'Zeno effect' verified—atoms won't move while you watch

October 23, 2015 by Bill Steele, Cornell University
Graduate students Airlia Shaffer, Yogesh Patil and Harry Cheung work in the Ultracold Lab of Mukund Vengalattore, assistant professor of physics.

One of the oddest predictions of quantum theory – that a system can't change while you're watching it – has been confirmed in an experiment by Cornell physicists. Their work opens the door to a fundamentally new method to control and manipulate the quantum states of atoms and could lead to new kinds of sensors.

The experiments were performed in the Utracold Lab of Mukund Vengalattore, assistant professor of physics, who has established Cornell's first program to study the physics of materials cooled to temperatures as low as .000000001 degree above absolute zero. The work is described in the Oct. 2 issue of the journal Physical Review Letters

Graduate students Yogesh Patil and Srivatsan K. Chakram created and cooled a gas of about a billion Rubidium atoms inside a vacuum chamber and suspended the mass between laser beams. In that state the atoms arrange in an orderly lattice just as they would in a crystalline solid.,But at such low temperatures, the atoms can "tunnel" from place to place in the lattice. The famous Heisenberg uncertainty principle says that the position and velocity of a particle interact. Temperature is a measure of a particle's motion. Under extreme cold velocity is almost zero, so there is a lot of flexibility in position; when you observe them, atoms are as likely to be in one place in the lattice as another.

The researchers demonstrated that they were able to suppress quantum tunneling merely by observing the atoms. This so-called "Quantum Zeno effect", named for a Greek philosopher, derives from a proposal in 1977 by E. C. George Sudarshan and Baidyanath Misra at the University of Texas, Austin,, who pointed out that the weird nature of quantum measurements allows, in principle, for a to be "frozen" by repeated measurements.

Previous experiments have demonstrated the Zeno Effect with the "spins" of subatomic particles. "This is the first observation of the Quantum Zeno effect by real space measurement of atomic motion," Vengalattore said. "Also, due to the high degree of control we've been able to demonstrate in our experiments, we can gradually 'tune' the manner in which we observe these atoms. Using this tuning, we've also been able to demonstrate an effect called 'emergent classicality' in this quantum system." Quantum effects fade, and atoms begin to behave as expected under classical physics.

The researchers observed the atoms under a microscope by illuminating them with a separate imaging laser. A light microscope can't see individual atoms, but the imaging laser causes them to fluoresce, and the microscope captured the flashes of light. When the imaging laser was off, or turned on only dimly, the atoms tunneled freely. But as the imaging beam was made brighter and measurements made more frequently, the tunneling reduced dramatically.

"This gives us an unprecedented tool to control a quantum system, perhaps even atom by atom," said Patil, lead author of the paper. Atoms in this state are extremely sensitive to outside forces,l he noted, so this work could lead to the development of new kinds of sensors.

The experiments were made possible by the group's invention of a novel imaging technique that made it possible to observe ultracold while leaving them in the same quantum state. "It took a lot of dedication from these students and it has been amazing to see these experiments be so successful," Vengalattore said. "We now have the unique ability to control quantum dynamics purely by observation."

The popular press has drawn a parallel of this work with the "weeping angels" depicted in the Dr. Who television series – alien creatures who look like statues and can't move as long as you're looking at them. There may be some sense to that. In the quantum world, the folk wisdom really is true: "A watched pot never boils."

Explore further: A little light interaction leaves quantum physicists beaming

More information: Y. S. Patil et al. Measurement-Induced Localization of an Ultracold Lattice Gas, Physical Review Letters (2015). DOI: 10.1103/PhysRevLett.115.140402

Y. S. Patil et al. Nondestructive imaging of an ultracold lattice gas, Physical Review A (2014). DOI: 10.1103/PhysRevA.90.033422

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docile
Oct 23, 2015
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Protoplasmix
3 / 5 (2) Oct 23, 2015
Can it be said that an increasing frequency of measurements becomes analogous to a bound state?
jackjump
1.8 / 5 (5) Oct 23, 2015
So the universe we know is just a bunch of quantum particles that some thing/force/deity is watching?
docile
Oct 23, 2015
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docile
Oct 23, 2015
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kulashaker
5 / 5 (2) Oct 23, 2015
Isn't nature wonderful?
docile
Oct 23, 2015
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docile
Oct 23, 2015
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docile
Oct 23, 2015
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antigoracle
3.7 / 5 (3) Oct 23, 2015
Isn't nature wonderful?

She's an enchanting vision, who lets us watch and even touch, but yet keep us lusting for her secrets.
docile
Oct 23, 2015
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dan42day
4.2 / 5 (5) Oct 23, 2015
As far I know, we have never found an answer that hasn't begged another question. Such is the way of a world held up by turtles.
Protoplasmix
5 / 5 (4) Oct 23, 2015
Because once the secret is found, the scientists lose their job.
Einstein lost his job in 1905? And again in 1916?
Jayded
not rated yet Oct 23, 2015
Only from this the human consciousness could affect the result by manipulation of these data, which were already stored in fixed form.


