Sunday, August 24, 2014

If Schroedinger's Cat Enters The Forest, & No One Is Around To Observe It, Is The Future A Porkchop?

By Benjamin New



I often find myself thinking about the nature of the time space bubble we find ourselves in.
Perhaps you do as well. Certainly this is the primary function of the science of physics...to study the nature...of nature.
  According to the Copenhagen interpretation of quantum humor, the state of your reaction to my jokes is undefined until you observe them written here. Then you collapse into either one of the two humor eigenstates: either rolling on the floor laughing or frowning and groaning. There are a few assumptions being made on my part here, basically that my dear readers have a working familiarity with the basics of Quantum Mechanics. Fear not if you don't think you do! Here are a few links that will do the trick...if for instance you think that "the collapse of the wave function" is a condition over advertised by pharmaceutical companies that's cured with a blue pill, or if you think "discrete position and momentum" might be an illustration in some new sort of hipster Kama Sutra (Oh come on now. obviously sex is a semi-classical process---the quantum corrections are WAY too small to matter!),  then click this link to clarify things in regards to the rest of this article.

IF A TREE FALLS IN THE FOREST,
AND NO ONE IS THERE TO OBSERVE IT,
DO THE OTHER TREES LAUGH AT IT?



Quantum Mechanics is the most battle-tested theory in all of science. And one-third of our economy involves products designed using it. The device you are reading this on is directly a result of quantum mechanics. The principles of Q. M. work for conducting fundamental science as well as for very for practical applications. Some folks suggest that is all we need to know...it works...why question a good thing? However, this consistently dependable and useful physics model absolutely challenges any reasonable worldviews as it either denies the existence of a physically real world independent of its observation... or it suggests an unimaginable infinitely unfolding series of worlds forming from every possible event that takes place. Today friends, we are going to concern ourselves with the two most widely accepted views regarding the interpretation of quantum mechanics. The Copenhagen Interpretation, and the Many Worlds interpretation.

Copenhagen comes down to this: “everything we can measure ultimately behaves like a quantum wave, but this doesn't apply to me, so what are the implications of that?”
Many Worlds boils down to saying: “everything we measure ultimately behaves like a quantum wave, what are the implications of that?” The Copenhagen interpretation says what it says and it clearly does not  have apodictic dents in it's armor. It has no internal inconsistencies and it is not in contradiction at all with any observation done as of today...but the same can be said of Everett's Many Worlds interpretation.



Copenhagen is considered the standard model while Many Worlds has steadily gained in acceptance.

What we know is that particles are in fact in a state of superposition, that is to say that there is empirical evidence that simultaneous states co-exist in matter. Where paradoxes seem to occur are when we try to understand why or how. These undefined superpositions have been observed in larger quantum systems as well...and this is where the rub comes into play. Laws of physics as we understand them don't have exceptions. Gravity exerts force on galaxies, planets, bowling balls, beads, or molecules in a predictable and identical manner. Events in our macroscopic world all seem to have a causality. It's when we try to comprehend what our observations of very small particles means in the macroscopic world that we run into what seems to be contradictions with what we think we know of this objective world we are accustomed to. However it may well be that these paradoxes only exist in our brains. In other words, these paradoxes are only conflicts between reality and our feelings about what reality ought to be as opposed to what it actually is. As a physicist, one seeks to understand the nature of the physical universe, many physicists would rather stick to the mathematical calculations that represent physical reality and leave the interpretations and implications out of the picture.

( Professor Stephen Hawking and probably most physicists would rather not concern themselves with the interpretations, while Einstein, Heisenberg, Bohr, & others, certainly did. They discussed the possible philosophical implications as well as the physical implications ). There is an implicit ontology that no one really wants to discuss but everyone ponders when it comes to quantum mechanics.

