All matter originates and exists only by virtue of a force.
Max Planck
There is a persistent view of the material world in which every object is composed of separate particles, called atoms, which are themselves composed of still more separate particles, called subatomic particles. Those particles which cannot be divided into smaller parts are called elementary particles, or quanta, making them the ultimate substance of the entire universe. This picture of things gives us convenient and useable model of what the physical world seems to be, such as in the Standard Model of particle physics, but the more we come to understand just what quanta are, the more we begin to see how limited this classical view is. First of all, matter and energy are both composed of quanta and today are considered to be merely two different aspects of the same thing, which could be called, in the tradition of spacetime, matterenergy. Even the distinction between a particle and a wave becomes fuzzy in the quantum realm. Quanta can literally act like either a particle or a wave, which has led to them being referred to as wavicles.
In the Standard Model, certain quanta are treated as purveyors of the forces of Nature, while in pure field theory the forces fields are thought of as primary and quanta are merely manifestation of the underlying force fields. Either way, only through our limited experience and measurement of quanta is physical reality realized, and these scattered enigmatic pieces seem to hint that a deeper reality exists. As convenient as it is to think of the Universe as being composed of separate particles scattered around in empty space, this classical view of things simply does not provide a complete picture of the way things are.
In quantum field theory, quanta are treated as point particles, singularities, and the atom is best described as a dynamic system of quantum processes, a resonating pattern of interacting force fields. The closer we look into the atom, the more intense these processes become and the more any notion of solidity seems to 'zoom away' to a deeper level. In a very real sense, the realm of the quantum becomes just as far away as the realm of the quasar.
Mathematically, today's model of the atom contains multidimensional gauge fields and vector bundles, a sort of 'emptiness' full of ethereal symmetries, and the experience of the solidity of matter arises from the mutual repulsion of negatively charged electron fields. Solidity is a surface illusion. Even the electron itself is not solid. Like all quantum particles, it must be treated mathematically as a singularity, and without any way to ever know its precise position and momentum at the same time, it is entirely impossible to pin it down as an "object in spacetime". It is important to realize that this ethereal nature of matter is not merely a limitation of the mathematics of physical theory, but is in fact a most fundamental characteristic of physical reality.
Even the classical notion of empty space has been replaced with the quantum vacuum, a quantum foam of creation and destruction at the tiniest scale. Quantum theory suggests that at any point in the vacuum of space there is a certain probability that a real particle, a quantum, will simply pop into existence out of nothing, along with what is called its virtual particle counterpart, only to immediately annihilate each other again back into nothingness. In fact, this process is considered to actually be happening all the time, at every point in the vacuum of space.
In 1974, Stephen Hawking combined quantum theory and Relativity, particle physics and cosmology, by conceptually placing a black hole in the quantum vacuum. The result was the startling realization that, through a very strange process, black holes actually emit energy, and the smaller they are, the hotter they shine. In some cases, they even become indistinguishable from white holes, and in all cases, they eventually evaporate away to nothing.
Unified Field Physics
The theoretical core of modern physics deals with Unified Field Theories which attempt to express the four fundamental forces of the Universe as aspects of a single Universal Superforce. With subtle differences, they all share the same key principles of Relativity and quantum physics. Which model is 'most correct' is probably not as important as the realization of universal oneness to which they all point.
The mathematics used to describe quantum physics presents a number of strange implications that defy normal objective logic. Besides the wave-particle duality, the principle of complementarity shows itself in the fact that certain physical properties of quanta, such as position and momentum, cannot be known at the same time -- if we measure one property, the other becomes indeterminable. This indeterminism is known as Heisenberg’s Uncertainty Principle and the wave-particle duality is directly related. Also, an interpretation of the quantum wavefunction suggests that, before a measurement is made, all possible outcomes of that measurement must be thought of as actually existing, in some way, as a set of superimposed realities.
Perhaps most bizarre, it seems that the quanta which define matter and energy all across the Universe are somehow connected as if they had no spatial separation. This feature of quantum theory is known as nonlocality, referring to nonlocal (spacetime-independent) connections. Today it is generally called quantum entanglement. Clearly, quantum mechanics cannot be interpreted in the terms of classical Newtonian mechanics.
Nevertheless, the mathematics works extremely well in describing what is observed in the subatomic realm. In the early days of quantum theory, it was generally believed that the strange implications arose from the use of matrix mechanics (or wave mechanics), for example, and there was hope that a more rational interpretation would someday become clear. Einstein was disturbed by the way the quantum theory challenged the logical objective view of the Universe. This led to his famous discussions with Niels Bohr.
Experiments in recent decades, however, designed to test what is called Bell's Theorem, have shown that nonlocality, or quantum entanglement, is indeed a physical characteristic of reality. Today, the phenomenon is even routinely used in electronic devices. Obviously, a fundamental shift in our understanding of physical reality has been realized and the need for a real interpretation of quantum physics has become more apparent.
Today's mathematical models of the quantum realm have implications that reach back to the earliest stages of the Universe, yet they will never be objectively verified in the way classical Newtonian mechanics has been. It is simply not practical to do so. The scientist of today must rely on emerging patterns and hints experienced at the relatively macroscopic level of the particle accelerators, and finally on the aesthetic beauty of the mathematics itself to help establish which direction to take toward truth. This brings to mind the famous words of John Keats: "Beauty is Truth, Truth Beauty."
Strangely enough, aesthetics and intuition are more than ever guiding the intellectual community in their quest for understanding the most fundamental principles of the Universe. It is at least satisfying to know that these "new" visions of reality are fundamentally simple and intuitively beautiful. It would appear that we could say, Beauty is indeed Truth, and physics has become metaphysics.
"It is quite clear that beauty does depend on one's culture and upbringing for certain kinds of beauty, pictures, literature, poetry and so on... But mathematical beauty is of a rather different kind. I should say perhaps it is of a completely different kind and transcends these personal factors. It is the same in all countries and at all periods of time." -- Paul Dirac
That which cannot be seen nor seized,
which has no eyes nor ears, no hands nor feet;
the eternal, the omnipresent, subtle and infinitesimal;
that it is which the wise regard the source of all beings.
Mundaka Upanishad
