Michael J. Behe's Blog, page 23

From EurekAlert: Meteorites plus gamma rays could have given Earth the building blocks for life

Even as detailed images of distant galaxies from the James Webb Space Telescope show us more of the greater universe, scientists still disagree about how life began here on Earth. One hypothesis is that meteorites delivered amino acids — life’s building blocks — to our planet. Now, researchers reporting in ACS Central Science have experimentally shown that amino acids could have formed in these early meteorites from reactions driven by gamma rays produced inside the space rocks.

Ever since Earth was a newly formed, sterile planet, meteorites have been hurtling through the atmosphere at high speeds toward its surface. If the initial space debris had included carbonaceous chondrites — a class of meteorite whose members contain significant amounts of water and small molecules, such as amino acids — then it could have contributed to the evolution of life on Earth. However, the source of amino acids in meteorites has been hard to pinpoint. In previous lab experiments, Yoko Kebukawa and colleagues showed that reactions between simple molecules, such as ammonia and formaldehyde, can synthesize amino acids and other macromolecules, but liquid water and heat are required. Radioactive elements, such as aluminum-26 (26Al) — which is known to have existed in early carbonaceous chondrites — release gamma rays, a form of high-energy radiation, when they decay. This process could have provided the heat needed to make biomolecules. So, Kebukawa and a new team wanted to see whether radiation could have contributed to the formation of amino acids in early meteorites.

The researchers dissolved formaldehyde and ammonia in water, sealed the solution in glass tubes and then irradiated the tubes with high-energy gamma rays produced from the decay of cobalt-60. They found that the production of α-amino acids, such as alanine, glycine, α-aminobutyric acid and glutamic acid, and β-amino acids, such as β-alanine and β-aminoisobutyric acid, rose in the irradiated solutions as the total gamma-ray dose increased. Based on these results and the expected gamma ray dose from the decay of 26Al in meteorites, the researchers estimated that it would have taken between 1,000 and 100,000 years to produce the amount of alanine and β-alanine found in the Murchison meteorite, which landed in Australia in 1969. This study provides evidence that gamma ray-catalyzed reactions can produce amino acids, possibly contributing to the origin of life on Earth, the researchers say.

EurekAlert!

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At Evolution News: Your Intelligently Designed Body Is a System of Systems

This excerpt from Your Designed Body, the new book by engineer Steve Laufmann and physician Howard Glicksman. Surely, the interdependent functionality of the human body stands as evidence of design.

Howard Glicksman and Steve Laufmann write:

To be alive, every cell in your body needs solutions to a complicated set of problems — containment, gates, controls, framing, transport, energy, information, and reproduction. Zooming out from a single cell, the human body as a whole is made up of around thirty trillion cells (a figure that varies widely with an individual’s size). It needs to solve all the same kinds of problems that a cell does, plus quite a few more. And it needs new ways to solve old problems, ways completely different from how the same problems were solved at the cellular level. 

For example, a single-celled organism is like a microscopic island of life. The cell gets what it needs and gets rid of what it doesn’t need from its surrounding environment. In contrast, a large multi-cellular organism (like you) is more like a continent with a deep and dark interior. Most of the cells reside deep in the interior with no direct access to the body’s surrounding environment. For a multicellular organism, then, harvesting the raw materials its cells need and getting rid of toxic by-products becomes a major logistical problem.

Photo credit: AJ Jean via Unsplash.

Several hundred such problems must be solved for a complex body to be alive. And many of the solutions to these basic problems generate new problems that must also be solved, or that constrain other solutions in critical ways. The result is that for a complex body to be alive, thousands of deeply interconnected problems must be solved, and many of them solved at all times, or life will fail.

Additionally, many of the problems the body faces are much more complex than those solved in any individual cell. For example, while it takes impressive engineering for cells to sense their environment (a process not well understood), sensing poses a considerably greater engineering challenge for a human body, since it involves much more sophisticated forms of sensing — like vision, hearing, taste, smell, and the fine-touch sensing in your hands.

The bottom line is that, as hard as it is for a cell to maintain life, it’s much harder for an organism with a complex body plan like yours.

Hard Problems Take Clever Solutions

Together, the many thousands of problems the body must solve for survival and reproduction require many thousands of ingenious solutions. Most of these solutions need special-purpose equipment across all levels of the body plan, from specifically adapted molecular machinery (like hemoglobin molecules) to specialized cells (like red blood cells) to tissues (like bone marrow) to whole body systems (like the cardiovascular system). This may involve hundreds of thousands of parts, replicated in millions of places. 

Solutions to this class of problems always exhibit four interesting characteristics:

1. Specialization

It takes the right parts to make a working whole. Each part must perform a function with respect to the larger system. Each part must be made of the right materials, fine-tuned to precise tolerances, and equipped with suitable interfaces with the other parts. This is a design principle known as separation of concerns. Virtually every designed object in human experience is based on this design strategy. And this appears to be equally true in biological systems, including virtually every capability in the human body.