HEISENBERG PROBABLY RULES


As far as can be tested, the Copenhagen model works, but comes at a price that Einstein & Schrodinger suspected was too high. And that price is acausal randomness and the implication that there is ultimately no objective reality. Our Newtonian reality intuitively does not seem to be that way. (Yet it probably is).  As Einstein said "the moon is not there if you don't look at it"...though he was being sarcastic...it is applying principles observed in the micro system to the macro system.
one of  the  key concepts of C.I is the wave function collapse. The idea that every event exists as a “wave function” which contains every possible outcome of that event, which “collapses”—becoming an actual outcome, once it is observed. A thought experiment that illustrates this (similar to Schrodinger's Cat) is if a room is unobserved, anything and everything that could possibly be in that room exists in “quantum superposition”—an indeterminate state, full of every possibility, until someone enters the room and observes it, thereby collapsing the wave function and solidifying the reality. The problem with this is that observation is given some sort of vaguely defined superpower in a way. It seems to suggest that we are somehow 'different' than the quantum systems we observe or outside of them...and I'm not sure I find that entirely feasible. Though as Niels Bohr, the father of the orthodox 'Copenhagen Interpretation' of quantum physics once said, "Anyone who is not shocked by quantum theory has not understood it". Some people have come to the conclusion that consciousness itself and particle physics are inter-related. There was a legitimate paper on this in 1997 by Dr. Henry Stapp at the University of California in which he suggested that the synapses in your brain are so small that quantum effects are occurring. He suggested that there is quantum uncertainty about whether a neuron will fire or not - and this degree of freedom that nature has, allows for the interaction of mind and matter. (I'll just say that this really doesn't seem intuitively correct to me, but that is just my opinion...and in the realm of QM, intuitions based on experiences in the classical or Newtonian world can't be taken all that seriously it seems). He's written several books on the subject and he is a quantum physicist who worked with both Wolfgang Pauli and Werner Heisenberg. (unfortunately this sort of suggestion has given rise to all sorts of ludicrous quackery...which is clearly NOT related legitimately to QM....for instance NO legitimate science claims the result of the cat in the quantum box can be manipulated by wishful thinking...there's a ton of new-age quantum quackery proliferating out there on the web, avoid it if possible... except for a laugh.)  I have a problem with this interpretation actually, it does not strike me as consistent or reasonable within what we know of nature...even at the quantum level. A law of physics should apply across the board...if there is an exception, this would be a first. I mean to say that the Newtonian world we are used to interacting in isn't and shouldn't be separate in terms of physical laws from the quantum world. Rather isn't it more likely that everything is a quantum system, every combination of particles, a quantum machine of sorts... including ourselves? Even the entire universe....a quantum machine.
This is why I tend to think that Hugh Everett's Many Worlds interpretation is, well,....less wrong. 

NOT ONLY IS FREE WILL AN ILLUSION,

BUT IT'S ALSO IRRELEVANT


Welcome to Many Worlds!
Many Worlds was proposed by Hugh Everett in 1957. Essentially it states that there is no wave collapse, but when we observe something the universe splits or branches off into an alternate timeline or world so to speak. 
Max Tegmark, the well known and respected astrophysicist says this about Everett's theory:  
"Everett’s theory is simple to state but has complex consequences, including parallel universes. The theory can be summed up by saying that the Schrödinger equation applies at all times; in other words, that the wavefunction of the Universe never collapses. That's it - no mention of parallel universes or splitting worlds, which are implications of the theory rather than postulates. His brilliant insight was that this collapse-free quantum theory is, in fact, consistent with observation."  We have observed larger and larger objects that can be in multiple states, using the same double slit experiment or variations of it.  The same wave-particle duality was exhibited on a molecule which had fully 108 atoms, made up of 2,424 protons, neutrons, and electrons.  The entire molecule (actually, thousands of them) interfered with itself, demonstrating that it was in multiple states. It seems that everything that can indeed be tested has demonstrated quantum superposition, so why not just extend that to “everything obeys the same quantum mechanical laws, including superposition.”? This is the essence and indeed the beauty of Everett's interpretation. It applies to everything. The math is elegant. It makes logical sense, requires no particular special provisions, no dividing the universe into an indeterministic microscopic world and the deterministic macroscopic world. Many would say no, “the physics at small scales is just different!”.  Maybe so...but as I've stated earlier there are no physical laws that work differently on different scales.  In our experience, the same physical laws (see the Navier-Stokes equation) govern everything.
Generally, in science,  all laws apply at all scales, it’s just a question of degree.  Relativity is at work at all velocities, you just do not notice the effects until you move really fast. Should this “size argument” (that larger objects somehow have different laws) turn out to be true, it will be the very first instance of such a thing. The quantum world builds the classical world. Everything in the classical, macroscopic world is composed of microscopic particles acting in unison.

