A Tale of Two Kitties, or How I Learned to Stop Worrying and Love a Cat

“And when Hell is full, the dead shall walk the earth.” So said George A Romero’s Dawn of the Dead. However that’s as close as this blog will get an undead moggy, despite my misleading talk of zombie cats at the end of the last entry. No, today I’d like to go on with an example of superposition in real life as proposed by Austrian physicist, Erwin Shrödinger.

We’ll get to his cat in a bit, but I think I’d best mention the preparations for our little play that have been made so far.  I say Our play as the production team for the Guild’s Copenhagen is slowly growing. Some names are still under wraps, as nothing is concrete yet, but negotiations to nab some top people are happening. I can announce that my Production Assistant/ Dramaturge/ Person-who-has-random-ideas-bound-off-them-at-ridiculous-times is Lindsey Welch. Bless her, as if she isn’t doing enough; what with performing in Guys and Dolls (tickets still available, folks), helping Stacey with the Youth Theatre, and being a teacher (and all the evening planning that involves), she agreed to help me get my ideas into a coherent whole to present to the cast.

Very ably assisting Linz is my Production Manager, the very wonderful Angela Atfield. Despite – or maybe because of – Angela’s relative innocence in the role, her enthusiasm and precise planning is a wonder to itself. At our first meeting, amongst a stack of papers, scripts and set designs, she took minutes, worked her way though a tightly ordered agenda and still managed to get the creative juices flowing (by the way, if you see a magnificent black mountain bike flying past you in the Gravesham area, it may very well be called Vala. Do say hello).

But we are still in need of people. Aside from as many of you as we can get to be at  the Guild on 30^th January from 10am for the first workshop, we may be in need of some technical bods. For those that love a challenge, the show requires a couple of Audio/ Video Operators. The main pairing will need to be available for rehearsals towards the end of the production schedule, and the show nights themselves. The roles are a fundamental part of the show, helping to illustrate the theme of perception and perspective. And, if everything goes to plan, they would be instrumental in giving this show its ‘that’s a bit different’ edge I’m looking for. So, if you are interested in the show, but don’t think you fit the character roles, then this could be a way to get involved – either way, faithful reader, you would be very welcome.

As to the characters, I’ve had a couple of comments about the ages as described elsewhere on the Guild website. Let me start by saying that regardless of your age, if you can convince the panel (Angela, Linz, Me and fellow Exec Member, Jane Fenlon) that you can embody the ideas and experiences of Margrethe, Niels and Werner, then so be it. As long the whole works from an audience point of view (e.g. the ages of the trio are in keeping with each other and the content) then we will obviously go with the best for the part. So again, if you have even a small urge to be with us, please come down and show us why you are the best for the show, and what you can pull out of your box of tricks.

And speaking of boxes of tricks…

Concerned that the newly proposed superposition of particles, the overlapping of potential placement, was a phenomenon exclusive to atomic structure, Schrödinger and Einstein – yes, the great man of reason and question – set out in letters a discourse regarding its application to larger, living entities. Schrödinger’s thought experiment went thus:

“A cat is penned up in a steel chamber, along with the following device (which must be secured against direct interference by the cat): in a Geiger counter, there is a tiny bit of radioactive substance, so small that perhaps in the course of the hour, one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges, and through a relay releases a hammer that shatters a small flask of hydrocyanic acid. If one has left this entire system to itself for an hour, one would say that the cat still lives if meanwhile no atom has decayed.”[1]

By this mechanism, Schrödinger was able to scale up the probability of the radioactive particle decaying (letting go of an electron from its atomic structure) – and its inherent probability that it will not decay – to a matter of life and death for a cat in a box.

Now the Copenhagen Interpretation of Quantum Physics, when applied to Schrödinger’s Cat states that until the box is opened and we have observed the result, we cannot with 100% certainty predict the outcome of the cat’s fate. As the particle may decay at any time over the hour of unobserved activity, the probability of it doing so can be translated as the cat being alive or dead (the particle being no-decayed/ decayed accordingly). Until we look, the outcome is undetermined, uncertain and incomplete. Hence the cat, unobserved, remains in two states. It is, according to the Copenhagen Interpretation, only at the moment of observation that the wave function of the particle (it being in two places at once, as suggested by the two slit experiment) collapses and one or the other becomes a true reality.