Or were they stored in a fixed form?
docile
Oct 24, 2015
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Protoplasmix
4.5 / 5 (8) Oct 24, 2015
In 1905/1916 the scientific community did run very differently, in many aspects in opposite way. For example the most insightful people were mathematicians ["during" ?] this time, breakthrough findings were done with young physicists, now they're done with elderly chaps and so on.

Zeph, I think you can study the maths without the physics, but not the physics without the maths. And the graduate students pictured above don't appear too elderly. If there's any veracity to your critique that success leads to unemployment, it's less than evident here.
docile
Oct 24, 2015
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docile
Oct 24, 2015
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docile
Oct 24, 2015
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docile
Oct 24, 2015
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Bigbangcon
2 / 5 (8) Oct 24, 2015
This is an attempt to create sensation and to incorporate spiritualism and idealism in quantum dynamics! There was an article couple of years ago, even in the mother of all journals, namely Nature; which claimed that consciousness could erase data stored in computer memory or something like this; but no one heard anything about it after that sensational publication.

This feat (described here) is highly doubtful that they could stop quantum tunnelling as a kinetic motion and other motions like vibrational, rotational and electronic motion by any means, least of all through observation. Quantum dynamics (uncertainty principle) and dialectics forbids such a feat. For dialectics, "There can be no matter without motion and no motion without matter"!
cracker_mon
1 / 5 (3) Oct 24, 2015
Isn't it possible that the quantum tunneling effect is only present when some one is actually thinking about the effect and believing that it is happening?
SuperThunder
1 / 5 (5) Oct 24, 2015
atoms won't move while you watch

I mean, I guess, in the same way a photograph steals your soul.

I chained this leopard down with a laser powered force field, I guess leopards can't pounce me when being observed. My mind be a magical vortex of conscious-might!
Bigbangcon
2.6 / 5 (5) Oct 24, 2015
Here is a reference to the discussion of the Nature article mentioned in my comment above: http://www.quantu...ropy.php
docile
Oct 24, 2015
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docile
Oct 24, 2015
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Bongstar420
5 / 5 (1) Oct 24, 2015
I don't believe you can determine the quantum tunneling rate by not observing something

Thats asinine

BTW..when you soot photons at something, you do more than "observe" it. You could realize the same outcome without observing anything. You simply run the test and don't look at the data.

Or are these people not obfuscating what an "observation" is and creating confusion between and "observation" and a conscious agent?
docile
Oct 24, 2015
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TheGhostofOtto1923
3.4 / 5 (5) Oct 24, 2015
Is it just the imaging imaging laser that causing the atom to jump into an excited state so that the atom can later fluoresce.
Coupla questions:

What if we're looking at it with instruments which are unable to resolve it completely? IOW what resolution is necessary to create the effect?

What if we are looking at it with no instruments at all, but are only aware that the actual thing exists and we know it is in our frame of view?

Would the effect work with Cylons as well? Not the old model but the new one? Or maybe the old model too - I dont know.
TheGhostofOtto1923
3.9 / 5 (7) Oct 24, 2015
This is an attempt to create sensation and to incorporate spiritualism and idealism in quantum dynamics
Naw this is entirely evidence-based. Faith is belief despite evidence. Faith abhors evidence it cant conjure up for itself.
Noumenon
3.7 / 5 (6) Oct 24, 2015
Is it a consciousness thing that affects the atoms?


The 'act of observation' somehow effects the quantum system being observed…

It's not that consciousness 'reaches out' and physically alters the quantum state,…. but is rather that consciousness acts to impose a filter on the state, selecting only the component that is compatible with our conscious capacity to synthesize experience and so 'observe'. The 'filter' here is our a-priori conceptual structure for which we evolved to order experience at the macroscopic scale. This conceptual-filter is an artificial one when the quantum realm is made to conform to it. Our intellectual faculties are getting in their own way.....

Noumenon
3.7 / 5 (6) Oct 24, 2015
....And no, it does not matter, that experimental apparatus is used to 'do the observing', … because that apparatus was already made compatible with our 'filter', .....being designed, operated, and results interpreted at the macroscopic scale.
TheGhostofOtto1923
3.4 / 5 (5) Oct 24, 2015
consciousness acts to impose a filter on the state, selecting only the component that is compatible with our conscious capacity to synthesize experience and so 'observe'. The 'filter' here is our a-priori conceptual structure for which we evolved to order experience at the macroscopic scale. This conceptual-filter is an artificial one when the quantum realm is made to conform to it. Our intellectual faculties are getting in their own way...
-Except for that one little problem you always fail to acknowledge... consciousness is an illusion. A philo-generated conspiracy to keep 'things which can never be resolved' (like the soul) active.

We will emulate 'consciousness' artificially. This is an inevitability. Not difficult as it is an entirely electromechanical thing.

Machines are already conscious as they respond to you and adjust their behavior accordingly. So do animals.

