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"So, the Universe is not quite as you thought it was?  You'd better rearrange your beliefs then, because you certainly can't rearrange the Universe!"

-Isaac Asimov

Quantum Mechanics & Consciousness

5/31/2017

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Yup, we're going there
What Am I Even Talking About?
    I love quantum mechanics and always have done.  You might not have guessed it though, because I don't talk about it much online.  There are two good reasons: 1) Once I get started I won’t be able to stop.  2) It’s too big to trivialise with a 5-minute youtube video or an Instagram post.  It would be like trying to sum up the rise and fall of the Roman empire in a single hashtag. #Greedfollowedbycorruption
    Quantum mechanics is probably the most important discovery since evolution.  More fundamental than relativity, more shocking than the Big Bang Model.  It is the framework we rest modern Science on and it’s gosh-darned fascinating.
    What I really want to talk about today is "quantum spirituality".  You may have come across it.  If not, go to Instagram/twitter etc. and type in any of the following terms: quantum, quantum theory, quantum physics or quantum mechanics.  What you'll find are associations with Buddhism, Hinduism, vegetarianism, yoga, mysticism, alternative medicine, cannabis, crystal healing,  left-wing politics, exercise, healthy eating, positive mindsets and, more than anything else, “consciousness.”  Now, let me be clear just so nobody thinks I'm attacking them:

1) Consciousness has played a part in quantum mechanical theory.
2) We'll get to that bit shortly.
3) I think it's good to talk about the human mind and its potential.
4) I’m not against philosophical discussion at all.

   
    I also know why a lot of people associate these things with quantum mechanics.  It’s down to one person (who we’ll get to shortly) but, and I'm afraid this is crunch point - some of this stuff isn’t anything to do with quantum mechanics.  Even remotely.
    Please understand my intentions.  I don’t want to dismiss anybody’s opinion about the meaning of life.  I’ve got no business doing that.  But as a Science educator, it is my business to make sure people have a good understanding of quantum mechanics.  So strap yourselves in folks, we're going to get it right.
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Dear quantum spiritualists
Why do I have to ruin it?
    I probably sound like the kid who tells all the others that Santa Claus isn’t real.  Can’t I just let people go on believing in Santa Claus?  I appreciate that point of view, but if I may offer a counter-argument? 
    Believing in Santa is comforting and fun but when you learn the truth, that your loving parents have gone to the trouble of getting you Christmas presents, haven’t you learned something better?  Yes it can be painful to let go of cherished beliefs but surely it’s better to know the truth than a lie, no matter how self-comforting that lie is.
    I want to educate people because the real quantum mechanics is so much bigger and cooler than what you’ve probably been told.  You might think quantum spirituality is interesting, but trust me, you ain’t seen nothing yet. 
    I also think it’s important to get Science right because a lack of education can be dangerous.  To quote Professor Hawking: "the greatest enemy of knowledge is not ignorance, it is the illusion of knowledge".  The point he's making is that it's very hard to teach someone if they think they already know everything.  Teaching quantum mechanics is difficult (trust me) but it's even harder when people have a crooked version of it in their heads already.  Frankly, I think people deserve the truth.  You wouldn't accept a substitue diamond ring, so why accept a substitue version?
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Just ask John Lennon, Paul McCartney, George Harrison and Ringo Star
Defining Words Differently?
    Let me ask you something.  When you looked at the above photograph and saw the caption underneath, did you think: "He's got the wrong band there" or maybe "he's telling some kind of joke"?  Well, it's actually neither.  I wasn't making a joke and I'm not getting confused.  That's a picture of The Beatles.  I'm serious.  I believe that's a picture of The Beatles and you have no right to tell me any different.  You can probably see where I'm going with this.
    Imagine you’re a Beatles fan.  One day you go online and search The Beatles.  You find someone else saying how much they love the Beatles, except the band they’re posting pictures of aren’t the Beatles.  It’s Nickelback.
    It’s a bit puzzling but everybody makes mistakes sometimes!  So, you message the person not trying to be critical, saying “hey there pal, I think you might have uploaded the wrong picture by accident!”  But, rather than going “whoops, cheers dude” this person responds with “yeah, well it’s my blog and I’ll post what I want!” 
    The next day another person does the same thing, labelling another picture of Nickelback as "The Beatles".  So you ask them if they want to learn a little Beatles history.  They say yes, but then about 30 seconds later they start saying “well that’s just your definition of the Beatles, I define it differently”.  
    Now imagine you youtube your favourite Beatles song but instead of Eleanor Rigby you get that infuriating “How you remind me” mis-labelled as The Beatles.  Then people start posting pictures of Iron Maiden and labelling it The Beatles.  And then pictures of the Metallica as The Beatles. 
     You don’t mind these bands at all, they’re fine.  But they aren’t the Beatles.  The problem is that every time you talk to someone about it they accuse you of being picky, or petty, or narrow-minded, or a hater.  Then it gets ludicrous. 
    People start posting pictures of their salads with “The Beatles” attached to it.  You even see people offering courses and workshops on Beatles history...courses which make no mention of instruments, John Lennon or even Liverpool.
    It seems that for some people, truth really isn't a high priority and they go with the ever popular "I can define my own truth however I want" response.  Shouldn't I just let people use their own words?  Why do I have to challenge them on it?  Doesn't that make me a trouble-maker looking for a fight?
    Well, imagine if I started posting racist terminology on my page but then said "yeah, well I define those words differently", how well do you think that would fly? 

