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Posted by Prof_Sigmund 2 days ago

A True Life Hack: What Physical 'Life Force' Turns Biology's Wheels?(www.quantamagazine.org)
116 points | 22 comments
pawelduda 2 hours ago|
Truly mind blowing. A few days ago I found this animation [1] that shows it in motion

[1] https://www.reddit.com/r/educationalgifs/comments/17squg1/ho...

djokkataja 3 hours ago||
This reminds me of a gem of a comment from about a month back, about a dead simple Russian guidance system from a Cold War-era missile: https://news.ycombinator.com/item?id=47389285

Actually, someone even commented in that thread about how it was similar to biological mechanisms: https://news.ycombinator.com/item?id=47390619

kranner 1 hour ago||
For explorations of simple mechanisms like this leading to complex behaviour, Valentino Braitenberg’s book Vehicles is a classic.
bryancoxwell 50 minutes ago||
Would it do well on a Kindle or does it rely on illustrations?
kranner 38 minutes ago||
Definitely relies on illustrations.

The author passed away 15 years ago so I will mention the PDF of the book shows up in the first few search results on Google.

bryancoxwell 18 minutes ago||
Thanks!
sandworm101 28 minutes ago||
Simple spin-scan but with a rolling airframe. The technique is still used today. It is simple only if one looks at individual components. The total package is a different beast.

https://en.wikipedia.org/wiki/RIM-116_Rolling_Airframe_Missi...

Almured 7 hours ago||
What I find fascinating is the extreme efficiency of what is effectively an electric motor, reaching nearly 100% efficiency. At human scale we struggle with heat dissipation and friction
ssivark 5 hours ago|
But at the same time the motor is extremely finicky/fragile in the source of energy (negentropy) it will accept, while natural life is extremely hardy and adaptable.

I wonder how much of machine-like "efficiency" is actually "overfitting" at the cost of robustness.

anjel 4 hours ago|||
For more complicated organisms, robustness comes in the form of cellular turnover, and regenerative healing in response to injury, at least in youth. I wonder though if single celled organisms have or even need such a function.
brazzy 2 hours ago||
Individual cells absolutely do have mechanisms to repair damage: https://pmc.ncbi.nlm.nih.gov/articles/PMC5664224/

They can even repair their own DNA: https://en.wikipedia.org/wiki/DNA_repair

Almured 5 hours ago||||
That is a fair point to be honest! I guess when you a 20min lifetime you can probably compromise on reliability in favour of extra efficiency
01HNNWZ0MV43FF 4 hours ago||
Every race, the engine of a top-fuel dragster only completes about 900 revolutions and then has to be rebuilt! https://www.motortrend.com/features/top-fuel-dragsters
01HNNWZ0MV43FF 4 hours ago|||
The need to reproduce and repair our bodies is a big trade-off.

Electric motors are sort of like hermit crab shells - Hard and long-lasting, but they only exist because they piggyback off of a living species.

pazimzadeh 6 hours ago||
at the scale that it operates, the flagella is more a drill than a propeller

there's a good richard feynam video about how things feel when they're that small https://www.youtube.com/watch?v=4eRCygdW--c

abhikul0 6 hours ago||
Relevant Smarter Every Day video: https://www.youtube.com/watch?v=VPSm9gJkPxU
bacteriumiu 4 hours ago||
Article stopped exactly where stuff got interesting.

This whole "protons entering bacterium and being pumped out" is exactly the ancestor of the mitochondria, that's what it does, except now the "outside" is the inside of the parent cell.

cineticdaffodil 1 hour ago||
To not use the motor is to prolong its life? So do not heat your body with the motor?

Also can work as atp generator by applying rotation ?

zimpenfish 6 hours ago|
For some context, a billion years at a 20 minute breeding cycle is 26.3 trillion generations.
ur-whale 5 hours ago|
> For some context, a billion years at a 20 minute breeding cycle is 26.3 trillion generations.

Which if you want an actual feel for the true scale of things, must be multiplied by (order of magnitude) the number of bacteriums on the planet.

f6v 4 hours ago|||
> Which if you want an actual feel for the true scale of things

The caveat is that more zeros do nothing for our comprehension of the scale. That's the problem because most people can't comprehend how evolution is even possible. We just don't have a mental model for a trillion, it's all the same to us after a certain threshold.

zimpenfish 4 hours ago|||
Good point, forgot about that. Add another 10-20 zeros?