Of course, there are other interpretations of Quantum Physics to help make this more confusing. If you are interested – and if you’re a science fiction fan, this may be of particular interest – look up Many Worlds Theory, or the Relational Interpretation.

But that’s enough physics for today. I imagine that the next blog entry will have me and my team in the grip of workshop frenzy where I hope to be joined by as many of you as possible. Until then, be nice to cats.

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[1] Schrödinger, Erwin (November 1935). "Die gegenwärtige Situation in der Quantenmechanik (The present situation in quantum mechanics)". Naturwissenschaften. Via en.wikipedia.org/wiki/Schrödinger's_cat

"I used to be in two minds about Quantum Uncertainty, but now I'm not so sure..."

Happy New Year, fellow explorers! I trust you all had a good Christmas, no doubt full of festive foods, frothy beverages and jumpers in all shades of reindeer! Apologies must be given for the tardiness of this blog. Not a scrap of physical theatre (or theatrical physics) to quench your Christmas thirst had been produced. Too many responsibilities, too many commitments, too many mince pies. Oh to be in two places at once…

Much like the particle.

But how can our friendly particle be in two places at the same time, I hear you cry? (He’s at it again with the talking to himself, I also hear you whisper amongst yourselves.) Well, that is precisely what I’m going to discuss here. Things may get a little heavy as we go on, but stay with me (please, I get ever so lonely). This is all just information that feeds into the play, not the actual play itself. Yes, Heisenberg and the Bohrs talk of interpretations and nuclear orbits and radioactive bombardment, but they are just the items of discussion; the real meat of the play is how the three players interact, the truths they reveal, the secrets they harbour, and moments of doubt and pain and hurt and anger and isolation and joy and laughter – and dealing with them all at the same time. I will discuss more of this myriad of emotions that the characters experience as we get into the rehearsals.

So, if this all seems a bit complicated, which it can be (it is physics after all), don’t let it put you off the show. I love Castle and Drop Dead Diva[1] but know next to nothing about writing a novel[2], criminal law, being a lawyer or matching heels with a power suit[3]; it really doesn’t impact on my enjoyment of the narrative. It’s like watching the documentary about Blade Runner before you see the film: when certain bits turn up and scenes play out, you can see all the subtext and subtle links shine through, only adding to a brilliant movie.

I repeat in big important letters: THIS ISN’T THE SHOW – JUST SUPPORTING INFORMATION THAT WILL ONLY ADD TO YOUR ENJOYMENT. Honest.

So, let’s start with a tank of water.

The water is still, nothing is moving. We are at one end and a large blank screen is submerged at the other. A light shines across the surface of the water. Just for fun, we drop a pebble into our tank to watch the ripples spread across the surface towards the other side. Assuming the tank is wide enough the undulating wave with its peaks and troughs strikes the far screen without any side ‘echoes’. As the wave hits the wall we take a snapshot of the screen. With the light across the surface being disturbed by the waves, we can see a pattern form on the screen: at the centre of the screen, the light is completely blocked by the wave. As you look away from this central point, towards the sides of the screen, more light is visible. Let’s invert this image and imagine the water wave is light hitting a wall. Due to it’s curved nature spreading out from the dropped pebble, the amount of energy, demonstrated by the height of the wave, as it hits the flat, incurving wall decreases the further you get from the middle of the screen, directly opposite the dropped pebble/ imagined light source.

Let’s do it again. The water is calm; the light is shining across the screen. Now, we have two pebbles. We drop them at t he same time, at the same end of the tank, about a third of the way in from the sides. Now we have two sets of expanding ripples. Two ripples that begin to interact with each other[4]. One wave built of peaks and troughs begins to multiply the other. If two peaks meet, then the resulting wave is twice its starting height. If a trough meets another trough, it becomes a trough of twice its starting depth. If a peak meets a trough, then they cancel each other out. As this merging of energies surges across the surface, we again pause, take a snapshot and observe the screen. As before we have a gradient of light (we’ll cut to the chase here with the inversion of the image) peaking in the middle ands disappearing at the ends, but due to the crossing ripples, the smooth pattern is broken into stripes.