2. Organization

The parts must be in the right places, arranged and interconnected to enable the function of the whole. Each part must work with the other parts in an integrated way. The parts are often made of different materials, where a material is chosen for how its particular properties support the specific needs of that particular part and how it must function in light of the whole. This is a design principle known as the rule of composition. It counterbalances the separation of concerns principle. Separation of concerns breaks large problems into subproblems that are (slightly) easier to solve, while the rule of composition puts the solutions to the subproblems (the parts) together such that the function of the whole is achieved.

3. Integration

The parts must have exactly those interfaces that enable the parts to work together. With bones, this obviously involves their shapes, especially at their connection and articulation points (the joints). For other body systems this can involve structural support, alignment, shock absorption, gating and transport systems, electrical signaling, chemical signaling, exchange of complex information, and integrated logic.

4. Coordination

The parts must be coordinated such that each performs its respective function or functions at the right time. This usually requires one or more control systems, either active or passive, and usually some form of sensing and communication between the parts and the controls. This property is achieved by orchestration or choreography, which differ in the ways the controls are achieved, the former by a more centralized approach and the latter by a more distributed approach. In an old Chevy pickup, this function for the engine is achieved by a camshaft. In ATP Synthase, this is also achieved by a camshaft.

In designing a complex system, all four of the above factors must be considered across the whole when designing each of the parts.

When a system has all the right parts, in all the right places, made of the right materials, with the right specifications, doing their respective functions, at all the right times, to achieve an overall, system-level function that none of the parts can do on its own, you have what is known as a coherent system. Coherence, in this sense, is a functional requirement for all non-trivial systems. Moreover, in life the systems are never standalone — there are always interdependencies between and among the various component systems and parts. The human body is composed of coherent, interdependent systems.

The Scope of the Body’s Solutions

It takes a lot of work to keep a sawmill running. Logs need to be obtained, sorted, and brought in. Cut lumber needs to be taken away for further processing. The motors need electricity. The saw blades need to be changed out and sharpened. The workers need coffee. Lots of coffee. All these require various systems within the larger system.

Similarly, to keep your cells alive and working properly, your body requires eleven major organ systems1 to distribute, dispose, defend, generate energy, and perform other crucial tasks. The systems and their roles:

The respiratory system takes in the oxygen (O2) your cells need and gets rid of excess carbon dioxide (CO2).The gastrointestinal (digestive) system takes in the water, sugar, fat, protein, salt, vitamins, and minerals your cells need.The renal/urinary system rids your body of excess nitrogen (ammonia, urea) and helps maintain your blood pressure and control your body’s water and salt content.The cardiovascular system pumps blood throughout your body to provide “just in time” delivery of supplies to every organ no matter what you’re doing. It’s also critical for managing temperature, dissipating excess heat, and distributing chemical signals throughout the body.The integumentary system (skin) protects your body from the outside world while helping control your temperature through sweating. It continually replenishes itself from the inside out and is remarkably good at repairing itself when it gets cut or scraped.The skeletal system (bones) provides support and protection for many of your vital organs (like your brain, spinal cord, lungs, and heart) and is the framework for the muscles. Its structures, organization, and proportions enable an amazing range of movement and activity.The motor system (muscles) allows the body to move around, stay balanced, and handle things. It’s capable of a wide range of strength demands yet possesses extraordinarily fine controls.The nervous system (nerves and brain) allows the body to sense your surroundings, maintain your body’s vital functions, and control your activities. It also allows you to be awake and aware — to think, communicate, imagine, and create.The immune/lymphatic system protects you from invading pathogens.The endocrine system sends out hormones to regulate things like your metabolism and growth.The reproductive system, male and female, enables new human life.

Each of these is a specialized subsystem in the body. The body needs all of them, organized properly, and coordinated to remarkably fine tolerances. In turn, each of these subsystems is a complete system, itself composed of many specialized subsystems and parts, organized in specific ways, and precisely coordinated.

See Evolution News.

Natural processes tend to destroy information-rich, functional systems over time. The body’s remarkable hierarchy of interdependent life-support systems stands as the most unnatural physical phenomenon in the universe.

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Wednesday Night (12/7): See Mars Disappear Behind the Moon

Astronomer Jeffrey Bennett writes:

A really cool astronomical event is coming up on Wednesday night (Dec. 7): Mars will disappear behind the Moon. This event, called an “occultation,” is essentially the same as an eclipse, in which one object passes in front of another as seen from Earth. In this case, because Mars moves very slowly relative to the stars in our sky while the Moon moves at a rate of about half a degree per hour (that is, it moves by about its own angular diameter each hour relative to the stars), it is actually the Moon that will be passing in front of Mars. 

