> "A thing is as it is because the universe is as it is. Considering the endless list of factors required for anything to happen, one can only admit that everything is responsible for everything, however remote." ~ Nisargadatta
If I might make an analogy, there seems to be something like a perceptual bow-wave running ahead of events in human lived experience. A programmer friend of mine (NASA and global banking transactions) Told me about a meta-monitor of all internet activity, which was put together in the early 1990s, and which shows a sharp uptick in activity ahead of big human events, such as a big uptick about 13 hours before the attacks of 9/11/01. This is monitored by the intelligence apparatus.
It is sensitive, but completely non-specific.
I experience a heaviness a day or two before big, heavy events with other people, not things I know will happen. I have learned to lean into this with compassion meditation to accept the heaviness before the event, even though I don't know what or when. This seems to help me be clear headed, energetic and efficacious in the actual events.
I am just putting this out there as either hearsay or my subjective experience of my life, not as anything which could be a proof of any sort to anybody else.
The premonitions we receive from the future, while undoubtedly real, always seem to be quite fuzzy and garbled. Usually it's nothing more than a feeling; when in the form of a premonitory dream, it's communicated with vague imagery. In all cases it seems to be open to a great many possible interpretations, and it often seems that it doesn't make sense until the relevant event has been encountered.
This seems like it must be related to the QM principle that the correlation between entangled particles cannot be verified until they can be compared directly.
Most dreams are just processing daily experience. Precognitive dreams have quite a distinct feel to them, or at least, those who have experienced them (I am not among them) are quite adamant that this is so.
Nice article - and it's lovely to see the complexities of quantum correlations and entanglement being discussed.
I don't really agree that this physical system (with violation of the Bell Inequality (BI)) shows that either Alice's (or Bob's) measurement affects the results of measurements of Bob (or Alice).
If you look at this from the perspective of the reduced density matrix then Alice's measurement does not alter Bob's and vice versa.
You don't even need correlated particles to see a violation of the BI. It can be observed with a single particle. In the standard version of the BI with a spin-1/2 particle Alice and Bob will measure the spin at 3 angles, typically chosen at zero, 60 and 120 degrees. They'll choose these directions at random and record their results. When they compare notes later they will find a violation of the BI, if the particles are quantum correlated (eg a singlet state).
Now suppose Alice *prepares* a spin-1/2 particle, at random, in one of the six possible states chosen from the set (angle of measurement, up/down) and sends that on to Bob. Bob will do his random measurement thing as he would for a BI experiment. When they later compare notes there is a violation of the BI between Alice's preparation data and Bob's measurement data.
The key feature here is that violations of the BI are observed in joint *data* - lists of numbers - and the statistical properties observed in this data cannot be explained with a classical model of probability.
Together with a colleague, I published a paper on this and showed how it could be used as an alternative to using correlated particles for one form of quantum key distribution.
But it also has implications for what the BI is telling us. In essence, it harks back to Boole who showed that if you have 3 binary random variables with a joint distribution P(A,B,C) then the marginal joint probabilities like P(A,B), P(A,C) etc are constrained by an inequality. This is the BI. Boole, of course, was using a classical assumption that the variables 'existed' (had definite values) in an objective sense outside of measurement.
It is, as you pointed out, tied into complementarity and the downstream consequence of that which is the uncertainty principle.
It's my view that the BI is telling us about the property of realism, assumed by classical physics, and is not about the locality (i.e causality) aspect - but that's very much a non-standard view and I'm probably wrong on that score.
Particles are created in antimatter opposites. There are multiple mirror symmetries (charge, momentum, polarization, angular momentum etc.) comparing two particles that were created from photons or particle collisions. If 2 photons are created at some point in space such that nothing else affects their phase, polarization or whatever else you can measure on a photon, then those 2 photons leave each other in opposite directions, with mirror opposites of multiple types of measurements (spin orientation, momentum, whatever). Even one thousand light-years away, traveling through a perfect vacuum, they are mirror opposites in some measurement ( I don't have the expertise to describe the various types of measurement that can be done, though I do know quite a bit about it for a mechanical engineer). So why does *almost* everyone write that measuring one affects the other and not bring up the fact of mirror symmetries that can travel thousands of light years away from the starting point?
Everyone please respond to my answer. I rarely see people write about what I just described although I know it is out there. I would like to see others similarly curious about this and if people can describe it better than I can.