Can a schnauser collapse the waveform?
https://en.wikipe...xplained
Returners
1.4 / 5 (9) Oct 24, 2015
One of the oddest predictions of quantum theory – that a system can't change while you're watching it – has been confirmed in an experiment by Cornell physicists


Stop, just stop.

You people should:

1, Lay off the Crack Cocaine
2, Turn in whatever fraudulent degrees you claim to have.
3, Go watch a football game and then come back and read what you wrote.

Nothing ever changes huh.

Now we've heard it all here boys.

These idiots wrote a paper, and claimed stuff can't change while you're watching it.

Please, somebody fire everyone on this team, and any students who didn't call their professors "idiots" should get expelled too.
Noumenon
3.4 / 5 (5) Oct 24, 2015
Except for that one little problem you always fail to acknowledge... consciousness is an illusion


You referenced Dennett, who's opinion is light-years away from being a consensus, and whom avoids 'Chalmers hard problem', by virtue of denying the most immediate observation possible,… self-awareness and personal experience,… by only willing to address the third-person external observation-of-consciousness.

In any case, your point is not important wrt my posts above…. as I agree that the brain is the physical basis of the mind, and that there is no 'other entity' to be taken as being consciousness,…. it is an emergent epiphenomenon that arises on account of the laws of nature.

However, the mind is not a Passive physical entity like the brain, but rather is Active in synthesizing experience, with it's own a-priori faculties for processing experience, that are not themselves laws-of-nature. It's why I used the word 'artificial'.

Noumenon
5 / 5 (3) Oct 24, 2015
We will emulate 'consciousness' artificially.

Our brains are physical things, so, yes I agree, it is reasonable to suppose that the epiphenomenon of consciousness could in principal be Created with an alternative physical basis.

However, you would agree that such an achievement is not possible without first an understanding of how self-awareness is emergent from the physical brain?

The difference between emulating a phenomenon, and creating the physical basis for which that phenomenon is emergent,.... is the difference between a computer-dork living in his mom's basement,... and a scientific understanding of the phenomenon in question.

Noumenon
5 / 5 (3) Oct 24, 2015

Machines are already conscious as they respond to you and adjust their behavior accordingly


Only from a third-person perspective, which is the premise of Dennett's weak vacuous argument. This 'Turing test' quality of understanding consciousness, only amounts to fooling an observer, ….as a charlatan would,…. not an actual understanding of anything.

Searle's Chinese Room Argument, render's the Turing test resoundingly pointless, in terms of an actual understanding of how consciousness emerges from the brain.
Noumenon
5 / 5 (3) Oct 24, 2015
Is consciousness interfering to produce the Quantum Zeno effect?


If consciousness arises on account of quantum effects, as in the Penrose-Hameroff 'Orchestrated objective reduction' model, decoherence would need to be suppressed long enough, in some way, perhaps through a Zeno-effect.
SkyLy
2 / 5 (4) Oct 24, 2015
What does this mean, is the light on or off when i close the fridge ?
docile
Oct 24, 2015
This comment has been removed by a moderator.
jimbo92107
1 / 5 (2) Oct 25, 2015
So ian atom-sized tree in the woods not only will not make a sound, but won't even fall unless it has an audience? Little prima donna!

Does it happen if you shoot the atom with a laser, but are somewhere else on vacation? Is it really an indecisive atom-sized cat?
my2cts
2 / 5 (4) Oct 25, 2015
but is rather that consciousness acts to impose a filter on the state,

Quantum mechanics has in common with consciousness is that we understand neither one. Otherwise I do not see the connection with this experiment.
my2cts
2 / 5 (4) Oct 25, 2015
"The famous Heisenberg uncertainty principle says that the position and velocity of a particle interact."
"Interaction" in physics means that there is a force between two objects or systems, that is, an exchange of momentum and energy. I don't see how position and velocity of a particle can do that.
my2cts
1.8 / 5 (5) Oct 25, 2015
Tunneling can occur only as long as the atoms are indistinguishable. When the laser is switched on more and more atoms fluoresce and so lose their indistinguishable nature and can no longer tunnel.

As to why indistinguishable particles end up in a BE condensate, that is the part of the fascinating mystery of QM. We do not yet understand.
Noumenon
4 / 5 (4) Oct 25, 2015
Quantum mechanics has in common with consciousness is that we understand neither one. Otherwise I do not see the connection with this experiment.


[considering standard theory.....]

We have great predictive knowledge of quantum systems. What we don't have, is an intuitive-understanding of quantum mechanics. This is a clue to the connection between mind and quantum systems....

On account of the connection, there is a distinction between raw 'quantum interaction' and 'observation (by mind).

If it weren't for this connection QM would be purely deterministic as formulated by the Schrodinger (Dirac) equation, but instead, upon an observation(mind), there is a fundamental incompatibility between the evolution of the state-vector and the state-reduction (collapse) upon an observation(mind).....