Or if I started posting pictures of dairy and meat products with #veganlifestyle. 
Or if some money-loving oil corporation started posting #Namaste on its home page. 
Or if some fundamentalist hate group started posting #raise your vibration while they campaigned against gay marriage. 
Or what if someone starting hitting people and saying "yeah well in my version of reality, they don't feel  pain so leave me alone and let me live me own life!  #peacefulprotest" 

    Would you be OK with that?.  Surely you’d want to educate people on what those terms really meant.  You're not doing it to be a hater, you're doing it because you respect the human intellect and think people should be challenged when they are wrong, right?  So, to be clear, I'm not here to attack you, I'm here to spread knowledge.
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#Godzilla
Quantum Mechanics in Basic Terms
     Quantum mechanics is a nuanced theory.  You have to be careful what you say because it can easily mean the wrong thing.  It’s also a vast theory.  QM doesn’t refer to just one idea but a whole collection of theories, hypotheses, predictions, experiments and conclusions which form a framework for us to work in.  Nobody can honestly claim to be familiar with the entire breadth of the theory.  And, on top of that, it's very mathematical in nature. 
    I had to attend several math classes at University in order to make sense of what was going on in my QM classes.  Now, as I’ve said before, anything you can say with equations you can say in words, but it takes a huge amount of time to do so and that gives you two options.
    Either you take a long time to get things exactly right, during which people get bored, or you cheat and use analogies and simplifications.  The explanations become sort of casual, hand-waving shorthand, which is about 90% correct but misconceptions can arise as a result. 
    It’s not because you want to be snobbish or deceitful and it’s certainly not because you don’t respect them.  Everybody is clever enough to understand Science.  But it can take time without maths.  The ultimate goal is to get people to understand the beauty of the theory, so it’s better to explain “the gist” so they understand what the fuss is about. 
     You can imagine the mess that ensues.  It’s a perfect storm of a nuanced theory which has lots of aspects, being explained in simplified ways.  It’s in these poorly understood realms that pseudoscience can creep in.  Perfectly intelligent people can believe things which aren’t true because it’s hard to tell Science from pseudoscience and it’s the cheap knock-offs which are trying to fool you.  You have to be wary of quantum con-artists.  Be smarter.   
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If it doesn't contain this equation, it's not real quantum mechanics.

