Alien life may not be carbon-based, new study suggests...

[Jan Panteltje]

Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

 

[a a]

The idiot Jan Panteltje <alien@comet.invalid> persisting in being an Off-topic troll...

--
Jan Panteltje <alien@comet.invalid> wrote:

Path: not-for-mail
From: Jan Panteltje <alien@comet.invalid
Newsgroups: sci.electronics.design
Subject: Alien life may not be carbon-based, new study suggests
Date: Sun, 24 Sep 2023 04:12:28 GMT
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X-Received-Bytes: 1420

 

[Anthony William Sloman]

On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:

Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

--
Bill Sloman, Sydney

 

[Jeff Layman]

On 24/09/2023 10:38, Anthony William Sloman wrote:

On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

Well, to misquote a well-known series, \"It might be life, but not as we
know it\". If you believe that AI is going anywhere, then it might be
well to consider that the next from of life might not be
organically-based, but is fabricated from many component parts. In that
case, a creative, self-aware intelligent robot might well be
silicon-based (or based any other semiconductor material).

--

Jeff

 

[Anthony William Sloman]

On Sunday, September 24, 2023 at 9:55:44 PM UTC+10, Jeff Layman wrote:

On 24/09/2023 10:38, Anthony William Sloman wrote:
On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

Well, to misquote a well-known series, \"It might be life, but not as we know it\". If you believe that AI is going anywhere, then it might be well to consider that the next from of life might not be
organically-based, but is fabricated from many component parts. In that case, a creative, self-aware intelligent robot might well be silicon-based (or based any other semiconductor material).

But they\'d have to build a whole industrial base to replicated themselves. That\'s not going to arise spontaneously. which is no guarantee that the rest of the universe isn\'t full of it.

--
Bill Sloman, Sydney

 

[a a]

The idiot Jeff Layman <Jeff@invalid.invalid> persisting in being an Off-topic troll...

--
Jeff Layman <Jeff@invalid.invalid> wrote:

Path: not-for-mail
From: Jeff Layman <Jeff@invalid.invalid
Newsgroups: sci.electronics.design
Subject: Re: Alien life may not be carbon-based, new study suggests
Date: Sun, 24 Sep 2023 12:55:34 +0100
Organization: A noiseless patient Spider
Lines: 22
Message-ID: <uep83m$1b4i4$1@dont-email.me
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29eea2aa-2e84-4291-b1c1-635762e87b40n@googlegroups.com
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X-Received-Bytes: 2274

 

[Jasen Betts]

On 2023-09-24, Anthony William Sloman <bill.sloman@ieee.org> wrote:

On Sunday, September 24, 2023 at 9:55:44 PM UTC+10, Jeff Layman wrote:
On 24/09/2023 10:38, Anthony William Sloman wrote:
On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

Well, to misquote a well-known series, \"It might be life, but not as we know it\". If you believe that AI is going anywhere, then it might be well to consider that the next from of life might not be
organically-based, but is fabricated from many component parts. In that case, a creative, self-aware intelligent robot might well be silicon-based (or based any other semiconductor material).

But they\'d have to build a whole industrial base to replicated themselves. That\'s not going to arise spontaneously. which is no guarantee that the rest of the universe isn\'t full of it.

As I understand it viruses are currently considered to be alive.
This loweres the bar somewhat.

--
Jasen.
🇺🇦 Слава Україні

 

[Jeff Layman]

On 24/09/2023 14:18, Anthony William Sloman wrote:

On Sunday, September 24, 2023 at 9:55:44 PM UTC+10, Jeff Layman wrote:
On 24/09/2023 10:38, Anthony William Sloman wrote:
On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

Well, to misquote a well-known series, \"It might be life, but not as we know it\". If you believe that AI is going anywhere, then it might be well to consider that the next from of life might not be
organically-based, but is fabricated from many component parts. In that case, a creative, self-aware intelligent robot might well be silicon-based (or based any other semiconductor material).

But they\'d have to build a whole industrial base to replicated themselves. That\'s not going to arise spontaneously. which is no guarantee that the rest of the universe isn\'t full of it.

To invoke another fictional idea, I was thinking more of the
Cyberdyne/Skynet situation from the \"Terminator\" films. In those, it is
humans who create Skynet They then lose control of it, and the AI beings
become the dominant form of life. As those AI beings can create more and
more complex and terminators, I assume that meets the requirement of a
replicating - and adapting and advancing - form of life.

