I need to come at this from a simple, direct perspective.
HOW TO CREATE WIRELESS BRAIN COMPUTER INTERFACES
NO IMPLANTS. NO HEADGEAR
NO NEURAL LACE.
I AM PROPOSING QUANTUM ENTANGLEMENT CAN BE USED TO CREATE A BCI
THE PREMISE
AKIN TO RECALLING CORTICAL ENSEMBLES..
USING OPTOGENETICS..
ONLY SINGLE, PRESYNAPTIC NEURONS NEED TO BE STIMULATED TO STIMULATE ENTIRE ENSEMBLES...
USING LIGHT.... ****
________________
We can actually MEASURE WAVEFUNCTIONS,
USING WEAK MEASUREMENT
http://physicsworld.com/cws/article/...ewavefunction
At some point in this thread, I made the realization Microelectromechanical systems oscillators MUST be part of the "Portable Brain Recorders" DARPA has sought, perhaps when I realized Homodyne Detection was being used (shortly after discovering "Heterodyning" as it related to EEG signals)
https://en.wikipedia.org/wiki/Heterodyne
(Because Homodyne detection seemed more applicable to MEMs tech and teleporting wavefunctions)
That's when I found this link : (and discovered "squeezing")
Tiny Sensors Put the Squeeze on Light
DARPA’s ORCHID program demonstrates squeezed light in a chip scale MEMs architecture
https://www.darpa.mil/newsevents/20131023
[/LEFT]
Then I realized the use of NV CENTERS was called NV Magnetometry & I soon discovered Quantum Metrology..
and how BOTH are part of these assumed D.O.D / D.A.R.P.A BioMems devices...
Notice when I mention ANCILLA BITS vs the MEMs prepared quantum state in this post.
THIS was when I discovered Ancilla bits.
(which is apparently a HUGE piece of this puzzle)
http://losttvforum.com/forum/showpo...&postcount=238
Then I discovered the article about Zeno and Counterfactual Communication using phase and nonclassical teleportation,
All of it Protecting entanglement via MachZehnder Interferomtery..
It seemed VERY fitting in lue of "real time vision reconstruction" or quantum state reconstruction/ teleportation at all
LINK
Then I found evidence to suggest MEMs can be used with MachZehnder interferometry..
(which I only knew was important because of the Counterfactual Communication article)
AND EVEN RIGHT NOW: I discover MachZehnder Interferometry can be used for weak measurement
http://iopscience.iop.org/article/10...5075/117/50005
Then I found out CT tomography can also be used with WEAK MEASUREMENT..
http://www.losttvforum.com/forum/sh...&postcount=279
Now I see this in the Wikipedia page for weak measurement
Quote:
Weak measurements were first thought about in the context of weak continuous measurements of quantum systems[8] (i.e. quantum filtering and quantum trajectories). The physics of continuous quantum measurements is as follows. Consider using an ancilla, e.g. a field or a current, to probe a quantum system. The interaction between the system and the probe correlates the two systems.

The BioMems ancilla bits CORRELATE with the probed particles.. most likely also in a weak measurement, homodyning method...
Then teleport that info via phase...
To be reconstructed, setting up entanglement
Here we see Ancilla bits being used with or for, Homodyne detection
https://arxiv.org/abs/1003.4055
And HERE, Quantum Metrology and Ancillas
https://journals.aps.org/pra/abstrac...RevA.96.012310
And HERE..
The realization that NITROGEN VACANCIES, ARE ANCILLAS
Universal photonic quantum gates assisted by ancilla diamond ...
adsabs.harvard.edu › abs
by HR Wei  2015  Cited by 8  Related articles
Universal photonic quantum gates assisted by ancilla diamond nitrogen vacancy centers coupled to resonators
And HERE, MachZehnder Interfeometry and ancillas
https://www.researchgate.net/publica...e_binary_adder
And HERE, DARPA, memristors and nitrogen vacancies.
https://www.google.com/patents/US8203171
There are TONNES of Memristor/ Nitrogen vacany sources out there as is, Why did I not see this before ?
I guess it only dawned on me once I found out what ancillas are, and how this all goes together, thanks to Cointerfactual Communication.