The problem is, if it's a problem at all; the consequences of not collapsing the wave function is that the universe is constantly splitting into alternate worlds which accommodate each possible outcome of every single event. It's likely that for many years before Everett wrote his paper, people had thought about this problem, but Everett was the first to propose a logically consistent way of removing the barrier backed up by convincing equations to support it. Schrödinger had said a few years before in Dublin in a physics conference a few years before Everett published his paper that physicists fear that if we don't have the collapse, "We should find our surroundings rapidly turning into a quagmire, or sort of featureless jelly or plasma, all contours becoming blurred, we ourselves probably becoming jellyfish."
  In other words if there is no collapse, then all these possibilities are going to start propagating all over the place, and there won't be any cause or effect anymore. We,our selves, our physical beings, being quantum systems, become duplicated, and every possible position that a human body can be in will suddenly exist in classical reality. Schrödinger looked at that and booted the idea...the implications being too mind boggling for even a quantum physicist. Even a "mystical" explanation that makes no logical sense seemed better than that to him...and many others!

SYNCHRONICITY IN THE AGE OF INFORMATION

Everett who was very much a realist simply could not accept that consciousness was "privileged," or that the universe would not exist without it. He assumed human consciousness is a quantum-mechanical system like any other quantum-mechanical system. Everett had an advantage the earlier theorists didn't though. Information theory. We have called tthe era in which we live the Information Age...do you know why? We entered the Information Age in 1948 thanks largely to Norbert Wiener (the father of cybernetics) & Claude Shannon,  Shannon and Wiener proposed remarkable theories that said that information actually has a physical reality that is independent of any kind of meaning that you might want to give it. (Which is synchronous with observations made in QM).  The development of understanding information itself as a physical thing has given birth literally to all modern technology including the internet . Well, Everett began to calculate using information theory, which had just been invented. He developed a mathematical argument showing how data correlates within itself. Which is what happens in a superposition. essentially he showed that The Schrödinger equation never ends, including in the classical world. In Everett's theory, what happens is that when a human actually looks at a clock or any other object, he or she splits like an amoeba. (In his view, the observation interaction, is just an exchanging of energy. (A person looking at the clock, in our example, is an energetic interaction, with photons of light bouncing off the clock and going into the person's eye.) According to Everett's view, when the human correlates him-herself, (interacts or exchanges energy with the clock or whatever is interacted with) then he-she splits into copies of him- herself, one for each element in the superposition. This split creates the 'many worlds'. As bizarre as this sounds—a person splitting into numerous copies of him-herself...Everett's theory has stood the test of time and peer review. It has not been shown to be mathematically incorrect. And to be sure, people have tried very hard. They have found some minor mathematical gaps, but no one has been able fault the basic mathematical logic, which has made a very convincing case that every time there is an interaction anywhere in the universe, one of the systems splits in order to accommodate all of the elements or superpositions that are contained in the wave function that describes the observed system. So the basis for having multiple universes emerges from this solution to the measurement problem in QM. The universal wave function of Everett's theory ultimately describes a series of branching universes that make up what David Deutsch has called the "multiverse," and recent discoveries in Astrophysics as well as in Neuroscience hint at this as well. (Hence the idea of titling  this section "synchronicity") In these branching universes, there are many trillions of copies of you, of your neighbor, of Everett. There are branches in which Everett is still alive, others where he died at birth. Everything that is physically possible happens in some branch of the multiverse.
The implications of this are nothing less than astonishing.
There is no ceiling of improbability, other than the laws of physics which may actually operate differently in other universes. Whatever could possibly occur does. So when  you are confronted with circumstances that appear to be impossible, like a missing woman unknowingly standing in the background of a photo being taken of her family for a newspaper story about her own disappearance,  remember that nothing is impossible on a large enough scale—indeed, given an infinite number of chances, literally anything you can imagine is not only possible, but inevitable.

