Sorry… missed #84. The link is still available at Universe Today.
Now for #85… www.cheapastro.com… Space Carnival
…with a discussion on my favourite moon (no, not ours)… Triton
Day: January 3, 2009
what’s wrong with Determinism?
Computationally even relatively simple biological molecules can’t be emulated exhaustively – they exceed the computational power of the entire Universe (if it were a computer that is), thus purely first principles descriptions of any complex system are a nonsense. “Determinism” assumes infinite computational ability – Laplace’s Demon – but such just doesn’t obtain in the physical Universe.
So where has free-will vanished to, when even simple biomolecules are beyond deterministic prediction? It’s not free-will that’s threatened, but simplistic Determinism. Everything derived from “no free-will” is just cant and tendentious posturing. Human behaviour can’t be predicted in an absolute deterministic sense, even if we were just classical computers in essence. So give up the whole line of “there’s no free-will” – it’s meaningless from a scientific and human-level point of view. Only a God’s eye-view can make an utterly deterministic computation… and guess what? He’s not sharing the results with us!
Here’s the thing. Turing’s Non-halting proof means there’s no way of knowing in advance what a bit of not very complex software is going to do – will it continue forever or will it stop? Why should humans be any less complex and any less beyond prediction?
You might think “Well that doesn’t mean that the program’s future behaviour is not determined by its previous states.”
But by what do you mean “determined”? And who can judge whether it is or isn’t 100% “determined” or partially stochastic or partially “random”? In principle you can’t! So “determined” is operationally meaningless. It serves no descriptive purpose for complex systems. Doesn’t mean that non-determined things can’t exhibit statistical regularities – radioactive decay is inherently unpredictable, but it’s still layfully obeying the Law of Large Numbers and so forth. But what it does mean is the ideas of “freedom” and “free will” aren’t meaningless because lower level laws are inherently deterministic either. The evolution of a system down a particular branch of probable outcomes (one of Everett’s Many Worlds) is no more predictable than its evolution down any other branch, yet the ensemble of Possible Worlds is governed by quantum mechanics, a deterministic theory.
Freedom, free-will and Determinism.
Meet the Cousins of Our Ancestors #1
No surviving species today is the same as a fossil or hypothetical form claimed to be an intermediate form, but living creatures preserve historical information that is otherwise lost to us in their unique adaptations and the adaptations they share with fossil/hypothetical forms. So whenever the press says a living creature is somehow “ancestral” or “primitive” it’s a furphy. A characteristic or two might retain features from long ago, but the lineages of all creatures alive today have been evolving for exactly the same length of time. Some lineages might evolve very quickly – if only to stay in the one place – but we’ve all had the same timespan to evolve in.
With that caveat consider the Ascidians or Tunicates, filter-feeders who, oddly, make a cellulose coat (‘tunic’) and, at some point in their lives, share certain features with our own Chordate/Vertebrate lineage. So who are the Tunicates? Sea-squirts are the ones we encounter most commonly, but there are a few other fascinating Tunicates who don’t just cling to rocks – Salps (Thaliacea), Doliolids, and Pyrosomes.
Salps can form incredibly large colonial masses and suffer massive die-offs when their population overloads – this happily sends carbon to the bottom of the sea to get buried, and thus form a major part of the carbon cycle.
Doliolids also form colonies, though quite differently to salps. They have a rather complicated alternating breeding system – propagating asexually part of the time, then sexually.
Pyrosomes really piqued my interest because they form huge tubular colonies – many metres long and sometimes wide enough for divers to swim into. They’re also bioluminescent.
Isn’t the natural world amazing?