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Steve Axford
05-09-2014, 6:17pm
Whilst doing a bit of re-reading about structural colours, I came across lots of references to photonic crystals. I had heard of these before, but previously took little notice. This time I looked deeper and soon realised why I took so little notice before. The maths is mind boggling. It is all about quantum things and lost me before they even started, but I persisted with the non-mathematical side of it, and I then came across molecular assemblers.
Just to go back a bit, photonic crystals are sometimes described as being the optical analogue of an electrical transister and are touted as being the potential basis for optical computers. Photonic crystals are assemblies of molecules with a very specific nanostructure. They can only be produced by molecular assemblers which are defined as a "proposed device able to guide chemical reactions by positioning reactive molecules with atomic precision". Well, it seems that these molecular assemblers have been present in nature for a very long time. One example is creating photonic crystals, another is DNA synthesis. We have yet to do this, but it can't be that far away.
I know this has nothing to do with photography (well, I don't think it has???), but it stuck me as quite fascinating. The possibilities are .... well, we just don't know what the possibilities are.

If you are interested in these things, do a search on Google, there is lots, some of it way to specialised, but some of it quite good.

jim
06-09-2014, 5:15pm
Quantum Theory Cannot Hurt You, or at least that is the title of a book I'm reading at the moment. The author is quite wrong about that as it hurts my poor little brain quite a lot, and he hasn't touched on anything as arcane as photonic crystals so far.

Steve Axford
06-09-2014, 5:27pm
Try molecular assemblers. I have no idea how the maths works, but then neither do many people, and nobody knows it well enough to make one. Evolution has made lots. Without them we don't exist.

I'll have to have a look at that book, though I doubt that I could ever understand the maths enough to understand how these things work. It will have to be enough for me to understand a little of what they do.

jim
06-09-2014, 6:16pm
The book is for a general audience, so nearly no maths. The stuff is still conceptually difficult, and without the maths I think you're getting little more than an impression of how it all works. I tried reading The Road to Reality by Roger Penrose, which is chock full of maths, but it defeated me.

Steve Axford
06-09-2014, 6:29pm
Yeah, but Roger Penrose is a mathematician and therefore a little weird (sorry to all mathematicians for that gross generalisation). If it contains little maths, I might give it a go. It is possible to understand this stuff, it's just hard to find anyone who can explain it in words. I recently managed to understand Einstein's General Relativity on gravitation, and that was written nearly 100 years ago. I'm slowly catching up :)

jim
06-09-2014, 6:54pm
Ok then, Quantum Theory Cannot Hurt You, a guide to the universe, by Marcus Chown. It's quite nicely written.

paulheath
06-09-2014, 7:48pm
i actually like AgBr + 2S2O3-- → Ag(S2O3)2--- + Br- followed by AgX(s) + 2 Na2S2O3(aq) → Na3[Ag(S2O3)2](aq) + NaX(aq), but hey that's just me:D

Steve Axford
06-09-2014, 8:07pm
Yeah, chemists are a bit weird too :). Paul, you may appreciate the marvel of molecular assembly where molecules can be made that cannot be made by nice chemical reactions, like the one you show above (what the hell is that anyway?). They could utilise enough energy to power the world - actually, they already do - it's called photosynthesis, and we and most other life lives on it.

Mark L
06-09-2014, 10:16pm
:eek::eek:
Got to finish some raised vegetable garden beds, then finish some wood skirting on a tank stand tomorrow. There's a Flame Robin been spotted down the the road that hopefully I'll have some time to try and find tomorrow arvo also (hope I can expose the reds well).
These are things I understand.;)

Steve Axford
06-09-2014, 11:36pm
I expect you to post some great images, Mark.