IT IS AND IT ISN'T

Consider what we know about how probability works
In a Multiverse; on a persoanl level, the implications become somewhat overwhelming.
There are trillions of versions of you—all of which are undeniably you—but many of which are very, very different from the “you” of this world-line. The differences between the various versions of you are as vast as your imagination can allow...or more. There’s a world-line where you’re the worst dictator ever and an architect of genocide. Conversely, there’s another where you dedicate yourself to world peace. Your crappy  band in high school became the dominant musical force on the planet, somewhere. Ladies, in one timeline Johnny Depp is your lover. Men can find some solace in knowing that they are sleeping with Scarlett Johansson in at least one of these timelines..though conversely perhaps in another they are married to their former cell mate Bubba or a blow up doll. Well, you get the idea. Multiplicity might explain a lot of things...feelings of deja vu,  a close connection with someone you’ve never actually met,  the sense of synchronicity itself. Perhaps there is some type of resonance or distant memory of a previous timeline that explains this. Think of  Buddhism or Hinduism in a divergent light for a moment. Both suggest a reincarnation. They posit that we manifest physically on Earth multiple times, and that we can learn from our past and future “paths”. Indulge me for a moment but might these belief systems be an intuitive understanding of the Multiverse idea? ( I'm thinking about the previous assertion that you were, or are; an evil mass murdering dictator in one timeline... it can be comforting to know that the experience of all possible facets of human nature is explicitly required  for growth which is the case in those belief systems).

This is not to suggest you should kill people or engage in any other immoral behaviors mind you, but the alleged purpose of this cycle of learning is to eventually learn all that there is to learn, to actually transcend physical existence. Of course you dear reader are highly evolved and learned many lifetimes (world-lines) ago all there was to learn from indulging the dark side of human nature.

Of course you did! While some folks seem to believe that our destination is some type of eventual meta-godhood, where we are thrown from our carriages off of the great Ferris Wheel Of Karma or preside over a universe of our own creation... others believe that the cycle just simply repeats. If the whole thing runs down, plays out, or heat death ends all realities; perhaps the cycle is simply restarts and the next Multiverse begins. Perhaps this has already been happening trillions of times? Wiz Bang, expansion, contraction, collapse, Wiz Bang again! Bazoomy! Off we go! As Johnny Carson used to say "I'll be right back"!
...And perhaps he will.

DANCING DANGEROUSLY CLOSE TO THE QUANTUM WOO PRECIPICE

(But Not falling From Grace)


  In this Multiverse model with its infinite world-lines, you have existed before. In fact, all the infinite versions of you have existed before, and will exist again and again.  The same goes for Kurt Vonnegut, Billy the Kid, Thomas Jefferson, Jimi Hendrix, and Attila the Hun... along with every possible idea, creation and situation throughout all of our past and future, across all realities.
Of course you know if everything that exists or will exist has already existed there is nothing new and nothing original. Not exactly a concept that hasn't been touched on before.


  • From a 19th Century BC Egyptian poem: "What has been said has been said."
  • From The Old Testament : "It has all been done before; there is nothing new under the sun."
  • From The Beatles "All You Need Is Love": "There's nothing you can do that can't be done."
  • From John Steinbeck :"There are as many worlds as there are kinds of days"


Many writers, artists, and musicians (myself included on occasion) describe a sense that the pieces we craft are in some manner already existing, fully formed, merely waiting for us to come along and excavate them like fossils in some ethereal tar pit.  In an infinite Multiverse, there is a possibility this may be exactly what the pieces are. Creation and interacting with art is a very unique human experience. There are aspects of the human condition that are difficult or impossible to communicate by any other means. (Often physicists too say their ideas occur fully formed in dreams...and that language simply does not exist to express them adequately.)  This quality has been ascribed to the observations of QM, especially the "observe" portion of the Copenhagen Interpretation...an observation is kind of an interaction of any kind and it's said that there is no known language to properly describe this). While it is not possible to accurately describe in any language what love is, or what it feels like,  there are plenty of ways to communicate this in art. Most often it is through artistic expressions that resonate with us  that many of us develop our first notions of the nature of love or other complex human experiences that elude description in other forms of communication.

