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Posts Tagged ‘matter

“All is Number… Number rules the universe”*…

 

Threes

 

The universe has cooked up all sorts of bizarre and beautiful forms of matter, from blazing stars to purring cats, out of just three basic ingredients. Electrons and two types of quarks, dubbed “up” and “down,” mix in various ways to produce every atom in existence.

But puzzlingly, this family of matter particles—the up quark, down quark, and electron—is not the only one. Physicists have discovered that they make up the first of three successive “generations” of particles, each heavier than the last. The second- and third-generation particles transform into their lighter counterparts too quickly to form exotic cats, but they otherwise behave identically. It’s as if the laws of nature were composed in triplicate. “We don’t know why,” said Heather Logan, a particle physicist at Carleton University.

In the 1970s, when physicists first worked out the standard model of particle physics—the still reigning set of equations describing the known elementary particles and their interactions—they sought some deep principle that would explain why three generations of each type of matter particle exist. No one cracked the code, and the question was largely set aside. Now, though, the Nobel Prize–winning physicist Steven Weinberg, one of the architects of the standard model, has revived the old puzzle. Weinberg, who is 86 and a professor at the University of Texas, Austin, argued in a recent paper in the journal Physical Review D that an intriguing pattern in the particles’ masses could lead the way forward…

The laws of nature appear to have been composed in triplicate: “Why Do Matter Particles Come in Threes?

* Pythagoras

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As we study structure, we might recall that on this date in 1981, Nature set the world’s record for “Longest Scientific Name” when it published the systematic name for the deoxyribonucleic acid (DNA) of the human mitochondria; it contains 16,569 nucleotide residues and is thus about 207,000 letters long.

220px-Map_of_the_human_mitochondrial_genome.svg

The 16,569 bp long human mitochondrial genome with the protein-coding, ribosomal RNA, and transfer RNA genes

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Written by LW

April 9, 2020 at 1:01 am

“Matter is energy waiting to happen”*…

 

matter abstractions-a-442

 

Chad Mirkin didn’t set out to discover a new property in matter. But when you’re inventing an alternative to atom-based chemistry, something strange is bound to happen…

While studying materials made from DNA-coated nanoparticles, researchers found a new form of matter– lattices in which smaller particles roam like electrons in metallic bonds: “Strange Metal-like Bonds Discovered in Customized Crystals.”

* Bill Bryson, A Short History of Nearly Everything

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As we muse on matter, we might send irradiated birthday greetings to Irène Joliot-Curie; she was born on this date in 1897.  The daughter of Marie Curie and Pierre Curie and the wife of Frédéric Joliot-Curie, she shared a Nobel Prize with her husband for their joint discovery of artificial radioactivity (making the Curies the family with the most Nobel laureates to date).  Both children of the Joliot-Curies, Hélène and Pierre, are also esteemed scientists.

Like her mother, Irène died of leukemia, likely resulting from radiation exposure during her research.

220px-Irène_Joliot-Curie_Harcourt source

 

Written by LW

September 12, 2019 at 1:01 am

“Energy is liberated matter, matter is energy waiting to happen”*…

 

We’ve certainly come a long way since the ancient Greek atomists speculated about the nature of material substance, 2,500 years ago. But for much of this time we’ve held to the conviction that matter is a fundamental part of our physical universe. We’ve been convinced that it is matter that has energy. And, although matter may be reducible to microscopic constituents, for a long time we believed that these would still be recognizable as matter—they would still possess the primary quality of mass.

Modern physics teaches us something rather different, and deeply counter-intuitive. As we worked our way ever inward—matter into atoms, atoms into sub-atomic particles, sub-atomic particles into quantum fields and forces—we lost sight of matter completely. Matter lost its tangibility. It lost its primacy as mass became a secondary quality, the result of interactions between intangible quantum fields. What we recognize as mass is a behavior of these quantum fields; it is not a property that belongs or is necessarily intrinsic to them.

Despite the fact that our physical world is filled with hard and heavy things, it is instead the energy of quantum fields that reigns supreme. Mass becomes simply a physical manifestation of that energy, rather than the other way around…

Modern physics has taught us that mass is not an intrinsic property: “Physics Has Demoted Mass.”

* Bill Bryson, A Short History of Nearly Everything

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As we watch all that is solid melt into air, we might spare a jaundiced thought for Trofim Denisovich Lysenko; he died on this date in 1976.  A Soviet biologist and agronomist, he believed the Mendelian theory of heredity to be wrong, and developed his own, allowing for “soft inheritance”– the heretability of learned behavior. (He believed that in one generation of a hybridized crop, the desired individual could be selected and mated again and continue to produce the same desired product, without worrying about separation/segregation in future breeds.–he assumed that after a lifetime of developing (acquiring) the best set of traits to survive, those must be passed down to the next generation.)

In many way Lysenko’s theories recall Lamarck’s “organic evolution” and its concept of “soft evolution” (the passage of learned traits), though Lysenko denied any connection. He followed I. V. Michurin’s fanciful idea that plants could be forced to adapt to any environmental conditions, for example converting summer wheat to winter wheat by storing the seeds in ice.  With Stalin’s support for two decades, he actively obstructed the course of Soviet biology and caused the imprisonment and death of many of the country’s eminent biologists who disagreed with him.

Interestingly, some current research suggests that heritable learning– or a semblance of it– may in fact be happening, by virtue of epigenetics… though nothing vaguely resembling Lysenko’s theory.

 source

 

Written by LW

November 20, 2017 at 1:01 am

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