This particular occultation will be especially cool because it is happening when Mars is at opposition (directly opposite the Sun in our sky) and the Moon is full, so both objects are at their brightest. (Most occultations do not occur with these special circumstances, so this is a lucky coincidence for this particular one.)  Sky and Telescope put out a great summary of how to watch this event, from which I’ve extracted these key points:

The occultation of Mars will be visible to anyone in the swath shown on the map below, which means most of the United States, Canada, and Europe. If you are outside this swath, you will still see Mars close to the Moon, but it won’t pass directly behind it. Be sure you watch on the correct night: It is the NIGHT of Wednesday, Dec. 7. This means after dark on Dec. 7 for those watching in North America, and pre-dawn on Dec. 8 for those in Europe. If you have clear skies, it will be very easy to spot the Moon and Mars throughout the night, since they’ll be close together and very bright. But to see Mars disappear behind the Moon (and reappear later), you’ll need to look at just the right times. The table below lists times for selected cities; for other locations, you can make an estimate based on the times for cities near you, or check this page from the International Occultation Timing Association with a much more complete listing (note that times on that page are UT [also called UTC or GMT], meaning time in Greenwich, England, so be sure to convert to local time). Again, note that these times are after dark on Wednesday (Dec. 7), which for Europe means the pre-dawn of Dec. 8.  CityDisappearanceReappearanceLos Angeles, CA6:30 p.m. PST7:30 p.m. PSTSeattle, WA6:52 p.m. PST7:51 p.m. PSTVancouver, BC6:55 p.m. PST7:52 p.m. PSTPhoenix, AZ7:32 p.m. MST8:31 p.m. MSTDenver, CO7:45 p.m. MST8:48 p.m. MSTSt. Louis, MO9:06 p.m. CST9:52 p.m. CSTChicago, IL9:11 p.m. CST10:05 p.m. CSTToronto, ON10:29 p.m. EST11:18 p.m. ESTLondon, UK4:58 a.m. GMT5:59 a.m. GMTStockholm, SE5:54 a.m. CET6:43 a.m. CETParis, FR6:04 a.m. CET7:02 a.m. CETMadrid, ES6:21 a.m. CET7:07 a.m. CETYou don’t need any equipment to see this event, as it will be easily visible to the naked eye. However, you’ll be able to watch with more detail if you have a pair of binoculars or a telescope. 

Additional note:

It’s a complete coincidence that just as Mars reaches its biggest, brightest and best for 26 months it will be occulted—eclipsed—by the full Moon.

Forbes.com

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At Reasons.org: Is the Universe the Way It Is Because It’s the Only Way It Could Be?

Reasons.org

Hugh Ross writes:

Question of the week: How do you respond to the argument against fine-tuning as evidence for God by those who say the universe and its laws of physics are the way they are because that’s the only way they could be?

My answer: As I have documented in my books, The Creator and the Cosmos, 4th edition, Improbable Planet, and Designed to the Core, there are hundreds of independent features of the universe, its laws of physics, and its space-time dimensions that must be exquisitely fine-tuned to make the existence of humans, or their equivalent, possible in the universe. However, that pervasive fine-tuning is not the only way the universe and the laws of physics could be.

From a biblical perspective, the angelic realm has different dimensions and different laws of physics. Similarly, the future home of Christians, the new creation (see Revelation 21–22) has different dimensions and different laws of physics. Readers can see our book, Lights in the Sky and Little Green Men, for the scientific physical evidence for angels and the angelic realm.

As I explain in my books on fine-tuning, the universe can be fine-tuned in a different way to allow for the existence of certain kinds of bacteria but not allow for the existence of animals and humans. I also show how the laws of physics can remain unchanged but the universe structured so that no physical life is possible anywhere, anytime in the universe.

As I demonstrate in Designed to the Core, it is not just the laws of physics and the universe as a whole that are fine-tuned to make the existence of humans possible. All the universe’s subcomponents, from those on the largest size scales to those on the smallest size scales must be fine-tuned for humans to possibly exist.

Unlike the universe, the observed sample size of the universe’s subcomponents is not one. For example, there are a trillion trillion stars in the observable universe. So far, however, astronomers have detected only one star, our Sun, that possesses the fine-tuned history and features that make it possible for the existence of humans on a planet orbiting it. The Sun is not the only way stars can be. The same argument can be made for our Laniakea Supergalaxy Cluster, our Virgo Cluster of galaxies, our Local Group of galaxies, our Milky Way Galaxy, our local spiral arm, our Local Bubble, our planetary system, our planet, and our moon. The fine-tuning of the universe and all its subcomponents also vary according to the intended purposes for humans. As I show in Why the Universe Is the Way It Is, Improbable Planet, and Designed to the Core, the fine-tuning that allows billions of humans on one planet to be redeemed from their sin and evil within a time span of several tens of thousands of years is orders of magnitude more constrained than the fine-tuning that allows for the existence of a tiny population of technology-free humans with lifespans briefer than 30 years.  