Noumenon
4 / 5 (4) Oct 25, 2015
.... Decoherence, which takes place and is accounted for in the deterministic Schrodinger equation, does not result in 'collapse of the wavefunction' to a particular [conceptual] value. What decoherence does do, is to reduce a superposition-of-states to a statistical-mixture-of-states,.... the difference being that the former allows for interference effects while the latter does not. IOW, decoherence does not explain why we observe(mind) only one of the possible results rather than a fuzzy mixture of possibilities. In any case, in an experiment, if there is loss of interference terms, ... if decoherence occurs with the experimental apparatus,.... then a QM experiment is not being performed, but rather simply a classical one.....
Noumenon
4 / 5 (4) Oct 25, 2015
.... Another connection is implicit in the standard von Neumann Hilbert space formulation of QM, in that the basis representation (the 'coordinate frame' in which the state-vector is defined and mathematically evolves) is dependent upon possible observable values, and therefore the macoscopic experimental arrangement.

This macoscopic experiment arrangement must be compatible with our intuitive conceptual framework, despite that QM itself is not intuitive. Why the break down? To me this implies that our intuitive conceptual structure that we evolved with is an artificial layer..... that the conceptually formless underlying quantum reality, is forced through this 'conceptual-filter' to conform to our a-priori conceptual framework implicit in the design, operation, and interpretation, of the macroscopic experimental equipment. This is the wavefunction collapse,... distinct from simply quantum-interaction.

Btw, a single particle can tunnel through a potentially well.
Noumenon
4 / 5 (4) Oct 25, 2015
The difference between a Realist point of view (which is repeatedly experimentally refuted or must escape via proposing metaphysics) and a Positivist point of view,...is that the later understand that our mind dependent intrinsic layer or 'conceptual-filter', precludes us from ever knowing Reality directly as it exists in itself,.... but only 'as experienced' by mind. That's the connection.

It is a bit more subtle than the typical misapprehension that consciousness (as a etherial entity) 'reaches out' and modifies reality directly.
Noumenon
4 / 5 (4) Oct 25, 2015
Tunneling can occur only as long as the atoms are indistinguishable. When the laser is switched on more and more atoms fluoresce and so lose their indistinguishable nature and can no longer tunnel.

As to why indistinguishable particles end up in a BE condensate, that is the part of the fascinating mystery of QM. We do not yet understand.


Quantum tunneling occurs with fermions also, that require Fermi-Dirac statistics as opposed to Bose-Einstein statistics,.... and for single particles in a potential well, as noted above.
Noumenon
4 / 5 (4) Oct 25, 2015
but is rather that consciousness acts to impose a filter on the state,

Quantum mechanics has in common with consciousness is that we understand neither one. Otherwise I do not see the connection with this experiment.


What is perhaps missing is an 'algebra of propositions' that would be representational of our hard-wired conceptual framework, that could interface with standard theory. Positivism,... (the realization that we have reached the limits of possible intuitive understanding),.... does just fine though. It is not idealism either. There must be an objective reality that "says no" [d'Espagnat] to arbitrary theories.
my2cts
1 / 5 (3) Oct 25, 2015
Quantum mechanics has in common with consciousness is that we understand neither one. Otherwise I do not see the connection with this experiment.


[considering standard theory.....]

We have great predictive knowledge of quantum systems. What we don't have, is an intuitive-understanding of quantum mechanics. This is a clue to the connection between mind and quantum systems....

On account of the connection, there is a distinction between raw 'quantum interaction' and 'observation (by mind).

If it weren't for this connection QM would be purely deterministic as formulated by the Schrodinger (Dirac) equation, but instead, ...

Everything observed is in full agreement with the Schrodinger equation. Observation does not involve the mind.
Noumenon
4 / 5 (4) Oct 25, 2015
Everything observed is in full agreement with the Schrodinger equation.

The Schrodinger equation does not allow for the collapse of the wavefunction** to particular conceptual value,.. so therefore is itself incompatible with the experimental result of only one result of many possibilities obtained.

IOW, the Born-rule of the statistical interpretation of the [square] wavefunction, is an additional [interpretational] layer to the Schrodinger equation itself. This is what I mean by the deterministic evolution of the state-vector being incompatible with the state-vector reduction. Of course the Schrodinger(Dirac) equation works to give a probability distribution.

**apart from objective-collapse non-standard theories which must include an additional term to accomplish this,... or metaphysical interpretations that avoid the collapse.

Observation does not involve the mind.

It is a truism. Decoherence does not explain singular outcomes.
my2cts
2 / 5 (4) Oct 25, 2015
Everything observed is in full agreement with the Schrodinger equation.

... so therefore [the Schrodinger equation] is itself incompatible with the experimental result ...

W R O N G. If it were correct, which it is't, then QM would have been proven to be wrong, which it obviously is not.
Observation does not involve the mind.

It is a truism.

In physics it is. On phys.org apparently it is not, since the involvement of the mind is discussed above.
Decoherence does not explain singular outcomes.

