theory in the first place,' says quantum theorist Maximilian Schlosshauer of the University of Melbourne in Australia. Testing the new description of the quantum-classical transition involves experiments on systems ranging from photons to superconductors to microscopic vibrating beams. These efforts pose an extreme challenge to experimentalists, as they involve looking for very small effects on comparatively big things —rather like trying to detect the sag when a fly lands on San Francisco's Golden Gate Bridge. The effects very quickly get so small that many physicists believe it is absurd to try to see them. "One crowd says: 'Of course it will work —quantum mechanics says so'," says Schwab. "The other says: 'There's no way it will work —these guys are nuts'." [..] Thus one of the key questions in understanding the quantum-classical transition is what happens to the superpositions as you go up that atoms-to-apples scale? Exactly when and how does 'both/and' become 'either/or'?
Physicists have proposed many answers to that question over the decades. But the most failures one involves a phenomenon known as decoherence [3], which was identified and elucidated in the 1970s and 1980s. Crudely speaking, decoherence is a sort of leaking away of quantum behaviour when a particle interacts with its surroundings—for example, when an atom or molecule collides with those around or when light bounces off it. All we are left with is a partial picture of the system — a picture in which only a well-defined subset of macroscopic properties, such as position, are apparent. [..] In summary, decoherence offers a way "to understand classicality as emergent from within the quantum formalism', says Schlosshauer. Indeed, this picture means that the classical world no longer sits in opposition to quantum mechanics, but is demanded by it. [...] The decoherence description shows that there is no abrupt boundary, no critical size, at which quantum behaviour switches to classical. And that blurry boundary itself shifts depending on how it is measured. "It is the choice of the measuring apparatus that defines whether a specific object is quantum or classical,"(Good Elf's emphasis) says Anton Zeilinger of the University of Vienna. His team provided an example of this nine years ago, when it demonstrated quantum interference between beams of C60 fullerene molecules [8] — hardly as classical as the footballs they resemble, but nonetheless big molecules that can be seen with an electron microscope. Interference — the addition or cancellation of overlapping waves — is in this case a purely quantum effect, and can't be understood if the molecules are viewed as discrete particles. It is possible only if the molecules are in a superposition of states — in several places at once. "If you scan with a scanning tunnelling microscope a surface to which fullerene molecules stick, you see the little soccer balls sitting there as classical objects," says Zeilinger. "But if you choose our interference experiment set-up, they are quantum mechanically delocalized." In other words, he says: "The same object can behave as a quantum system in one situation, and as a classical system in another." [..] Bouwmeester hopes that it will soon be possible to test an alternative theory of the quantum-classical transition devised by Roger Penrose of the University of Oxford, UK. Penrose suggests that the 'collapse' of a superposition, rather than being a gradual affair resulting from environment-induced decoherence, is a rather abrupt event that is mediated by gravity. That is, it involves the emission of a graviton, the hypothetical fundamental quantum of the gravitational force, in much the same way that the decay of an excited molecule may happen via emission of a photon. He thinks that the cost in gravitational potential energy of keeping objects in a superposition becomes too great as objects get bigger, so that the objects 'go classical' on a definite timescale, which he estimates to be about a second or so for dust particles. Bouwmeester's mirror experiment should, if he can scale it up without losing sensitivity, be able to spot such a switch. "I am sceptical about this idea, but think it is worth testing,” he says. Understanding quantum states has become much more than an intellectual curiosity, because handling quantum data may hold the key to the future of information technology [..] The decoherence description of the quantum-classical transition is not necessarily the end of the matter— it leaves unresolved some more fundamental questions about the interpretation of quantum theory (see page 39). But at present, it seems a fair bet that what we think of as the classical world is really only the quantum world viewed through the lens of decohered states. "The conceptual leap would then be to conclude from this that quantum mechanics is truly universal,' says Schlosshauer, "in the sense that everything, including us, is described by entangled quantum states " |
I am hopeful that this is not "overuse" of a four page article in Nature but it is a very important issue that needs to be seen by those who are now having second thoughts about the "entire phenomenon".
The next point I would like to emphasize is the way in which quantum states (in the vein of Wheeler-Feynman Absorber Theory) are event specific and each quantum event or transaction is singularly attributable to individual transference of qubits. We know this is the case in quantum communication "links" which are actually transmission lines. The transmission line is a special case of a cavity. And cavity solutions are solutions of Schrodinger's or Dirac's wave Equations in "cavities" (which are just bounded systems). I would like to call attention to the fruitful manipulation of stimulated color centers in diamonds that are showing even at room temperature a single reception of a quantum process such as spin can be finely controlled to the extent that the phase accumulation of the state in resonance from illumination by a coherent source.
