The Spooky
World Of Quantum Biology By: Michael
Garfield
The new science of
quantum biology is teaching us about how the actual behavior of evolution is
governed by disconcertingly spooky processes – time travel being one of them.
Will quantum computation finally be realized by biomimicry, in organic systems? Evolution is the new (old) computation…and
we’re about to take the reins.
World Of Quantum Biology |
One hundred and fifty
years ago, paleontologist Thomas Henry Huxley (an autodidact and philosopher
who coined the term “agnostic” and was known as “Darwin’s Bulldog” for his
passionate defense of natural selection) asserted that humankind would
eventually take the processes of evolution into our own hands. Within a few
decades of his proclamation, a cadre of equally brilliant scientists including
Werner Heisenberg, David Bohm, and Max Planck began to unravel the mysterious
properties of quantum mechanics. These two theories –- evolutionary and quantum
dynamics — can each be considered among the most important discoveries of all
time. Taken together, they have changed almost everything about the way we
understand reality. However, in spite of the popularity of interdisciplinary
research and unifying theories over the last hundred years (despite, even,
quantum physicist Erwin Schröedinger’s 1944 book, What Is Life?), it was only
recently that the relationship between these two vastly important domains was
even considered. Now, a new kind of science, called “quantum biology,” is
beginning to emerge –- and it could change everything we know, again..
The premise is
simple. Life is a molecular process; molecular processes operate according to
the quantum playbook; therefore, life is a quantum process. And yet, it wasn’t
until the nineties that anyone suggested biology could be better understood by
looking at it through the lens of quantum theory. (The seminal paper was D.V.
Nanopoulos’ "Theory of brain function, quantum mechanics and
superstrings.”) Not long after that, the
idea caught on – particularly in the neurosciences, where the idea of the brain
as a quantum computer quickly became a topic of fierce debate.
Quantum computation,
a science still in its infancy, promises swiftness and efficiency vastly
superior to anything possible with conventional silicon chips. Rather than
relying on binary bits like contemporary systems, quantum computers use
“qubits” that include all possible superpositions of a particle’s classical
state. Instead of being “trapped” in a single configuration, the logic gates of
a quantum computer employ multiple possibilities in synchrony – using the
entire set of alternative outcomes to arrive at an answer.
Scientists have recently
discovered that quantum energy transfers allow plants
and cynobacteria to convert sunlight into chemical energy nearly instantly, and with almost 100 percent efficiency. "As energy
passes between molecules involved in photosynthesis, a newly observed ‘wavelike
characteristic’ allows the energy to ‘simultaneously sample all the
potential energy pathways and choose the most efficient one,’" our worid science co-bloggers
observe. They liken it to the "sci-fi trope" in which "a digital
consciousness" is split "into several ‘forks’ that simultaneously
explore different courses of action before telling a central consciousness what
to do
It’s a promising
avenue for people with big plans for strong AI or virtual reality. The only
complication is that coherence –- in which the many possible states of a
particle or group of particles stay hung in superposition –- is something
scientists have only been able to study under extremely controlled conditions.
It’s only possible when that system doesn’t interact with anything else that
might “collapse the wave function,” and so most of the major options for
quantum computing involve impractical scenarios like creating a supercooled
vacuum.
This is one of the
reasons that many scientists have considered quantum biology both unlikely and
unscientific. The thermal noise of biological systems seemed too great to allow
for quantum weirdness; and even if it could, how on Earth would we study it? But science is the story of ingenuity’s
victory over shortsightedness – and one research team, led by Gregory S. Engel
at UC Berkeley, has devised way to directly detect and observe quantum-level
processes within a cell using high-speed lasers.
They were trying to
establish exactly how organic photosynthesis approaches 95% efficiency, whereas
the most sophisticated human solar cells operate at only half that. What they
discovered is nothing short of remarkable. Using femtosecond lasers to follow
the movement of light energy through a photosynthetic bacterial cell, Engel et
al. observed the energy traveling along every possible direction at the same
time. Instead of following a single trajectory like the electrons on a silicon
chip, the energy in photosynthesis explores all of its options and collapses
the quantum process only after the fact, retroactively “deciding” upon the most
efficient pathway.
What does this all
mean? Not only does quantum phenomena occur in living systems, but the basic
processes of life we take for granted rely on the transfer of information
backward in time. Life is so magical because it cheats.
Although the
mechanisms by which a living cell can prevent decoherence by dampening its own
chemical “noise” remain utterly mysterious, findings such as Engels’
conclusively demonstrate that room-temperature quantum computing is possible
(and knowing how something works isn’t always necessary in order to use it).
