Nobel Prize Spotlights Cosmic and Organic Asymmetries
Heads or tails have equal probabilities, so why
does nature sometimes prefer one over the other?
The Nobel Prize for Chemistry 2021 has been awarded to Benjamin List and David MacMillan for their discovery of organic catalysts that can more easily separate chiral molecules (Phys.org, New Scientist). Chirality refers to the “handedness” of many organic molecules that are mirror images of each other. Amino acids, for instance, come in so-called “left-handed” (L for levo) and right-handed (D for dextro) forms. In every way except geometry, these isomers are thermodynamically identical. All life, with few exceptions, has a uniform preference for left-handed amino acids and right-handed sugars. This asymmetry has long been a great mystery; how did it arise, and how is it maintained? Adding to that mystery is another one, mentioned in Nature‘s write-up on the Nobel award:
In a range of phenomena and at vastly different scales, nature often seems to prefer one handedness over another, Felser adds. This is reflected in the fact that matter predominates over antimatter in the Universe, and that life uses left-handed amino acids and right-handed sugars.
Why Asymmetry Matters
The asymmetry in biomolecules is functionally important. Without uniform L-amino acids, proteins would be unable to fold and function. Living cells have quality control systems to ensure that no wrong-handed building blocks get into the molecules needed for life. Another article on Phys.org says that the health disaster of birth defects from the use of thalidomide came about because the drug was a mixture of both hands; “it turned out that while one was effective, its mirror image counterpart was toxic.”
In a vastly different but related sense, the matter vs antimatter asymmetry is functionally important. Equal amounts of both would lead to collisions that would annihilate all matter in random bursts of deadly energy. If no matter, then no stars, no planets, no life.
The Origin of Asymmetry
The importance of molecular asymmetry is well established, but its origin is a mystery to believers in chemical evolution. Life needs single-handed building blocks, but unguided nature could not have provided them. Any naturally-produced building blocks would have been 50/50 blends of both hands, or racemic mixtures. Even if one could imagine a pure one-handed starting pool, they would racemize over time.
Before a working cell could ever form with the quality control to build uniformly-handed proteins, only mixed-handed polymers would be able to form in a chemical soup. Such a time before life, furthermore, would be unable to conjure up a success with natural selection (the Stuff Happens Law), given that natural selection—if it even worked—requires accurate replication. That, in turn, requires a genetic code with quality control, proteins and enzymes, and a sophisticated membrane to hold everything together.
It is unthinkable to imagine all these requirements being met by chance when even one small protein defies the probabilistic odds by many, many orders of magnitude (see “The Amoeba’s Journey” from the Illustra Media documentary Origin). For those unwilling to place such ridiculous bets on natural explanations, the only alternative is intelligent design.
A Gift of Nature?
The prize winners had no explanation for the asymmetry in biological molecules, but were glad they exist.
“Why in the world is biology single-handed? Why do we have this preference in nature? We don’t know,” List said. “This handedness is transferred in the catalytic reaction onto the substrates so that you get more of these handed molecules. It’s a great gift, I would say, that nature provides these molecules for us.”
“Chirality, for me, is the most interesting question in physics and chemistry and maybe even in biology,” Felser says, adding that today’s announcement could be “inspiring for the younger generations to look more for symmetry violations in nature”.
Big bang theory has no luck accounting for the matter/antimatter asymmetry either. Antimatter is functionally equivalent to matter; only the charge is different. Secular cosmological models predict equal quantities of both. The only explanation so far given is some unknown quantum-mechanical process might have created a slight excess of matter. All the rest annihilated itself, and our present universe is the result of the tiny fraction left over. This explanation sounds like special pleading to maintain a naturalistic world view.
Who is anti-science? Who is a fundamentalist? Who is too blinded by dogmatic adherence to a worldview to see the truth? It’s not creationists. They acknowledge the one necessary and sufficient cause to account for the observations of a functioning universe: an almighty Creator God, transcendent above nature, with the knowledge, wisdom and foresight to design and implement working systems according to a master plan. It was not a committee plan, either. “For thus says the Lord, who created the heavens (he is God!), who formed the earth and made it (he established it; he did not create it empty, he formed it to be inhabited!): “I am the Lord, and there is no other.'” (Isaiah 45:18).
The ones blinded by dogma are the ones who bet on futile odds that are beyond astronomically improbable: the origin of a universe where the asymmetries seen in matter and life worked out by chance. Paul’s warning in Romans 1 cannot be repeated too often. It explains how the smartest scientists in the most prestigious institutions around the world can come to such irrational beliefs.
18 For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who by their unrighteousness suppress the truth. 19 For what can be known about God is plain to them, because God has shown it to them. 20 For his invisible attributes, namely, his eternal power and divine nature, have been clearly perceived, ever since the creation of the world, in the things that have been made. So they are without excuse. 21 For although they knew God, they did not honor him as God or give thanks to him, but they became futile in their thinking, and their foolish hearts were darkened. 22 Claiming to be wise, they became fools, 23 and exchanged the glory of the immortal God for images resembling mortal man and birds and animals and creeping things.
24 Therefore God gave them up in the lusts of their hearts to impurity, to the dishonoring of their bodies among themselves, 25 because they exchanged the truth about God for a lie and worshiped and served the creature rather than the Creator, who is blessed forever! Amen.
There is hope even for them. They can turn around, and believe the good news offered by this Creator who is not only omniscient and omnipotent, but also merciful and gracious (John 3).