“Classical physics explains the world quite well; it’s just the details it can’t handle. Quantum physics handles the “details” perfectly; it’s just the world it can’t explain. You can see why Einstein was troubled.”
I’ve mentioned the book that I’ve been reading entitled “Quantum Enigma.” So far, I’ve only read background information on classical physics- the first seven chapters, but it’s valuable information in understanding the quantum enigma. That is why I will attempt to summarize what I am reading in order to understand things more clearly and to hopefully provide insight to others simultaneously.
Back in the day, classical physics was referred to as “Natural Philosophy.” It all sort of started with Aristotle- who claimed “everything that happens is essentially the motion of matter,” that “an object sought rest with respect to the cosmic center, which clearly was the Earth.” Since objects desired to be at the cosmic center, a heavy object, with greater desire, would fall faster than a light object. On the other hand, celestial objects moved in the most perfect of figures- the circle, and fell toward the Earth, as the cosmic center. This became the official dogma of the Church in the late Middle Ages, thanks to Thomas Aquinas. Aquinas furthered this theory in believing that– because Earth was the cosmic center, where things fell- it was also the realm of morally “fallen” man. Furthermore, “Heaven, where things moved in perfect circles, was the realm of God and His angels.” The center of the Earth was Hell- the lowest point in the universe. We are now well aware that Earth is not the center of the universe.
Galileo was one to refute Aristotle’s theory. He spent the last years of his life under house arrest because of his belief that the earth moved, and the church did not appreciate that independent thought. Although he was shown the torture chambers he still adhered to his claim of a sun-orbiting Earth, and was found guilty of heresy. It wasn’t until Sir Isaac Newton came along- the year Galileo died, when someone understood Galileo. Eventually Newton came up with the laws of nature we are taught today. Interestingly, while Newton was a very respected man in the West for his intelligence, “Paradoxically, Newton was also a mystic, immersing himself in supernatural alchemy and the interpretation of Biblical prophecies.”
What I find particularly intriguing about the background provided is that there were so many criticisms against these revolutionary scientists theories at first. People refused to believe in the new discoveries being made in this time because it often contradicted their perfect worldview they already had. There was nothing left to be discovered in their eyes.
Many respected physicists in this time derided their- (Newton, Faraday, Planck, Einstein, etc) theories and basically called them idiots. The scientists we now boast to be genius’ suffered harsh criticism which contributed to their reluctance on publishing more theories. They were mocked, laughed at, and simply not taken serious. It wasn’t until many years later that people began to give the slightest consideration to their revelations. Some of them died before their ideas were recognized and widely accepted.
Michael Faraday is one example of facing such criticism. After the acceptance of Benjamin Franklin’s knowledge of electric charges, Faraday had a hard time grasping the concept. He wondered how a body could cause a force on another through empty space. This is when he suggested that an electric charge creates and electric “field” in the space around itself and this physical field is the force that is exerted on other charges. Instead of accepting his field concept, it was instead ridiculed as ‘Faraday’s mental crutch’ because his thinking was believed to be too abstract. “Today, the fundamental theories of physics are all formulated in terms of field’s. Faraday’s “mental crutch” is a pillar upon which all of physics now rests.”
While their discoveries are very important to our understanding of the universe and exactly why we are here/where we came from, they are still just assumptions and approximations that conveniently explain the functioning of the universe. However, the fact is that these scientists who laid down the foundation to our carefully paved road of education learned this in a primitive time. They used lanterns to determine the speed of light, an apple falling from a tree to explain gravity, etc. They simply observed, and although remarkably accurate, there is still more to be discovered. That is why it is important that we have a better understanding of Quantum physics and that we take this knowledge in with an open-mind, as it is a very difficult pill to swallow.
The book explains quantum theory as the skeleton in physics closet. Although the theory is successful- as in, “not a single one of it’s theory’s predictions has ever been shown wrong,” many people have a hard time accepting- or even understanding, quantum theory. This is because most people will agree that a single object can’t be in two far-apart places at once, and the actions we make here do not instantly affect what happens someplace far away. Also, we share a common belief that there is a real world “out there” whether or not we are looking at it.