And Engel’s group isn’t the only team to detect it: other laboratories have
implicated a phenomenon called electron tunneling (micro-teleportation, in
which an electron disappears in one location and instantaneously appears
somewhere else without having traveled the intermediate distance) at work
behind a range of organic phenomena, from our sense of smell and the activities
of our enzymes to the neutralization of free radicals with anti-oxidants… possibly even consciousness itself. Paul
Davies (Arizona State University) and JohnJoe McFadden (The University of
Surrey) have independently suggested that computation in the netherworld of
quantum coherence might explain how the earliest self-replicating molecules
overcame the inestimable odds against them –- life’s very existence may be the
consequence and continued operation of a quantum computer. We may ultimately
have to accept our human quest for qubit calculation as a kind of biomimicry,
rather than something new and unique.
Quantum biology
stands to answer other big questions, as well –- questions that many
contemporary biologists prefer to ignore. McFadden, in his excellent primer
Quantum Evolution, cites several experiments that suggest certain mutations are
“intelligent,” even “anticipatory.” For
example, bacterial cultures have been observed to evolve clever responses to
lab toxins at speeds that – just like the emergence of DNA from a primordial
soup – defy astronomical odds. Can
biological quantum calculation account for this? McFadden thinks so. (His hypothesis was
itself anticipated in the science fiction of Greg Egan, whose novel Teranesia
featured some very “spooky” retrocausal mutations – including the instantaneous
appearance of entire new ecosystems via competing future evolutionary
scenarios. Whether such extreme examples of quantum biological principles are
possible remains to be seen.)
Quantum Computer |
As we continue to
probe biological phenomena that beat quantum computer scientists to the punch,
a new picture emerges of evolutionary computing and design. Huxley’s prophecy
that we will eventually take the reins of our own evolution might come true
sooner than predicted by establishment geneticists. But by appealing to the
quantum oracle, we may be acting in service of something far older and more
intelligent than we can even guess. Ultrafast computing, accelerated by our
explorations into the new science of quantum biology, could well be the
critical technology that pushes us over the edge into the Singularity – a
timeless and transcendent event in which we already live, because it is the
nature of life itself – a vast sentience beyond human comprehension, and we are
merely the newest avenue for its expression in the world. Classical or quantum,
human or ecological, natural selection still gets the last laugh.
Everywhere
in a Flash: The Quantum Physics of Photosynthesis
The Quantum Physics of Photosynthesis |
By
hitting single molecules with quadrillionth-of-a-second laser pulses,
scientists have revealed the quantum physics underlying photosynthesis, the
process used by plants and bacteria to capture light’s energy at efficiencies
unapproached by human engineers.
The
quantum wizardry appears to occur in each of a photosynthetic cell’s millions
of antenna proteins. These route energy from electrons spinning in
photon-sensitive molecules to nearby reaction-center proteins, which convert it
to cell-driving charges.
Almost no
energy is lost in between. That’s because it exists in multiple places at once,
and always finds the shortest path.
Molecular Pathway of Photosynthesis |
“The
analogy I like is if you have three ways of driving home through rush hour
traffic. On any given day, you take only one. You don’t know if the other
routes would be quicker or slower. But in quantum mechanics, you can take all
three of these routes simultaneously. You don’t specify where you are until you
arrive, so you always choose the quickest route,” said Greg Scholes, a
University of Toronto biophysicist.
Scholes’
findings, published Wednesday in Nature, are the strongest evidence yet for
coherence — the technical name for multiple-state existence — in photosynthesis.
Bacterial Photosynthesis |
he LH2 pigment-protein from Rhodopseudomonas acidophila. Views are parallel (left) and perpendicular (right) to the plane of the membrane. The protein scaffold comprises concentric cylinders of nine (inner), and nine ß (outer) polypeptides (teal and purple ribbons, respectively). The 18 B850 BChls (which absorb strongly at 850 nm) are shown as spheres, in alternating red and orange, and the nine B800 BChls (which absorb strongly at 800 nm) are shown as green sticks (with the central Mg shown as a sphere). The macrocycles of the B850 and B800 BChls are arranged perpendicular and parallel, respectively, to the plane of the membrane. The figure was constructed using using Protein Data Bank (PDB) file 1NKZ (Papiz et al., 2003).
Two years
ago, researchers led by then-University of California at Berkeley chemist Greg
Engel found coherence in the antenna proteins of green sulfur bacteria. But
their observations were made at temperatures below minus 300 degrees
Fahrenheit, useful for slowing ultrafast quantum activities but leaving open
the question of whether coherence operates in everyday conditions.
The
Nature findings, made at room temperature in common marine algae, show that it
does. Moreover, similar results from an experiment on another, simpler
light-harvesting structure, announced by Engel’s group last Thursday on the
pre-publication online arXiv, suggest that photosynthetic coherence is routine.
The
findings are wondrous in themselves, adding a new dimension to something taught
— incompletely, it now seems — to every high school biology student. They also
have important implications for designers of solar cells and computers, who
could benefit from quantum physics conducted in nonfrigid conditions.
“There’s
every reason to believe this is a general phenomenon,” said Engel, now at the
University of Chicago. He called Scholes’ finding “an extraordinary result”
that “shows us a new way to use quantum effects at high temperatures.”