"Mirror symmetries that can travel thousands of light years away from the starting point..."
This was exactly what Einstein was proposing in 1935, and exactly what Bell (1964) demonstrated was an inadequate explanation. He demonstrated that there is no getting around the fact that what Alice does affects Bob's particle, whether she does it before or after Bob's measurement.
The proof is a little more technical than I want to get into, but Nick Herbert did the best job of making it accessible, in his book (Quantum Reality) or on this web page: https://www2.cruzio.com/~quanta/bell.html
My guess is that something in the initial assumptions of the proof is resulting in the (incorrect) spooky action at a distance conclusion. Can you put into words, better than I can, this assumption ?
Here is my attempt, please add your thoughts on the following paragraph:
The starting assumption, that all physical properties of a photon or particle are random in time, even when there is no measurment, is incorrect. Therefore, removing this starting assumption results in the fact that spooky action at a distance is incorrect. In reality, the production of 2 photons from a single point in space has physical properties (spin orientation, momentum, angular momentum etc.) dependent on the exact conditions (spin orientation, momentum, angular momentum etc.) of the "thing" that created the 2 photons. The two photons produced go off in different directions with mirror symmetry. There is no spooky action at a distance when some property is measured on one of the photons.
Why isn't this the answer or a slightly better worded version of it?
The conclusion is not dependent on anything about randomness in quantum mechanics. The conclusion is robust. The conclusion is that reality is connected and information travels both forward and backward in time.
This is a technical subject, and I've tried to make it as accessible as I know how. If you want to second-guess the physicists, start by understanding the proof. A good place to start is in Nick Herbert's book. https://www.amazon.com/dp/B005KDDTXM
To truly understand the spookiness of quantum entanglement, it is important to first understand quantum superposition. Quantum superposition is the idea that particles exist in multiple states at once. When a measurement is performed, it is as if the particle selects one of the states in the superposition.
For example, many particles have an attribute called spin that is measured either as “up” or “down” for a given orientation of the analyzer. But until you measure the spin of a particle, it simultaneously exists in a superposition of spin up and spin down.
There is a probability attached to each state, and it is possible to predict the average outcome from many measurements. The likelihood of a single measurement being up or down depends on these probabilities, but is itself unpredictable.
Though very weird, the mathematics and a vast number of experiments have shown that quantum mechanics correctly describes physical reality.
The spookiness of quantum entanglement emerges from the reality of quantum superposition, and was clear to the founding fathers of quantum mechanics who developed the theory in the 1920s and 1930s.
To create entangled particles you essentially break a system into two, where the sum of the parts is known. For example, you can split a particle with spin of zero into two particles that necessarily will have opposite spins so that their sum is zero.
In 1935, Albert Einstein, Boris Podolsky and Nathan Rosen published a paper that describes a thought experiment designed to illustrate a seeming absurdity of quantum entanglement that challenged a foundational law of the universe.
A simplified version of this thought experiment, attributed to David Bohm, considers the decay of a particle called the pi meson. When this particle decays, it produces an electron and a positron that have opposite spin and are moving away from each other. Therefore, if the electron spin is measured to be up, then the measured spin of the positron could only be down, and vice versa. This is true even if the particles are billions of miles apart
The claim that "a vast number of experiments have shown that QM correctly describes physical reality" is also misleading. Yes, quantum theory has been used to understand many phenomena that were incomprehensible from classical mechanics. But I wouldn't say it "correctly describes physical reality". It's a useful model that enables us to compute some things well. But most quantum calculations are so difficult that we can't do them. We don't know what QM predicts in most circumstances of interest, so it is only in a few special cases that quantum theory can even be tested.
I assume I found your substack based on an article you wrote on LENR about 1 year ago. I'm a long time cold fusion follower and somewhat of a cold fusion scientist. I like your anti-aging website too - recently I've been reading about Advanced Glycation End Products (AGEs) and how to reduce them. I already drastically reduced my seed oil intake 2 years ago and eliminated most processed foods.