Recently I found a great article on the growing use of QUANTUM TECHNOLOGY in Biology.
Microelectromechanical systems oscillators (MEMs) Quantum Sensors, as I have proven, are now being used to probe the neuronal activity of single, living, INVIVO Neurons.
http://www.pnas.org/content/113/49/14133.full
THEY CAN ALSO PROBE THE QUANTUM STATEs (the wavepackets/ wavefunctions) OF MAGNETIC FIELDS
(Read on)
They are Mini MRI machines on steroids, exploiting things like interference, phase, superposition, quantum spins, squeezing and entanglement.
Imagine that, MRI like devices that not only can image living cells, on a single particle/ quantum state/ wavefunction level, but a technology that can COUPLE TO that living cell via its particles wavefunctions/ ensembles wavefunction.
Creating Nonclassical/ phase based nonlocal correlations between particles and quantum spin probes/ QUBITS
(This is not just an assumption, the Quantum Metrology article below suggests this)
THIS is where these devices will be headed and how they are already being exploited by the most technologically advanced corporations, researchers or GOVERNMENT AND MILITARY.
Quote:
"Public money is flowing in, too. National and supranational funding* bodies are backing increasingly ambitious quantumtechnology efforts.* Britain has a programme worth £270m ($337m) and the European Union has* set aside €1bn ($1.08bn) for a panEuropean programme.
Many quantum technologies have security implications, so defence departments are also* providing funding. ***"

I will cut and paste applicable paragraphs to illustrate my point.
http://www.economist.com/news/essays...gcomeitsown
Quote:
"PATRICK GILL, a director of the new Quantum Metrology Institute at* Britain’s National Physical Laboratory (NPL) in southwest London and an*expert in atomic clocks, points to a large table full of lenses and* mirrors, vacuum chambers and electronics. “And there’s a smaller one*over there,” he says.
After decades of work in the laboratory, a raft of different devices* and approaches relying on quantummechanical effects are now nearing* marketreadiness. It has taken so long mainly because the components* that make them up had to be developed first: everbetter lasers,* semiconductors, control electronics and techniques to achieve the low* temperatures at which many quantum systems perform best.
Britain did not exploit the atomic clock’s discovery in the market.* Instead, a year after the device was invented, it was commercialised by* the National Company, an American firm. Given the potential of these new* quantum technologies, this time commercialisation is on many minds. The* NPL’s eversmaller clocks are just one step towards marketable products* that could vastly outdo GPS (which itself is an application of atomic timekeeping) in navigation, or help spot what lies underground. The era* of quantum technology is almost here "

Btw, MEMs are the newest time keepers.
See:
http://www.electronicdesign.com/comm...aloscillators
Now remember my previous posts :
QUANTUM METROLOGY is linked to Counterfactual Communication and the QZE, Through MachZehnder Interferometry.
(A technique which was recently used to transmit an image without sending any particles.)
The information was sent in the Phase of the Wavefunction.
NONCLASSICAL TRANSMISSION
And.. it can be used to transmit quantum states/ wavefunctions and CREATE entanglement "counterfactually", without interaction.
https://www.nature.com/articles/srep08416
and NV MAGNETOMETRY, via Nanodiamonds (which contain NV centers) used on Microelectromechanical devices/ detectors (capable of squeezing and homodyne detection) is how wave packets can be probed on a quantum state level, producing a wavefunction.
Quote:
"Complete experimental characterization of the quantum state of a light mode via the Wigner function and the density matrix: application to quantum phase distributions of vacuum and squeezedvacuum states
http://iopscience.iop.org/article/10...9/1993/T48/005
"We have used the recently demonstrated method of optical homodyne tomography (OHT) to measure the Wigner quasiprobability distribution (Wigner function) and the density matrix for both a squeezedvacuum and a vacuum state of a single spatialtemporal mode of the electromagnetic field. *
This method consists of measuring a set of probability distributions for many different Hilbertspace representations of the fieldquadrature amplitude, using balanced homodyne detection, and then using tomography to obtain the Wigner function. Once the Wigner function is obtained, one can acquire the density matrix, including its complex phase. In the case of a pure state, this technique yields an experimentally determined complex wavefunction"