Coherent Dynamics of a Single Spin Interacting with an Adjustable Spin BathR. Hanson,1*† V. V. Dobrovitski,2 A. E. Feiguin,1 O. Gywat,1 D. D. Awschalom1
Phase coherence is a fundamental concept in quantum mechanics. Understanding loss of coherence is paramount for future quantum information processing. We studied the coherent dynamics of a single central spin (a nitrogen vacancy center) coupled to a bath of spins (nitrogen impurities) in diamond. Our experiments show that both the internal interactions of the bath and the coupling between the central spin and the bath can be tuned in situ, allowing access to regimes with surprisingly different behavior. The observed dynamics are well explained by analytics and numerical simulations, leading to valuable insight into loss of coherence in spin systems. These measurements demonstrate that spins in diamond provide an excellent test bed for models and protocols in quantum information.
[..]
From a softpedia source...
California NanoSystems Institute at the University of California and US Department of Energy Ames Laboratory researchers believe they can answer these questions, or at least a part of them. According to the researchers, the key lies into understanding how the classical world, as we know it, emerges from the quantum level of matter. Unraveling the quantum dynamics of a single particle spin coupled to a collection of particles with random spins may unlock the way to understanding why some materials around us behave the way they do, such as the quantum tunneling process or magnetic resonance.
"We were stunned by these unexpected experimental results, and extremely excited by the ability to control and monitor single quantum states, especially at room temperature," said author of the study David Awschalom from the University of California. Quantum mechanical properties loss is now more important than ever into the field of quantum information, due to the overwhelming advantages opposed to classical computation techniques.
Most of the work is focused on high fidelity coherent control of a single spin, such as that of the experiment conducted by physicists in Awschalom who investigated the electron spin in a diamond, studying spin-bath interactions and decoherence dynamics. The diamond has unique features which enable scientists to investigate coherent dynamics and precise optical control of a single spin that can only be viewed in diamonds. The team observed multiple extraordinary phenomenons, amongst which time-dependent disappearance and reappearance or quantum oscillations inside the diamond lattice.
"To our surprise, when looking at longer times, the oscillations disappeared and then re-appeared," said co-author Ronald Hanson. The first time the phenomenon appeared, the team believed it to be a random artifact, but upon reseting the experiment a couple of time, the measurements convinced them that the oscillation pattern was genuine.
The result was using the complex arrangement of magnetic fields the transfer of spin quanta at room temperature is not only technically "perfect"... These oscillations , even when they had died away into the apparently "irretrievable quantum background", are states that are capable of revival for very long periods of time compared with the Rabi Frequency damping period. This is a "staggering notion" to be not only "entertained" by an intellectual mind but to actually find that quantum states "in the wild" are "individually" controllable as to the individual site in which they are able to be absorbed, reflected or "revived" through the manipulation of some nearby states in the "spin bath" that the single state is to be found immersed. This is more like the tuning of a wireless receiver than random Heisenberg Uncertainty. In these cases (which are admittedly very well chosen) there is no apparent "uncertainty" since the source and the sinks are "highly tuned to each other and "manipulable". So it is becoming quite "obvious that the quantum phase is far more important than what was once thought to be the case. It was all fine when our experiments were not so refined to test these cases in these extreme situations and the argument was brow beaten down to some of the older pundits such as Schrodinger and Einstein by Bohr. Nowadays it is possible to test this "interpretation" and it is found "wanting". This is a good thing and not a bad thing since it is possible to to get so much more out of refined states through resonance which are examples of Quantum Zeno Processes. This "interpretation" has a knock on influence in the rest of quantum physics as I have illustrated here through some relatively learned opinions seem to suggest.
I still disagree with much of these implications because of matters I have discussed in other threads. The interpretation of "moving photons" in space and the concepts of coherence in holographic systems indicate to me that we are dealing with a far more complex situation than we may first imagine. It is the result of 80 years of neglect by the Physics community and a certain "ploughing on" regardless attempting to ignore the "finer points" in favor of the short term "applications". The idea that quanta of all kinds are like little billiard balls moving around and bouncing off each other on a very uneven pool table is most probably quite wrong. The quanta them selves are not "random" or subject to "quantum noise" but the sources we have access to in the past are "poor" as coherent sources and as far as our maths have been able to determine with the lack of truly "good data" indicated that these processes were the outcome of so many "rolls of the dice"... removing the causality and the history of individual events from serious discussion for a very long time. Now with better instruments and with real data we might begin to understand that "quantum weirdness" is due to interpreting the underlying wave phenomena as particle phenomena. The result has been "quantum magic shows" where the public have been subjected to "sleight of hand" and called "fools" for trying to understand this "interpretation".