Just to make sure that you know, "a vast number of experiments have shown that QM correctly describes physical reality" is a cut-and-paste from the link that I mentioned - and I don't agree with it. I believe those people who write that quantum mechanics can be described in more classical terms. And you know the limitations of quantum theory as you just wrote. I think the limitations of quantum theory are so big and that the classical interpreation of atoms is *so* good that classical interpretations of the atom are more likely to be correct. I *have* studied the classical interpretation of the atom in my non-physics educated way. Namely I'm speaking of Randell Mills of Brilliant Light Power. If you look him up, disregard his energy invention and focus on his complete re-writing of quantum mechanics.
I have tried to educate people with my website that summarizes a tiny portion of Randell Mills' theory of the atom which can be found here:
note that I show an explanation for the Youngs double slit experiment (others have written the same explanation before I did) based on surface plasmon polaritons which can be found here
I would disagree with some parts of this quote. Both superposition and entanglement are basic to quantum theory, but I wouldn't say that the two concepts are so closely related that you have to understand superposition before you can understand entanglement.
Entanglement = The probability functions in QM (the wave functions) apply not to individual particle positions but to entire configurations of many particles. There is a probability of a set of particles all being in particular places.
Superposition = These same wave functions can be added and subtracted in arbitrary combinations.
Both these concepts, entanglement and superposition, derive from the fundamental quantum concept that in general we can't know exactly what is where, but we're limited to describing the world in terms of these probability functions.
They are intimately connected. Entanglement arises as a consequence of superposition in a Hilbert space that is the tensor product of two Hilbert sub-spaces.
It's easy to say "everything is connected to everything else", and we might shrug that off because it is true even in Newtonian physics. In Newtonian physics, it's true in the sense that every particle came from the Big Bang, and they all interacted and affected each other in the deep past.
Quantum physics is stranger than this PRECISELY BECAUSE IT IS MORE DEEPLY CONNECTED. Particles are certainly entangled in pairs, as we talk about in the context of Alice and Bob, and what Alice does over here affects Bob's particle over there. But this is just the most trivial case. Quantum physics says that entanglement is universal. If you pick up a solid piece of anything, then all the electrons in that solid are part of the same wave function, and they can't be treated, even approximately, as though they were independent particles. This is the most radical truth of QM.
Yes, it is absolutely correlated to the distance between Alice and Bob. But there is no reason, in principle, why this distance cannot be large, and the two particles don't have to be moving at the speed of light, so the distance can be that much smaller, and still the time difference can be maintained.
I believe the most important part of this theory, are its implications in daily life.
As a Buddhist, I have been taught that the ultimate law is the law of cause and effect. It is inescapable.
Further, this causality stretches in all directions, and there are teachings concerning latent and manifest effects, present affecting both future and past , plus more. I am no scholar, this is just the surface.
More and more science is validating Buddhist teachings from 2500 years ago.
Interconnectedness of all life, and causality with retro causality point to a truly hopeful message in daily life.
Your actions, words and thoughts do affect the entire universe, and each person can affect reality, not only for themselves , but also for others.
The karmic connections with those closest to you enhance this effect, but what really matters is your intention, irrespective of your theoretical knowledge.
So, although through past intentions (spanning eternity, not just this lifetime) you may accumulate a set of effects, considered as 'destiny', you are truly able to change this set, by new intentions.
That is real hope. And of course true responsibility.
Finally, this interconnectedness with all life suggests that a single life entity may affect the entire universe, and this means, as my mentor put it, that an inner change in a single human being, can change the destiny of the entire human kind.
Components of the angular momentum, or "spin" in two different planes. (Actually, there are 3 different planes, all mutually complementary. If you know the spin in the xy plane, you lose all information about spin in the xz plane and also the yz plane.
Wisdom from a modern sage:
> "A thing is as it is because the universe is as it is. Considering the endless list of factors required for anything to happen, one can only admit that everything is responsible for everything, however remote." ~ Nisargadatta
Thank you, Josh. Always appreciate your thoughtful reflections . . . .
If I might make an analogy, there seems to be something like a perceptual bow-wave running ahead of events in human lived experience. A programmer friend of mine (NASA and global banking transactions) Told me about a meta-monitor of all internet activity, which was put together in the early 1990s, and which shows a sharp uptick in activity ahead of big human events, such as a big uptick about 13 hours before the attacks of 9/11/01. This is monitored by the intelligence apparatus.
It is sensitive, but completely non-specific.
I experience a heaviness a day or two before big, heavy events with other people, not things I know will happen. I have learned to lean into this with compassion meditation to accept the heaviness before the event, even though I don't know what or when. This seems to help me be clear headed, energetic and efficacious in the actual events.