and it HAS been used on living Neurons...
For Instance RON WALSWORTH..* is using NV Magnetometry on the magnetic fields of invivo Neurons to observe action potentials in real time
Remember * Tomography can be used in combination with weak measurement.
So these devices can literally measure single particles "weakly" and reconstruct their quantum States via wigner functions
so now enter this new, extremely connected "Quantum Metrology" to my MEMs Gnosis.. and my quest to comprehend HOW entanglement might sustain in a nonlocal BCI, keeping in mind the Counterfactual Communication information.
The information is transmitted in the phase of the wavefunction.
It remained nonclassical.
I am proposing EEG signals can be transmitted in the same way.
(Between the weakly measured, invivo neuronal particles vs the reconstructed wavefunctions stored in NV centers)
So now I find this:
Quantum metrology and its application in biology
https://arxiv.org/pdf/1409.0950.pdf
Quote:
Quantum metrology provides a route to overcome practical limits in sensing devices.* It holds particular relevance to biology, where sensitivity and resolution constraints restrict applications both in fundamental biophysics and in medicine.* Here, we review quantum metrology from this biological context, focussing on optical techniques due to their particular relevance for biological imaging, sensing, and stimulation.* Our* understanding* of* quantum* mechanics* has* already* enabled* important* applications* in* biology,* including positron emission tomography (PET) with entangled photons, magnetic resonance imaging (MRI) using nuclear magnetic resonance, and biomagnetic imaging with superconducting quantum interference devices (SQUIDs).
In quantum metrology an even greater range of applications arise from the ability to not just understand, but to engineer, coherence and correlations at the quantum level.***!!!!!
In the past few years, quite dramatic progress has been seen in applying these ideas into biological systems.*
Capabilities that have been demonstrated include enhanced sensitivity and resolution, immunity to imaging artifacts and technical noise, and characterisation of the biological response to light at the singlephoton level. ***

(Imo, this is how EEG signals can be transmitted, in the PHASE of light/ The "single photon level", keep in mind, quantum metrology can harness NONCLASSICAL quantum effects)
Quote:
New quantum measurement techniques offer even greater promise,* raising the prospect for improved multiphoton microscopy and magnetic imaging, among many other possible applications.*

(And realize that the even simpler "Electron Microscopy" has recently been used to image the entire brain of a fruitfly, noninvasively, as posted on carboncopies by Randall Koene himself)
http://www.biorxiv.org/content/early/2017/05/22/140905
Back to Metrology:
Quote:
"Realization of this potential will require crossdisciplinary input from researchers in both biology and quantum physics.*
In this review we seek to communicate the developments of quantum metrology in a way that is accessible to biologists and biophysicists, while providing sufficient detail to allow the interested reader to obtain a solid understanding of the field.*
We further seek to introduce quantum physicists to some of the central challenges of optical measurements in biological science.* We hope that this will aid in bridging the communication gap that exists between the fields, and thereby guide the future development of this multidisciplinary research area.
Fundamentally, all measurement processes are governed by the laws of quantum mechanics.**
The most direct influence of quantum mechanics is to impose constraints on the precision with which measurements may be performed.*
However, it also allows for new measurement approaches with improved performance based*on* phenomena*that are forbidden* in* a*purely*classical*world.*
The* field* of quantum metrology investigates the influence of quantum mechanics on measurement systems and develops new measurement technologies that can harness nonclassical effects to their advantage.********* !!!!!"