Quantum theory came about as a way to describe the behavior of atoms, or very small particles- the “details.” The authors of this book mention our “Darwinian worldview,” and how such a view can corrupt our ability to take in new information that seems illogical because it contradicts common-sense, and much of our foundation of science- or basically everything we know. Darwin’s theory of evolution seems somewhat logical, and therefore is widely accepted. On the other hand, when trying to summarize quantum theory in a few sentences, it only sounds mystical and is often dismissed. Here is the summary Rosenblum and Kuttner came up up with:
“We risk a rough summary anyway. Quantum theory tells that the observation of an object can instantaneously influence the behavior of another greatly distant object- even if no physical force connects the two. These are the influences Einstein rejected as “spooky actions– (now called ‘entanglement’),” but they have now been demonstrated to exist. Quantum theory also tells us that an object can be in two places at the same time. Its existence at the particular place where it happens to be found becomes an actuality only upon its observation.”
Then they proceed to talk about determinism, idealism, and solipsism. I found their statements on determinism particularly interesting so I will share-
Determinism: think of the classic example in physics using billiard balls. If the position and velocity are known, with Newton’s physics you can predict the position and velocity after they collide arbitrarily far into the future. When thinking about this in a divine sense, think about the “all-seeing eye’ that knew the position and velocity of each atom in the universe at a given moment- the entire universe would be apparent. The future of such a Newtonian universe is, in principle, determined.” In light of this thought, think about whether or not your seemingly free choices are actually predetermined. Well, Max Planck rules this issue out when he has electrons behaving randomly.
We now have “Maxwell’s equations” which validated the existence of electric and magnetic fields: electromagnetic waves. After Maxwell died it was demonstrated that light could be thought of as an electromagnetic wave. Finally, we know that the frequency of motion of the charge is the frequency of the wave produced.. (higher frequencies= ultraviolet, x-rays, lower f’s= infrared, radio waves..). Planck first brought up quantum mechanics through his “Quantum Jumping” theory- suggesting energy loss/change in energy of a charged particle was the result of quantum jumps, which can’t be seen as they are very small. However, this theory violated laws of electromagnetism and Newton’s universal equation of motion. Therefore, the theory resulted in much criticism and Planck discontinued his work on this theory.
Then one day, along came Einstein- whose younger years were quite the struggle that I was not completely aware of. His parents worried about mental retardation when he was young because he was slow to start talking. Then, he struggled to finish school because he simply lacked interest. When asked to suggest a profession Albert might follow, his Headmaster confidently stated: “It doesn’t matter; he’ll never make a success of anything.”
After much searching for work, Einstein finally got a job in Swiss patent office writing summaries of patent applications to decide whether an idea warranted a patent. This job was suitable for Einstein as he was able to work on his own projects behind closed doors. One day, while experimenting with atoms, he noticed a mathematical similarity between the equation for the motion of atoms and Planck’s radiation law. This led him to wonder if light was similar to atoms not only mathematically, but physically as well? In other words, “like matter, might light come in compact lumps? Atoms of light as well as atoms of matter?” Thus, Einstein came up with photons, where he believed that light is a stream of compact lumps.
Each photon would have an energy equal to Planck’s constant- the number Maxwell Planck struggled to find when coming up with his equations. In order to corroborate his speculation, Einstein looked to photoelectric effect. Basically, Einsteins photon hypothesis supported Planck’s theory, in the fact that “the ejection of electrons by light has to do with radiation emitted by hot bodies- it was discovered that the quantum was universal.” When Einstein was awarded the Nobel prize in 1922 for the photoelectric effect, a statement was made that he was “Almost the only one to take the light-quantum seriously…… In a single year,1905, Einstein discovered the quantum nature of light, firmly established the atomic nature of matter, and formulated the theory of relativity.” If only we could hear what his headmaster had to say now..
The reaction to Einstein’s photons, however, was rejection.. surprise! This is because Einstein’s theory was contradicted with Young’s two-slit experiment where light could be thought of as a spread-out wave. In the two slit experiment, a monochromatic light is shined through two slits. Once the light passes through the slits and hits the screen ahead, a pattern of bright and dark fringes appear which is known as the interference pattern. Particles could not do that. The dark spots indicate that wave crests from one slit arrive with the wave troughs from the other and the waves cancel (destructive interference). The bright spots indicated that the waves combine, resulting in constructive interference. Therefore, the interference pattern from this experiment indicates that lights is a spread out wave. But with the photoelectric experiment, light could not be a spread out wave, it has to be a stream of tiny compact particles. We have a paradox indeed! And because this paradox is yet to be explained, this is the quantum enigma.