Reasons.org

Dr. Ross refers to scientific observations that show evidence of fine-tuning, not just for the existence of life, but to sustain life as we know it on Earth, with millions of species of plant and animal life, and a multi-billion population of humans with a technologically advanced global civilization. Often, arguments against intelligent design boil down to bad theology. Dr. Ross provides here a very brief connection between physical design parameters and a biblically-based theology.

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From Live Science: Search for alien life just got 1,000 times bigger after new telescope joins the hunt

Harry Baker writes:

One of the world’s largest telescopes has just joined the hunt for signs of alien life elsewhere in the cosmos.

A pair of dishes from the MeerKAT telescope in South Africa. The night sky has been overlaid with radio bubbles observed by the telescope. Image credit: South Africa Radio Astronomy Observatory (SARAO).

Since 2016, the Breakthrough Listen project has been quietly using radio telescopes to listen for unusual radio signals, or technosignatures, from potential advanced extraterrestrial civilizations within the Milky Way. The project, launched in part by the late Stephen Hawking and funded by Israeli entrepreneur Yuri Milner, already uses the Green Bank Telescope (GBT) in West Virginia in the United States and the Parkes Telescope in New South Wales, Australia, as well as other radio telescopes from across the globe, to scan nearby stars. But now, the MeerKAT Telescope — an array of 64 individual dishes in South Africa, and currently the largest radio telescope in the Southern Hemisphere — has joined the party. 

After more than two years of integrating their programs into the MeerKAT system, Breakthrough Listen scientists have finally started using data collected by the array of dishes to look for unusual signals from nearby stars, according to a statement released Dec. 1.

The inclusion of MeerKAT will “expand the number of targets searched by a factor of 1,000,” Breakthrough Listen representatives wrote in the statement. This will greatly increase the chances of detecting a technosignature, if there are any out there to be found, they added. 

MeerKAT drastically improves the number of targets that Breakthrough Listen can analyze because its dishes can lock onto up to 64 different targets at once, while other telescopes can only focus on one at a time.

“MeerKAT can see an area of the sky 50 times bigger than the GBT can view at once,” Andrew Siemion, principal investigator of Breakthrough Listen and director of the University of California Berkeley’s Search for Extraterrestrial Intelligence (SETI) Research Center, said in the statement. “Such a large field of view typically contains many stars that are interesting technosignature targets.” 

Breakthrough Listen will access a continuous datastream from MeerKAT without interfering with scheduled astronomical research. Instead, data collected from other studies will be fed into a supercomputer, which uses a special algorithm to scan signals that it does not recognize as coming from known cosmic phenomena such as pulsars, stellar flares or supernovas. When a strange signal is detected, a researcher can then analyze the signal. 

Using MeerKAT, Breakthrough Listen will be able to scan more than 1 million stars during the next two years, which is “very exciting,” Cherry Ng, an astrophysicist at the University of Toronto and a project scientist at Breakthrough Listen, said in the statement. 

One of the first stars that will investigated in more detail by MeerKAT and Breakthrough Listen will be Proxima Centauri, the nearest star to our solar system, which has two exoplanets that lie within the star’s habitable zone, researchers said. 

In June, Chinese astronomers using the enormous “Sky Eye” telescope in Guizhou, China — the largest radio telescope on Earth — announced that they had detected a possible alien signal. But this was quickly debunked by one of the study authors who revealed the signal was almost definitely human radio interference.  

Live Science

It’s clear that these researchers believe that they can distinguish between a radio signal produced by an intelligent being and a radio signal produced by natural causes. Why should the design in living organisms not stand as evidence that biological design is produced by an intelligent source of ultimately supernatural origin? If you say, “We know that natural processes can produce the design seen in living systems,” I’m afraid that you are mistaken.” If you say, “We know that there is nothing beyond nature,” then you are mouthing words without knowledge.

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At Phys.org: How giant-faced owls snag voles hidden in snow

Hovering over a target helps giant-faced Great Gray owls pinpoint prey hidden beneath as much as two feet of snow.

The face of a great gray owl. Credit: James Duncan

Several of the owls’ physical features, especially parts of their wings and face, help them correct for sonic distortions caused by the snow, enabling them to find their moving food with astonishing accuracy, according to a new UC Riverside study.

While most owls fly straight at their prey, this species hovers just above a target area before dropping straight down and punching through the snow with its talons.

“These aren’t the only birds to hunt this way, but in some ways, they are the most extreme because they can locate prey so far beneath the snow cover,” said UC Riverside biologist Christopher Clark, who led the study. “This species is THE snow hunting specialist.”

A key finding relates to the owls’ broad disc-like face, which they use like radar to find food. The fleshy part of our ears works the way their facial features do. An opening under their feathers funnels sound toward their ears, which are located near the center of their faces.

“It’s similar to the way a dog can turn its ears to tune sound. Owls can do the same thing,” Clark said.

