Friday, July 24, 2009

Origin of life: Current efforts to create life, or else find alternative life

In "Second Genesis: Life, but not as we know it," Bob Holmes (New Scientist, March 11, 2009) provides a summary of attempts to create artificial life (paywall).
We're still stuck with Life 1.0, the stuff that first quickened at least 3.5 billion years ago. There's been nothing new under the sun since then, as far as we know.

That looks likely to change. Around the world, several labs are drawing close to the threshold of a second genesis, an achievement that some would call one of the most profound scientific breakthroughs of all time.
However,
Venter's team at the J. Craig Venter Institute in Rockville, Maryland, plans to remove the genome from an existing bacterial cell and replace it with one of their own design. If successful, this will indeed result in a novel life form, but it is a far cry from the ultimate goal of a second genesis, as Venter would be the first to admit.

Other teams, however, are striving directly for that ultimate goal. The most ambitious of them do not even rely on the standard set of molecular parts, but seek to redesign a living system from first principles. If successful, they would provide an entirely new form ...
Meanwhile, others look for a shadow biosphere, an independent type of life sharing the planet with us.

My sense is that the people who use existing manufactured parts will have the best luck with their work.

Here's University of Colorado (Boulder) philosophy prof Carol Cleland'sargument in Astrobiology Magazine (12/01/06) for looking for a shadow biosphere:
The discovery of a shadow microbial biosphere would be philosophically and scientifically important. It is clear that familiar Earth life has a common origin, and hence represents a single example of life. Logically speaking, one cannot generalize on the basis of a single example. If we are to achieve a satisfactory understanding of the general nature of life, we need examples of unfamiliar forms of life.
Also, Holly Hight asks ("Does Earth harbour a shadow biosphere of alien life," Cosmos: The Science of Everything, 16 February, 2009 ):
Finding life that doesn't fit with the types we already know would be a strong indication that life developed more than one time here on Earth, increasing the chances of finding it elsewhere, said Paul Davies, an astrophysicist at Arizona State University in Tempe.

But nobody has ever seriously searched for microorganisms - or any form of life - different from the carbon-based, DNA-centred type of life about which we have long known.

If we do look, Davies said, "It's entirely feasible that we'll find a shadow biosphere," he told reporters at the annual meeting of the American Association for the Advancement of Science (AAAS) in Chicago.

"Our search for life [has been] based on our assumptions of life as we know it. Weird life and normal life could be intermingled, and filtering out the things we understand about life as we know it from the things we don't understand is tricky."
It must be hard to write science fiction these days.

Thursday, July 23, 2009

Guillermo Gonzalez on mutual eclipse seasons in three planets during the International Year of Astronomy

Gonzalez, author of Privileged Planet, has a new academic publication here.

Here's the abstract:
Mutual eclipses in the solar system

Guillermo Gonzalez 1

Copyright © 2009 Royal Astronomical Society

ABSTRACT
Guillermo Gonzalez notes another astronomical reason why IYA2009 is special: mutual eclipse seasons at Jupiter, Saturn and Uranus.

Abstract

Eclipses between the major moons of Jupiter and Saturn are occurring this year. The circumstances of these eclipses are compared to terrestrial solar eclipses. Suggestions for observing these events are presented.

Wednesday, July 22, 2009

Best-observed solar eclipse in human history?

NASA Science News for July 20, 2009 advises that
The longest solar eclipse of the 21st century takes place this Wednesday, July 22nd. The path of totality crosses many major cities, setting the stage for possibly the best-observed eclipse in human history.
FULL STORY here.

Sunday, July 19, 2009

Origin of life: Quantum mechanics provided the ... ooomph!! ?

In "The Quantum Life" (Physcisworld.com, July 1, 2009), Paul Davies, astrobiologist and director of BEYOND: Center for Fundamental Concepts in Science at Arizona State University, examines the case for quantum mechanics kickstarting the origin of life (Q-life):
But why should quantum mechanics be relevant to life, beyond explaining the basic structure and interaction of molecules? One general argument is that quantum effects can serve to facilitate processes that are either slow or impossible according to classical physics. Physicists are familiar with the fact that discreteness, quantum tunnelling, superposition and entanglement produce novel and unexpected phenomena. Life has had three and a half billion years to solve problems and optimize efficiency. If quantum mechanics can enhance its performance, or open up new possibilities, it is likely that life will have discovered the fact and exploited the opportunities. Given that the basic processes of biology take place at a molecular level, harnessing quantum effects does not seem a priori implausible.
It's intriguing, the way he attributes to "life" and, elsewhere, "evolution" the attributes of a planning and thinking intelligent agent.