Physicists had accepted that electrons, and other matter as well as light could be demonstrated as either compact lumps or widely spread-out waves.
Recognition of the wave-particle paradox came with Schrödinger’s equation. Eventually, Schrödinger came up with an initial interpretation of “waviness”- the absolute square of a wavefunction. His initial interpretation was that an object’s waviness was the smeared out object itself. The reason this initial interpretation is wrong is because “although an object’s waviness may be spread over a wide region, when one looks at a particular spot, one immediately finds either a whole object there, or no object in that spot.” In order for a “physical object to be smeared over the extent of it’s waviness, it’s remote parts would have to instantaneously coalesce to the place where the object was found.” Thus, “physical mater would have to move at speeds greater than light- that’s impossible.”
The accepted interpretation of waviness- one that is hard to believe.. the quantum enigma: “The waviness in a region is the probability of finding the object in a particular place.” NOT the object being in a particular place. Somehow, your looking caused it to be in a particular place (think of the photoelectric effect and the two-slit experiment).
“Waviness is probability.” The authors give this example to try and explain this concept:
Think of a carni demonstrating the game where he places a pea under a shell and you watch his hands shuffle the shells around and you determine which shell the pea is under. After rapid shuffling, your eyes lose track of the shell that holds the pea. There is equal probability for the pea to be in either of the two places. It’s 50/50. 50 + 50 = 100. Therefore, the sum of probabilities is certain that the pea is surely under one of the two shells. Once the carni lifts the shell on the right, suppose you see the pea. Instantaneously, it becomes certain that the pea was under the right-hand shell. The probability collapses to zero for the left shell and 100 for the right shell. Even if the shell on the left had moved across town before the shell on the right was lifted, the collapse of probability would still be instantaneous. Great distance does not affect how fast probability can change.
This is where things start to get tricky, as there is a crucial difference between classical probability, and quantum probability. Classical probability is subjective. It is a statement of someone’s knowledge. Not knowing which shell the pea was under, the probability is 1/2, but the probability may be different for the carni, who is in control. Therefore, someone’s knowledge of the situation is not the whole story. On the other hand, quantum probability is objective. It is the same for everyone. The wavefunction is the whole story. For example, “if someone looked in a particular spot and happened to see the atom there, that look ‘collapsed’ the spread out waviness of that atom to be wholly in that particular spot. The atom would be in that spot for everyone (if he looked and found the atom not there, it would not be there for everyone)… someone looking in a different spot would surely not find the atom at that particular spot. But, the waviness of that atom existed at that different spot immediately before the first observer collapsed it.”
A theory in classical physics predicts what you will see in an experiment. For a tossed ball, classical physics tells the position of the ball at any time, even if it’s not being observed. The ball is assumed to actually exist at some particular place.
Quantum mechanics is intrinsically probabilistic. Probability is all there is. Quantum mechanics does not tell the probability of where an object is but rather, if you look, you will observe the object at a particular place. The position of the object is not independent of it’s observation, the observed cannot be separated from the observer.
In conclusion, if you’re accepting of this quantum theory, you can conclude that waviness is the probability of what you will observe- but it depends how you look. You can look directly at the object and demonstrate it to be a compact thing in a particular place (photoelectric effect). Or you can do an interference experiment and demonstrate it had been a widely spread out thing (two-slit experiment).
On the other hand, if you don’t quite understand you may think the theory only gives waviness. This is what disturbed Einstein, Schrödinger, and many experts today- the apparent denial of physical reality that quantum theory suggests. “According to this theory, there was not an actual atom in a particular place before we looked, or “collapsed the wavefunction,” and found an atom there. But there are actual atoms, and actual things made of atoms. Aren’t there?”
The authors of this book admit that this information is confusing, but there will be examples provided in the next chapter to hopefully clear things up and explain how the quantum enigma came about through experimentation, and finally, we can ponder what it all might mean. There was a LOT of information in this first post, because I didn’t think to summarize what I’ve read until I was seven chapters in. I will make another post after I read the next couple chapters so there is not so much to read in one post. Hopefully the information presented so far has given insight to some, and sparked an interest in learning more. It’s only going to get more interesting from here!
This post is part of a series, for links to other topics click here!