I am just putting this out there as either hearsay or my subjective experience of my life, not as anything which could be a proof of any sort to anybody else.
The premonitions we receive from the future, while undoubtedly real, always seem to be quite fuzzy and garbled. Usually it's nothing more than a feeling; when in the form of a premonitory dream, it's communicated with vague imagery. In all cases it seems to be open to a great many possible interpretations, and it often seems that it doesn't make sense until the relevant event has been encountered.
This seems like it must be related to the QM principle that the correlation between entangled particles cannot be verified until they can be compared directly.
Most dreams are just processing daily experience. Precognitive dreams have quite a distinct feel to them, or at least, those who have experienced them (I am not among them) are quite adamant that this is so.
Wonder what you think of dreams as connecting future to present through quantum information represented through energy pathway
Nice article - and it's lovely to see the complexities of quantum correlations and entanglement being discussed.
I don't really agree that this physical system (with violation of the Bell Inequality (BI)) shows that either Alice's (or Bob's) measurement affects the results of measurements of Bob (or Alice).
If you look at this from the perspective of the reduced density matrix then Alice's measurement does not alter Bob's and vice versa.
You don't even need correlated particles to see a violation of the BI. It can be observed with a single particle. In the standard version of the BI with a spin-1/2 particle Alice and Bob will measure the spin at 3 angles, typically chosen at zero, 60 and 120 degrees. They'll choose these directions at random and record their results. When they compare notes later they will find a violation of the BI, if the particles are quantum correlated (eg a singlet state).
Now suppose Alice *prepares* a spin-1/2 particle, at random, in one of the six possible states chosen from the set (angle of measurement, up/down) and sends that on to Bob. Bob will do his random measurement thing as he would for a BI experiment. When they later compare notes there is a violation of the BI between Alice's preparation data and Bob's measurement data.
The key feature here is that violations of the BI are observed in joint *data* - lists of numbers - and the statistical properties observed in this data cannot be explained with a classical model of probability.
Together with a colleague, I published a paper on this and showed how it could be used as an alternative to using correlated particles for one form of quantum key distribution.
But it also has implications for what the BI is telling us. In essence, it harks back to Boole who showed that if you have 3 binary random variables with a joint distribution P(A,B,C) then the marginal joint probabilities like P(A,B), P(A,C) etc are constrained by an inequality. This is the BI. Boole, of course, was using a classical assumption that the variables 'existed' (had definite values) in an objective sense outside of measurement.
It is, as you pointed out, tied into complementarity and the downstream consequence of that which is the uncertainty principle.
It's my view that the BI is telling us about the property of realism, assumed by classical physics, and is not about the locality (i.e causality) aspect - but that's very much a non-standard view and I'm probably wrong on that score.
Particles are created in antimatter opposites. There are multiple mirror symmetries (charge, momentum, polarization, angular momentum etc.) comparing two particles that were created from photons or particle collisions. If 2 photons are created at some point in space such that nothing else affects their phase, polarization or whatever else you can measure on a photon, then those 2 photons leave each other in opposite directions, with mirror opposites of multiple types of measurements (spin orientation, momentum, whatever). Even one thousand light-years away, traveling through a perfect vacuum, they are mirror opposites in some measurement ( I don't have the expertise to describe the various types of measurement that can be done, though I do know quite a bit about it for a mechanical engineer). So why does *almost* everyone write that measuring one affects the other and not bring up the fact of mirror symmetries that can travel thousands of light years away from the starting point?
Everyone please respond to my answer. I rarely see people write about what I just described although I know it is out there. I would like to see others similarly curious about this and if people can describe it better than I can.
"Mirror symmetries that can travel thousands of light years away from the starting point..."
This was exactly what Einstein was proposing in 1935, and exactly what Bell (1964) demonstrated was an inadequate explanation. He demonstrated that there is no getting around the fact that what Alice does affects Bob's particle, whether she does it before or after Bob's measurement.
The proof is a little more technical than I want to get into, but Nick Herbert did the best job of making it accessible, in his book (Quantum Reality) or on this web page: https://www2.cruzio.com/~quanta/bell.html
My guess is that something in the initial assumptions of the proof is resulting in the (incorrect) spooky action at a distance conclusion. Can you put into words, better than I can, this assumption ?
