Paying Attention To The Sky

Quantum physics, which originated in work conducted by Max Planck and Albert Einstein at start of 20th Century, is a hugely successful theory: the predictions it makes about the behavior of subatomic particles are extraordinarily accurate. And yet, it raises profound puzzles about reality that remain as yet to be understood. Niels Bohr once said if quantum mechanics hasn’t profoundly shocked you, you haven’t understood it yet.

In quantum mechanics any situation is a blend of every possible option of what might happen and this blend is called a wave function. This seems to work for light. Sometimes light can act as a particle and sometimes as a wave. Atoms, it has been found, seem to follow the same rules. As the world is made of atoms, the world must follow the rules of quantum mechanics. Obviously in the real world life doesn’t spend its time sitting on the fence, things just happen. But in quantum mechanics things happen only when this wave function collapses and only one possibility is left.

At some point a situation has to stop having every possible outcome. When an event is observed then all the other possibilities suddenly disappear. It’s like saying that the universe is based on chance. One enormous casino. What happens next is based on chance not on an absolute certainty. Imagine the universe as a horse race with lots of evenly matched horses. Until the race is over you can’t tell which horse is going to win. With quantum mechanics the idea is that the race isn’t over until someone decides to check on the result. This is where the science fiction idea of ‘parallel universes’ comes from. If every possible outcome is waiting to happen perhaps it really does happen in another quantum universe. Every horse wins in some reality.

Erwin Schrödinger was the man who first discovered the equations that quantum mechanics relies on. Even he couldn’t believe the idea that nothing happens until someone looks to check it. He invented the most famous cat in science – Schrödinger’s cat. If nothing happens until it is observed then imagine the following. A cat is put in a box with a small gadget that will release poison. This poison will be released by something that is controlled by the laws of quantum mechanics, for example radioactive decay. Radioactive atoms are ones that are unstable and spontaneously break down into smaller atoms. So there is a lump of radioactive material and a device to detect if an atom has broken down. This atomic break-up has a 50:50 chance of happening in one hour. According to quantum mechanics, until the box is opened an hour later both outcomes should co-exist. The cat should be both dead and alive at the same time until someone observes the result.

Despite what some people think, this story was meant to show how Niels Bohr’s interpretation of quantum mechanics was wrong. It was just an interpretation. There is an easier way of thinking about this. Quantum mechanics does seem to explain a lot of things about atoms and light. This craziness of a cat that is both dead and alive only applies if you stick to the idea that everything happens until it is measured by a person. There is no paradox if you just change to the idea that a quantum event happens when the result interacts with anything. When the radioactive atom in the box decays, the cat will only die when the radioactivity detector in the box detects it. When a particle that follows quantum mechanics interacts with anything it has to commit to being one thing or another. So a quantum mechanic event can set up a sequence of events that end up with a cat that is dead or alive without needing it be both at the same time.

All this cat really tells us about quantum mechanics is that trying to use quantum mechanics to explain normal day-to-day life doesn’t work. Understanding atoms doesn’t help you understand a whole cat, but then again understanding cats doesn’t help you understand atoms, so it works both ways (no matter what cats say). Einstein’s problem with quantum mechanics was summed in the idea that ‘God doesn’t play dice’. Everyone seems to remember that but do you know not what Niels Bohr said in reply: “It is not the job of scientists to prescribe to God how he should run the world.” (Some excellent advice, were that more of his fellow scientists followed it instead of penning best sellers on atheism.) 

At the end of the day quantum mechanics does make sense in its own realm and offers explanations for strange effects that have no other explanation. In the traditional interpretation of quantum theory –sometimes also called the “Copenhagen,” “standard,” or “orthodox” interpretation — one must, to avoid paradoxes or absurdities, posit the existence of so-called “observers” who lie, at least in part, outside of the description of the world provided by physics. That is, the mathematical formalism which quantum theory uses to make predictions about the physical world cannot be stretched to cover completely the person who is observing that world. What is it about the “observer” that lies beyond physical description? Careful analysis suggests that it is some aspect of the rational mind.

This has led some eminent physicists to say that quantum theory is inconsistent with a materialistic view of the human mind. Eugene Wigner, a Nobel laureate in physics, stated flatly that materialism is not “logically consistent with present quantum mechanics.” Sir Rudolf Peierls, another leading twentieth–century physicist, said, on the basis of quantum theory, “The premise that you can describe in terms of physics the whole function of a human being…including its knowledge, and its consciousness, is untenable. There is still something missing.”

Admittedly, this is a highly controversial view. That is only to be expected, especially given the materialist prejudice that affects a large part of the scientific community. Moreover, the traditional interpretation of quantum theory has aspects that many find disturbing or implausible. Some even think (wrongly, in Dr. Steven Barr’s opinion) that the role it assigns to observers leads to subjectivism or philosophical idealism. Dissatisfaction with the traditional interpretation has led to various rival interpretations and to attempts to modify quantum theory. However, these other ideas are equally controversial. The controversy over quantum theory will not be resolved any time soon, or perhaps ever. But, even if it is not, the fact will remain that there is an argument against materialism that comes from physics itself, an argument that has been advanced and defended by some leading physicists and never refuted.