All we have is the probability interpretation. Google for L.E. Ballentine.
The rest is a mystery.
Noumenon
4 / 5 (4) Oct 25, 2015
You stated above that no one understands QM,... I take this to mean in the sense in which Feynman meant likewise,... that 'no one has an intuitive understanding of QM'.

But if as you say, "everything observed is in full agreement with the Schrodinger equation" which is deterministic, shouldn't we then have an [intuitive] understanding? That we don't in fact must then be attributable to an artificial layer of concepts imposed by the mind.

How else would you reconcile your two statements?
Noumenon
4 / 5 (4) Oct 25, 2015
so therefore [the Schrodinger equation] is itself incompatible with the experimental result of only one result of many possibilities obtained.


W R O N G. If it were correct, which it is't, then QM would have been proven to be wrong, which it obviously is not.


I explained what I meant in the next paragraph. That the deterministic evolution of the state-vector via the Schrodinger equation is incompatible with the state-vector reduction into a single outcome obserbed in experiment, is not something that is refuted by anyone accepting standard QM.

It is a fact that the wavefunction does not collapse into a single prediced value via the Schrodinger equation [unless that equation is modified with extra terms as in non-standard objective collapse theories]. Your objection rests on a misunderstanding of my posts.
my2cts
2 / 5 (4) Oct 25, 2015
We understand how to use QM. QM is also in full compliance with SR. The only interpretation free of paradoxes is the one proposed by L.E. Ballentine (http://www-dft.ts...ne.pdf).
We do not, for example, understand how a plane wave representing light causes a single atom among many to make a transition and absorb it. We only know the probability that this occurs.
That the deterministic evolution of the state-vector via the Schrodinger equation is incompatible with the state-vector reduction into a single outcome obserbed in experiment, is not something that is refuted by anyone accepting standard QM.

The solution is obvious: reject state-vector reduction. Why? I don't need it (thanks, Leslie), but I do need the Schrodinger equation.
my2cts
2 / 5 (4) Oct 25, 2015
You can go a step further by including the measurement apparatus (MA) in the state. The MA has a number of different mutually orthogonal states. Each is coupled to a very large phase space so that for example a photon is absorbed and not reemitted. Each of these states is by design coupled to a component of the wave function describing a possible outcome of the system to be measured. Thus the so-called state vector collapse is not a dynamic collapse but is a consequence of the design of the experiment.
Protoplasmix
not rated yet Oct 25, 2015
...we can gradually 'tune' the manner in which we observe these atoms. Using this tuning, we've also been able to demonstrate an effect called 'emergent classicality' in this quantum system." Quantum effects fade, and atoms begin to behave as expected under classical physics.
The same effect is encountered in the double-slit experiment as the frequency of observing which slit is used increases.
Noumenon
4 / 5 (4) Oct 25, 2015
That the deterministic evolution of the state-vector via the Schrodinger equation is incompatible with the state-vector reduction into a single outcome obserbed in experiment, is not something that is refuted by anyone accepting standard QM.

The solution is obvious: reject state-vector reduction. Why? I don't need it (thanks, Leslie), but I do need the Schrodinger equation.

Yes, the Copenhagen Interpretation is not the only one, but seems the one with the least 'interpretational desperation' and is most in line with standard quantum mechanics as formulated by von Neumann and results of actual experiments.

my2cts
2 / 5 (4) Oct 25, 2015

Yes, the Copenhagen Interpretation is not the only one, but seems the one with the least 'interpretational desperation' and is most in line with standard quantum mechanics as formulated by von Neumann and results of actual experiments.


The one that is paradox free is the Ballentine one. It's been a while since I read his paper in RevModPhys, but check it out or his book.
Noumenon
4 / 5 (4) Oct 25, 2015
I will. Your link above is broken, but I will find it, thanks.

I'm not familiar with Ballentine, so will have to investigate further, ... but someone posted this at PhysicsForums,...

"What is structurally non-standard, and perhaps erroneous, is Ballentine's apparent rejection of the projection postulate mentioned in the above textbooks without replacing it with something effectively equivalent, in his discussion of filtering measurements as a means of state preparation".

The 'projection postulate' is what I called 'state-reduction' above in von Neumanns formulation. As already pointed out, my comments were only in reference only to standard QM.

Noumenon
3 / 5 (4) Oct 25, 2015
,.... and since the Schrodinger equation by itself (without the additional Born rule layer, or extra terms, or metaphysics) does not result in collapse (despite only one observable resulting in actual experiment),.... does Ballertine modify that equation or postulate a metaphysical rug under which to sweep the rest of the wavefunction?
my2cts
2 / 5 (4) Oct 25, 2015
Ballentine restricts himself to stating that the wave function describes the probability of a measurement result. No modifications.
my2cts
2 / 5 (4) Oct 25, 2015
Here is a link to the RMP paper: http://www.psiqua...ne70.pdf .
This is essential reading.
Noumenon
4 / 5 (4) Oct 25, 2015
Ballentine restricts himself to stating that the wave function describes the probability of a measurement result. No modifications.