Here is my attempt, please add your thoughts on the following paragraph:
The starting assumption, that all physical properties of a photon or particle are random in time, even when there is no measurment, is incorrect. Therefore, removing this starting assumption results in the fact that spooky action at a distance is incorrect. In reality, the production of 2 photons from a single point in space has physical properties (spin orientation, momentum, angular momentum etc.) dependent on the exact conditions (spin orientation, momentum, angular momentum etc.) of the "thing" that created the 2 photons. The two photons produced go off in different directions with mirror symmetry. There is no spooky action at a distance when some property is measured on one of the photons.
Why isn't this the answer or a slightly better worded version of it?
The conclusion is not dependent on anything about randomness in quantum mechanics. The conclusion is robust. The conclusion is that reality is connected and information travels both forward and backward in time.
This is a technical subject, and I've tried to make it as accessible as I know how. If you want to second-guess the physicists, start by understanding the proof. A good place to start is in Nick Herbert's book. https://www.amazon.com/dp/B005KDDTXM
My understanding of entanglement is that quantum superposition,
the fact that particles exist in multiple states at the *same* time,
is *absolutely* integral to entanglement. If superposition (i.e. multiple states existing at the same time) is wrong then entanglement is wrong.
https://www.astronomy.com/science/what-is-quantum-entanglement-a-physicist-explains-einsteins-spooky-action-at-a-distance/
Below is a cut-and-paste from the link above:
To truly understand the spookiness of quantum entanglement, it is important to first understand quantum superposition. Quantum superposition is the idea that particles exist in multiple states at once. When a measurement is performed, it is as if the particle selects one of the states in the superposition.
For example, many particles have an attribute called spin that is measured either as “up” or “down” for a given orientation of the analyzer. But until you measure the spin of a particle, it simultaneously exists in a superposition of spin up and spin down.
There is a probability attached to each state, and it is possible to predict the average outcome from many measurements. The likelihood of a single measurement being up or down depends on these probabilities, but is itself unpredictable.
Though very weird, the mathematics and a vast number of experiments have shown that quantum mechanics correctly describes physical reality.
The spookiness of quantum entanglement emerges from the reality of quantum superposition, and was clear to the founding fathers of quantum mechanics who developed the theory in the 1920s and 1930s.
To create entangled particles you essentially break a system into two, where the sum of the parts is known. For example, you can split a particle with spin of zero into two particles that necessarily will have opposite spins so that their sum is zero.
In 1935, Albert Einstein, Boris Podolsky and Nathan Rosen published a paper that describes a thought experiment designed to illustrate a seeming absurdity of quantum entanglement that challenged a foundational law of the universe.
A simplified version of this thought experiment, attributed to David Bohm, considers the decay of a particle called the pi meson. When this particle decays, it produces an electron and a positron that have opposite spin and are moving away from each other. Therefore, if the electron spin is measured to be up, then the measured spin of the positron could only be down, and vice versa. This is true even if the particles are billions of miles apart
The claim that "a vast number of experiments have shown that QM correctly describes physical reality" is also misleading. Yes, quantum theory has been used to understand many phenomena that were incomprehensible from classical mechanics. But I wouldn't say it "correctly describes physical reality". It's a useful model that enables us to compute some things well. But most quantum calculations are so difficult that we can't do them. We don't know what QM predicts in most circumstances of interest, so it is only in a few special cases that quantum theory can even be tested.
here is a pdf version of youngs double slit experiment that I wrote - slightly more details and easier to read than the other link I sent
https://zhydrogen.com/wp-content/uploads/2018/04/double-slit-4-18-2018.pdf
I assume I found your substack based on an article you wrote on LENR about 1 year ago. I'm a long time cold fusion follower and somewhat of a cold fusion scientist. I like your anti-aging website too - recently I've been reading about Advanced Glycation End Products (AGEs) and how to reduce them. I already drastically reduced my seed oil intake 2 years ago and eliminated most processed foods.
Just to make sure that you know, "a vast number of experiments have shown that QM correctly describes physical reality" is a cut-and-paste from the link that I mentioned - and I don't agree with it. I believe those people who write that quantum mechanics can be described in more classical terms. And you know the limitations of quantum theory as you just wrote. I think the limitations of quantum theory are so big and that the classical interpreation of atoms is *so* good that classical interpretations of the atom are more likely to be correct. I *have* studied the classical interpretation of the atom in my non-physics educated way. Namely I'm speaking of Randell Mills of Brilliant Light Power. If you look him up, disregard his energy invention and focus on his complete re-writing of quantum mechanics.
