Aug 25, 2023 09:03 PM
(This post was last modified: Aug 25, 2023 09:05 PM by C C.)
https://aeon.co/essays/why-the-empty-ato...tum-theory
EXCERPTS (Mario Barbatti): . . . Google ‘atoms empty space’, and you will find tens of essays, blog posts and YouTube videos concluding that atoms are 99.9 per cent empty space. To be fair, you will also find a reasonable share of articles debunking the idea.
Misconceptions feeding the idea of the empty atom can be dismantled by carefully interpreting quantum theory, which describes the physics of molecules, atoms and subatomic particles. According to quantum theory, the building blocks of matter – like electrons, nuclei and the molecules they form – can be portrayed either as waves or particles. Leave them to evolve by themselves without human interference, and they act like delocalised waves in the shape of continuous clouds.
On the other hand, when we attempt to observe these systems, they appear to be localised particles, something like bullets in the classical realm. But accepting the quantum predictions that nuclei and electrons fill space as continuous clouds has a daring conceptual price: it implies that these particles do not vibrate, spin or orbit. They inhabit a motionless microcosmos where time only occasionally plays a role.
Most problems surrounding the description of the submolecular world come from frustrated attempts to reconcile conflicting pictures of waves and particles, leaving us with inconsistent chimeras such as particle-like nuclei surrounded by wave-like electrons. This image doesn’t capture quantum theory’s predictions. To compensate, our conceptual reconstruction of matter at the submolecular level should consistently describe how nuclei and electrons behave when not observed – like the proverbial sound of a tree falling in the forest without anyone around.
Here’s a primer on how to think of the fundamental components of matter: a molecule is a stable collection of nuclei and electrons. If the collection contains a single nucleus, it is called an atom. Electrons are elementary particles with no internal structure and a negative electric charge. On the other hand, each nucleus is a combined system composed of several protons and a roughly equal number of neutrons. Each proton and neutron is 1,836 times more massive than an electron. The proton has a positive charge of the same magnitude as an electron’s negative charge, while neutrons, as their name hints, have no electric charge. Usually, but not necessarily, the total number of protons in a molecule equals the number of electrons, making molecules electrically neutral.
The interior of the protons and neutrons is likely the most complex place in the Universe. I like to consider each of them a hot soup of three permanent elementary particles known as quarks boiling along inside, with an uncountable number of virtual quarks popping into existence and disappearing almost immediately. Other elementary particles called gluons hold the soup within a pot of 0.9 femtometres radius. (A femtometre, abbreviated fm, is a convenient scale that measures systems tens of thousands of times smaller than an atom. Corresponding to 10‑15 m, we must juxtapose 1 trillion femtometres to make one millimetre.)
[...] If atoms and molecules remained a collection of point-like particles, they would be mostly empty space. But at their size scale, they must be described by quantum theory. And this theory predicts that the wave-like picture predominates until a measurement disturbs it. Instead of localised bullets in empty space, matter delocalises into continuous quantum clouds.
Matter is fundamentally quantum. Molecules cannot be assembled under the rules of classical physics. The classical electrical interactions between nuclei and electrons are insufficient to build a stable molecule. Due to the electric attraction of charges of opposite signs, the negatively charged electrons would quickly spiral toward the positively charged nuclei and glue to them. The resulting combined particles with no net charge would fly apart, preventing any molecule from forming.
Two quantum properties avoid this bleak fate... (MORE - missing details)
EXCERPTS (Mario Barbatti): . . . Google ‘atoms empty space’, and you will find tens of essays, blog posts and YouTube videos concluding that atoms are 99.9 per cent empty space. To be fair, you will also find a reasonable share of articles debunking the idea.
Misconceptions feeding the idea of the empty atom can be dismantled by carefully interpreting quantum theory, which describes the physics of molecules, atoms and subatomic particles. According to quantum theory, the building blocks of matter – like electrons, nuclei and the molecules they form – can be portrayed either as waves or particles. Leave them to evolve by themselves without human interference, and they act like delocalised waves in the shape of continuous clouds.
On the other hand, when we attempt to observe these systems, they appear to be localised particles, something like bullets in the classical realm. But accepting the quantum predictions that nuclei and electrons fill space as continuous clouds has a daring conceptual price: it implies that these particles do not vibrate, spin or orbit. They inhabit a motionless microcosmos where time only occasionally plays a role.
Most problems surrounding the description of the submolecular world come from frustrated attempts to reconcile conflicting pictures of waves and particles, leaving us with inconsistent chimeras such as particle-like nuclei surrounded by wave-like electrons. This image doesn’t capture quantum theory’s predictions. To compensate, our conceptual reconstruction of matter at the submolecular level should consistently describe how nuclei and electrons behave when not observed – like the proverbial sound of a tree falling in the forest without anyone around.
Here’s a primer on how to think of the fundamental components of matter: a molecule is a stable collection of nuclei and electrons. If the collection contains a single nucleus, it is called an atom. Electrons are elementary particles with no internal structure and a negative electric charge. On the other hand, each nucleus is a combined system composed of several protons and a roughly equal number of neutrons. Each proton and neutron is 1,836 times more massive than an electron. The proton has a positive charge of the same magnitude as an electron’s negative charge, while neutrons, as their name hints, have no electric charge. Usually, but not necessarily, the total number of protons in a molecule equals the number of electrons, making molecules electrically neutral.
The interior of the protons and neutrons is likely the most complex place in the Universe. I like to consider each of them a hot soup of three permanent elementary particles known as quarks boiling along inside, with an uncountable number of virtual quarks popping into existence and disappearing almost immediately. Other elementary particles called gluons hold the soup within a pot of 0.9 femtometres radius. (A femtometre, abbreviated fm, is a convenient scale that measures systems tens of thousands of times smaller than an atom. Corresponding to 10‑15 m, we must juxtapose 1 trillion femtometres to make one millimetre.)
[...] If atoms and molecules remained a collection of point-like particles, they would be mostly empty space. But at their size scale, they must be described by quantum theory. And this theory predicts that the wave-like picture predominates until a measurement disturbs it. Instead of localised bullets in empty space, matter delocalises into continuous quantum clouds.
Matter is fundamentally quantum. Molecules cannot be assembled under the rules of classical physics. The classical electrical interactions between nuclei and electrons are insufficient to build a stable molecule. Due to the electric attraction of charges of opposite signs, the negatively charged electrons would quickly spiral toward the positively charged nuclei and glue to them. The resulting combined particles with no net charge would fly apart, preventing any molecule from forming.
Two quantum properties avoid this bleak fate... (MORE - missing details)