The Measurement Problem
    We’re going to pin things right down and focus on one aspect of quantum mechanics which gives rise to all the discussion about consciousness and spirituality.  And the best analogy I can think of is Toy Story.  Yes, I'm using an analogy...even after what I said a moment ago.  But we're going to tread carefully and I'll point out the limitations and strengths of the analogy in the discussion.
    Imagine you place your favourite Buzz Lightyear doll on your bed and leave the room for a moment.  Then, when you come back, it's somehow on the shelf.  You pick it up, shake it a bit and put it back.  Then, when you come back later in the afternoon, it's outside in the garden.  This doesn't make sense at all, so you decide to do some measurements. 
    Every hour you place it on your bed and then walk away.  Each time you come back it's in a slightly different place.  90% of the time it's still on the bed, 8% of the time it's on the floor or shelf and 2% of the time it's outside in the garden.  There is only one logical explanation, as strange as it sounds: the toy is only a toy when it's being observed. 
    When you look away from it, it somehow adopts other characteristics (being alive).  You can predict the probability of where it's going to end up when you finally look, but you can never be exactly sure.  Ultimately, you need two sets of laws to describe the behaviour of the toy.  One for when it's being an inanimate piece of plastic and another for when you're not looking and you can only measure it's probable behaviour.   
    This, in a nutshell, is what particles do.  It's called “the measurement problem” for obvious reasons.  Measuring the particle/toy forces it to behave normally but whenever we stop looking, it does something different and we lose our ability to predict its behaviour.  I've been working on this blog for weeks and it was only just now that I hit upon the Toy Story analogy.  Well, it was either that or these things...
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"Call me space-ranger one more time, I dare you!"
The Copenhagen Interpretation
   
Explaining the measurement problem has been an important part of quantum mechanical theory for decades and there are many different ways of doing it.  The one which is most relevant to our discussion is called The Copenhagen Interpretation, postulated in the city of Copenhagen by Niels Bohr, Werner Heisenberg and Wolfgang Pauli.  This is by no means “the correct” explanation but it is a way to make sense of things.
    Imagine you've not seen Toy Story and all you know is that your toy somehow appears in different places.  What explanation would you propose?  The Copenhagen proposal is that a particle given a choice will choose all options until observed.  If the choice is about where to be, it will exist in all possible locations.  If the choise is about what energy to have, it will adopt all possible energies.  But when it is observed it crystallises into one state.  That final state could have been impossible when it was acting as an ordinary particle, but since we gave it free reign it was allowed to explore every possible state and adopt one it otherwise couldn’t have.
    Just like the toy which suddenly appears in the garden.  Copenhagen says that Buzz Lightyear existed at every point in the house and garden, but when it was observed, it snapped into one location...90% of the time that's back on the bed but every once in a while it turns up somehwere seemingly impossible.
    We call the list of possible states the particle could be in “the wavefunction” (there are other ways of defining the word wavefunction but they all amount to the same thing).  The wavefunction is spread across many different states but when you take a measurement, it “collapses” into just one. 
    This raises all sorts of questions, the most obvious being: why does observation trigger wavefunction collapse?  It’s as if the particle somehow “knows” it is being watched.  In our Toy Story analogy this seems fine because the toys are thinking beings and they know to "play dead" when Andy comes into the room.  But how does a single electron know to collapse into one place?
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No jokes, this is just a really useful diagram!

