5 Mar 2006

How does modern physics view The Universe?


“The least understood aspect of the universe is its being understandable,” said Einstein. These words attempt to pierce the veil of habit that develops in our minds from not looking into the reason for things. The perfection of the order operative in the universe is of such a degree that it prevents us from being aware of it. In the same way, we only become aware of the faultless operation of the watches we’ve worn on our wrists for years when they stop working.

In the world-view developed upon the foundation of Newton’s laws of motion, the universe was likened to a flawlessly operating watch. Events were tied to one another in a cause-effect relationship and our knowing the laws of this relationship allowed us to predict events with great accuracy. It was possible to determine with mathematical exactness a wide range of phenomena, from the times of eclipses of sun and moon to the amount of fuel and the speed needed to put an object into orbit around the earth. The success of these ‘natural laws’ led many people to believe that they completely expressed and ‘ruled’ the whole order of the universe.

Because God creates and sustains all things and events from behind the veil of universal general laws, because certain events (causes) are followed reliably by similar events (effects) each time they (the causes) occur, it begins to be supposed that the causes are responsible for or ‘create’ the effects. This is, of course, a gross error, as no number of causes suffices to create even a little effect; for every event, even the tiniest, the whole universe must be presupposed first, including the laws operative within it. Moment by moment, all things and all events are created and sustained by God, Who wills from an infinite range of alternative possibilities a particular actuality.

The clockwork model of the universe derived from Newtonian or classical physics is not a complete account of the phenomena which we observe in the universe. Already in the late 19th century, scientists had been bewildered by the lines that turned up in the light spectra emitted by heated gases: the steady, stable, even distribution the clockwork model predicted did not happen. Also, there were problems explaining the behavior of light: sometimes it made more sense as a beam of particles, sometimes as a wave.

Today our understanding of the universe is very far from the ‘clockwork’ model. The shift in understanding occurred in the first quarter of the 20th century, beginning in 1900 with the publication of Max Planck’s work on radiation. The problem Planck worked on for six years was that the actually measured radiation from hot bodies did not conform to the values predicted by the classical theory. He put forward the suggestion that bodies radiating energy did so, not evenly and continuously, but unevenly and discontinuously in tiny packets or ‘quanta’. So startling was this suggestion that, despite confirmation by experiment, Planck himself thought of his theory as solving the problem of radiation by a sort of trick.

But then, in 1905, Albert Einstein published an article using the notion of packets of energy of definite sizes to explain how electrons are ejected from metal when light (radiation) falls on it. Whereas classical theory had predicted that the voltage (measure of the energy of the electrons ejected) would be proportional to the intensity of the light (radiation), Einstein showed that it was proportional instead to the frequency of the radiation. The conformity of this explanation with experimentally observed results gained Einstein the Nobel Prize. (Einstein didn’t receive the prize for his famous theory of relativity.) The significance of these findings and theories was not fully appreciated at the time.

A few years later in 1910, Ernest Rutherford did a ground-breaking experiment. He bombarded a thin layer made up of gold atoms with high energy particles and showed that the atom contained an extremely small positively-charged nucleus with negatively-charged electrons moving around it. Following the classical physics model, these electrons should have been small particles orbiting the nucleus in the same way as the planets orbit the sun, steadily losing energy until they fell on to the nucleus ñ in other words, the atom should have been unstable. Again it was a rejection of the classical model, three years later, by Niels Bohr, that helped solve the problem. Bohr argued that the electrons must move in fixed orbits until deflected by the absorption or emission of a unit of energy.

Atoms emit radiation after various external signals and only at specific wave lengths. As Einstein said, every different color of light is composed of energy packets inversely proportional to its wavelength (frequency). Because the Planck constant (h) is very small, the energy of these packets is also very, very small. For example, a normal light bulb emits 1020 light packets (photons) a second. Each of these photons is created when an activated atom or molecule passes to its normal or ‘basic state.’ Thus light, which allows us to see and which is a basic building block of life, develops as a result of the motions (in wave form) of electrons. The concepts of classical physics could successfully explain many of the events of daily life, but it couldn’t explain events on the subatomic level.