Isn't that what the Born rule in the Copenhagen interpretation, already does as an additional interpretational step?,.... which is to say, the Schrodinger equation can not do that by itself.
TheGhostofOtto1923
3.7 / 5 (6) Oct 25, 2015
Only from a third-person perspective, which is the premise of Dennett's weak vacuous argument
No sir. The machine responds accordingly whether there is ever anyone to acknowkedge it or not.
This 'Turing test' quality of understanding consciousness
The Turing test only deals with human-like 'consciousness' - whether a human can be fooled by a machine or not.

Human 'consciousness' necessarily includes compulsions for self-preservation and reproduction, things that machines don't need to bother with.

Our sense of self is determined primarily by these 2 factors. 'I need to survive so that I can reproduce.'

No philo has ever demonstrated whether our 'irreducible complexity' arises from this fundamental root.

The need for a soul or 'consciousness' follow.
my2cts
2 / 5 (4) Oct 25, 2015
,.... and since the Schrodinger equation by itself (without the additional Born rule layer, or extra terms, or metaphysics) does not result in collapse (despite only one observable resulting in actual experiment),.... does Ballertine modify that equation or postulate a metaphysical rug under which to sweep the rest of the wavefunction?

I will have to write an article on this someday. Everything follows from classical field theory.
Ballentine does not alter any of the physics, it is purely an interpretation.
TheGhostofOtto1923
3.9 / 5 (7) Oct 25, 2015
No philo has ever demonstrated whether our 'irreducible complexity' arises from this fundamental root
No of course not. They never do scientific experiments. They wait for scientists to do their experiments, which are designed to answer scientific questions, and then scavenge the data for something philosophically relevant to say.

Good thing no one ever listens to them anymore. As it is, it will take generations to clean up the mess theyve made.
SuperThunder
1 / 5 (3) Oct 25, 2015
Kant was the only philosopher with a criteria for falsification, and Einstein falsified it... with Relativity!

Also, the human mind does not define what the human mind observes in the universe. The universe came first, and delusion is mostly selected out of the human species (until civilization built the Great Moon-Howler Zoo), since nature kills stuff. So many carts being pushed down the street by invisible horses.
Noumenon
4 / 5 (4) Oct 25, 2015
Kant was the only philosopher with a criteria for falsification, and Einstein falsified it... with Relativity

Since above I referred to our a-priori conceptual structure as an artificial-synthesis of reality, it should be clear that I don't agree with Kant in synthetic a-priori knowledge that must necessarily correspond to experience. He was wrong in not realizing the possibility of predictive knowledge without intuitive understanding (QM, and elements of GR).

Wrt, non-Euclidean geometry as used in GR; the Riemannian manifold in the limit of tangent space, a local reference frame of an observers experience, reduces to Euclidean geometry (actually Minkowskian).

I believe he was correct wrt his transcendental deduction, just wrong in its implications for synthetic a-priori knowledge.

Noumenon
4.2 / 5 (5) Oct 25, 2015
Also, the human mind does not define what the human mind observes in the universe. The universe came first.


This is a rather patently absurd statement. The mind most definitely has an effect on what the mind can experience. Simply a truism.

"There is no way to remove the observer us from our perception of the world, which is created through our sensory processing and through the way we think and reason. Our perception and the observations upon which our theories are based are shaped by a kind of lens, the interpretive structure of our human brains." - Stephen Hawking

"The doctrine that the world is made up of objects whose existence is independent of human consciousness [mind] turns out to be in conflict with quantum mechanics and with facts established by experiment" - B. d'Espagnat

DonGateley
not rated yet Oct 26, 2015
Cool!

Sorry, I couldn't help myself. :-)
docile
Oct 26, 2015
This comment has been removed by a moderator.
antialias_physorg
4.3 / 5 (6) Oct 26, 2015
The universe came first, and delusion is mostly selected out of the human species (until civilization built the Great Moon-Howler Zoo), since nature kills stuff.

Nature kills stuff that isn't useful - not necessarily stuff that isn't true. E.g. it's pretty useful for us to believe in solid matter (even though it's 99.999% empty space), or that 'love conquers everything' (even though love doesn't stand a chance in the face of an onrushing asteroid or simply old age/death).
There are delusions which are selected for, rather than against. One such delusion _might_ be free will. It _might_ be crucial to believe that free will exists in order for our brains to function (e.g. to avoid depression).

The brain is an evolved organ beneficial to survival of the species. Just like lungs or a spleen. It's not a universal truth-discerning-machine. We may wish to use it as such, but we should keep in mind the history (i.e. biases) that come with an evolved organ.
Noumenon
4.3 / 5 (6) Oct 26, 2015
d'Espagnat http://www.temple...espagnat for promotion of catholic ideology in science.

I'm an atheist and could care less about his personal beliefs. His religious beliefs do not negate his career in physics. He has a long distinguished career writing about the conceptual foundations of quantum mechanics. See his classic books on the subject, ....no religion in them.