He almost persuades himself but
Although at least some of these examples add up to a prima facie case for quantum mechanics playing a role in biology, they all confront a serious and fundamental problem. Effects like coherence, entanglement and superposition can be maintained only if the quantum system avoids decoherence caused by interactions with its environment. In the presence of environmental noise, the delicate phase relationships that characterize quantum effects get scrambled, turning pure quantum states into mixtures and in effect marking a transition from quantum to classical behaviour. Only so long as decoherence can be kept at bay will explicitly quantum effects persist. The claims of quantum biology therefore stand or fall on the precise decoherence timescale. If a system decoheres too fast, then it will classicalize before anything of biochemical or biological interest happens.
.So we are now into the business of persuading ourselves that, based on a few studies, that would not be the normal fate of Q-life. And in the end,
How would Q-life evolve into familiar chemical life? A possible scenario is that organic molecules were commandeered by Q-life as more robust back-up information storage. A good analogy is a computer. The processor is incredibly small and fast, but delicate: switch off the computer and the data are lost. Hence computers use hard disks to back up and store the digital information. Hard disks are relatively enormous and extremely slow, but they are robust and reliable, and they retain their information under a wide range of environmental insults. Organic life could have started as the slow-but-reliable “hard-disk” of Q-life. Because of its greater versatility and toughness, it was eventually able to literally “take on a life of its own”, disconnect from its Q-life progenitor and spread to less-specialized and restrictive environments — such as Earth. Our planet accretes a continual rain of interstellar grains and cometary dust, so delivery is no problem. As to the fate of Q-life, it would unfortunately be completely destroyed by entry into the Earth’s atmosphere.
All this reminds me of a beautiful Edith Wharton short story, "Fern Seed", which I can't find on line, or worse, it might be wrecked by some clueless "ethnicity/class/gender" analysis.

The point of "Fern Seed" is that it looks as though a ghost drove a story character to suicide - but there is no actual evidence. (If you ever think of writing a ghost story, take Wharton as your guide. What make her stories work is: No one can prove anything happened, apart from catastrophic emotional impacts, and yet everyone is sure that something happened.)

Saturday, July 18, 2009

Gravity doesn't make sense? ... hold that thought!

At New Scientist, Michael Brooks tells us "Seven Things That Don't Make Sense About Gravity," including

- If gravity were a tiny bit stronger, the universe as we know it would not exist

- From plants to quail, life of all stripes seems to need gravity to work properly

Uh ... so then gravity doesn't make sense because ... why, exactly? Because there wasn't supposed to be a solution to those problems? Why not?

It reminds me a bit of this earlier kvetching about gravity.

Fine tuning is a big problem for these people.

Tuesday, July 14, 2009

Cosmology: Crisis of the month - Gravitation

Cleaning out the In box, I noticed "Study Plunges Standard Theory of Cosmology Into Crisis" (ScienceDaily (May 5, 2009), in which we learn:
“The only solution would be to reject Newtońs classical theory of gravitation,” says Pavel Kroupa. “We probably live in a non-Newton universe. If this is true, then our observations could be explained without dark matter.” Such approaches are finding support amongst other research teams in Europe, too.

It would not be the first time that Newton’s theory of gravitation had to be modified over the past hundred years. This became necessary in three special cases: when high velocities are involved (through the Special Theory of Relativity), in the proximity of large masses (through the theory of General Relativity), and on sub-atomic scales (through quantum mechanics). The deviations detected in the satellite galaxy data support the hypothesis that in space where extremely weak accelerations predominate, a “modified Newton dynamic” must be adopted. This conclusion has far-reaching consequences for fundamental physics in general, and also for cosmological theories.

Astrophysicist Bob Sanders from the University of Groningen declares: "The authors of this paper make a strong argument. Their result is entirely consistent with the expectations of modified Newtonian dynamics (MOND), but completely opposite to the predictions of the dark matter hypothesis. Rarely is an observational test so definite."
Well, this is a nice change from speculation.

See also: "Time for a New Theory of Gravitation? Satellite Galaxies Challenge Newtonian Model" (ScienceDaily, Apr. 23, 2009) where some of the same cast of characters note the this problem:
The team of scientists looked at the distribution of these satellite dwarf galaxies and discovered they were not where they should be. “There is something odd about their distribution”, explains Professor Kroupa. “They should be uniformly arranged around the Milky Way, but this is not what we found.” The astronomers discovered that the eleven brightest of the dwarf galaxies lie more or less in the same plane - in a kind of disk shape - and that they revolve in the same direction around the Milky Way (in the same way as planets in the Solar System revolve around the Sun).

