Structure of Matter Throughout History

Structure of Matter Throughout History Welcome

Modeling the Structure of Matter Throughout History

Rolf Ent and Richard Milner

February 2024

One of the great quests throughout human history has been the effort over thousands of years to understand the structure of matter from the most fundamental constituents. It is driven by human curiosity to understand the physical world in which we have evolved. In addition and equally importantly, advances in understanding the structure of matter have always led to substantial improvements in human quality of life.

Throughout history, models and visualization have been a natural component of understanding. A scientific model seeks to represent measurements, phenomena and physical processes in a logical and objective way. All models are simplified reflections of reality that, despite being approximations, can be really useful. Building, criticizing and improving models is central to science. Visualization is any technique for creating images to communicate a message. Since the cave paintings of our earliest ancestors, visualization has been used effectively to communicate abstract and concrete ideas. History shows ample evidence of development of models to gain insight followed by major conceptual scientific breakthroughs. These breakthroughs then naturally led to a new and more detailed level of models and visualizations.

At present, we are at a crossroads in understanding the fundamental structure of matter. At the deepest levels, we enter a realm that is not deterministic but driven by quantum mechanics, where particles move near the speed of light, are constantly annihilated and created and where all particles strongly interact. There are no fixed structures anymore, which complicates models and visualization and challenges our imagination. Decades of data have been collected on the quark-gluon structure of nucleons and atomic nuclei, but, thus far, we lack the precision and detail needed for the next conceptual breakthrough. Based on the existing data, we have been working with artists to visualize the current understanding of the fundamental quark and gluon structure of protons through animations, which are now widely used. We recently extended such animations to now allow visualization of both the proton-neutron structure and, zooming into the deepest level, the underlying quark-gluon structure of nuclei.

In presenting this work to audiences broadly, we have been struck how our work fits naturally in the long, historic line of models of the structure of matter. Thus, we have worked to describe the modeling of the structure of matter throughout history. We have chosen to present the history in the form of nine posters that can be displayed in an open space where our animations can also be presented simultaneously. These nine posters portray, respectively:

  • The Ancient World – up to 500 AD
  • The Islamic Golden Age – 500 to 1500
  • The Scientific Revolution – 1500 to 1750
  • The Elements – 1750 to 1870
  • The Atom – 1870 to 1925
  • The Nucleus – 1925 to 1955
  • The Proton – 1955 to 2000
  • The Standard Model of Particle Physics – 1960 to 2012
  • 21st Century Models of the Structure of Matter – 2000 to present.

This period saw the rise of civilization. The main emphasis of human development in this era was to develop means to survive. The development of science, technology, engineering and mathematics and related discoveries in this era were driven by the goal to increase the quality of life.

The Roman Empire (from about 30 BC to 476 AD) included much of Europe, North Africa and Western Asia. While the Romans were incredible engineers, they had little interest or impact on science. The Western Roman Empire fell in 476 and in Europe there followed the Dark Ages for most of the next thousand years. Christianity based in Rome dominated in Europe during this time and adopted the Aristotelian view of the physical world. Greek and Roman thinkers left a body of works on philosophy. These works, particularly those by Aristotle, were later translated into Syriac and then Arabic during the Islamic Golden Age. Much later, they were translated from Arabic into Latin and then read by European scholars. The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is understood to have begun during the reign of the Abbasid caliph Harun al-Rashid (786-809) with the inauguration of the House of Wisdom in Baghdad. Here, Islamic scholars and polymaths from various parts of the world with different cultural backgrounds were mandated to gather and translate all of the known world’s classical knowledge into Aramaic and Arabic.

The Scientific Revolution was a series of events that marked the emergence of modern science during the period 1500 to 1750 AD, when developments in mathematics, physics, astronomy, biology and chemistry transformed the views of society about nature. A new view of nature emerged, replacing the Greek view that had dominated science for almost 2,000 years. Science became a recognized discipline, distinct from both philosophy and technology, and came to be regarded as having great benefit for human quality of life. The Scientific Revolution took place in Europe starting towards the end of the Renaissance period, and began with the 1543 Nicholas Copernicus publication On the Revolutions of the Heavenly Spheres that formulated a model of the universe that placed the Sun rather than the Earth at its center.