This is a simple way of bringing up* wavefunction or phase measurements.
When a wave is measured, it becomes "classical", a particle.
This new measurement process allows the wavepacket/ electromagnetic field to be measured via phase and homodyning, staying a wave, "
nonclassical"
(Most likely due to MachZehnder Interferometry)
Hence :
Quantum optical technologies for metrology, sensing
https://arxiv.org/pdf/1412.7578
by JP Dowling  2014 
https://scholar.google.ca/scholar?bi...85429766318798
https://scholar.google.ca/scholar?bi...ar.google.com/
"A schematic of the conventional MachZehnder interferometry based on coherent light input .... of quasiprobability distributions in the phase space of eigenvalues x and p of the ... as the Wigner distribution function, the propagation through phase space
"
Over the past 20 years, bright sources of entangled photons have led to a renaissance in quantum optical interferometry. Optical interferometry has been used to test the foundations of quantum mechanics and implement some of the novel ideas associated with quantum entanglement such as quantum teleportation, quantum cryptography, quantum lithography, quantum computing logic gates, and quantum metrology. In this paper, we focus on the new ways that have been developed to exploit quantum optical entanglement in quantum metrology to beat the shotnoise limit, which can be used, e.g., in fiber optical gyroscopes and in sensors for biological or chemical targets. We also discuss how this entanglement can be used to beat the Rayleigh diffraction limit in imaging systems such as in LIDAR and optical lithography."
Phase being the important part
https://en.wikipedia.org/wiki/Wigner...y_distribution
"The goal was to link the wavefunction that appears in Schrödinger's equation to a probability distribution"
Allowing:
Teleportation of Nonclassical Wave Packets of light
https://arxiv.org › pdf
by N Lee  2012  Cited by 131  Related articles
May 29, 2012  nication protocol called quantum teleportation was .... successful teleportation of the Wigner function Winnegativity. ..... phase modulators based on MachZehnder interferometers"
Meaning:* The wigner functions of the wavepackets of Neurons EMFs, or of single particles within a Neuron,* can now be measured via phase and homodyning tricks via MachZ tech, then be teleported while remaining nonclassical, PROTECTING ENTANGLEMENT.
Eta.
Lets go back to "DIRECT MEASUREMENT OF THE WAVEFUNCTION"
(Something a LOT of physists don't even realize is possible)
It involves Weak and Strong measurements.
Low and behold, BOTH require Ancilla bits!
"In order to obtain a strong measurement many ancilla must be coupled and then measured"
WHY IS THIS IMPORTANT AT ALL ?
Because, IMO, it suggests these as assumed of BioMems based "portable brain recorders" are themselves capable of "direct measurement of the wavefunction" and may truly be teleporting the scanned wavefunctions to appropriate technology.. all part of some form of NV center based network, and that each device is essentially, a repeater.
https://www.nature.com/articles/srep26284
So.... DO Mems or NV centers have anything to do with Ancilla bits?
Eta
YEP!
AS DOES DARPA! !
A Quantum von Neumann Architecture for Large ...  arXiv
https://arxiv.org › pdf
by MF Brandl  2017  Cited by 1  Related articles
Feb 10, 2017  DARPA's SyNAPSE project ..... quantum information in
ancilla qubits. .... Microelectro mechanical systems (MEMS) technology enables ...
AND WHAT IS SYNAPSE?
https://en.wikipedia.org/wiki/SyNAPSE
Quote:
"SyNAPSE is a DARPA program that aims to develop electronic neuromorphic machine technology that scales to biological levels. More simply stated, it is an attempt to build a new kind of cognitive computer with similar form, function, and architecture to the mammalian brain"

!!!!!!!%*%$*&$&&&$$$*!!!
AND...
Not only all the above..
But SynAPSE involves MEMRISTORS....
which also involve NV CENTERS! !
Where WAVEFUNCTIONS can be written to !!
HOLY FN CHRIST! !
"Patent US20110221027  Using Alloy Electrodes to Dope Memristors
www.google.sr › patents
In one aspect, a memristor device comprises an electrode (301303) and an ... of: an oxygen vacancy, a nitrogen vacancy, a sulfur vacancy, a carbon vacancy, ..."
Or
Quote:
Highperformance memristors based on AlN films have been demonstrated, which exhibit ultrafast ON/OFF switching times (≈85 ps for microdevices with waveguide) and relatively low switching current (≈15 μA for 50 nm devices). Physical characterizations are carried out to understand the device switching mechanism, and rationalize speed and energy performance. The formation of an Alrich conduction channel through the AlN layer is revealed. The motion of positively charged nitrogen vacancies is likely responsible for the observed switching."