--

Jeff

 

[Öö Tiib]

On Monday, 25 September 2023 at 06:30:51 UTC+3, Jasen Betts wrote:

On 2023-09-24, Anthony William Sloman <bill....@ieee.org> wrote:
On Sunday, September 24, 2023 at 9:55:44 PM UTC+10, Jeff Layman wrote:
On 24/09/2023 10:38, Anthony William Sloman wrote:
On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

Well, to misquote a well-known series, \"It might be life, but not as we know it\". If you believe that AI is going anywhere, then it might be well to consider that the next from of life might not be
organically-based, but is fabricated from many component parts. In that case, a creative, self-aware intelligent robot might well be silicon-based (or based any other semiconductor material).

But they\'d have to build a whole industrial base to replicated themselves. That\'s not going to arise spontaneously. which is no guarantee that the rest of the universe isn\'t full of it.

As I understand it viruses are currently considered to be alive.
This loweres the bar somewhat.

There are over 100 definitions of life
<https://web.iitd.ac.in/~amittal/2011_2012_JBSD_Def_Life.pdf>
Since there is no consensus for a definition of life the question if viruses are alive or not is
meaningless for science.
So viruses are definitely alive in hand sanitiser ads (that claim to kill viruses). But
who believes ads?

 

[Anthony William Sloman]

On Monday, September 25, 2023 at 4:56:38 PM UTC+10, Jeff Layman wrote:

On 24/09/2023 14:18, Anthony William Sloman wrote:
On Sunday, September 24, 2023 at 9:55:44 PM UTC+10, Jeff Layman wrote:
On 24/09/2023 10:38, Anthony William Sloman wrote:
On Sunday, September 24, 2023 at 2:12:37 PM UTC+10, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Silicon isn\'t a likely starter. There\'s only 30% as much in the universe as there is carbon, and its complex compounds fall apart more easily. There are more d-orbitals than p-orbitals. which mean a wider range of potential fragments.

Well, to misquote a well-known series, \"It might be life, but not as we know it\". If you believe that AI is going anywhere, then it might be well to consider that the next from of life might not be
organically-based, but is fabricated from many component parts. In that case, a creative, self-aware intelligent robot might well be silicon-based (or based any other semiconductor material).

But they\'d have to build a whole industrial base to replicated themselves. That\'s not going to arise spontaneously. which is no guarantee that the rest of the universe isn\'t full of it.
To invoke another fictional idea, I was thinking more of the
Cyberdyne/Skynet situation from the \"Terminator\" films. In those, it is
humans who create Skynet They then lose control of it, and the AI beings
become the dominant form of life. As those AI beings can create more and
more complex and terminators, I assume that meets the requirement of a
replicating - and adapting and advancing - form of life.

Once a form of life can replicate itself - no matter how big, complicated and vulnerable the replicating mechanism can be - it has made it.

Discussions of how life can arise spontaneously from non-living materials are more constrained.

--
Bill Sloman, Sydney

 

[Martin Brown]

On 24/09/2023 05:12, Jan Panteltje wrote:

Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Autocatalytic reactions are very cute as are some of the diffusion
limited ones which can create patterns in sedimentary rocks that could
easily be mistaken for fossils. On balance I think it is far more likely
that life will evolve to use the most commonly available materials which
tend to be organic and carbon based since the elements CNO are available
in large amounts from supernova ejecta.

Heavier elements are all comparatively rare. One of the prettiest self
catalysing reactions is the cerium ion based chemical clock first
discovered by Belousov in the Soviet Union in the 1950\'s where he wasn\'t
believed and couldn\'t publish it because he couldn\'t fully explain it.

A decade later Zhabotinsky figured out the reactions and succeeded in
publishing it but it wasn\'t until an international conference in 1968
that western chemists became aware of it. It was a huge surprise since
it was a very simple recipe with incredibly complex behaviour.

It is possible to build reaction vessels to implement a nand gate in
this liquid chemistry environment so it is formally Turing complete!

https://en.wikipedia.org/wiki/Belousov–Zhabotinsky_reaction

I wouldn\'t rule out other life forms using chemical energy rather than
photosynthesis (like at black smokers on Earth) but I think it is a bit
far fetched for them to be other than carbon, sulphur or maybe silicon
based. No other elements can support a varied enough chemistry.

--
Martin Brown

 

[a a]

The idiot Martin Brown <\'\'\'newspam\'\'\'@nonad.co.uk> persisting in being an Off-topic troll...

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Martin Brown <\'\'\'newspam\'\'\'@nonad.co.uk> wrote:

Path: not-for-mail
From: Martin Brown <\'\'\'newspam\'\'\'@nonad.co.uk
Newsgroups: sci.electronics.design
Subject: Re: Alien life may not be carbon-based, new study suggests
Date: Mon, 25 Sep 2023 09:25:27 +0100
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[a a]

The idiot Jeff Layman <Jeff@invalid.invalid> persisting in being an Off-topic troll...