I am reminded of the lyrics in the Who's song "905"
from the Who's album  "Who Are You" written by John Entwistle:

"...Now I'm to begin
The life that I'm assigned
A life that's been used before
A thousand times

I have a feeling deep inside
That something is missing
It's a feeling in my soul
And I can't help wishing

That one day I'll discover
That we're living a lie
And I'll tell the whole world
The reason why

But, until then, all I know is what I need to know
And everything I do's been done before
Every idea in my head
Someone else has said
At each end of my life is an open door"

SUMMARY

While there are actually many interpretations of QM, the two most accepted are the Copenhagen and the Many Worlds...most others are tweaks on these two and are pretty much just variations on the two main ideas. There are however others that are different:

Pilot Waves, Hidden Variables and the Implicate Order


David Bohm (1917-1992) came up with an elegant but more complicated theory to explain the same set of phenomena (normally, more complicated theories are disqualified by the principle known as Ockham's Razor). Bohm's theory follows original insights by Prince Louis de Broglie (1892-1987), who first studied the wave-like properties of particles in 1924. De Broglie suggested that, in addition to the normal wavefunction of the Copenhagen Interpretation, there is a second wave that determines a precise position for the particle at any particular time. In this theory, there is some 'hidden variable' that determines the precise position of the photon.  John von Neumann (1903-1957) wrote a paper in 1932 claiming that this theory was impossible. Von Neumann was such a math wiz that nobody actually bothered to check his calculations until 1966, when John Bell (1928-1990) proved he'd bungled it and VIOLA! ...there could actually be hidden variables after all ... but only if particles could communicate faster than light (this is called 'nonlocality' in physics). In 1982 Alain Aspect demonstrated that this superluminal signaling did appear to exist, but then David Mermin came along and showed that you could not actually signal anything. There is still some argument about whether this means much of anything.
Bohm's theory was that this second wave was indeed faster than light, and instantly permeated the entire universe, acting as a guide for the movement of the photon. He called it a 'pilot wave'.
Although this theory explains the paradoxes of quantum physics, it also introduces a new faster-than-light wave and some hidden mechanism for deciding where it goes to create an 'implicate order'. That's quite a lot of luggage to carry and science generally likes to travel light. Worse still, Bohm  become something of a mystic, identifying his 'implicate order' with Eastern spirituality. It's all very interesting and we should keep in mind that "many worlds" was not broadly accepted at first...in fact it was more or less ridiculed...at least privately. 

Consistent Histories 

This interpretation analyzes sequences of states of a system (which may or may not include the whole universe), to find what questions can be consistently answered about the system, such as “was the particle at A or B at time T?” The measurement problem, however, is not resolved: the question of which histories actually happen remains a matter of probabilities just as with the standard Copenhagen approach...so I guess it's really just a variant on Copenhagen.

Shut Up and Calculate!
David Mermin said in a lecture" If I were forced to sum up in one sentence what the Copenhagen interpretation says to me, it would be 'Shut up and calculate!"Some physicists talk of the “shut up and calculate interpretation” which is to ignore the philosophical puzzle of how the classical and the quantum coexist entirely.

Transactional Interpretation

This interpretation was proposed by John G. Cramer in 1986 and it has waves traveling forward and backward in time, setting up standing waves between an emitter of a particle and its detector.