Bigger facial discs are more sensitive to low-frequency sounds. With the largest facial disc of any bird, great gray owls are built for hunting voles, their preferred food. Often mistaken for mice, voles have high-pitched voices that get lost under snow cover. However, their digging and chewing sounds beam straight onto the owls’ facial radar.

“The fact that low frequency sound passes through snow explains the facial disc of this species, because they have better low frequency hearing with such a big disc.”

Note: The owls’ broad disc-like face, allows them to hear the low frequency sounds of a vole. OK, this is a scientific conclusion. To assume that this “explains” the facial disc of this owl species is not science, it lacks any explanatory power and it is simply paying lip-service to the evolutionary story-line

The group’s sonic experiments also demonstrated that snow bends the voles’ sounds, creating an “acoustic mirage,” which could lead owls astray. By spending a moment directly above their prey, the birds correct for the snow’s distortions.

Great gray owls also have wings that appear to dampen the sound of flying, which may allow them to concentrate on the noises coming from the voles. Among all owls, this species is among the quietest in flight, owing to long, fringed wings coated in thick “velvet.” The sound-dampening qualities of these wings may be particularly useful during the hovering phase of the hunt.

This last aspect of the work is of interest not only to those fascinated by owls, but also to those developing quieter machines.

“Between the 1940s and 60s, airplane sounds dropped dramatically, but since then planes haven’t gotten much quieter. Studying how these owls‘ wings function could help inspire new planes and drones that create less noise,” Clark said.

Full article at Phys.org.

The sophisticated hunting “equipment” possessed by the Great Gray owl can provide inspiration for avionic engineers. Is there evidence for intelligent design in nature?

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At Big Think: Max Planck and how the dramatic birth of quantum physics changed the world

Marcelo Gleiser writes:

KEY TAKEAWAYS

Quantum physics was a radical departure from the classical physics of Newton. The quantum world is one in which rules that are completely foreign to our everyday experience dictate bizarre behavior. Even one of its first discoverers, Max Planck, was reluctant to back the radical conclusions his research led him to. 

We now live in the digital era. The scape of technological marvels that surrounds us is something we owe to 100 or so physicists who, at the dawn of the 20th century, were trying to figure out how atoms worked. Little did they know what their courageous, creative thinking would become a few decades later. 

The quantum revolution was a very hard process of letting go of old ways of thinking, ways that had framed science since Galileo and Newton. These habits were firmly rooted in the notion of determinism — simply put, scientists held that physical causes have predictable effects, or that nature follows a simple order. The ideal behind this worldview was that nature made sense, that it obeyed rational rules, like clocks do. Letting go of this way of thinking took tremendous intellectual courage and imagination. It is a story that needs to be told many times over.

Unpredictable radiation

The quantum era was the result of a series of laboratory discoveries during the second half of the 19th century that refused to be explained by the prevalent classical worldview, a view based on Newtonian mechanics, electromagnetism, and thermodynamics (the physics of heat). The first problem seems easy enough: Heated objects emit radiation of a certain kind. For example, you emit radiation in the infrared spectrum, because your body temperature hovers around 98° F. A candle glows in the visible spectrum because it is hotter. The question then is to figure out the relation between the temperature of an object and its glow. To do this in a simplified way, physicists studied not hot objects in general, but what happens to a cavity when it is heated up. And that’s when things got weird.

The problem they described came to be known as black-body radiation, the electromagnetic radiation trapped inside a closed cavity. Black-body here simply means an object that produces radiation on its own, without anything coming in. Studying the properties of this radiation by poking a hole in the cavity and studying the radiation that leaked out, it became clear that the shape and material of the cavity do not matter. All that matters is the temperature inside the cavity. Since the cavity is hot, atoms from its walls will produce radiation that will fill the space. 

The physics of the time predicted that the cavity would be filled mostly with highly energetic, or high-frequency, radiation. But that was not what the experiments revealed. Instead, they showed that there is a distribution of electromagnetic waves inside the cavity with different frequencies. Some waves dominate the spectrum, but not the ones with the highest or lowest frequencies. How could this be?

A quantum pint

The problem inspired the German physicist Max Planck, who wrote in his Scientific Autobiography that, “This [experimental result] represents something absolute, and since I had always regarded the search for the absolute as the loftiest goal of all scientific activity, I eagerly set to work.” 

Planck struggled. On Oct. 19, 1900, he announced to the Berlin Physical Society that he had obtained a formula that nicely fitted the results of the experiments. But finding the fit was not enough. As he wrote later, “On the very day when I formulated this law, I began to devote myself to the task of investing it with a true physical meaning.” Why this fit and not another one?