Scholes’
team experimented on an antenna protein called PC645, already imaged at the
atomic scale in earlier studies. That precise characterization allowed them to
target molecules with laser pulses lasting for one-quadrillionth of a second,
or just long enough to set single electrons spinning.
By
analyzing changes to a laser beam sent through the protein immediately
afterwards, the researchers were able to extrapolate what was happening inside
— an ultra-high-tech version of shadows on a screen. They found that energy
patterns in distant molecules fluctuated in ways that betrayed a connection to
each other, something only possible through quantum coherence.
“It’s the
same as when you hit two tuning forks at the same time, and hear a low-pitched
oscillation in the background. That’s the interference of sound waves from the
forks. That’s exactly what we see,” said Scholes.
According
to Scholes, the physics of photosynthetic proteins will be further studied and
used to improve solar cell design. Engel suggested their use in long-promised
but still-unworkable quantum computing. “This allows us to think about
photosynthesis as non-unitary quantum computation,” he said.
Quantum-physical
processes have been observed elsewhere in the biological realm, most notably in
compass cells that allow birds to navigate by Earth’s geomagnetic fields.
Researchers have also proposed roles for quantum physics in the animal sense of
smell and even in the brain. Engel predicts the emergence of an entire field of
quantum biology.
“There
are going to be some surprises,” said Scholes. “Who knows what else there is to
discover?”
Reverse-Engineering
the Quantum Compass of Birds
Quantum Compass of Birds |
Scientists
are coming ever closer to understanding the cellular navigation tools that
guide birds in their unerring, globe-spanning migrations.The latest piece of
the puzzle is superoxide, an oxygen molecule that may combine with
light-sensitive proteins to form an in-eye compass, allowing birds to see
Earth’s magnetic field.
“It
connects from the subatomic world to a whole bird flying,” said Michael Edidin,
an editor of Biphysical Journal, which published the study last week. “That’s
exciting!”The superoxide theory is proposed by Biophysicist Klaus Schulten of
the University of Illinois at Urbana-Champaign, lead author of the study and a
pioneer in avian magnetoreception. Schulten first hypothesized in 1978 that
some sort of biochemical reaction took place in birds’ eyes, most likely
producing electrons whose spin was affected by subtle magnetic gradients.
In 2000,
Schulten refined this model, suggesting that the compass contained a
photoreceptor protein called cryptochrome, which reacted with an
as-yet-unidentified molecule to produce pairs of electrons that existed in a
state of quantum entanglement — spatially separated, but each still able to
affect the other.
According
to this model, when a photon hits the compass, entangled electrons are
scattered to different parts of the molecule. Variations in Earth’s magnetic
field cause them to spin in different ways, each of which leaves the compass in
a slightly different chemical state. The state alters the flow of cellular
signals through a bird’s visual pathways, ultimately resulting in a perception
of magnetism.
Avian Compass Experiment : Published in Nature |
Far-fetched
as it sounds, subsequent research from multiple groups has found cellular
evidence of such a system. Molecular experiments suggest that it’s indeed
sensitive to Earth’s geomagnetics, and computational models suggest a level of
quantum entanglement only dreamed of by physicists, who hope to use entangled
electrons to store information in quantum computers.
Birds Flight |
But
though cryptochrome is likely part of the compass, the other part is still
unknown. In April, another group of magnetoreception researchers showed that
oxygen could interact with cryptochrome to produce the necessary electron
entanglements. Schulten’s latest proposed role for superoxide, an oxygen anion
found in bird eyes, fits with their findings.Edidin cautioned that “this is
still not an experimental demonstration. It’s a possibility.”As for the
perceptual result of the compass, it remains a mystery. Some researchers think
birds might see a dot at the edge of their vision, swiveling according to the
direction they’re facing. Others think it might produce effects of color or
hue. Perhaps migrating birds fly towards the light.
Google
Earth Reveals Sixth Sense of Cattle, Deer
Sixth Sense of Cattle, Deer |
Though my
farm-raised father insists differently, there’s something a bit spooky about
cows standing in a field. They’re just a bit too placid; I’ve always suspected
that those limpid eyes hide strange secrets.And what do you know — I was right!
German and Czech biologists have shown that cattle, along with deer,
instinctively stand in a north-south direction. They appear to possess a sixth
sense of magnetism.After studying Google Earth satellite images of cattle
herds, along with their own observations of roe deer, the researchers realized
that the animals routinely stood along a north-south axis."The magnetic
field is the only common and most likely factor responsible for the observed
alignment," write the researchers in a study published today in the
Proceedings of the National Academy of Sciences. "Our analysis … clearly
provides the crucial proof in favor of the Earth’s magnetic field being the
responsive cue."
They
think the ability evolved to help guide the animals’ ancestors during
migrations (which could explain why the results are stronger in deer than
cattle, which having been domesticated and restrained no longer migrate.)
What’s the physiological mechanism? That’s not yet known. "Our findings …
challenge neuroscientists and biophysics to explain the proximate
mechanisms," the researchers write.You hear that, neuroscientists and
biophysics? You got served!
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