Shouldn't you be praying at the 'water surface'?

Of course the Universe developed and it existed before and independently of human mind, even according to Christian mythology itself.

Who says otherwise?
docile
Oct 26, 2015
This comment has been removed by a moderator.
Noumenon
4.2 / 5 (5) Oct 26, 2015
The universe came first. ...This is a rather patently absurd statement...
You should more think and oppose less...;-)


You should oppose less by not deliberately editing comment exchanges.

Universe existed before human mind ... Who says otherwise?

versus

Why should I care about ones religious views?
Noumenon
4.2 / 5 (5) Oct 26, 2015
Kant was the only philosopher with a criteria for falsification, and Einstein falsified it... with Relativity


To elaborate on this a bit from above.....

I believe Kant was correct wrt his transcendental deduction, with a slight revision in light of modern science investigation of scales not commensurate with that in which the mind evolved, as follows ,....that our a-priori intellectual faculties determine the form of possible experience and so the conditions for the [intuitive] understanding. We have great predictive knowledge in QM and GR, but not (as Feynman concurred) an [intuitive] understanding.

.....
Noumenon
4.2 / 5 (5) Oct 26, 2015
....

Wrt synthetic a-priori knowledge disproved by the use of non-Euclidean geometry for GR.....

I don't think that argument is entirely fair, ....albeit legitimate and often repeated. The fifth postulate was already suspect way before Kant's time, so it's hard to believe he would hinge his core epistemology on that postulate. I believe what is important wrt his point are the elements of geometry as conditions for experience to be possible, time and space,... and not constructions with those elements.

Since, as I mentioned above, in the limit of an observers local experience (reference frame carrying the clock and rod), ....in the tangent space of the Riemann manifold, the geometrical construction reduces to Euclidean (though it is hyperbolic because time is treated with space). So implicit within Einstein's own mathematical formulation, are Kant's conditions for experience....
Noumenon
4.2 / 5 (5) Oct 26, 2015
... Einstein made an operational definition of time and space by transposing that intuition as a stated definition to BE a physical system. This is despite that there has never been an ontological physical Time-field or Time-particle discovered independent of that concepts use. The notion of 'measuring time' becomes problematic since there is nothing physical being measured; A measurement implies two physical systems interacting or physical conditions being imposed. This is all fine for scientific progress, but when that definition 'runs-away' from its original intended identity with intuition, one should amend Kant rather than think they have refuted him in any resounding way.

Kant did not even claim it is possible to know Reality as it is in itself,.... but the Realists readily claim such knowledge, despite that QM refutes them over and over.

End of rant.
docile
Oct 26, 2015
This comment has been removed by a moderator.
Captain Stumpy
5 / 5 (4) Oct 26, 2015
Shouldn't you be praying at the 'water surface'?
@Noumenon
Ten stars for this one! LMFAO

.

...There are delusions which are selected for, rather than against. One such delusion _might_ be free will. It _might_ be crucial to believe that free will exists in order for our brains to function (e.g. to avoid depression).

The brain is an evolved organ ...we should keep in mind the history (i.e. biases) that come with an evolved organ.
@AA_P
great point! See also: Jonah Lehrer's book, "The Decisive Moment"

I think the problem is in the use of the words "you" and "watching"
@Tear88
yep... and the fact that for us to "watch" means to "measure" and thus interfere or even impart energy
TheGhostofOtto1923
3.7 / 5 (6) Oct 26, 2015
I'm an atheist and could care less about his personal beliefs. His religious beliefs do not negate his career in physics.
No his veiled reality/cosmic hypergod tend to do this.

In this thread
http://phys.org/n...oms.html

-and others I availed nou as to the mystical nature of most all of the people he references.

Theyre all merely trying to keep the fallacy of the existence of a soul and a netherworld alive, where they can go rather than just -end- which is so insulting after all the work theyve done to establish such unique and irreplaceable personas...

More veiled deism and related arguments.
TheGhostofOtto1923
3.4 / 5 (5) Oct 26, 2015
Heres a better one:
http://phys.org/n...ion.html
TheGhostofOtto1923
3.4 / 5 (5) Oct 26, 2015
... Einstein made an operational definition of time and space by transposing that intuition as a stated definition to BE a physical system. This is despite that there has never been an ontological physical Time-field or Time-particle discovered independent of that concepts use. The notion of 'measuring time' becomes problematic since there is nothing physical being measured; A measurement implies two physical systems interacting or physical conditions being imposed. This is all fine for scientific progress, but when that definition 'runs-away' from its original intended identity with intuition, one should amend Kant rather than think they have refuted him in any resounding way.

Kant did not even claim it is possible to know Reality as it is in itself,.... but the Realists readily claim such knowledge, despite that QM refutes them over and over.