In working to explain the physics behind his formula, Planck was led to the radical assumption that atoms do not give radiation away continuously, but in discrete multiples of a fundamental amount. Atoms deal with energy as we deal with money, always in multiples of a smallest quantity. One dollar equals 100 cents, and ten dollars equals 1,000 cents. All financial transactions in the U.S. are in multiples of a cent. For the black-body radiation with its many waves of different frequencies, each frequency released relates to a minimum proportional “cent” of energy. The higher the frequency of the radiation, the larger its “cent.” The mathematical formula for this “minimum cent” of energy reads E = hf, where E is the energy, f is the frequency of the radiation, and h is Planck’s constant. 

Planck found its value by fitting his formula to the experimental black-body curve. Radiation of a particular frequency can only appear as multiples of its fundamental “cent,” which he later called quantum, a word that in late Latin meant a portion of something. As the great Russian-American physicist George Gamow once remarked, Planck’s hypothesis of the quantum created a world in which you could either drink a pint of beer or no beer at all, but nothing in between. 

Quantum blindness

Planck was far from happy with the consequences of his quantum hypothesis. In fact, he spent years trying to explain the existence of a quantum of energy using classical physics. He was a reluctant revolutionary, forcefully led by a deep sense of scientific honesty to propose an idea he was not comfortable with. As he wrote in his autobiography: 

“My futile attempts to fit the… quantum… somehow into the classical theory continued for a number of years, and they cost me a great deal of effort. Many of my colleagues saw in this something bordering on a tragedy. But I feel differently about it… I now knew that the… quantum… played a far more significant part in physics than I had originally been inclined to suspect, and this recognition made me see clearly the need for the introduction of totally new methods of analysis and reasoning in the treatment of atomic problems.” 

Planck was right. The quantum theory he helped propose evolved into an even deeper departure from the old physics than Einstein’s theory of relativity. Classical physics is based on continuous processes, such as planets orbiting the Sun or waves propagating on water. Our whole perception of the world is based on phenomena that continuously evolve in space and time. 

The world of the very small works in a completely different way. It is a world of discontinuous processes, a world where rules alien to our everyday experience dictate bizarre behavior. We are effectively blind to the radical nature of the quantum world. The energies we commonly deal with contain such an enormous number of energy quanta, that its “graininess” obscures our ability to see it. It is as if we lived in a world of billionaires, where a cent is a perfectly negligible amount of money. But in the world of the very small, the cent, or the quantum, rules. 

Planck’s hypothesis changed physics, and eventually the world. He could not have predicted this. Neither could Einstein, Bohr, Schrodinger, Heisenberg, and the other quantum pioneers. They knew they had hit on something different. But no one could have anticipated how far the quantum would change the world.

Big Think

The revelation of the quantum nature of physical reality is consistent with the understanding that information may be more fundamental than matter and energy.

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At Science Daily: Fossil overturns more than a century of knowledge about the origin of modern birds

Fossilised fragments of a skeleton, hidden within a rock the size of a grapefruit, have helped upend one of the longest-standing assumptions about the origins of modern birds.

Researchers from the University of Cambridge and the Natuurhistorisch Museum Maastricht found that one of the key skull features that characterises 99% of modern birds — a mobile beak — evolved before the mass extinction event that killed all large dinosaurs, 66 million years ago.

This finding also suggests that the skulls of ostriches, emus and their relatives evolved ‘backwards’, reverting to a more primitive condition after modern birds arose.

Using CT scanning techniques, the Cambridge team identified bones from the palate, or the roof of the mouth, of a new species of large ancient bird, which they named Janavis finalidens. It lived at the very end of the Age of Dinosaurs and was one of the last toothed birds to ever live. The arrangement of its palate bones shows that this ‘dino-bird’ had a mobile, dexterous beak, almost indistinguishable from that of most modern birds.

For more than a century, it had been assumed that the mechanism enabling a mobile beak evolved after the extinction of the dinosaurs. However, the new discovery, reported in the journal Nature, suggests that our understanding of how the modern bird skull came to be needs to be re-evaluated.

Each of the roughly 11,000 species of birds on Earth today is classified into one of two over-arching groups, based on the arrangement of their palate bones. Ostriches, emus and their relatives are classified into the palaeognath, or ‘ancient jaw’ group, meaning that, like humans, their palate bones are fused together into a solid mass.

All other groups of birds are classified into the neognath, or ‘modern jaw’ group, meaning that their palate bones are connected by a mobile joint. This makes their beaks much more dexterous, helpful for nest-building, grooming, food-gathering, and defence.

“This assumption has been taken as a given ever since,” said Dr Daniel Field from Cambridge’s Department of Earth Sciences, the paper’s senior author. “The main reason this assumption has lasted is that we haven’t had any well-preserved fossil bird palates from the period when modern birds originated.”

Two of the key characteristics we use to differentiate modern birds from their dinosaur ancestors are a toothless beak and a mobile upper jaw. While Janavis finalidens still had teeth, making it a pre-modern bird, its jaw structure is that of the modern, mobile kind.