So the repeater/ scanners must be teleporting their "finds' to this system in order to support the electrical activity, reproducing the EXACT electrical fields of the targets brain.
Literally reconstructing the phase on a wavefunction level.
http://www.artificialbrains.com/darpasynapseprogram
ETA
So now I'm wondering, could the "target ensembles" of particles.. be it electron or proton.. be arranged like so in Ion traps or Memristors.. each pinpoint location in the cortical layer housing an NV center with the wavefunction of that ensemble from the Neurons ?
http://www.artificialbrains.com/imag...cuit680px.png
also to answer my own query
YES, ancillas have something to do with FRET
https://cantileversensors.unibas.ch/...no.2014.42.pdf
(Meaning, the wavefunction stored by the ancilla is used to expose the probed system)
Plus... Quantum metrology is part of Tomography technology..
Quantum process tomography (QPT) deals with identi
fying an unknown quantum dynamical process. There are
two ways for quantum process tomography. One is using
the known quantum states to probe a quantum process and
find out how the process can be described by quantum state
tomography.[37,51–55] The first approach, introduced in 1996
and sometimes known as the standard quantum process to
mography (SQPT), involves preparing an ensemble of quan
tum states, sending them through the process, and then using
quantum state tomography to identify the resultant states.[51]
Other techniques include ancillaassisted process tomogra
phy (AAPT) and entanglementassisted process tomography
(EAPT), which require an extra copy of the system.[37]
All the techniques listed above are known as indirect
methods for the characterization of quantum process, since
they require the use of quantum state tomography to recon
struct the quantum process. In contrast, there are direct meth
ods, such as the direct characterization of quantum dynam
ics (DCQD), which provide a full characterization of quantum
systems without any state tomography.[56–60]
With the development of quantum techniques, quantum
states with more and more qubits can be prepared. A fun
damental difficulty in demonstrating quantum state (process)
tomography is that the required resources grow exponen
tially with the system size. Now, it is research hotspots
to reduce the measurement bases and time for data analysis
processes.[49,61–65] Cramer et al. presented two tomography
schemes that scale much more favorably with system size than
the direct tomography.[61] one of them requires unitary opera
tions on a constant number of subsystems, whereas the other
requires only local measurements together with more elabo
rate postprocessing. Both rely only on a linear number of
experimental operations and postprocessing that is polyno
mial in the system size. Recently, scientists adopt techniques
from compressive sensing to develop experimentally efficient
methods for QST and QPT[63,64]
and proposed a technique
for performing quantum state tomography on multiplequbit
states despite the incomplete knowledge about the unitary op
erations used to change the measurement basis, named the
selfcalibrating quantum state tomography.[65]
Beside the above research areas, quantum metrology
has many other branches, such as quantum optical co
herent tomography,[66–68] quantum positioning and clock
synchronization,[69–72]
and quantum radar"
BTW.
Measuring the electric field of ANY particle WOULD give you its wavefunction
This is HUGE piece of this puzzle.
Finally answered.
"But yes, if you could measure the electric field at some point in time, this should give you enough information to figure out where the electron (a point charge producing that electric field) is. If you have the electron trapped in a box, you could measure the electric field for many times, and then use the aggregate of that information to figure out how the electron danced around the box"