There were early, ingenious ideas about the internal structure of crystals – mostly based on the close packing of particles. For example, the fact that quartz is often found with close geometric shapes was noted by Pliny the Elder (23–79) in his Natural History: “It is not easy to understand why it has six angles and six faces, especially as the angles do not always have the same appearance. As for the polish of the faces, it is such that no art can equal it.” In the last quarter of the eighteenth century, the French crystallographer R´en´e Just Ha¨uy (1743-1822) proposed a revolutionary model based on the periodic repetition of a submicroscopic polyhedron which is similar to the unit cell of modern structural crystallography. This model preceded the atomic theory of John Dalton (1766-1844) by over thirty years and represented a first modern and general attempt to reasonably represent the atomic structure of the matter. Subsequently, Ha¨uy’s structural model inspired Amedeo Avogadro (1776-1856) and Andr´e Amp`ere (1775-1836) to draw fundamental theoretical consequences from the results published by Jean Louis Gay-Lussac (1778-1850) on the chemical combination of gases.

In the 1860s, the equations that describe electricity and magnetism were written down by the Scottish physicist James Clerk Maxwell. These summarized over a century of investigation in Europe. Most importantly, it was clear from the equations that electromagnetic waves could be generated and propagated. These were first demonstrated experimentally by Heinrich Hertz in the late 1880s. This was the birth of our modern technological society based on wifi, cell phones and GPS.

We have seen that by 1920, the Bohr theory of the neutral atom with Z negatively charged electrons required a small nuclear core of +Z charge. In 1932, the neutron, the neutral partner of the proton, was discovered. Models for the atomic nucleus consisting of protons and neutrons were quickly developed by Werner Heisenberg and others. By 1934, Fermi had bombarded heavier elements with neutrons to induce radioactivity in elements of high atomic number. In 1938, Otto Hahn, Lise Meitner, and Fritz Strassman discovered nuclear fission, or the fractionation of uranium nuclei into light elements, induced by neutron bombardment. The discovery of nuclear fission would lead to the development of nuclear power and the atomic bomb by the end of World War II.

With the availability of new, higher energy particle accelerators in the 1950s, physicists studying the fundamental structure of matter discovered a large number of new particles. These were all bound by the strong force and they were so plentiful that they were labeled the “particle zoo”. In reaction, Wolfgang Pauli is said to have exclaimed “Had I foreseen that, I would have gone into botany.” There was a clear desire to organize the “zoo” in terms of a theory of a few simple constituents.

In parallel with the discovery of the large number of particles – the particle zoo – in the 1950s, physicists had developed theories that the interactions of the fundamental particles are mediated by exchange particles – gauge bosons – acting as force carriers. One example was the pion. In his 1934 article, Hideki Yukawa argued that the nuclear strong force is carried by a particle with a mass approximately 200 times that of an electron. Yukawa received the Nobel Prize in physics for 1949 for predicting the existence of the pion. Another such example is the photon that is the mediating particle of electricity and magnetism.

Many heralds point to a next phase in exploring what lies at the heart of matter, deep inside the quantum world that resides within us and stars. Earlier models of protons and complex atomic nuclei are known to be incomplete. Experimental and theoretical tools are on the horizon to make breakthroughs to the next level of understanding the structure of visible matter.

This period saw the rise of civilization. The main emphasis of human development in this era was to develop means to survive. The development of science, technology, engineering and mathematics and related discoveries in this era were driven by the goal to increase the quality of life.

The Roman Empire (from about 30 BC to 476 AD) included much of Europe, North Africa and Western Asia. While the Romans were incredible engineers, they had little interest or impact on science. The Western Roman Empire fell in 476 and in Europe there followed the Dark Ages for most of the next thousand years. Christianity based in Rome dominated in Europe during this time and adopted the Aristotelian view of the physical world. Greek and Roman thinkers left a body of works on philosophy. These works, particularly those by Aristotle, were later translated into Syriac and then Arabic during the Islamic Golden Age. Much later, they were translated from Arabic into Latin and then read by European scholars. The Islamic Golden Age was a period of cultural, economic, and scientific flourishing in the history of Islam, traditionally dated from the 8th century to the 14th century. This period is understood to have begun during the reign of the Abbasid caliph Harun al-Rashid (786-809) with the inauguration of the House of Wisdom in Baghdad. Here, Islamic scholars and polymaths from various parts of the world with different cultural backgrounds were mandated to gather and translate all of the known world’s classical knowledge into Aramaic and Arabic.