During those years (1910-1925) physics fell into a state of confusion because of the many measurements that conflicted with general theory and could not be explained by it. This situation was to lead W. Pauli (later to discover the principle fundamental to the understanding of the structure and characteristics of elements) to say he would rather have been a singer or gambler than a physicist. Actually in order to explain the observations being made, the whole way in which physical events had been understood required fundamental revision by wholly new methods. This was achieved by Werner Heisenberg, a 24 year-old physicist described by his teachers as a person who dealt with the essence of a subject rather than getting bogged down in detail, a person with powerful concentration and ambition. Perhaps the success of this young mind can be explained by the critical perspective he developed through reading the works of great men such as Kant and Plato, which was later supported with sound knowledge he got from great physicists. Heisenberg, who relaxed from work by climbing rocks and reading poetry, said: “It was around three in the morning when the calculations were completed and the solution to the problem appeared in front of me. First I experienced a great shock. I was so excited I didn’t even think about sleeping. I left the house and, sitting on a rock, I waited for the sunrise.”

Like the other scientists who established quantum physics, Heisenberg was a philosopher-physicist. The philosophy he accepted and advocated that allowed him to interpret atomic events is as follows: “Even though it is successful with classical physics, the language we use to explain physical events in the atom or its surroundings is insufficient. For this reason, after making a specific measurement in a quantum system (for example, an atom), using that knowledge we can get a theory that will tell us what kind of results we can find in the next measurement. But it’s not possible to say anything about what takes place between the two measurements.”

What pushed Heisenberg to make such a statement was that the mathematical tools he used to develop a theory that could explain the observed discontinuity of energy in light and atoms were abstract concepts that had not been used before. In classical physics the numbers we know were used to give value to matter’s position, speed, size, etc. In Heisenberg’s quantum mechanics, these sizes were expressed with infinite dimensional n x n matrices which enabled physicists to calculate the properties attributed to electrons (energy, position, momentum, angular momentum) in an approximate way. Because these abstract mathematical expressions didn’t have an equivalent in everyday spoken language, it wasn’t possible to approach them with a classical understanding. It was observed that in order to measure the position of an electron, the experimenter necessarily altered its velocity. This problem was formally expressed in 1927 in Heisenberg’s famous Uncertainty Principle.

Independently of Heisenberg, Erwin Schrodinger made another significant breakthrough in mathematical description of electrons. Inspired by the hypothesis put forward two years earlier by De Broglie about the wave properties of matter particles, Schrodinger developed a ‘wave mechanics’ by which the movement of particles could be calculated. But the fundamental question remained as to what these strange and original ‘waves of matter particles’ or ‘waves accompanying matter particles’ were.

The mathematical formulations devised by Heisenberg and Schrodinger are complementary in the sense that physicists use whichever best resolves the particular calculations they are trying to make. There is no formally distinct space between the scientists and the phenomena they are seeking to understand and manipulate: their means of observation and manipulation (the mathematics) in some sense ‘posit’, put in place, the very phenomena whose place (among other properties) they are trying to determine. Alongside the notion of an infinite array of rows and points, as invented by Heisenberg, to plot the position or motion of a sub-atomic particle, physicists and philosophers of physics have begun to speak of arrays of events or ‘stories’ to try to explain, in something resembling ordinary language, the ideas they are handling. This cannot be described as a world-view in the way that the Newtonian physics confirmed and sustained a world-view, but it is nevertheless a clear and distinct disposition which, instead of excluding God as the Force Who wound up the clockwork and then retired from His creation, admits the incompleteness and uncertainty of human knowledge as a structural element of reality ñ in other words, the uncertainty is not a function of our present ignorance (to be relieved by future knowledge), but an actual constituent of the way reality is.

Quantum physics, at least figuratively and metaphorically, has became a vehicle for the interpretation of such concepts as matter, beyond-matter, energy, existence and non-existence in a way nearer to Divine sources; and led to many physicists settling accounts with their conscience and turning towards God Who is understood to be simultaneously transcendent and immanent, there and here.

1 comment:

ajzhyder said...

https://topicsfromquran.wordpress.com/2018/05/19/creation-of-skies-and-the-earth/


The link to above post reviews Ayas of Quran related to Creation of Cosmos