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Would non-water based alien life have different life speed than us?

(I have studied some chemistry in CPGE in 1978-80, but I was very bad at it)

IIRC, chemical reactions are (exponentially) faster with temperature, i.e. because of Arrhenius equation.

So hypothetical life form in a lake of methane (e.g. bacteria on Titan) would, IIUC, be much slower than water-life on Earth. But I have no idea how much slower.

Let's suppose there would be bacterial life on Titan, and that we observe it in some optical microscope. Would the living cell appear moving very slowly, or not at all?

A more general form of my question would be related to alien intelligence? Is it conceivable that it would operate at speeds so widely different from ours (e.g. thinking or moving a billion times -or just a few hundred times- slower or faster than us) that we would not notice it?

Have life forms working a billion times faster -or slower- than us (or simply 100x times faster or slower than us) being scientifically imagined? By what plausible mechanism?

More or less "scientific" references and "explanations" (of the tutorial kind), or even science-fiction references (In the 1970s, as a teenager, I have read The Black Cloud) are welcome.

PS: notice that artificial intelligence software on current silicon computer is likely, if/when it would exist, to "think" and "live" 10x to 100x faster than us. In a few milliseconds an AI would make some cognitive steps that would take tenths of second to us humans

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    $\begingroup$ If I remember correctly, a rule of thumb is that 10 degrees Celsius give a factor 2 in the reaction speed. $\endgroup$ – celtschk Sep 25 '16 at 12:27
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SF References: The Waitabits by Eric Frank Russell has aliens that run a lot slower than us. Between the strokes of night by Charles sheffield has artificially slowed humans. Dragons Egg by Robert L Forward has life evolving on a neutron star that runs much (though not billions of times) faster than us.

As a general observation, running enormously slower than surrounding life is going to be a problem - you're likely to get eaten by something before you can react. At a billion times slower, Erosion is likely to be a problem...

And moving hugely faster is going to run into physical issues like air resistance - also moving things in a "reasonable" time from a hugely speeded up perception is likely to break them due to the forces needed to accelerate them fast enough. And that probably includes bits of the creature's body... move a stick (or a bone) with a 1g acceleration and you're fine. Try it with a billion g acceleration and it'll break.

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    $\begingroup$ Well, since all life on Titan would be at that low temperature and therefore slow speed, being slower than the surrounding life shouldn't be a problem here. $\endgroup$ – celtschk Sep 25 '16 at 12:58
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    $\begingroup$ True. For most things, it's only relative speed that matters; if everything is slower or faster then it doesn't matter - except where other physical issues come into it. Probably doesn't affect bacteria much, but if there's a current and your fish analogs want to avoid being swept away from their food source/ territory/ shelter then they need to be able to swim fast enough to cope with the currents. $\endgroup$ – JerryTheC Sep 25 '16 at 13:29
  • $\begingroup$ provably to slow or to fast life will newer get over bacteria stage $\endgroup$ – kifli Sep 28 '16 at 8:37
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Any single chemical reaction will run faster or slower depending on temperature, but you also have to account for the fact that biochemistries running in different solvent, adapted to different temperature ranges than ours, won't be using the same reactions. There are many spontaneous reactions that proceed quite vigorously at liquid methane temperatures (often involving substances that simply don't exist at all at our temperatures, because they are too unstable and decompose). Going in the other direction, there are reactions that would never be useful to life at our temperatures that proceed at quite a reasonable rate at, e.g., 300C in sulfuric acid solution, where most terrestrial biomolecules would be long gone.

That said, it does seem reasonable that, on average, the biological processes of an organisms based on liquid methane instead of water would run slower. But the rate at which chemical reactions run is not necessarily the most interesting quality to care about.

Other speeds that might be more consequential are things like

  1. How much power the organism can generate (energy production per unit time)
  2. How rapidly the cell cycle progresses / the lifespan or reproductive frequency of multicellular creatures.
  3. How fast the organism can move about in its environment.
  4. A sentient organism's subjective perception of time.

These are all related to each other, but they don't all change in lock-step. Even if metabolic reactions are individually slower, cold organisms could make up for it but having more metabolites / more mitochondria-equivalents in play at once. Additionally, while individual cells might not be able to move or morph very far very fast, large agglomerations of cells can multiply their mechanical effects, so that bulk muscle tissues in a multicellular creature could move "normally" from our perspective. Of course, how fast a multicellular creature could actually move will still be limited by how much power it can produce in its cells, and there will be a practical limit to how many metabolites and mitochondria you can pack into one cell, but you also have to consider that thermal efficiencies will be higher at lower temperatures.

So, would a Titan cell under a microscope appear to be moving very slowly, or not at all? Maybe, maybe not. It probably depends on the type of cell. There are, after all even terrestrial cells, living in extreme, energy-starved environments, that go years, decades, or centuries between divisions.

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    $\begingroup$ One thing to bear in mind. Evolution will select predators faster than their prey and prey faster than their predators. So complex life will in general run as fast as it's underlying chemistry can allow $\endgroup$ – nigel222 Sep 26 '16 at 19:42

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