I have tried to educate people with my website that summarizes a tiny portion of Randell Mills' theory of the atom which can be found here:
https://zhydrogen.com/
And Randell Mills theory of that atom (and universe etc.) can be found here: https://brilliantlightpower.com/book/
note that I show an explanation for the Youngs double slit experiment (others have written the same explanation before I did) based on surface plasmon polaritons which can be found here
https://zhydrogen.com/?page_id=1760
An earlier 2005 paper that shows this same explanation for the double slit experiment is here:
Plasmon-Assisted Two-Slit Transmission: Young’s Experiment Revisited
H. F. Schouten, N. Kuzmin, G. Dubois, T. D. Visser, G. Gbur, P. F. A. Alkemade, H. Blok, G. W. ’t Hooft, D. Lenstra, and E. R. Eliel
Phys. Rev. Lett. 94, 053901 – Published 7 February 2005
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.94.053901
(I have a copy of the pdf above that I could send you if you email me)
I would disagree with some parts of this quote. Both superposition and entanglement are basic to quantum theory, but I wouldn't say that the two concepts are so closely related that you have to understand superposition before you can understand entanglement.
Entanglement = The probability functions in QM (the wave functions) apply not to individual particle positions but to entire configurations of many particles. There is a probability of a set of particles all being in particular places.
Superposition = These same wave functions can be added and subtracted in arbitrary combinations.
Both these concepts, entanglement and superposition, derive from the fundamental quantum concept that in general we can't know exactly what is where, but we're limited to describing the world in terms of these probability functions.
They are intimately connected. Entanglement arises as a consequence of superposition in a Hilbert space that is the tensor product of two Hilbert sub-spaces.
Ok I will try, in the meantime can someone else help me?
So fascinating!
It's easy to say "everything is connected to everything else", and we might shrug that off because it is true even in Newtonian physics. In Newtonian physics, it's true in the sense that every particle came from the Big Bang, and they all interacted and affected each other in the deep past.
Quantum physics is stranger than this PRECISELY BECAUSE IT IS MORE DEEPLY CONNECTED. Particles are certainly entangled in pairs, as we talk about in the context of Alice and Bob, and what Alice does over here affects Bob's particle over there. But this is just the most trivial case. Quantum physics says that entanglement is universal. If you pick up a solid piece of anything, then all the electrons in that solid are part of the same wave function, and they can't be treated, even approximately, as though they were independent particles. This is the most radical truth of QM.
In actual lab experiments, only nanoseconds before, but in principle it could be a long time in the past.
Yes, it is absolutely correlated to the distance between Alice and Bob. But there is no reason, in principle, why this distance cannot be large, and the two particles don't have to be moving at the speed of light, so the distance can be that much smaller, and still the time difference can be maintained.
I believe the most important part of this theory, are its implications in daily life.
As a Buddhist, I have been taught that the ultimate law is the law of cause and effect. It is inescapable.
Further, this causality stretches in all directions, and there are teachings concerning latent and manifest effects, present affecting both future and past , plus more. I am no scholar, this is just the surface.
More and more science is validating Buddhist teachings from 2500 years ago.
Interconnectedness of all life, and causality with retro causality point to a truly hopeful message in daily life.
Your actions, words and thoughts do affect the entire universe, and each person can affect reality, not only for themselves , but also for others.
The karmic connections with those closest to you enhance this effect, but what really matters is your intention, irrespective of your theoretical knowledge.
So, although through past intentions (spanning eternity, not just this lifetime) you may accumulate a set of effects, considered as 'destiny', you are truly able to change this set, by new intentions.
That is real hope. And of course true responsibility.
Finally, this interconnectedness with all life suggests that a single life entity may affect the entire universe, and this means, as my mentor put it, that an inner change in a single human being, can change the destiny of the entire human kind.
please forgive my long comment.
Components of the angular momentum, or "spin" in two different planes. (Actually, there are 3 different planes, all mutually complementary. If you know the spin in the xy plane, you lose all information about spin in the xz plane and also the yz plane.