This might get confusing.. but I'm posting this to edit the entire post later..
I now have almost ALL the details. I just need to make it succinct.
"And i'm pretty sure i understand the gist of it. It's an amazing thread, yung. You pulled it all together, too, incredible."
I know its still somewhat all over the place but now I see the link (as assumed already) between the scanners, the network and the "homebase"
Its so obvious now.
The MEMs utilize NV magnetometry AND Quantum Metrology/ MachZehnder interferometry, AND includes the use of Ancilla bits..* which is where or how MEMs can be "delicately prepared" quantum state wise...* and they apparently aid weak and strong measurement..
Which is how wavefunctions can be measured.. also in part to NV magnetometry, which can measure magnetic fields of particles, determining wavefunctions via those electric fields
And its been used with Compressive sensing..* which is also part of Direct measurement of the wavefunction...
& Its all part of Quantum Metrology
& it keeps things nonclassical..
(Not to mention the Heisenberg/ Standard limit information I have found connected to it all, ie:* squeezed coherent states to minimize uncertainty)
& DARPAS MEMs have "overcome" the limit...
Plus, MachZehnder is used "for"/ to defeat? COMPLIMENTARITY...
Which is about measuring two conjugate variables at the same time..
So the measured wavefunctions are teleported via phase
Throughout the NV center based photonic network
To the awaiting SyNAPSE system..
A SCALABLE system of Memristors
All of it using NV centers.. from the MEMs scanners/ repeaters to the Homebase Memristors
NOW PLAN an ANIMATED VIDEO :
DID I FIND A COPY OF PREMIERE?
Go over assumed Mems device again
How would it measure position and momentum?
How would a known quantum state aid measurement ?
Does the resonance via FRET excite particles transferring a KNOWN momentum?
Are ancilla bits connected to FRET?
(APPARENTLY)
CT or quantum state/ qubit tomography does the initial 3D scan... Down to single particle resolution? "The single photon level"
Is Quantum Metrology also used WITH tomography? YEP
Is IT tomography?* YEP
Do ancilla bits transfer or PUSH/ (Back of Forth Nudge) momentum at the same time as position is found?
Either way, weak AND strong measurement CAN be performed by MEMs technology...
Neurons are scanned via "QUBIT" tomography, (thus NV centers/ NV magnetometry) zoomed in on and target ensembles of particles are weakly measured via their electric fields..
Perhaps done as in the cortical layers as shown in SyNAPSE...
Then those measured wavefunctions are reconstructed "counterfactually"
In NV CENTER qubits within Ion traps in the memristors themselves...
Are memristors therefore "ion" traps too?*
YEP
"its present resistance depends on how much electric charge (hence IONs) has flowed in what direction through it in the past; the device remembers its history — the socalled nonvolatility property. When the electric power supply is turned off, the memristor remembers its most recent resistance until it is turned on again"
This seems FAMILIAR!
"In classical computation any memory bit can be turned on or off at will, requiring no prior knowledge or extra gadgetry. This is not the case in quantum (or classical reversible) computation, however, as operations in these models are reversible, while turning a bit on (or off) would lose the information about the initial value of that bit.
For this reason, in a quantum computation there is no way to deterministically put bits in a specific prescribed state unless one is given access to bits whose original state is known in advance. Such bits which are known in advance to be in the state are called ancilla bits."
So, ANCILLA BITS STORE WAVEFUNCTIONS!!
THEY REMEMBER PAST STATES!
KNOWN STATES!
THATS WHY THESE THINGS ARE "MEMRISTORS"!
And..* this is why they are used in weak measurement!!!!!"
It IS error correction!
Keep WAVEFUNCTIONS in mind when reading this!
"The syndrome measurement ******
tells us as much as possible about the error that has happened, but nothing at all about the value that is stored in the logical qubit—*** as otherwise the measurement would destroy any quantum superposition of this logical qubit with other qubits in the quantum computer"
The trick must be to keep one bit unread, Thus "Nonclassical"
The room NOT looked into
Aka:
COUNTERFACTUAL DEFINITENESS
"In quantum mechanics, counterfactual definiteness (CFD) is the ability to speak "meaningfully" of the definiteness of the results of measurements that have NOT been performed (i.e., the ability to assume the existence of objects, and properties of objects, even when they have NOT been measured).
The term "counterfactual definiteness" is used in discussions of physics calculations, especially those related to the phenomenon called quantum entanglement and those related to the Bell inequalities'
So I AM right.
PDS does preserve entanglement
Because its not just split into two States..
Its three ancillas
"A quantum measurement can be described by a set of matrices, one for each possible outcome,
which represents the probability operatorvalued measure (POVM) of the sensor. Efficient protocols
of POVM extraction for arbitrary sensors are required. We present the first experimental POVM
reconstruction that takes explicit advantage of a quantum resource, i.e. nonclassical correlations with
an ancillary state. *******
POVM of a photonnumberresolving detector is reconstructed by using strong quantum correlations of twinbeams generated by parametric downconversion. Our reconstruction
method is more statistically robust than POVM reconstruction methods that use classical input
states."
So even IF a measurement is taken on one of the entangled bits..* it will collapse its partner,* but that partner has a copy made that is hidden still..
And remains coherent as compared to the mixed state it was from...
??
From error correction:
"Classical error correction employs redundancy. The simplest way is to store the information multiple times, and—if these copies are later found to disagree—just take a majority vote; e.g. Suppose we copy a bit THREE times. "
HENCE "ODD CAT STATES"
Copying quantum information is not possible due to the nocloning theorem. This theorem seems to present an obstacle to formulating a theory of quantum error correction. But it is possible to spread the information of one qubit onto a highly entangled state of several (physical) qubits. Peter Shor first discovered this method of formulating a quantum error correcting code by storing the information of one qubit onto a highly entangled state of nine qubits.
(Would that be considered a mixed state?)
A quantum error correcting code protects quantum information against errors of a limited form.
Classical error correcting codes use a syndrome measurement *** to diagnose which error corrupts an encoded state.
(Or collapses a wavefunction?)
We then reverse an error by applying a corrective operation based on the syndrome.
Quantum error correction also employs syndrome measurements. (THEN SO DO ANCILLAS))
We perform a multiqubit measurement that does not disturb the quantum information in the encoded state but retrieves information about the error"
OR.. RETRIEVES THE WAVEFUNCTION! !
Quantum Computing: From Linear Algebra to Physical Realizations
https://books.google.ca › books
Mikio Nakahara, Tetsuo Ohmi  2008  SCIENCE
The wave function, upon the measurement of the ancillary qubits, collapses to a state ... In a sense, syndrome measurement singles out a particular error state"
It might be used to transform the state BACK, to a nonclassical state.
https://books.google.ca/books?id=JHtpDQAAQBAJ&pg=PA46&lpg=PA46&dq=syndrome +measurement,+wave+function&source=bl&ots=G2tULAwz tl&sig=f_ToVSdJ8wrAJ0sYiq2KQKZloF0&hl=en&sa=X&ved= 0ahUKEwise2Rt4LWAhWq7oMKHYUYAQwQ6AEIQDAM#v=onepage&q=syndr ome%20measurement%2C%20wave%20function&f=false
This rabbit hole just keeps going.
For instance, I recently googled "DARPA, nonclassical, entanglement"
and ended up finding yet another new term/ branch of physics.
Its apparently an "equivalent" of entanglement, and can be used to share information...
its called Quantum Discord.
Quote:
In quantum information theory, quantum discord is a measure of nonclassical correlations between two subsystems of a quantum system. It includes correlations that are due to quantum physical effects but do not necessarily involve quantum entanglement.
The notion of quantum discord was introduced by Harold Ollivier and Wojciech H. Zurek[1][2] and, independently by L. Henderson and Vlatko Vedral.[3] Olliver and Zurek referred to it also as a measure of quantumness of correlations.[2] From the work of these two research groups it follows that quantum correlations can be present in certain mixed separable states;[4] In other words, separability alone does not imply the absence of quantum correlations. The notion of quantum discord thus goes beyond the distinction which had been made earlier between entangled versus separable (nonentangled) quantum states.