I can now speak with a little confidence about these issues. I hope everyone can now see where we are being led not by our philosophies but by our experiments (which should have been the case all along). The "in joke" for the last 80 years has been "quantum indeterminacy" and the indistinguishably of ensembles of quantum events on a manifold which is a seething Dirac Sea. All along it would appear to me at least that the spacetime continuum is smoother than a "quantum baby's bottom" and the smaller you go at higher and higher energies the smoother this manifold actually gets. There are thermal processes but their influence has been "grossly exaggerated" through the adoption of an unrealistic "model" of our reality... the particle reality... particle which are entirely "local" in nature and "indistinguishable" as to source. Of course if you want to adopt that approach we have a very good system of statistics to deal with it. It is "correct" as far as it goes... And we have gone about as far as it is possible to go down along that "yellow brick 'particle' road". It is time to adopt a wave theory of "matter" in which the "particle" is totally non-local, and this is 'entirely explained" by the former particle behave as waves ... more so at low energy than at high energy according to the de Broglie-Einstein Relationship. At the same time "quanta" are simply the movements of "packets" of energy between resonant states at the speed of light. In that process the photons that connect everything of real interest in our Universe "connect" by a "propagation" along a null geodesic in which distant "targets" connect and "entangle" instantly while the "capacity to do work" is usually confined to the speed of light and the "many paths" it may travel to the sink as a series of stationary phase accumulated states. The process is mitigated by advanced and retarded waves instantly emitted by the sinks and the sources "simultaneously" and then "worked through" over time and the resonant connection established. We know that entanglement is instantaneous and non-local. We know what we are apparently measuring is "resonance" and the "collapse of the quantum state through "decoherence". Clearly there is far more than this going on and it is a very complex issue but something that even a radio tech could understand.
I am reminder to say that the phase information around us in space as interferences is quasi-stationary due to the location of spatial matter waves. If you think this is so unimportant and that the simple inner product is sufficient for our purpose I would call your attention to this highly graphic example of two images in which the phase information of one image is mixed with the inner product "amplitude" of another.
Fourier transform theory: figure 6: The phase data dominates our perception.Clearly viewing this figure and the previous two images from which this composite information is taken we can immediately "grasp" that phase does matter... more that "size".

The next point to discuss is the way that the spatial Fourier domains of "collections of distributed sources" combine in ways that do not reflect a simple "ray theory of light".
Optical Fourier Processor - note that this is not a "ray" modelIf not "rays" then photons are "something else and quite apart". The explanation is in a liberal wave interpretation of the phenomenon of gauge invariance of the propagating photon through stationary states... or at least "piecemeal" stationary states. We never really understand the nature of photons through the outcomes of the collapse of the state in "decoherence". No photon is observed without severely "restricting" this intermediate state. In the Wheeler-Feynman Absorber context the "events" are singular source to sink and the quanta is preserved in "ideal transmission" for single photons. Of course not every photon is transferred ideally but that is another matter regarding the ability in experiments to identify the "true source" and matching "true sink" of each and every single quantum event. Interference experiments strongly suggest that a single photon "explores" the entire "cavity" before choosing it's destination. This exploration is the "many paths" or "many histories" of the raylike photons in so many interpretative theories. The experiments above indicate that the quantum realm is not one in which we can chop and choose the paradigm in each and every case to "hide" the underlying principle. One principle must fit all. The single quantum state can in principle be prepared to receive a single event using conventional high technology.
There is a reciprocal connection in nature of time and frequency and space and reciprocal space that cohabit in our Universe (both spatially and temporally). This is not "grasped" by a particle interpretation of "trajectories"... it is more relevant through a spreading (or converging) wave interpretation of phenomena (especially in the phenomenon of "light" which so dominates our experience). We also know this "pictorial particle view" is going to have difficulties with those many paths and with the issue of "time symmetry". Five minutes of thinking about that one and I am sure we can all see the advantage of the wave approach.
I could say more about this problem but that is a little more "on course" than what I was saying just previously. It is also difficult for me to confine the discussion to "just one thing" because our Universe is such an "emergent phenomena". I sure hope this discussion has not made things "worse" than they already were.
Cheers
dawn
16th May 2008 - 10:24 PM
Good Elf, contributers,
(Good Elf)
QUOTE
Sorry... I have left a pretty scattered trail behind me regarding this subject.
Good Elf, I just felt I needed to explain why I did not respond a few post back, I just (please blame it on me) did not understand what concept/idea you wanted to convey. It seems that you have clarified your position in which when time allows would like to respond after
mr_homm because of
respect for you both.
