This is the WASTED BLOG. For my main author website, click this link.

Awards: WASTED won the Read it or Else category in the Coventry Award and was runner-up in the North East Book Award. It is longlisted for the Carnegie Medal and shortlisted for the Manchester, Grampian, Angus, and RED Awards.


Saturday, 1 May 2010

SCHRÖDINGER'S CAT - VERY WEIRD

Jack's band is called Schrödinger's Cats. I'd like to tell you why.

It relates, as many of you will realise, to a scientific conundrum commonly called Schrödinger's Cat or The Schrödinger's Cat paradox. It's one of the weirdest things to think about in the whole of physics and philosophy. Hardly anyone really understands it - I certainly don't! - and scientists argue about what it means.

It's called a "thought experiment" because it can't physically be proved. (Luckily for the cat.)

Here's the wikipedia entry.

And here is a nice clear video featuring a scientist with mad hair.

But I prefer this one, because you get to click a button and see whether the cat lives or dies - very like tossing a coin at the end of Wasted.


Confused? You're not alone! You are supposed to be confused. The scientist Niels Bohr said, "If anybody says he can think about quantum physics without getting giddy, that only shows he has not understood the first thing about them." And also, "If quantum mechanics hasn't profoundly shocked you, you haven't understood it yet."

(If you are stumbling on this for the first time, I blogged about quantum mechanics / physics here, and do read the comments, too, because they're very helpful.) 

Schrödinger wasn't saying that we have to believe that a cat can be dead and alive at the same time. He was saying that our current understanding of quantum physics suggests that the cat is dead and alive, which doesn't make sense, and either that therefore we haven't yet explained it properly, or that quantum science doesn't follow the rules of the rest of the universe. (Which we know is true - but we want to know what rules it follows.)

But the reason that Jack in Wasted is so interested in Schrödinger's Cat is that it's all about tiny (really tiny, invisible and impossible to observe even with a huge microscope) particles that change just by being observed**. And the idea that nothing is true until it's true. This is my explanation of Schrodinger's Cat - bearing in mind that I'm not a scientist but a philosopher by nature and training. "Everything is possible until it isn't." So, his idea is that if our lives seem ruled by chance (even though they're not - it just seems that way because we can't see or control the causes) then we can CHANGE what happens to us just by thinking about, or watching, or talking about what might happen.

For example, leaving the house five minutes earlier might make a big difference to your life - you might meet someone, or have an accident, or AVOID an accident. (I'm going to talk a lot more about that in later posts and ask you for your stories on May 4th.) Because we can't predict these things we don't bother to think about them - so, we don't think, "Hmmm, if I leave the house five minutes later, this will make a difference." We just leave the house without thinking. But Jack thinks that if we take control of small actions, we will affect our luck. We still won't control luck but we will affect it and feel in control.

**(Though, according to one of the helpful commenters on my recent blog post in the link above, the idea of observation here is not just the act of someone looking, but the measuring, which involves a physical act likely to change the particle. However, this is still why Jack is fascinated and why he calls his band Schrödinger's Cats.))
When I was at university, I studied philosophy, and specifically metaphysics, the discussion of how the world works beyond physics. We talked about truth, reality, knowledge, relativity, and a whole load more. Some of the things you have to puzzle over can drive you nuts! A philosopher can claim to prove that the table in front of you isn't real, which is very disconcerting if you want to put your mug of tea on it. So, you have to live your life as a normal person, and reserve the philosophy for fun. I think it's the same with quantum physics - we have to live our lives ignoring it, and just puzzle about it for fun.

Unless your job is to be a quantum physicist... In which case, I am happy for you to be dead and alive and work out for yourself just how that feels.

I'd love to know if any of you have any thoughts about Schrödinger's Cat, or if you can help me explain it better. But those of you who are serious scientists need to be careful - the rest of us are simple beings and are probably confused enough already...

THE WASTED BLOG TOUR - WHERE AM I TODAY? I am delighted to be over at Mary Hoffman's blog. Mary, aka the Book Maven, is a hugely successful and well-known author for young people and she's been kind enough to support me in lots of ways. Over there I'm talking about how writers prey on make use of the fact that readers can be made to suspend their disbelief; how even rational, sciencey people can, when engrossed in a story by a skilled story-teller, believe what we want them to believe. The reason I was thinking about that when I blogged for Mary is that last night, April 30th, was Walpurgis Night and I was doing an after-dinner speech at the Scottish Arts Club. Head over to Mary's to see what on earth that's got to do with anything!

PS - the speech went really well, though this was definitely the oldest audience I've ever spoken to and, although they were charming and laughed in all the right places, I don't think most of them had a clue what teenage fiction was about or why anyone would bother to write it! Maybe they should read this fabulous piece by one of my blog readers, womagwriter.

12 comments:

DJ Kirkby said...

I find this kind of 'stuff' very fascinating. Do you follow @marcuschown on twitter?

Lesley Cookman said...

Loved the post and the links. Haven't yet got my copy of Wasted, but feel it is a necessity now!

fairyhedgehog said...

In the book, I really don't think the technicality of what physicists mean by "observing" matters at all.

My brain is still reeling from reading Wasted. Wow! I must try and write a coherent review of it.

catdownunder said...

Of course I worry about the cat! I also do not understand the experiment. I think Stephen Hawking may understand it!

Old Kitty said...