End of rant.
...Blah?
TheGhostofOtto1923
3.7 / 5 (6) Oct 26, 2015
Wrt synthetic a-priori blah disproved by the use of non-Euclidean blah for GR.. I don't think that argument is entirely fair, ....albeit legitimate and often repeated. The fifth postulate was already blah way before Kant's time, so it's hard to believe he would hinge his core epistemology on that postulate. I believe what is important wrt his point are the elements of blah as conditions for experience to be possible, time and space,... and not constructions with those elements.

Since, as I mentioned above, in the limit of an observers local experience (reference frame carrying the clock and rod), ....in the tangent space of the Riemann manifold, the geometrical construction reduces to blaaaah (though it is hyperbolic because time is treated with space). So implicit within Einstein's own mathematical formulation, are Kant's conditions for experience
uh - blah!! Try to say something using words which have concrete definitions (not the portland cement kind.)

ok?
Noumenon
5 / 5 (4) Oct 26, 2015
B. d'Espagnat not withstanding, the universe & things in it exist independent of human consciousness. When an individual dies, i.e., is permanently nonconscious, the universe cares not a whit and things keep on existing. Before we discovered, that is, we were conscious of, exoplanets, they existed.


I don't know of anyone whom would claim otherwise. Kant (not an idealist), d'Espagnat, Hawking, Noumenon,... all have empirical reason to believe in an objective reality existing independent of human minds. Before objecting, it's necessary to understand what you're objecting to. If there is a point I could clarify first.....?

Noumenon
5 / 5 (5) Oct 26, 2015
and others I availed nou as to the mystical nature of most all of the people he references.


You've called even Roger Penrose a mystic,.... It's why you have no credibility. d'Espagnat is a well respected physicist who has written extensively on the conceptual foundations of QM. I've reference eminent physicists whom you disparage rather than supply an actual substantive counter point I could work with.
Noumenon
5 / 5 (3) Oct 26, 2015
Since, as I mentioned above, in the limit of an observers local experience (reference frame carrying the clock and rod), ....in the tangent space of the Riemann manifold, the geometrical construction reduces to Euclidean (though it is hyperbolic because time is treated with space). So implicit within Einstein's own mathematical formulation, are Kant's conditions for experience....

Try to say something using words which have concrete definitions (not the portland cement kind.)


Why would I be responsible for your lack of knowledge of the mathematical formulation of general relativity? What is the point of you posts above?
TheGhostofOtto1923
3.4 / 5 (5) Oct 27, 2015
You've called even Roger Penrose a mystic,.... It's why you have no credibility. d'Espagnat is a well respected physicist who has written extensively on the conceptual foundations of QM. I've reference eminent physicists whom you disparage rather than supply an actual substantive counter point I could work with
No, roger penrose called himself a mystic. Ive referenced this before and youve read it before.

You lack credibility because you fail to learn. Youre a dogmatist.
TheGhostofOtto1923
3.4 / 5 (5) Oct 27, 2015
Why would I be responsible for your lack of knowledge of the mathematical formulation of general relativity? What is the point of you posts above?
Im talking about the philo gibberish which you and other philos insinuate belongs in physics discussions simply because youre able to interject these terms.

This is why real physicists get all glassy-eyed when you bother them.

"[Others] note that my 'avoidance of the standard philosophical terminology for discussing such matters' often creates problems for me; philosophers have a hard time figuring out what I am saying and what I am denying. My refusal to play ball with my colleagues is deliberate, of course, since I view the standard philosophical terminology as worse than useless—a major obstacle to progress since it consists of so many errors." -dennett
Elmo_McGillicutty
1 / 5 (2) Oct 28, 2015
Utter nonsense. Watching an event is a passive activity. As soon as you emit any EM, especially on cold atoms, you will see a change. That's not watching. False definitions, false equalities, false inequalities.

Science has been a sham for decades.
my2cts
1 / 5 (2) Nov 01, 2015
I explained above what wave function collapse really is: the consequence of the experimental setup. I gave links to the original paper and to the textbook of the famous L.E. Ballentine.
The discussion can be closed.
rickross
not rated yet Nov 06, 2015
What does this mean in simple layman's terms?
Noumenon
5 / 5 (2) Nov 07, 2015
"The attributes with which physics deals manifest themselves only through experiments and reactions which are based on postulated laws of nature" - Hermann Weyl
Noumenon
5 / 5 (2) Nov 08, 2015
What does this mean in simple layman's terms?


They're observing a new application of a phenoma called the quantum Zeno effect,..... which supresses otherwise expected evolution of a quantum system, simply by making a repeated measurement. A measurement in quantum mechanics effectively "resets" the system which starts to then spread out again....

... but by "spread out" I don't mean in normal space, but rather in the space of possible outcomes for the next measurement. Repeated measurements prevent this spreading out, and so limits possible subsequent measurement outcomes to what was just found.

It's not entirely understood why. It is a matter of interpretation at the moment. It is related to "the measurement problem".

Noumenon
5 / 5 (2) Nov 08, 2015
.... which as I expressed above, believe to be a epistemological problem, ...that it is the result of conflating "observation/measurement" with "quantum interaction" .

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