As somebody said, science is what scientists do. And scientists are human too. Some of these humans have great difficulty in reconciling what science tells them with what they learnt from various sources when they were young and impressionable. So they may unconsciously look for ‘loopholes’ in the scientific premises and reasoning, particularly when it comes to fundamental questions about life, mind, and the universe.
In science there is always a cutting edge, or the frontier line where things are hazy. There is debate among experts as various alternative models are compared and contrasted. The beauty of the scientific method is that it is ruthless and without regard for authority (but see below!). Truth prevails ultimately, sometimes after a prolonged debate about what is the best way of interpreting the available data. When more data come in, science has no difficulty in dumping even its most cherished theories if necessary.
Sometimes, of course, the debate continues endlessly. This is particularly true for the highly counterintuitive quantum theory. To me the most important thing about this theory is that it has been phenomenally successful in explaining a vast multitude of natural phenomena, even though we do not have all the answers. Science accepts it because there is no better theory known to us that can be more successful for explaining what we see in the world around us.
To me it is not important that the quantum theory is counterintuitive. I see no reason why the laws of Nature should be always comprehensible to us. We emerged on the cosmic scene very very recently, but the laws of Nature have been there all the time.
But, as I said, scientists are human too. They do have their failings and weaknesses and gut feelings. We all know about Einstein’s reservations about the quantum theory of his day. His views fell by the wayside. But tomorrow if Einstein turns out to be right, no problem. We would then have an even better theory at hand. That is how science progresses.
2. The Copenhagen interpretation
There was this well-known debate between Einstein and Bohr about the foundations of quantum mechanics. Bohr’s viewpoint prevailed, and this gave him enormous, even undue, authority in scientific circles. If a proof is needed, look at the so-called ‘Copenhagen interpretation’ (CI) of quantum mechanics he gave in 1927, jointly with Heisenberg (another venerated scientist). According to the CI, people and the equipment they use exist in a classical world which is different from the quantum world. A quantum state is a superposition of two or more states, but when it interfaces with the classical world (at the moment of measurement), there is a collapse of the wave function (randomly) to one of the alternatives, and the other alternatives disappear. The CI was put in ‘by hand’ as an additional postulate of quantum mechanics.
I have given some more details of the CI in an article on ‘biocentrism’ I coauthored with Ajita Kamal, published here.
What was done there was to juxtapose the CI with a number of later interpretations. To me it is clear that the CI has been superseded by better interpretations.
So much for science. Now let us look at the scientists part of it.
Among the earliest persons to openly challenge the CI was Hugh Everett III, when he put forward his ‘many worlds’ interpretation. But on the scientific scene at that time he was just a kid (a student at Princeton University in the mid-1950s) compared to stalwarts like Bohr and Heisenberg. [To us in India this is reminiscent of the Chandrasekhar vs. Eddington episode in cosmology.] A. H. Wheeler was the Ph.D. supervisor of Everett. Peter Byrne has written about this story in an article in the December 2007 issue of Scientific American. In 1956 Wheeler took the draft dissertation of Everett to Copenhagen to convince the Royal Danish Academy of Sciences to accept it and publish it. He had ‘three long and strong discussions about it’ with Bohr and Petersen. He also showed the work to many others at the Bohr Institute for Theoretical Physics, including A. S. Stern.
Stern dismissed the work as ‘theology,’ and Wheeler himself was reluctant to challenge Bohr. The thesis had to be whittled down to a quarter of its original length. This abridged version also appeared in Reviews of Modern Physics. Young Everett eagerly looked forward to the reactions of the physics community. All he got was stony silence, such was the awe that the name Bohr inspired (and that continues in some quarters even today). Discouraged, Everett left physics and worked on military and industrial mathematics and computing. As the Editors of Scientific American wrote, ‘He died when he was just 51, not living to see the recent respect accorded to his ideas by physicists.’
Bohr, of course, was quite consistent in his views about the basics and limitations of quantum mechanics. This came to the fore again in his reaction to Einstein’s and others’ views on ‘quantum entanglement.’ Now this is another esoteric feature of quantum mechanics that challenges our intuition very seriously. And yet there is no immediate danger to the present edifice and acceptability of quantum theory. Why? The answer comes from experiment, namely the fact that quantum computing is already a reality.