Thank you for the time you spent, I am sure it will be interesting.
dawn
Good Elf
16th May 2008 - 11:34 PM
Hi
dawn, mr_homm, Ivars, bukh et al,
QUOTE
I just (please blame it on me) did not understand what concept/idea you wanted to convey.
No... not at all... entirely my fault. I am sure there are better ways to say all this. I hope you both forgive me for babbling on. As to actually clarifying the position it is actually scary to think of everything I would have liked to say...
I know I have promised you to do a few things and I never really get around to it.
Cheers
Ivars
17th May 2008 - 06:19 AM
hi mr. homm, dawn
Thanks for bringing rigged Hilbert space to this thread.
I read about rigged Hilbert spaces and they nicely extrapolate in to the need of possibility of having a disconnected infinitedimensional ( with many levels of infinities) space which as such would not sustain Newtons first law since translation in such space is impossible, and correspondingly mass as inertia does not exist.
The connection to infinitesdimensional rigged Hilbert space which is, as far as i can understand, connected or multiply connected, is via ALL the space of the probability density function(s) which will characterize the distribution present in chaotic infinite dimensional spaces , so they will carry an deterministic influence on what goes on in Gelfand tripple spaces, while itself being 100% probabilistic.
I wonder it entropy of such infinitesimal chaotic space ( having infinitesimal CHAOTIC spacetime dimensions, most likely characterized by irrational numbers) would be negative. If so , the problem with complexity and 2nd law of TD will also disappear.
The only problem will remain with mathematics which does not explain today how phase transitions between different infinitesimal scales and spaces is possible due to lack of mathematics of operations, or rather , hyperoperations in today's language. But that is solvable if physical model will be clear enough to require certain properties of such math ( like speed fast enough to change types of numbers of some subsets of existing number types into others, or even , new types). Work is going on in this direction, but difficulties to compute such fast functions has also delayed analytical development- so far.
I do not see it as a big problem, though.
bukh
17th May 2008 - 09:53 AM
Good Elf
QUOTE: ""It is the choice of the measuring apparatus that defines whether a specific object is quantum or classical"
Or put differently - am I right in supposing, that provided the measuring apparatus is choosen with a sufficiently "high" sensitivity - then ANY object IS quantic.
It is back to the good question - is continuous part of physical - or should continuous (and infinite) be reserved for pre-physical states - as potentials out from which physical can be "born"
And this also will have bearings to the very concept of a wave -
Can a wave be continuous - is it possible to have a dynamic - a change - without discreteness - and yes I know I have been asking that question (too) many times - anyhow

As long as there exist no definition of particle - it is meaningless - or at best difficult to discuss quantum vs. continuous.
Intuitively I would say that particle is intimately connected with repetition - without repetition it is not possible to interfere AND translate (transmit) a Physical "signal)
And intuitively I would say that physical involve a "Space" - physical cannot be based upon points
And intuitively I would say that mathematics and physics IS the same - just expressing themselves differently - physical can best be defined as everything which can be percepted by human physical senses - senses in the scale of human flesh and blood - and quantum behavior in this scale is measured or percepted as fairly big oscillations - no possibility to see the underlying oscillations, whereas mathematics is a mind perception - not bound to our physical senses - but in as much that mathematical and physical is the same - mathematics cannot be based upon points - because it is not possible to construct a space out from points. Perhaps it is a much too simplistic way of thinking - but mathematical points - any math number must therefore have a corresponding space aquainted.
So a wave - irrespective how we look at a wave and irrespective how small the wave may be - which scale it is looked at - then a wave is expressed out from discrete spacious "particles".
Good Elf
18th May 2008 - 10:17 AM
Hi
bukh, dawn, mr_homm, Ivars et al,
QUOTE (bukh+)
QUOTE (Quantum all the way: Nature 30 April 2008+)
""It is the choice of the measuring apparatus that defines whether a specific object is quantum or classical"
Or put differently - am I right in supposing, that provided the measuring apparatus is choosen with a sufficiently "high" sensitivity - then ANY object IS quantic.
It is a "great sound byte" but it is to be understood with "extreme" caution. The instrument itself "should" not determine if a process is a quantum or is not yet an instrument is the way in which we can "sense" and interpret the measurements we are making in the Universe. "We" humans are not good recording instruments and we are not able to directly interpret these phenomena that we neither see or measure directly... they are beyond our sensory perception so they are open to question and interpret. This is where a mathematician can show how this new information fits with existing data. The mathematician can't make a result in an instrument prove his or her theory but a mathematician can show that the new data is able to be incorporated smoothly into existing theory (or not).