Recently the Templeton Prize, awarded for contributions to “affirming life’s spiritual dimension”, has been won by French physicist Bernard d’Espagnat, who has worked on quantum physics with some of the most famous names in modern science. d’Espagnat says a spiritual reality is veiled from us, and science offers a glimpse behind that veil. The bizarre nature of quantum physics has attracted some speculations that are wacky but the theory suggests to some serious scientists that reality, at its most basic, is perfectly compatible with what might be called a spiritual view of things. Some suggest that observers play a key part in determining the nature of things. Legendary physicist John Wheeler said the cosmos “has not really happened, it is not a phenomenon, until it has been observed to happen.”

D’Espagnat worked with Wheeler, though he himself reckons quantum theory suggests something different. For him, quantum physics shows us that reality is ultimately “veiled” from us. The equations and predictions of the science, super-accurate though they are, offer us only a glimpse behind that veil. Moreover, that hidden reality is, in some sense, divine. Along with some philosophers, he has called it “Being”.

The deeper questions in physics are bound to interact with the religious/philosophical assumptions of the physicist. So how do scientists investigating the fundamental nature of the universe assess any role of God? Mark Vernon, who writes science articles, did a little research and came up with the following:

1. THE ATHEIST

Nobel-prize winning physicist Steven Weinberg is well-known as an atheist. For him, physics reflects the “chilling impersonality” of the universe. He would be thinking here of, say, the vast tracts of empty space, billions of light years across, that mock human meaning. He says: “The more the universe seems comprehensible, the more it seems pointless.”

So for Weinberg, the notion that there might be an overlap between science and spirituality is entirely mistaken: “I have to admit that, even when physicists will have gone as far as they can go, when we have a final theory, we will not have a completely satisfying picture of the world, because we will still be left with the question ‘why?’ Why this theory, rather than some other theory? For example, why is the world described by quantum mechanics? Quantum mechanics is the one part of our present physics that is likely to survive intact in any future theory, but there is nothing logically inevitable about quantum mechanics; I can imagine a universe governed by Newtonian mechanics instead. So there seems to be an irreducible mystery that science will not eliminate.

But religious theories of design have the same problem. Either you mean something definite by a God, a designer, or you don’t. If you don’t, then what are we talking about? If you do mean something definite by ‘God’ or ‘design,’ if for instance you believe in a God who is jealous, or loving, or intelligent, or whimsical, then you still must confront the question ‘why?’ A religion may assert that the universe is governed by that sort of God, rather than some other sort of God, and it may offer evidence for this belief, but it cannot explain why this should be so.”

2. THE SKEPTIC

The Astronomer Royal and President of the Royal Society, Martin Rees, shows a distinct reserve when speculating about what physics might mean, whether that be pointlessness or meaningfulness. He has “no strong opinions” on the interpretation of quantum theory: only time will tell whether the theory becomes better understood. “The implications of cosmology for these realms of thought may be profound, but diffidence prevents me from venturing into them,” he has written. In short, it is good to be humble in the face of the mysteries that physics throws up.

3. THE PLATONIST

Oxford physicist Roger Penrose differs again. He believes that mathematics suggests there is a world beyond the immediate, material one. Ask yourself this question: would one plus one equal two even if I didn’t think it? The answer is yes. Would it equal two even if no-one thought it? Again, presumably, yes. Would it equal two even if the universe didn’t exist? That is trickier to contemplate, but again, there are good grounds for a positive response. Penrose, therefore, argues that there is what can be called a Platonic world beyond the material world that “contains” mathematics and other abstractions.

4. THE BELIEVER

John Polkinghorne worked on quantum physics in the first part of his career, but then took up a different line of work: he was ordained an Anglican priest. For him, science and religion are entirely compatible. The ordered universe science reveals is only what you’d expect if it was made by an orderly God. However, the two disciplines are different. He calls them “intellectual cousins”. “Physics is showing the world to be both more supple and subtle, but you need to be careful,” he says. If you want to understand the meaning of things you have to go beyond science, and the religious direction is, he argues, the best.

5. THE PANTHEIST

Brian Swimme is a cosmologist, and with the theologian Thomas Berry, wrote a book called The Universe Story: From the Primordial Flaring Forth to the Ecozoic Era. It is avidly read by individuals in New Age and ecological circles, and tells the scientific story of the universe, from the Big Bang to the emergence of human consciousness, but does so as a new sacred myth. Swimme believes that “the universe is attempting to be felt”, which makes him a pantheist, someone who believes the cosmos in its entirety can be called God.

The simple explanations of quantum theory come from a kids’ science blog called “journeybystarlight.”

The final post from Dr. Barr is here:

http://payingattentiontothesky.com/2009/05/27/annals-of-atheism-v-the-scientist-debunking-himself/