Shadow

Light.

Shadow.

Brighter light.

Shadow.

Very bright light.

Shadow.

Brilliant bright light.

Shadow.

Very bright light.

Shadow.

Brighter Light.

Shadow.

Light.

Shadow.

The two waves have produced an Interference Pattern.

Right hold that thought. Waves coming from two close sources will produce an interference pattern.

At the other end of the garage we have another screen, a vertical plank of wood with a slit in it, and a small automatic tennis ball server. Now the slit is just wide enough for a tennis ball through. And we have already marinated our tennis balls in paint (for that extra special flavour). Let’s fire it up!

For an hour or so we fire tennis balls at the plank. Those that get through splat against the screen, creating a lovely stripe of paint. Great. Pretty. Would take forever to paint the room.

So let’s double our chances of finishing the room: two slits in the plank.

As expected, we now get two parallel stripes.

Hold that thought, too. Tennis balls, our physical particles, make two lines when passed through two slits.

Okay, still with me – groovy. Let’s go small. Let’s change the tennis ball for an electron, a tiny particle of matter. If we scale down the plank of wood to electron size, we can fire the electrons through. And yes, we get a single line pattern from the single slit plank.

So far, so straight forward. Let’s try it with two slits. Twang, twang, Dakka-dakka-dakka. Feel free to add your own machine gun noises. And voila, the perfect example of two parallel – wait! What’s this? An Interference Pattern? Like the wave from the tank! Freaky.

But could it be the stream of electrons are colliding with each other, deflecting their path, and producing this weirdness? Let’s make it simple. Let’s fire one electron at the plank at a time. But no! Even with an isolated projectile, the Interference Pattern is still emerging after several shots at the wall. From this, and some highfalutin mathematics, it seems that the particle was passing through the slits as waves of potential and interfering with itself[5]. But the maths at this point makes this even stranger: As the electron leaves the launcher and before it hits the screen, the particle has:

            Gone through one slit

            Gone through the other slit

            Gone through both slits

            Gone through neither

                        …all at the same time!

This overlapping of potential positions is called Superposition, and it is the first part of Heisenberg’s Uncertainty Principle.

So far we’ve looked at the particle launcher and the screen – let’s study the slit to see what is happening down there. But oh the calamity! As we watch the particle leave the launcher, the electron will only do one of the four events listed above. This, over time, will only produce the two stripe pattern associated with matter going through the slits. If we shut the camera down, removing the observation, and run the experiment again, the Interference Pattern returns. It seems that by observing the experiment we are changing what the electron does and which pattern is produced.

Heisenberg theorised that we can’t know exactly how the particle will behave without destroying the wave nature of its movement and eradicating the Interference Pattern. By extrapolating this, he proposed that the more accurately we know the position of a particle, the less accurately we know its velocity, and vice versa[6]. All we can discover is the probability of where a particle may be, or at what velocity is travelling, not both.

So, particles in two places at once: Making Christmas easier a quantum at a time[7]. Now I’m off to scrape tennis ball paint of my garage walls, but next time we’ll have a look at Schrödinger and his zombie cat.

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[1] Oh the shame. Manliness out of the window. My name is Kevin, and I’m a Drop Dead Diva fan. And Castle has Nathan Fillion and Stana Katic in it, which is enough for anyone.

[2] As anyone who is reading this blog will tell you.

[3] Stop that sniggering.

[4] Ooh. And most definitely, Er.

[5] Nope. Not doing that joke, it’s juvenile.

[6] Copenhagen by Michael Frayn, page 150, Methuen Drama Edition, 2003.

[7] For more on light through slits, have a look at Young’s double slit experiment http://physics.about.com/od/lightoptics/a/doubleslit.htm