By Martin Zaltz Austwick
Companion episode: The World Outside My Window
I have a doctorate, a significant chunk of which involves Quantum Computing – I’m not showing off, it’s not a very impressive thesis, but it’s relevant – but there’s one thing (well, many things) I never understood. You may have heard how Quantum Computing requires a huge amount of parallelism – many calculations being done at once. So rather than figuring out 1 + 1 OR 1 + 2, it does both at the same time. Quantum Mechanics lets you do this because Quantum bits are spooky and can be both 1 and 2 at the same time. Well, obviously it’s a bit more complicated, but that’s the basic idea – do all the calculations at once, and then pick the right answer at the end.
This is the bit I got confused by. By the end, your computer has to evolved to a classical state – the answer has to be 2, or 3, or whatever. It can’t be 2 and 3 at the same time. Well, it can, in theory, but then when you read the output, you collapse the wavefunction and the computer randomly* says “2” or “3”. That’s not a very useful computer – one which gives a different answer depending on when you ask it, with no consistency. It needs to evolve to a specific number. Either 2 or 3.
And that’s the bit I didn’t understand. It’s not a deep conceptual question, it’s a question of algorithm design – how to create a series of operations that starts with a classical/definite state, evolves through a wonderful undetermined quantum state that employs this wibbly-wobbly parallelism, and then ends up with a sensible, definite answer at the end. Anyway, I don’t know the solution, but it is what informed this song – something with a definite starting point that splits into multiple possible paths but ends up somewhere common.
The Garden of Branching Lyrical Paths isn’t too hard to conceptualise. It’s how the first verse works. Every version of this song has the same first line. Then there are 2 choices for the second line. For each of those choices there are two choices for the third line, and for each of those lines, there are 2 choices for the fourth line. That leads to 8 possible versions of the first verse, starting with the same first line but getting increasingly dissimilar from each other.
The easy option conceptually would have been to keep branching – so for the second (and final) verse, there would 16 first lines, then 32 second lines, 64 third lines, and 128 final lines. Obviously that’s not the easy option in terms of the amount of lyrical material it would generate, so instead, I went down the quantum computing route – every version of the song, as well as having the same first line, has the same final line (the final line of the second verse). Working back, the second verse has four lines: the first has 8 choices, the second has 4 choices, the third has 2 choices, and then there’s one shared final line. Which of the 8 choices is used is determined by which of the 8 choices are used in the final line of the first verse. So, there are only 8 versions of these lyrics.
This is slightly complicated by the middle eight – here, there are 4 lines, each with 4 choices. These are written to work in any combination. There are 4x4x4x4 = 256 choices for the middle eight. Combined with the 8 verse options, this leads to 2,048 lyrical versions of this song, most of them only varying by one line.
But wait! Jeff pointed out to me that People Do Not Listen To Lyrics (I dispute that and maintain only that Most People Do Not Listen To Lyrics). So the arrangement of the song changes too. There’s an acoustic guitar which forms the base of this song, then there’s a harmony part, a choice of 5 keyboard or guitar parts; 4 drum parts; two bass parts; and seven instrumental solos, for 280 possible combinations. If you do listen to lyrics, that makes 573,440 versions of the song. The songs refreshes every day, so it would take around 1,571 years to generate every version, assuming it doesn’t repeat. Even I don’t want to hear it that many times.
If you’re a video games fan, you may notice that the main refrain – “I don’t feel alone in this world anymore” – carries a passing echo of “I don’t feel at home in this world anymore”, featured in Cardboard Computer’s Kentucky Route Zero, which I may have been playing a lot of while I stared out the window of a 4th floor living room in the middle of a pandemic lockdown. That’s a great song and a great game, if you’re looking for something to tide you over as you iterate between the 573,440 versions of this song in a 7 year long playlist. That’s making me feel slightly nauseous tbh.
*It seems random
Neutrinowatch 