Consciousness Enters the Discussion
    If you've ever watched Toy Story and wondered what the rules are, quantum physicists do the same thing.  If we set up a camera in Andy's bedroom, would the toys come to life?  Can the toys choose to enter their toy-state?  What if they're being watched from behind and they don't know about it?  Why do they stay in their live-state when another toy observes them?  Why does the dog Buster not count?  What about an artificially intelligent robot?  Would a chimpanzee trigger a collapse?  Can babies see them moving?  What about that bit when Sid sees Woody talking? 
    Believe it or not, quantum physicists have to ask very similar questions about particles.  If we sit a camera on our particle and watch a video feed, will the wavefunction collapse?  If we put the camera there but nobody is watching it, does that count?  What if we record it on a video disc and never look at it?  And if observation is involved, is it the eyes, the brain, the memory?  What's going on?  There are no easy answers.    
    The first attempt at seriously tackling the question was made by the brilliant physicist John Von Neumann.  In 1932, von Neumann wrote the first definitive textbook on quantum mechanics, formalising all the known laws under one framework.  One chapter in particular deals with the measurement problem and in it, Von Neumann works mathematically outwards from the particle to find out what causes it to collapse.
    He concluded that the “choice” part of an experiment (ie when the particle can choose which state/location to be in) doesn’t trigger a change and the particle remains “uncollapsed” after the choice has been offered.  He then showed that the detector/equipment of the experiment was also not the point at which the wavefunction collapsed.
    In fact, Von Neumann showed there was no obvious place which could be triggering wavefunction collapse.  Anything he included in the calculation was insufficient to account for it. The only thing he couldn’t describe in full mathematical detail was the human brain itself.
    Thirty years later, the physicist Eugene Wigner picked up on the idea and made a controversial but mathematically necessary step.  Since Von Neumann's calculations could show no possible way of triggering the collapse, Wigner concluded it had to be hiding in the one place he couldn’t describe.  The human mind was somehow the reason wavefunctions collapse.
    If you videod the experiment and then waited for a year, the particle wouln’t actually pick a state to be in until you watched the playback, at which point it would crystallise into existence.  In other words, a video camera watching the toys in Andy's room would see them dancing around, but it's only when a conscious human mind watches the playback that everything appears normal and they just see a lifeless toy.
    Wigner wasn’t necessarily happy about this.  He didn’t want to introduce non-testable terms into the theory, but he saw no alternative.  The maths said wavefunction collapse couldn’t be triggered by anything in the experiment, so it had to be the observer’s brain doing it. 
    This idea came to be known as the “Von-Neumann - Wigner Interpertation”.  Consciousness, according to this view, was a fundamental part of physics because there was no way of explaining how a particle “knew” to start existing in one certain state.  The idea is that reality is therefore anthropic.  Observing a particle causes it to change its nature.   And this is where spirituality gets included.
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I'm John Von Neumann...you got a friend in me.
Getting Spiritual
    All of these ideas about consciousness being a fundamental ingredient of the Universe sound very similar to certain religious teachings.  It’s completely understandable that many spiritualists would therefore endorese the VN-W interpretation.  It SEEMS like physics is confirming their spiritual preferences. 
    It's also where a lot of aspirational philosophy gets involved.  Many spiritual teachers suggest that you can achieve a certain state of being/consciousness which makes the world manifest itself a certain way.  Things like the “law of attraction” claim that if you think positive thoughts and focus on things you want, they will begin to happen.  I’m paraphrasing spiritualism obviously...but that’s what many spiritualists do with quantum mechanics, so paraphrasing is obviously something they're OK with. 
    Quantum mechanics comes along and it appears to be saying something very similar to a lot of these spiritual philosophies.  "You create your reality", "Reality manifests itself in tune with you observing it", "your consciousness is a fundamental part of the Universe", "Your mind influences reality".  These are all really exciting ideas, suggesting that humans have incredible power to change the world.
    I understand why so many people get enthralled by it.  I really do.  But, I’m afraid this simply isn’t the case.  I am sorry if you hold these beliefs, but whoever told you that quantum mechanics supports these ideas was either lying to you or didn’t understand it as well as they thought they did.  Your spiritual beliefs may be true but they have nothing to do with quantum mechanics.
    If you’d rather go on believing the cheap version of quantum mechanics then I understand, and I invite you to stop reading now.  Otherwise, let’s take a look at what we actually know about the Von-Neumann Wigner interpretation.