Professor Kroupa and the other physicists believe that this can only be explained if today’s satellite galaxies were created by ancient collisions between young galaxies. Team member and former colleague Dr Manuel Metz, now at the Deutsches Zentrum fuer Luft- and Raumfahrt, also worked on the study. “Fragments from early collisions can form the revolving dwarf galaxies we see today” comments Dr Metz. But he adds that this introduces a paradox. “Calculations suggest that the dwarf satellites cannot contain any dark matter if they were created in this way. But this directly contradicts other evidence. Unless the dark matter is present, the stars in the galaxies are moving around much faster than predicted by Newton’s standard theory of gravitation.”
Most interesting, but I'm not clear on what the "crisis" is.

Oh never mind. By fall, a different crisis.

Monday, July 13, 2009

You never know what'll turn up useful ...

In "Science, Spirituality, and Some Mismatched Socks" (Wall Street Journal, May 5, 2009)", Gautam Naik explains how "researchers turn up evidence of 'spooky' quantum behavior and put it to work in encryption and philosophy.":
Last year, Dr. Gisin and colleagues at Geneva University described how they had entangled a pair of photons in their lab. They then fired them, along fiber-optic cables of exactly equal length, to two Swiss villages some 11 miles apart. During the journey, when one photon switched to a slightly higher energy level, its twin instantly switched to a slightly lower one. But the sum of the energies stayed constant, proving that the photons remained entangled. More important, the team couldn't detect any time difference in the changes. "If there was any communication, it would have to have been at least 10,000 times the speed of light," says Dr. Gisin. "Because this is such an unlikely speed, the conclusion is there couldn't have been communication and so there is non-locality."
Right, so there is no common-sense explanation of quantum mechanics. About the encryption?
Some researchers are using the uncertain state of photons to solve real-world problems. When encrypting sensitive data such as a bank transfer, both the sending party and the receiving party must have the same key. The sender needs the key to hide the message and the receiver to reveal it. Since it isn't always practical to exchange keys in person, the key must be sent electronically, too. This means the key (and the messages) may be intercepted and read by an eavesdropper. An electronic key is usually written in the computer binary code of "ones" and "zeros." Quantum physics permits a more sophisticated approach. The same "ones" and "zeros" can now be encoded by using the properties of photons, like spin. If someone intercepts a photon-based message, the spins change. The receiver then knows the key has been compromised. MagiQ Technologies Inc. of Cambridge, Mass., refreshes its quantum keys as often as 100 times a second during a transmission, making it extremely hard to break. It sells its technology to banks and companies. Dr. Gisin is a founder of ID Quantique SA in Switzerland. The company's similar encryption tool is used by online lottery and poker firms to safely communicate winning numbers and winning hands. Votes cast in a recent Swiss federal election were sent in a similar way.
We live in a mysterious world, where uncertainty is better for security than certainty - but at the quantum level only. The person who left his keys stuck in the front door all night is one dumb bunny and can be grateful that most thieves wouldn't expect to get so lucky, which is why he was the first person to discover the problem in the morning.

Multiverse: Getting comfortable with a zillion of everything that is unique?

In "How to map the multiverse" (04 May 2009), Anil Ananthaswamy explains:
Greene's transformation is emblematic of a profound change among the majority of physicists. Until recently, many were reluctant to accept this idea of the "multiverse", or were even belligerent towards it. However, recent progress in both cosmology and string theory is bringing about a major shift in thinking. Gone is the grudging acceptance or outright loathing of the multiverse. Instead, physicists are starting to look at ways of working with it, and maybe even trying to prove its existence.

If such ventures succeed, our universe will go the way of Earth - from seeming to be the centre of everything to being exposed as just a backwater in a far vaster cosmos. And just as we are unable to deduce certain aspects of Earth from first principles - such as its radius or distance from the sun - we will have to accept that some things about our universe are a random accident, inexplicable except in the context of the multiverse.
Also
However, if our universe is part of a multiverse then we can ascribe the value of the cosmological constant to an accident. The same goes for other aspects of our universe, such as the mass of the electron. The idea is simply that each universe's laws of physics and fundamental constants are randomly determined, and we just happen to live in one where these are suited for life. "If not for the multiverse, you would have these unsolved problems at every corner," says Linde.


Let's see. We don't need to prove fine tuning. It's just there. But there's no evidence for the multiverse; it is an attractive idea because it makes our current cosmological values and fine tuning appear random. I love this line: " ... starting to look at ways of working with it, and maybe even trying to prove its existence".

Question: How fit are people in this state of mind to evaluate what they are seeing?

Podcast in the intelligent design controversy: origin of life

Origin of Life Chemistry Shows Intelligent Design

Click here to listen.

On this episode of ID the Future, Casey Luskin interviews Baylor University chemist Dr. Charles Garner on new findings in origin of life research and the plausibility of the chemical origin of life scenario. Listen in as Dr. Garner shows the speculation and imagination materialists employ to explain the origin of life.

For more information, read some of Dr. Garner's comments here at Evolution News & Views.

Those Evil Discos - eviller and eviller