The entanglement feature of quantum mechanics is about the spooky ‘action at a distance’: Two particles behave synchronously without any intermediary, no matter how far apart they are. This nonlocalityfeature bothered Einstein and others, as embodied in the famous EPR (Eistein-Podolsky-Rosen) thought experiment published in 1935 in a paper with title ‘Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?’ EPR argued that the answer to the question is ‘No.’ They took the position that nonlocality is not something real, and therefore quantum mechanics does not provide a complete description of reality.
Bohr did agree with this conclusion, but for his own reasons (see, for example, the article by Albert and Galchen in the March 2009 issue of Scientific American). He argued that we should not even try to read from the equations of quantum mechanics a realistic comprehension of the world. This was in line with what he did in the Copenhagen interpretation mentioned above; namely, introduce one morepostulate or axiom by hand when interfacing the microworld with the macroworld.
Thirty years later John Bell wrote his famous paper in which he established by mathematical proof that the real physical world is indeed nonlocal, no matter what EPR or Bohr believed to be the case. He showed that no local (as opposed to nonlocal) theory can reproduce all the predictions of quantum mechanics because the predictions must always satisfy the now-famous Bell’s inequalities. This meant that the concept of locality was indeed incompatible with quantum theory, so the actual physical world in indeed nonlocal. Both Einstein and Bohr were wrong, though for different reasons.
The influence of Bohr’s line of thinking was so strong and persistent that there was resistance to Bell’s work also. But this situation has changed gradually. I quote from Albert and Galchen (2009): ‘From the early 1980s onward, the grip of Bohr’s conviction — that there could be no old-fashioned, philosophically realistic account of the subatomic world — was everywhere palpably beginning to weaken.’
4. Ockham’s razor
The philosopher Ockham advocated the use of simplest possible explanations for natural phenomena: ‘Plurality should not be posited without necessity‘. The proverbial Ockham’s razor cuts away complicated and long explanations. Ockham declared that simple explanations are the most plausible.
In science, as also in mathematics, we always have some axioms to start with, from which we derive theorems etc. Axioms are something we accept without questioning. If we choose wrong axioms, we get theorems which contradict experiment, so this is not so serious a problem because it is self-correcting. The more serious problem is: How many axioms we should choose?
An extreme situation is wherein we ‘explain’ everything in terms of axioms only, so we have a huge number of axioms, and there is no theory worth the name. Leibniz (1675) was amongst the earliest known investigators of this situation. He argued that a worthwhile theory of anything has to be ‘simpler than’ the data it explains. Otherwise, either the theory is useless, or the data are ‘lawless’. The criterion ‘simpler than’ is best understood in terms of information theory, particularly its more recently developed offshoot, namely algorithmic information theory (AIT).
Gregory Chaitin is a pioneer of AIT. To understand the essence of the AIT, consider a very simple example. Take the set of all positive integers, and ask the question: How many bits of information are needed to specify all these integers? The answer is an absurdly large number. But the fact is that this set of data has very little information content. It has a structure which we can exploit to write an algorithm which can generate all the integers, and the number of bits of information needed to write the algorithm is indeed not large. So the algorithmic information content in this problem is small.
One can generalize and say that, in terms of computer algorithms, the best theory is that which requires the smallest computer program for calculating (and hence explaining) the observations. The more compact the theory, the smaller is the length of this computer program. Chaitin’s work has shown that the Ockham razor is not just a matter of philosophy; it has deep algorithmic-information underpinnings. If there are competing descriptions or theories of reality, the more compact one has a higher probability of being correct. Ockham’s razor cuts away all the flab. Let us see why.
In AIT, an important concept is that of algorithmic probability (AP). It is the probability that a random program of a given length fed into a computer will give a desired output, say the first million digits of π. Following Bennett and Chaitin’s pioneering work done in the 1970s, let us assume that the random program has been produced by a monkey. The AP in this case is the same as the probability that the monkey would type out the same bit string, i.e. the same computer program as, say, a Java program suitable for generating the first million digits of π. The probability that the monkey would press the first key on the keyboard correctly is 0.5. The probability that the first two keys would be pressed correctly is (0.5)2 or 0.25. And so on. Thus the probability gets smaller and smaller very rapidly as the number of correctly sequenced bits increases. The longer the program, the less likely it is that the monkey will crank it out correctly. This means that the AP is the highest for the shortest programs or the most compact theories. The best theory has the smallest number of axioms.