--
Jeff Layman <Jeff@invalid.invalid> wrote:

Path: not-for-mail
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Newsgroups: sci.electronics.design
Subject: Re: Alien life may not be carbon-based, new study suggests
Date: Mon, 25 Sep 2023 07:56:27 +0100
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[a a]

The idiot Jasen Betts <usenet@revmaps.no-ip.org> persisting in being an Off-topic troll...

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Jasen Betts <usenet@revmaps.no-ip.org> wrote:

Path: not-for-mail
From: Jasen Betts <usenet@revmaps.no-ip.org
Newsgroups: sci.electronics.design
Subject: Re: Alien life may not be carbon-based, new study suggests
Organization: JJ\'s own news server
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[a a]

The idiot =?UTF-8?B?w5bDtiBUaWli?= <ootiib@hot.ee> persisting in being an Off-topic troll...

--
=?UTF-8?B?w5bDtiBUaWli?= <ootiib@hot.ee> wrote:

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[Tabby]

On Monday, 25 September 2023 at 09:25:37 UTC+1, Martin Brown wrote:

On 24/09/2023 05:12, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.
Autocatalytic reactions are very cute as are some of the diffusion
limited ones which can create patterns in sedimentary rocks that could
easily be mistaken for fossils. On balance I think it is far more likely
that life will evolve to use the most commonly available materials which
tend to be organic and carbon based since the elements CNO are available
in large amounts from supernova ejecta.

Heavier elements are all comparatively rare. One of the prettiest self
catalysing reactions is the cerium ion based chemical clock first
discovered by Belousov in the Soviet Union in the 1950\'s where he wasn\'t
believed and couldn\'t publish it because he couldn\'t fully explain it.

A decade later Zhabotinsky figured out the reactions and succeeded in
publishing it but it wasn\'t until an international conference in 1968
that western chemists became aware of it. It was a huge surprise since
it was a very simple recipe with incredibly complex behaviour.

It is possible to build reaction vessels to implement a nand gate in
this liquid chemistry environment so it is formally Turing complete!

https://en.wikipedia.org/wiki/Belousov–Zhabotinsky_reaction

I wouldn\'t rule out other life forms using chemical energy rather than
photosynthesis (like at black smokers on Earth) but I think it is a bit
far fetched for them to be other than carbon, sulphur or maybe silicon
based. No other elements can support a varied enough chemistry.

Earth life is chemically complex, but minimised machines to o the essentials are less chemically complex. It seems Occam was ignored on Earth.

 

[Jan Panteltje]

On a sunny day (Mon, 25 Sep 2023 09:25:27 +0100) it happened Martin Brown
<\'\'\'newspam\'\'\'@nonad.co.uk> wrote in <uerg5p$1qoba$1@dont-email.me>:

On 24/09/2023 05:12, Jan Panteltje wrote:
Alien life may not be carbon-based, new study suggests
https://www.space.com/alien-life-not-carbon-based-autocatalysis-common
Intriguing \'autocatalytic\' reactions appear to be far more common than scientists had thought.

Actually a search of 2 centuries of digitized documents?
Not sure how / if such old experiments will be valid.

Autocatalytic reactions are very cute as are some of the diffusion
limited ones which can create patterns in sedimentary rocks that could
easily be mistaken for fossils. On balance I think it is far more likely
that life will evolve to use the most commonly available materials which
tend to be organic and carbon based since the elements CNO are available
in large amounts from supernova ejecta.

Heavier elements are all comparatively rare. One of the prettiest self
catalysing reactions is the cerium ion based chemical clock first
discovered by Belousov in the Soviet Union in the 1950\'s where he wasn\'t
believed and couldn\'t publish it because he couldn\'t fully explain it.

A decade later Zhabotinsky figured out the reactions and succeeded in
publishing it but it wasn\'t until an international conference in 1968
that western chemists became aware of it. It was a huge surprise since
it was a very simple recipe with incredibly complex behaviour.

It is possible to build reaction vessels to implement a nand gate in
this liquid chemistry environment so it is formally Turing complete!

https://en.wikipedia.org/wiki/Belousov–Zhabotinsky_reaction

I wouldn\'t rule out other life forms using chemical energy rather than
photosynthesis (like at black smokers on Earth) but I think it is a bit
far fetched for them to be other than carbon, sulphur or maybe silicon
based. No other elements can support a varied enough chemistry.

Thank you for the link, took a while to read it all.