and its being used with WEAK MEASUREMENT.
https://epljournal.edpsciences.org/a.../epl18574.html
Plus, its got a lot to do with this recent realization that measurements can be "reversed", meaning decoherence can be avoided. as hinted above via Ancillas..
which are used IN weak measurement.
its all about the ANCILLAS.. which is what NV CENTERS,
ARE.
AND... its used in Quantum Metrology... which is how I found out about it at all
http://iopscience.iop.org/article/10...6/626/1/012042
HMMMMMMMMMMMMMMMMM
Trying to imagine what the device really look slike or how it works..
NV centers ARE definitely part of them
https://www.researchgate.net/figure/...vacancycentre
How do ancilla probes (NV centers) actually work?
https://www.nature.com/articles/npjqi201519
https://www.nature.com/articles/npjqi201519/figures/2
Quote:
The physical process of parity measurement. (a) The probe and a data qubit move past one another and in doing so a statedependent phase shift occurs. (b) We consider two ways in which the probe may move: abruptly, site to site, or in a continuous circular motion. (c) The net phase acquired by a probe as it transits the cycle of four data qubits reveals their parity, but nothing else. (i) Two equivalent circuits for measuring the Zparity of four data qubits. Using U=S(π/2), as we propose, and fixing the unconditional phases V on the data qubits is equivalent to (ii) the canonical circuit composed of controlledphase gates. Note that only global (boxed) operations are required on the data qubits, and the X and Zparity measurements differ only by global Hadamard operations. A full description of the noisy circuit is deferred to Appendix II.