There is a difference between "measurements" and "observables". Two different scientific instruments will make measurements of a single observable (obviously not the one and same measurement or observable "simultaneously"... that's "impossible"). Everything being "equal"... and things are not equal in this World... These measurements will not necessarily measure the one and the same "value" (the numbers will be different). For instance the charge on an electron may be determined by two or more differently instruments (working on slightly different physical principles and interpretations of the "underlying quantities"... for instance the torsion coefficient of a quartz fiber or a quantity of mass in an oil droplet.. which are constructed to determine this quantity of "charge". There is usually no "individual dial or screen" on which this determination can be "explicitly" displayed, a number of separate determinations or readings will be required to determine this "one value" of electronic charge. There are several stages in this process and the values are sometimes inter-related through this process of the measurement itself. A careful calculation of errors must be a part of the process in order to convince the review process that the methodology is "right".
You can construct a one-off instrument but it will not necessarily "show" the parameter you wish to view because it is a complex inter-related technical piece of equipment. Systems are constructed that are not "absolute instruments" measuring quantities that are independent of laboratory and sample states and dependent only on the physical constants. The instrument must usually be individually calibrated to provide "scales" and "values" when compared with some "standard" that may not exist in a particular laboratory. A lot of "black art" is required in which the "right answer" is determined using quite reasonable assumptions about how that instrument behaves under that circumstance. The "right answer" quite often insists on it agreeing with some classically derived result and with the results derived from other laboratories. A "wrong answer" is one that might simply need instrument calibration or even redesign to improve the precision or accuracy (which are different). There may be undiscovered systematic errors as well.
There is also a desire to fulfill the parameters of the funding board. Experiments are not easy to describe when the funding board requires you to virtually know the answer to the problem you are trying to solve before you ask for the funding. Ontologically this is the wrong "question". There are going to be "right" and "wrong" answers. A "wrong" answer will not be allowed to be published since it is reviewed by a group of 'eminent persons" who are able to sanction the result or refuse the result based on their "expert opinion". Unpublished papers gain no kudos. That is all for "starters"... Here is an extract from a Philosophical Dictionary about "ontology"...
QUOTE (philosophical ontology+)
Derived from the Greek word for being, but a 17th-century coinage for the branch of metaphysics that concerns itself with what exists. Apart from the ontological argument itself there have existed many a priori arguments that the world must contain things of one kind or another: simple things, unextended things, eternal substances, necessary beings, and so on. Such arguments often depend upon some version of the principle of sufficient reason. Kant is the greatest opponent of the view that unaided reason can tell us in detail what kinds of thing must exist, and therefore do exist. In the 20th century, Heidegger is often thought of primarily as an ontologist. Quine's principle of ontological commitment is that to be is to be the value of a bound variable, a principle not telling us what things exist, but how to determine what things a theory claims to exist. These are the things the variables range over in a properly regimented formal presentation of the theory. Philosophers characteristically charge each other with reifying things improperly, and in the history of philosophy every kind of thing will at one time or another have been thought to be the fictitious result of an ontological mistake.
IMHO Science is not "immune" to ontological errors. Ontological errors can lead to the problems we are making right now in the assertions we are all making regarding the theory of "particles". This "unaided reason" is flawed as is all human activity. We must ground our ideas in reason that we can test.

Metaphorically speaking.. I don't trust you to make a theory that I will accept on your assertion alone and you will not accept a theory that I simply put up here that I think is "philosophically sound". To do so is very "foolish"... You would be accepting ideas that are "unsound" and this would allow you to be manipulated by my ideas and visa versa. Many people are such individuals and you can get people in high rank and authority that are completely bound to baseless acceptance of "authorities".
That is why I must be "forced" to present independent experiment that is based not on the musings of philosophers but on the trials and questions placed directly before the Universe (herself) to answer. Like the Oracle of Delphi these question we place must be properly contrived to seek the underlying Truth and not the outcomes our ego's wish for... not an easy task. We are vain creatures and subject to vices of all kinds. Like the Oracle's Answers the "purity of your heart" is a deciding ingredient in the mix that will produce the seeker's individual prophecy, you will receive only what your heart truly seeks.
The final scene from "Indiana Jones and the Last Crusade" indicates the choices we all make in life in an allegorical way. Many choose a "poisoned chalice" rather than the Truth because we prefer the attractive resolution to our questions rather than some unpalatable fact that we do not want to fit into our "Cosmos".

Which one do you want to be .... Indiana Jones or Walter Donovan who had sold out to the Nazis and accepted "poor" advice from Dr. Schneider :?

... he h