I must admit I jumped to get a copy after reading the Chapter 39 extract of Spike the Cat.

:-)

Now my head just hurts and I'm having to read chapter 39 again!

Take care
x

womagwriter said...

Thanks for the link, Nicola!

Great post. I do love a bit of quantum physics with my morning cuppa.

Clare said...

Can I just add some words of re-assurance to science-phobics like myself who might be reading some of these posts with trepidation?

YOU DON'T NEED ANY BACKGROUND IN SCIENCE WHATSOEVER TO ENJOY "WASTED" - the book is thought-provoking and tackles some complicated concepts but in such a way that they are integral to the story so the reader is never overwhelmed. All you need is an open mind and a willingness to engage with the story.

I LOVED it - and I dropped science at 14 while my science teacher still had some hair left!

Nicola Morgan said...

DJ Kirkby - no, but how can I resist now?!

Lesley - hooray!

fairyhedghog - I agree, it doesn't. It's all about Jack's interpretation and relation to real life. And thank you for reeling after reading Wasted - I love that!

Cat - do not worry about the cat unless you believe you can kill it in a thought experiment.

Old Kitty - I'm glad you liked Spike's chapter. Someone commented in a review that it's very hard to bring animals into books without undermining their own-worldness and that i'd achieved it. I do rather love Spike and his independence!

Thanks, Womagwriter, and for your fab review on your blog!

Clare - thank you for pointing that out. You are absolutely right. (Otherwise, I couldn't have written it!)

fairyhedgehog said...

I was interested to Stumble across this piece which suggests that it isn't the physical contact with a particle that affects it when it's observed.

Someone is going to point out that when we "observe" one slit or the other, it really means that we're firing little energetic photons at it. It's not surprising that that will affect the system. Well have I got news for you! In 1978, John Wheeler proposed his "delayed choice" experiment in which a detector was set up to observe the slits after a particle had already passed through it, and this experiment was actually performed a few years ago. It turns out that you can retroactively force the wave function to collapse. That is messed up.

Now I really don't understand!

(Did I say that I really love the book?)

catdownunder said...

What? I do not have to worry about the cat? :-)

Anonymous said...

Actually Schrodinger's equation, the very heart of quantum mechanics, does not merely suggest the cat is both alive and dead, it unambiguously states it. Since we cannot see such superposed states it was thought for a long while that the equation does not tell the whole story: the superposition must "collapse" into a single classical state when it is observed. Alas we now know that this is not the case, an interaction with a single particle is sufficient to create the appearence of collapse and thus suffices as an observation, but, and this is crucial, with single particles the observation can be reversed, undone, erased and we once again have both possibilities in a superposition. It therefore follows that after an observation "the other cat" is still around somewhere. This was actually rather well explained by Hugh Everett in his Relative State formulation. Instead of assuming that the observer can see all the cats , whcih he clearly can't, what happens if the observer is includes in the quantum system: | radioactive atom + killing machine + cat + scientist> ? Put simply when the atom enters a superposition, so does the machine and the cat, and so does the observer. All the mystery of wavefunction collapse disappears as does the special role of the observer. There is no collapse, no random jumping and the observer is just part of the system. The superposition persists indefinitely with that part of the wavefunction that represents the
| no-decay, no activation, live cat, observer sees cat as alive >
state coexisting with the dead-cat counterpart. Put this way, the observer cannot see both cats because there are now two observers. The one who sees a live cat cannot see the dead one and vice versa. It all works apart from one niggling aspect - which is the vast number of "parallel universes" that are spawned with every microscopic interaction in the universe! Our metaphysical preferences will probably drive us to assume that somehow they all fade out of existence but as quantum erasure experiments prove, they certainly persist after an observation should have got rid of them.
Cheers, Derek

Anonymous said...

Actually Schrodinger's equation, the very heart of quantum mechanics, does not merely suggest the cat is both alive and dead, it unambiguously states it. Since we cannot see such superposed states it was thought for a long while that the equation does not tell the whole story: the superposition must "collapse" into a single classical state when it is observed. Alas we now know that this is not the case, an interaction with a single particle is sufficient to create the appearence of collapse and thus suffices as an observation, but, and this is crucial, with single particles the observation can be reversed, undone, erased and we once again have both possibilities in a superposition. It therefore follows that after an observation "the other cat" is still around somewhere. This was actually rather well explained by Hugh Everett in his Relative State formulation. Instead of assuming that the observer can see all the cats , whcih he clearly can't, what happens if the observer is includes in the quantum system: | radioactive atom + killing machine + cat + scientist> ? Put simply when the atom enters a superposition, so does the machine and the cat, and so does the observer. All the mystery of wavefunction collapse disappears as does the special role of the observer. There is no collapse, no random jumping and the observer is just part of the system. The superposition persists indefinitely with that part of the wavefunction that represents the
| no-decay, no activation, live cat, observer sees cat as alive >
state coexisting with the dead-cat counterpart. Put this way, the observer cannot see both cats because there are now two observers. The one who sees a live cat cannot see the dead one and vice versa. It all works apart from one niggling aspect - which is the vast number of "parallel universes" that are spawned with every microscopic interaction in the universe! Our metaphysical preferences will probably drive us to assume that somehow they all fade out of existence but as quantum erasure experiments prove, they certainly persist after an observation should have got rid of them.
Cheers, Derek