“Evolution doesn’t happen in a straight line,” said Field. “This fossil shows that the mobile beak — a condition we had always thought post-dated the origin of modern birds, actually evolved before modern birds existed. We’ve been completely backwards in our assumptions of how the modern bird skull evolved for well over a century.”

The researchers say that while this discovery does not mean that the entire bird family tree needs to be redrawn, it does rewrite our understanding of a key evolutionary feature of modern birds.

Full article at Science Daily.

Assumptions seem to have played a large role in the evolutionary story of birds. When assumptions turn out to not match reality, then either the theory is wrong, or extrapolations made from the theory are unjustified.

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ITER: International Thermonuclear Experimental Reactor

ITER (“The Way” in Latin) is one of the most ambitious energy projects in the world today.

ITER, under construction.

In southern France, 35 nations* are collaborating to build the world’s largest tokamak, a magnetic fusion device that has been designed to prove the feasibility of fusion as a large-scale and carbon-free source of energy based on the same principle that powers our Sun and stars.
The experimental campaign that will be carried out at ITER is crucial to advancing fusion science and preparing the way for the fusion power plants of tomorrow.
The primary objective of ITER is the investigation and demonstration of burning plasmas—plasmas in which the energy of the helium nuclei produced by the fusion reactions is enough to maintain the temperature of the plasma, thereby reducing or eliminating the need for external heating. ITER will also test the availability and integration of technologies essential for a fusion reactor (such as superconducting magnets, remote maintenance, and systems to exhaust power from the plasma) and the validity of tritium breeding module concepts that would lead in a future reactor to tritium self-sufficiency.

Thousands of engineers and scientists have contributed to the design of ITER since the idea for an international joint experiment in fusion was first launched in 1985. The ITER Members—China, the European Union, India, Japan, Korea, Russia and the United States—are now engaged in a 35-year collaboration to build and operate the ITER experimental device, and together bring fusion to the point where a demonstration fusion reactor can be designed.

What will ITER do?

The amount of fusion energy a tokamak is capable of producing is a direct result of the number of fusion reactions taking place in its core. Scientists know that the larger the vessel, the larger the volume of the plasma … and therefore the greater the potential for fusion energy.

With ten times the plasma volume of the largest machine operating today, the ITER Tokamak will be a unique experimental tool, capable of longer plasmas and better confinement. The machine has been designed specifically to:

1) Achieve a deuterium-tritium plasma in which the fusion conditions are sustained mostly by internal fusion heating
Fusion research today is at the threshold of exploring a “burning plasma”—one in which the heat from the fusion reaction is confined within the plasma efficiently enough for the self-heating effect to dominate any other form of heating. Scientists are confident that the plasmas in ITER will not only produce much more fusion energy, but will remain stable for longer periods of time.

2) Generate 500 MW of fusion power in its plasma
The world record for fusion power is held by the European tokamak JET. In 1997, JET produced 16 MW of fusion power from a total input heating power of 24 MW (Q=0.67). ITER is designed to yield in its plasma a ten-fold return on power (Q=10), or 500 MW of fusion power from 50 MW of input heating power. ITER will not convert the heating power it produces as electricity, but—as the first of all fusion experiments in history to produce net energy gain across the plasma—it will prepare the way for the machines that can.

3) Contribute to the demonstration of the integrated operation of technologies for a fusion power plant
ITER will bridge the gap between today’s smaller-scale experimental fusion devices and the demonstration fusion power plants of the future. Scientists will be able to study plasmas under conditions similar to those expected in a future power plant and test technologies such as heating, control, diagnostics, cryogenics and remote maintenance.

4) Test tritium breeding
One of the missions for the later stages of ITER operation is to demonstrate the feasibility of producing tritium within the vacuum vessel. The world supply of tritium (used with deuterium to fuel the fusion reaction) is not sufficient to cover the needs of future power plants. ITER will provide a unique opportunity to test mockup in-vessel tritium breeding blankets in a real fusion environment.

5) Demonstrate the safety characteristics of a fusion device
ITER achieved an important landmark in fusion history when, in 2012, the ITER Organization was licensed as a nuclear operator in France based on the rigorous and impartial examination of its safety files. One of the primary goals of ITER operation is to demonstrate the control of the plasma and the fusion reactions with negligible consequences to the environment.

When will experiments begin?

ITER’s First Plasma is scheduled for December 2025*.   First Plasma will be the first time the machine is powered on, and the first act of ITER’s multi-decade operational program.   On a cleared, 42-hectare site in the south of France, building has been underway since 2010. The central Tokamak Building was handed over to the ITER Organization in March 2020 for the start of machine assembly. The first major event of this new phase was the installation of the 1,250-tonne cryostat base in May 2020. In the ITER offices around the world, the exact sequence of assembly events has been carefully orchestrated and coordinated.   The successful integration and assembly of over one million components (ten million parts), built in the ITER Members’ factories around the world and delivered to the ITER site constitutes a tremendous logistics and engineering challenge. The ITER Organization will be carrying out the work supported by a number of assembly contractors (nine contracts in all).   In November 2017, the project passed the halfway mark to First Plasma. (More here.) In July 2020, the project officially launched the machine assembly phase. (More here.) 