 

[Anthony William Sloman]

On Tuesday, September 26, 2023 at 9:26:16 AM UTC+10, Tabby wrote:

On Monday, 25 September 2023 at 09:25:37 UTC+1, Martin Brown wrote:
On 24/09/2023 05:12, Jan Panteltje wrote:

<snip>

I wouldn\'t rule out other life forms using chemical energy rather than
photosynthesis (like at black smokers on Earth) but I think it is a bit
far fetched for them to be other than carbon, sulphur or maybe silicon
based. No other elements can support a varied enough chemistry.
Earth life is chemically complex, but minimised machines to o the essentials are less chemically complex. It seems Occam was ignored on Earth.

Occams\'s razor is a constraint on explanations, not mechanisms. Life can be be just as complex as it can replicate reliably - there\'s no other absolute constraint.
Of course if a competitor can evolve a simpler solution that work better, you are toast, but the rip-it-up-and start-over-option open to designers isn\'t available in evolutuion.

--
Bill Sloman, Sydney

 

[Martin Brown]

On 26/09/2023 05:27, Jan Panteltje wrote:

On a sunny day (Mon, 25 Sep 2023 09:25:27 +0100) it happened Martin Brown
\'\'\'newspam\'\'\'@nonad.co.uk> wrote in <uerg5p$1qoba$1@dont-email.me>:


A decade later Zhabotinsky figured out the reactions and succeeded in
publishing it but it wasn\'t until an international conference in 1968
that western chemists became aware of it. It was a huge surprise since
it was a very simple recipe with incredibly complex behaviour.

It is possible to build reaction vessels to implement a nand gate in
this liquid chemistry environment so it is formally Turing complete!

https://en.wikipedia.org/wiki/Belousov–Zhabotinsky_reaction

I wouldn\'t rule out other life forms using chemical energy rather than
photosynthesis (like at black smokers on Earth) but I think it is a bit
far fetched for them to be other than carbon, sulphur or maybe silicon
based. No other elements can support a varied enough chemistry.

Thank you for the link, took a while to read it all.

It is a really beautiful demo reaction for schools - especially in a
petri dish on an OHP (remember them?). I first saw it when George Porter
did it at the Royal Institution Xmas lectures in 1969 - unfortuately the
BBC tapes for that are missing He was *very* good. The B-Z reaction
was practically unknown in the West when he first showed it apart from
to a select few who had been at the conference the previous year.

https://www.rigb.org/christmas-lectures/watch-royal-institution-christmas-lectures-archive

Provided that you use distilled water (has to be chlorine/chloride free)
the recipe is very forgiving and works in almost all reasonable
proportions of bromate/perbromate and malonic acid. It is yellow to
clear with just cerium catalyst in and red to blue if you add Ferroin
indicator. It is by far the easiest chemical clock known.

The 1921 Brey/Leibhafsky iodide/iodate one with peroxide is by
comparison incredibly tetchy and only works if the wind is in the right
direction even for an experienced chemist (they too were not believed).
More on chemical clocks here:

https://en.wikipedia.org/wiki/Chemical_oscillator

There are many more single shot chemical clocks aka time fuses.

--
Martin Brown

 

[Martin Brown]

On 26/09/2023 00:26, Tabby wrote:

On Monday, 25 September 2023 at 09:25:37 UTC+1, Martin Brown wrote:

I wouldn\'t rule out other life forms using chemical energy rather than
photosynthesis (like at black smokers on Earth) but I think it is a bit
far fetched for them to be other than carbon, sulphur or maybe silicon
based. No other elements can support a varied enough chemistry.

Earth life is chemically complex, but minimised machines to o the essentials are less chemically complex. It seems Occam was ignored on Earth.

Not really true. Abiogenisis has to be sufficiently complex before it
can stand a chance of boot strapping up from mere chemical reactions.

Occam\'s razor says a theory should be as complex as is necessary to
explain the observations but no more than that.

It is quite possible that for life to advance beyond a coloured slime in
the sea and on the rocks surrounding it you actually need a sizeable
satellite in orbit like our moon to stabilise the planets spin and
create monthly variable tides. The latter is thought to have played a
very important role in allowing concentration of resources in rock pools
and then competition to stay alive there to increase complexity.

Life got started very quickly once the planet was cool enough to support
liquid water but it didn\'t advance much in the first billion years.

The big step forward was when Eukaryotes appeared 2.7bn years ago.

https://www.technologynetworks.com/cell-science/articles/prokaryotes-vs-eukaryotes-what-are-the-key-differences-336095

Then things really took off rapidly.

--
Martin Brown