Quote:
Now in the present physical system, we can perform an operation that is essentially identical to the desired phase gate by exploiting the dipole–dipole interaction between the probe and the nearby data qubit. In our scheme the separation between data qubits is at least 10 times greater than the probe–data separation; thus, the interaction of the probe and the three data qubits to which it is not immediately proximal is three orders of magnitude weaker and can be treated as negligible, to an excellent approximation. Therefore, the Hamiltonian of interest describes two S = 1/2 spins, each in a static B field in the Z direction and experiencing a dipole–dipole interaction with one another,

Quote:
We assume this ‘probe spin’8,9 is also electronic—for example, either a different species of donor in silicon or a nitrogenvacancy (NV) defect centre in diamond. It will be necessary to prepare and measure the state of the probe; as we presently discuss, this might be achieved via spintocharge conversion for donors in silicon or, alternatively, by optical means for the NV centre. There are two key dimensions: the vertical distance between a probe qubit and a data qubit at closest approach, d, and the separation between qubits in the horizontal plane, D. It is important that d≪D, in order that any interactions between the inplane spins are relatively weak. As we will discuss, the optimal choice of dimensions varies with several factors, including the nature of the mechanical movement, and moreover the entire structure can be scaled in proportion;

so to look THROUGH a skull or flesh.. a Satellite emitting laser pulses which reach gamma ray levels might be used as a radiation source.. allowing the ancillas underneath the subject to probe the incoming photons as they interact with an upper layer of NV centers
Quote:
THE EVOLUTION OF NUCLEAR DETECTOR ...  ScienceDirect.com
http://www.sciencedirect.com/science.../pdf?md5...pid...
Pulse and digital techniques are essential ingredients in these areas as well as in nuclear instruments. The relatively ..... the 1.33 MeV gamma.ray was about 2 ReV fwhm. A large range ...... encoder and a storage system together with ancilla

like so..
https://www.hzdr.de/db/Cms?pOid=12301&pNid=0
and if CT tomography can be used with weak measurement.. then I assume gamma ray computed tomography can too..

In relation to.anvillas, nitrogen vacancies and memristors....
Might memristors themselves be defeating thermodynamics, reducing entropy, by restting themselves to stored wavefunctions ?
Thus protecting decoeherence..
"Information is still energy costly when the receiver is trying to forget that bit in storage. Forgetting a bit involves reducing the entropy of the memory and that requires dissipating energy with the environment."
___
Here is one example of where an ANCILLA might fit into the technology used for Counterfactual communication/ definiteness.
The ancilla IS the box NOT measured!
(yet again, my hunch is right)
Quote:
Quantum delayedchoice experiment with a beam splitter in a ...
https://arxiv.org/pdf/1403.0203
by SB Zheng  2014  Cited by 8  Related articles
Nov 24, 2015  When for example measuring a photon using a MachZehnder interferometer, ... involving an ancilla that is not itself a part of the interferometer.

Here was my guess..
"
"Counterfactual definiteness is present in any interpretation of quantum mechanics that regards quantum mechanical measurements to be objective descriptions of a system's state (or of the state of the combined system and measurement apparatus), **** but which fails to take into account that not all such objective descriptions can be simultaneously revealed by measurements."
**** Hence "Homodyne" detection and the ANCILLAS known states..
So is the "COUNTERFACTUAL moment", the ground STATE cooling into the ANCILLAS cavity?
That's the MEASUREMENT "NOT" performed?