1) You can’t determine the eigenstate
    According to the Copenhagen Interpretation, before the particle is observed it is in a variety of states simultaneously, called the wavefunction.  Then, when the measurement is taken, the wavefunction collapses to just one state, called “the eigenstate”.  But there is something very important here: consciousness may trigger the wavefunction to collapse but there is no way of influencing which eigenstate it actually collapses into.
    In the analogy of the Toys, we found that watching them forced them to crystallise into one location, but we couldn't actually influence where it was.  We have no interaction with them during their living state so we can only give a probability of where they're likely to appear.  
    Likewise, observing a particle does tell it to pick a state but the state has nothing to do with us.  Each possible eigenstate has a “probability amplitude” associated with it and the final state it collapses into is determined by that, not you.
     So while it might be ok to say “consciously observing causes it to take form”, anything which says “you can influence” is immediately invalid.  So I’m afraid all those motivational spiritual ideas about how your mind can shape reality have completely missed one of the fundamental points of QM.  You're an observer, not an influencer.
    I’m afraid your consciousness can only, at best, trigger reality to form, it can’t (in any way) influence what form that reality takes.  The principle of "controlled manifestation" is not based on quantum mechanics at all.  You can't influence reality with your mind.
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With one exception
2) Quantum Mechanics doesn’t apply to Macrostates
    The world we see around us obeys classical laws, not quantum ones.  When you’re talking about a single electron or a single atomic nucleus or the interaction between two neutrons, then yes you need to speak quantum.  But when you’re talking about humans or plants or avocados, quantum rules aren’t directly relevant.  And this is sort of obvious. 
    One of the reasons quantum mechanics is so surprising is because it is very different to the world we experience.  The everyday world doesn’t feature wavefunction collapse.  Toys don't spontaneously teleport because they are classical objects.  The electrons they're made of will be quantum, yes, but not the toys themselves.  Any macrostate (an object big enough for us to observe directly) is already in a clearly defined eigenstate.  Its wavefunction has collapsed.
    This raises another fantastic question which is: where does the boundary between quantum and classical behaviour occur?  If a spiritual teaching claims that your consciousness can trigger a wavefunction collapse of a tiny number of particles, by all means listen up.  But the moment they start applying it to the everyday world, (anything bigger than a molecule really) they’re going beyond what we can honestly say.

3) Observation Doesn’t Mean “Using your Senses”
     The analogy of the toys is potentially misleading because it implies that me looking with my eyes is what causes the toys to pick a location, but this isn’t what really goes on.  And this is why I was reluctant to use an analogy (but it was just too good to ignore).  The anology helps us get the basic idea of measurement problems, but it isn't to be taken literally.
     There’s a very simple demonstration of quantum mechanics I’ve used in my physics class.  You set up a laser and point it at a plate with two slits.  You’re giving each light particle the choice of where to go, slit A or slit B.  when I do this demonstration I ask my students whether or not looking at the laser or the slits will trigger wavefunction collapse and guess what...it never does.  The light particles always end up in impossible places for particles, which means looking at them actually had no effect. 
    This is with a classroom of 20 students and myself staring at it from all angles.  We are clearly observing the particles but they aren’t collapsing.
     When we talk about “taking a measurement” we mean shrinking down to the quantum level and taking a measurement there.  Collapsing the wavefunction is actually very hard.  It’s not really “looking at the two slits” it’s a complicated series of prisms and mirrors which can detect which slit a particle went through. 
     Yes, this form of observation and measurement does collapse the wavefunction.  And yes it’s still extremely spooky, but the collapse doesn't occur through consciousness alone.  You'd need a carefully set up, simple, quantum mechanical experiment as well as your mind to trigger it. 
    So any spiritualist who talks about your consciousness collapsing wavefunctions needs to point out that this only counts if what your consciousness is doing is reading the results of a very complicated experiment, not looking around with the five senses.
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Consciousness MIGHT collapse one of these, NOT your love life
4) The Brain is Part of the System
     The reason von Neumann was forced to propose consciousness was because it was the only part of the system he couldn’t describe.  It was the black-box of mysteries.  To be clear, the human brain is still mysterious but mysterious doesn’t mean "outside of the normal laws of nature".  It just means we don’t know the details yet.  We know that the brain is composed of particles and those particles follow the same laws as particles in the experiment.
     Von Neumann showed that no part of the experiment was obviously the cause of wavefunction collapse, but many people pointed out that the brain couldn't be the cause either because wouldn't the brain have to observe itself in order to collapse its own wavefunction?  For the brain to obseve the paticle it must be in one particular state, meaning it too needs to be observed.  Wouldn't this require a consciousness within a consciousness, and so on to infinity.
    The brain differs only in completxity, not in character.  It’s still a particle detector, just a more elaborate one.  So I’m afraid invoking consciousness doesn’t help us explain wavefunction collapse.  Unless you want to take things to infinity.  
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Or further than that.
5) The Copenhagen Interpretation isn’t Necessary
     A lot of spiritualist teachers imply that ALL physicists agree with Wigner's idea, or that it is a widespread belief among quantum physicists.  It isn't. 
    John von Neumann's Idea is very interesting and certainly worth discussing, but there aren't labs full of quantum theorists talking about consciousness.  Consciosness is invoked in ONE version of the Copenhagen Interpretation but the Copenhagen Interpretation isn't the only game in town.  There are other explanations of the measurement problem which account for the data just as well.  The Copenhgen interpretation is a propsal but it's not a necessary one.  Quantum mechanics works without it.
    Erwin Schrodinger himself (the man who essentially gave us the first law of quantum mechanics) thought the Copenhagen interpretation made no sense.  And that’s saying something because Schrodinger was known for his spiritual beliefs and interest in Eastern religious philosophy. 
    His famous “cat” thought-experiment is actually a powerful disproof of the Copenhagen interpretation because the idea of a particle existing in many states and then suddenly not, is ludicrous.
    Einstein and deBroglie (who also won Nobel prizes for their work on quantum mechanics) favoured an interpretation which talked about hidden properties that couldn’t be detected.  They basically thought the Toy Story version was correct - particles end up in impossible places isn't because they're everywhere simultaneously, but because they had characteristics we didn't know about.  In other words, the very opposite of the Copenhagen interpretation – that human consciousness could never play a part in what the particle does because we can never observe the whole system. 
    Then there is the most famous alternative to Copenhagen; Hugh Everett’s Many Worlds interpretation.  In that, rather than having the wavefunction collapse into one specific eigenstate, eigenstates separate from each other and become associated with different versions of the same observer i.e. the wavefunction never collapses it just decoheres, describing different versions of the system.
     Nobody knows which of the many interpretations is correct.  Granted, many physicists adopt the Copenhagen, and a few consider von Neumann’s take to be relevant.  But when you have competing explanations you don’t just pick the one you like most, you reserve judgement.