Other Odd Considerations


Although not technically an interpretation of QM, there are some other theories related to it that frankly...give me a headache. Largely because they seem so far fetched yet undeniably plausible at the same time. One of these would be that the superposition is observed because we are actually in a computer simulation. When you open a simulation what happens? The various components of the simulation are in an undetermined state and then software tells them to form a certain way to create the simulation. It does explain the wave collapse doesn't it?  Far fetched? Certainly...wait...maybe not. After all if our technology were sufficiently advanced enough to actually simulate a universe, we likely would. If we could simulate one...why not another? Or many? ...all existing right next to each other. An advanced civilization could likely do such a thing...geez maybe even our ancestors were that advanced and are doing it right now! Maybe we are actually simulations of their ancestors in some computer somewhere. We currently actually have supercomputers performing lattice quantum chromodynamics calculations which essentially divide space-time into a four-dimensional grid which then allows researchers to examine what we call the strong force, one of the four fundamental forces of nature and the one that binds  quarks and gluons together into neutrons and protons at the core of atoms. Martin Savage, from Washington University has said “If you make the simulations big enough, something like our universe should emerge", and by studying that, we could then look for a “signature” in our universe that has an analog in the current small-scale simulations. We can test this.
Savage and colleagues Silas Beane and Zohreh Davoudi, a UW physics graduate student, suggest that this signature could show up as a limitation in the energy of cosmic rays. At any rate suffice it to say some very intelligent and learned scholars do not find this notion ridiculous.
Then there's the idea that the universe is a hologram.  Leonard Suskind and other highly respected physicists posit this idea...watch this video...

 
 
So, I know what you are saying right now..."what's the bottom line on this stuff, what happens to Schrodinger's Cat? "

In Copenhagen: The cat's dead and alive simultaneously until you look at it..then it's one or the other.
In Many Worlds: The cat's dead in one world, alive in another.
In Pilot Waves, Hidden Variables and the Implicate Order: It's either dead or alive, of course! (But becomes a Buddhist monk.)
In Consistent Histories: Don't ask, don't tell.
In Shut Up And Calculate: No one cares about the cat.
In Transactional: The cat is both alive and dead but it's in the past as well as the future simultaneously.
In a computer simulation: The cat's a cartoon...but so are you!
In a hologram: The cat's a 3D cartoon and the future is indeed now a pork chop.

POSTSCRIPT

In 1957, when Everett's thesis was published in Reviews of Modern Physics, the editor of that issue was Bryce DeWitt. Initially, DeWitt was unimpressed with Everett's theory. He wrote to Everett and asked "if the universe is splitting, then why don't I feel myself split?"
Everett responded. "Well, Copernicus made the analysis that the Earth was moving around the sun, undoing thousands of years of belief that the sun was going around the Earth, and people asked him, If the Earth is moving around the sun, then why don't I feel the Earth move?"
 DeWitt, who was well aware of the Newtonian reasons why they wouldn't, simply said "Touché".

In the late 1960s,  DeWitt when he was working seriously in quantum cosmology, DeWitt was attracted to the universal wave function as an interpretive method of dealing with what was going on, and he started writing about it. In 1970, he published an article in Physics Today that set off a firestorm of letters back and forth in that publication, debating the theory. Then, in 1973, he went to Everett, and said, "I know that there's a longer version of your thesis than the one that I printed in 1957. I'd like to publish it." The full dissertation was  137 pages, while the thesis that was published in 1957 was only about nine pages. [You can read the full dissertation here if you like.]
Apparently John Wheeler  (Noted physicist who worked with Bohr) was a professor at Princeton University, and was influential in mentoring a generation of physicists who made notable contributions to quantum mechanics and gravitation including Everett, anyway he had cut three quarters of Everett's original thesis. Wheeler is said to have had a dream that Bohr was somehow going to approve it, so he made Everett remove his direct attacks on the Copenhagen Interpretation as well as his provocative metaphors about splitting observers like amoebas, and bifurcating cannonballs. (as well as, for some unknown reason, a whole chapter on information and probability theory).
  As a result, a lot of the explanation for things that people saw as weaknesses in Everett's theory were cut out of the version that people read.  In 1973, DeWitt published the long version, along with the short version and some other papers, including one by himself, in a book called The Many Worlds Interpretation of Quantum Mechanics. He used the phrase "many worlds," because he thought it would be provocative and catchy, it was! And the name stuck. Incidentally, Hugh Everett did not call his theory "Many Worlds"...he called it "The Relative-State Formulation of Quantum Mechanics."

If you have read all this material and the links, congratulations! You are now a certifiable quantum mechanic! Send me the 1200 dollars and I'll print you out a certificate with a 3 dimensional hologram of a cat in a box eating a pork chop ! 

Of course, no electrons were harmed in the making of this blog.


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