The Scientific Revolution was a series of events that marked the emergence of modern science during the period 1500 to 1750 AD, when developments in mathematics, physics, astronomy, biology and chemistry transformed the views of society about nature. A new view of nature emerged, replacing the Greek view that had dominated science for almost 2,000 years. Science became a recognized discipline, distinct from both philosophy and technology, and came to be regarded as having great benefit for human quality of life. The Scientific Revolution took place in Europe starting towards the end of the Renaissance period, and began with the 1543 Nicholas Copernicus publication On the Revolutions of the Heavenly Spheres that formulated a model of the universe that placed the Sun rather than the Earth at its center.

There were early, ingenious ideas about the internal structure of crystals – mostly based on the close packing of particles. For example, the fact that quartz is often found with close geometric shapes was noted by Pliny the Elder (23–79) in his Natural History: “It is not easy to understand why it has six angles and six faces, especially as the angles do not always have the same appearance. As for the polish of the faces, it is such that no art can equal it.” In the last quarter of the eighteenth century, the French crystallographer R´en´e Just Ha¨uy (1743-1822) proposed a revolutionary model based on the periodic repetition of a submicroscopic polyhedron which is similar to the unit cell of modern structural crystallography. This model preceded the atomic theory of John Dalton (1766-1844) by over thirty years and represented a first modern and general attempt to reasonably represent the atomic structure of the matter. Subsequently, Ha¨uy’s structural model inspired Amedeo Avogadro (1776-1856) and Andr´e Amp`ere (1775-1836) to draw fundamental theoretical consequences from the results published by Jean Louis Gay-Lussac (1778-1850) on the chemical combination of gases.

In the 1860s, the equations that describe electricity and magnetism were written down by the Scottish physicist James Clerk Maxwell. These summarized over a century of investigation in Europe. Most importantly, it was clear from the equations that electromagnetic waves could be generated and propagated. These were first demonstrated experimentally by Heinrich Hertz in the late 1880s. This was the birth of our modern technological society based on wifi, cell phones and GPS.

We have seen that by 1920, the Bohr theory of the neutral atom with Z negatively charged electrons required a small nuclear core of +Z charge. In 1932, the neutron, the neutral partner of the proton, was discovered. Models for the atomic nucleus consisting of protons and neutrons were quickly developed by Werner Heisenberg and others. By 1934, Fermi had bombarded heavier elements with neutrons to induce radioactivity in elements of high atomic number. In 1938, Otto Hahn, Lise Meitner, and Fritz Strassman discovered nuclear fission, or the fractionation of uranium nuclei into light elements, induced by neutron bombardment. The discovery of nuclear fission would lead to the development of nuclear power and the atomic bomb by the end of World War II.

With the availability of new, higher energy particle accelerators in the 1950s, physicists studying the fundamental structure of matter discovered a large number of new particles. These were all bound by the strong force and they were so plentiful that they were labeled the “particle zoo”. In reaction, Wolfgang Pauli is said to have exclaimed “Had I foreseen that, I would have gone into botany.” There was a clear desire to organize the “zoo” in terms of a theory of a few simple constituents.

In parallel with the discovery of the large number of particles – the particle zoo – in the 1950s, physicists had developed theories that the interactions of the fundamental particles are mediated by exchange particles – gauge bosons – acting as force carriers. One example was the pion. In his 1934 article, Hideki Yukawa argued that the nuclear strong force is carried by a particle with a mass approximately 200 times that of an electron. Yukawa received the Nobel Prize in physics for 1949 for predicting the existence of the pion. Another such example is the photon that is the mediating particle of electricity and magnetism.

Many heralds point to a next phase in exploring what lies at the heart of matter, deep inside the quantum world that resides within us and stars. Earlier models of protons and complex atomic nuclei are known to be incomplete. Experimental and theoretical tools are on the horizon to make breakthroughs to the next level of understanding the structure of visible matter.