About ITER

ITER photo gallery

The energy source of the stars–what a marvelous ambition to harness nuclear fusion in a reactor on Earth. I encourage you to take a look through the photos of the construction of the project. The one below caught my attention:

The complexity of this construction project demands comprehensive planning and rigorous adherence to precise, pre-engineered assembly plans. The sequence of steps in assembling ITER’s million-plus components is crucial, since physical constraints on space and the interdependence of each system means that if something is left out, it may be impossible to add it in later. As complicated as this designed system is, it’s complexity pales in comparison to what we see in living organisms. Imagine building ITER with the additional engineering demand that it not only function to produce fusion energy, but that it contain the machinery to be able to reproduce itself multiple times over!

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At SciTech Daily: SOFIA Finds No Phosphine – a Potential Sign of Life – on Venus

Anashe Bandari writes:

Venus is considered Earth’s twin in many ways. However, recent observations made with the Stratospheric Observatory for Infrared Astronomy (SOFIA) have now made one difference clearer: Unlike Earth, Venus does not have any obvious phosphine.

The spectral data from SOFIA overlain atop this image of Venus from NASA’s Mariner 10 spacecraft is what the researchers observed in their study, showing the intensity of light from Venus at different wavelengths. If a significant amount of phosphine were present in Venus’s atmosphere, there would be dips in the graph at the four locations labeled “PH3,” similar to but less pronounced than those seen on the two ends. Credit: Venus: NASA/JPL-Caltech; Spectra: Cordiner et al.

Phosphine is a gas found in Earth’s atmosphere. In 2020, the announcement of phosphine discovered above Venus’s clouds made headlines because it has strong potential as a biomarker. In other words, the presence of phosphine could be an indicator of life. Although it is common in the atmospheres of gas planets like Jupiter and Saturn, phosphine on Earth is associated with biology. On our planet, it’s formed by decaying organic matter in bogs, swamps, and marshes.

“Phosphine is a relatively simple chemical compound — it’s just a phosphorus atom with three hydrogens — so you would think that would be fairly easy to produce. But on Venus, it’s not obvious how it could be made,” said Martin Cordiner, a researcher in astrochemistry and planetary science at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.

There may be other potential ways to form phosphine on a rocky planet, like through lightning or volcanic activity, but none of these apply if there simply isn’t any phosphine on Venus. And according to SOFIA, there isn’t.

Following the 2020 study, a number of different telescopes conducted follow-up observations to confirm or refute the finding. Cordiner and his team followed suit, using SOFIA in their search.

The recently retired SOFIA was a telescope on an airplane and, over the course of three flights in November 2021, it looked for hints of phosphine in Venus’s sky. Thanks to its operation from Earth’s sky, SOFIA could perform observations not accessible from ground-based observatories. Its high spectral resolution also enabled it to be sensitive to phosphine at high altitudes in Venus’s atmosphere, about 45 to 70 miles (about 75 to 110 kilometers) above the ground — the same region as the original finding — with spatial coverage across Venus’s entire disk.

No sign of phosphine was found by the researchers. According to their results, if there is any phosphine present in Venus’s atmosphere at all, it’s a maximum of about 0.8 parts phosphine per billion parts of everything else, which is much smaller than the initial estimate.

Pointing SOFIA’s telescope at Venus was a challenge in and of itself. The window during which Venus could be observed was short, about half an hour after sunset, and the aircraft needed to be in the right place at the right time. Venus also goes through phases similar to the Moon, making it difficult to center the telescope on the planet. Add in its proximity to the Sun in the sky — which the telescope must avoid — and the situation quickly became tense.

“You don’t want sunlight accidentally coming in and shining on your sensitive telescope instruments,” Cordiner said. “The Sun is the last thing you want in the sky when you’re doing these kinds of sensitive observations.”

Despite the fact the group did not find phosphine after the stressful observations, the study was a success. Along with complementary data from other observatories that vary in the depths they probe within Venus’s atmosphere, the SOFIA results help build the body of evidence against phosphine anywhere in Venus’s atmosphere, from its equator to its poles.

SciTech Daily

Venus – Earth’s twin? Perhaps in size, mass and orbital distance from the Sun, but its runaway greenhouse effect, caused by a mostly CO2 atmosphere at about 100 times the pressure of Earth’s atmosphere, makes it the hottest planet in the solar system. Getting a planet, like Earth, to be habitable to millions of species of life over most of its history is dependent upon much more than a few basic similarities. Something to keep in mind when considering any Earth-like exoplanets that may be found.

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