In the present context, suppose we are having a bit string representing a set of data, and we want to understand the mechanism responsible for the creation of that set of data. In other words, we want to discover the computer program (or the best theory), among many we could generate randomly, which is responsible for that set of data. The validation of Ockham’s philosophy comes from the fact that the shortest such program is the most plausible guess because it has the highest AP.
In the Copenhagen interpretation described above, Bohr’s action of adding one more postulate or axiom by hand was unwarranted, as later developments in quantum theory have demonstrated.
The narrative so far is enough to illustrate the difficulties we humans face in understanding the nature of reality with our limited collective intellect and other resources. But fortunately we scientists have with us the power of the scientific method of enquiry, which is no respecter of authority. As Bell’s work has shown, both Einstein and Bohr held wrong views about nonlocality. Good science is self-correcting.
There is so much that science cannot answer. But the big question is: Is there ANY other way of getting these answers? No. There is none.
Some questions are indeed very difficult to answer, but scientists keep trying. The incremental progress may be slow, but there is progress nevertheless.
The unfortunate fact of life is that not many humans have the requisite training and mental discipline demanded by the scientific method. They MUST have an answer always. If science cannot provide it at present, they do not have the patience to wait. They just invent answers by introducing more and more axioms (incidentally, this is what is done by most religions). Here is an example.
Deepak Chopra, a medical doctor, who also uses at times the language of quantum mechanics in his discourses and writings, posted an article on the Huffington Post. Here is an excerpt:
‘I consider myself scientific at heart, and so I depend upon a theory as well. Its basic premises are as follows:
- We live in a universe that exhibits intelligence, self-regulation, and creativity.
- Consciousness preceded the brain. It created life and went on to create the brain itself.
- Consciousness is primary in the world; matter is secondary.
- Evolution is conscious and therefore creative. It isn’t random.
- At the source of creation one finds a field of pure awareness.
- Pure awareness is the source of every manifest quality in the universe.’
Anybody is welcome to subscribe to a theory of his/her choice. My response to the above statements is as follows:
- It is only a belief.
- What is the basis for making this assertion?
- Again just a belief.
- Prove it.
- Just wishful thinking.
- That’s what YOU think.
What can any scientist do with the kind of ‘theory’ Chopra subscribes to? I want to invoke Ockham’s razor. If you introduce as many axioms or premises as Chopra wants to, then there is just about nothing left to be derived from those axioms. Practically everything is axiomatic in this ‘theory.’ Ockham’s razor will make mincemeat of Chopra’s set of premises!
Chopra goes on to give a list of questions which science cannot answer at present. So what? Is there ANY better way of getting those answers?
If somebody is a mystic, I have no problem with that. What is not acceptable is peddling mysticism under the garb of science, or rather pseudoscience. And one cannot be ‘scientific at heart’ and yet be innocent about the rigours of the scientific method of acquiring knowledge and understanding.
Chopra uses the word ‘consciousness’ again and again. I draw the attention of the reader to my article here.
As I argue there, it is not possible to define consciousness in an unambiguous scientific way. How do we discuss it and investigate it when there is no agreement on what that word really means?
There is nothing sacrosanct about the set of axioms and premises on which modern science is based. Any other set of axioms can be fine if it leads to theorems and conclusions and intellectual progress better than what the existing science has achieved. Deepak Chopra’s set of premises is quite typical of the thinking to which even some scientists subscribe. These people usually are apologists for their religious beliefs. I want to suggest something to them. Why not try to build up the edifice of a self-consistent parallel science based on such axioms? Take the axioms of your choice, and take as many as you want (or rather as few as you can), and see if you can produce something superior to the existing scientific framework. If you succeed, I shall be the first one to proudly walk over to your camp. Why only me? The whole of the existing structure of science will just fade away, because it would have been superseded by something superior.
6. Concluding remarks
- The scientific method is among the greatest achievements of the human mind.
- Science is impersonal, but scientists are not. Scientists come in all shapes, sizes, conditionings, egos, and biases. Their subjectivity does slow down the progress of science, but not for long. Ultimately the best theory prevails.
- Even the best scientific theory holds only till a better one comes along. Scientists have no compunction about dumping their pet theories in favour of better ones. This is true intellectual humility, not commonly seen in non-scientific or unscientific circles.
- All those who love and respect science should try to ensure that it is not hijacked by pseudoscientists to meet their covert or overt agendas.
- Some questions are inherently very difficult to answer. But there is NO method other than the scientific method for getting the answers.