Will we ever know?
    As with any claim in Science, the answer to the measurement problem will have to wait until there is evidence favouring one of the interpretations.  If we can devise an experiment that gives evidence for one interpretation over another then we might get somewhere.  At the moment there is no experiment anyone has devised which will conclusively resolve the problem.  Although there are whisperings.
    Work carried out by Dylan Mahler provides some hints that the idea of "hidden variables" may be the correct interpretation, as was favoured by Einstein.  David Deutsch has claimed that quantum computing may be pointing to the "many worlds" interpretation as being correct.  And Lucien Hardy has even proposed experiments which might rule out consciousness once and for all (although the design is far from perfect).  But until someone can come up with a testable idea to explain the measurement problem we're stuck with interpretations rather than theories.

And so...
    Quantum Mechanics may, possibly, need to talk about consciousness at some point in the future if the other interpretations get ruled out.  If that happens that would be amazing.  I'll be the first person to say "wow, guess consciousness does cause wavefunction collapse"!  But even if consciousness is part of the discussion, it applies under very specific conditions and you have no control over it. 
    I think spiritualists are often trying to do good things.  They want to improve the world, and improve people's self-image.  This is wonderful.  But please, please, please don't start talking about things which aren't relevant.  We don't understand why humans have eyebrows but you don't suddenly say that reality is determined by eyebrow evolution.  That's another part of Science which is just as poorly understood.  Don't put the word "quantum" in your belief because it sounds cool!
    Try and make yourself a better person yes, but that doesn’t mean “trying to force the Universe to behave the way your mind wants it to be” in fact it means the exact opposite.  If you really want to better yourself, or the world, then go out and buy a book on quantum mechanics written by a Scientist who has studied it and start there.  I guarantee it will blow your mind. 
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Image credits:

consciousness brain art: ytimg
White flag: beforethecross
The Beatles: blastro
Godzilla: manapop
Schordinger's Equation: viswakeerthy
Weeping Angel: vignette2
Wavefunction Collapse diagram: afriedman
John von Neumann: wikimedia
Yoda: dilcdn
Slit Detector: Scienceblogs
Buzz Lightyear: cloudpix
Charlton Heston as Moses: imgflip (Image originally owned by Paramout Pictures)
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