Prof S. M. Deen [University of Keele, England] Eid al-Fitre day, Friday, 10 Sept, 2010
Prof Stephen Hawking is the most well-known British physicist whose recent book denying the existence of God has created a flurry of discussions. Here are the issues.
In his earlier book A Brief History of Time, he seemed to have accepted the existence of God as the Creator, as in Deism – a philosophy subscribed to by Einstein and many other scientists. But in his new book The Great Design written jointly with Leonard Mlodinow, he stated that we do not need any God to explain the creation of the universe, since the M-String theory has dispensed with God. This theory has come after the publication of his earlier book. So, what has happened in physics and what is this String Theory?
The Problem of a Single Universe
The universe as we know it has some special features whose origins cannot be explained by physics. For example, why the strength of the force of gravity, or that of electo-magnetive field (force) is what they are? If these strengths are more than fractionally different from what they are, then this universe will not exist, and hence we will not be here. To take another example, if the mass of neutron is 1% less than what it is, then again there cannot be this universe. There are around 19 or so such critical constants which if were different by more than a fraction from what they are, then this universe and we would not have existed. So it seems (from physics point of view) that the universe is specially created by someone for us to evolve and exist. This is why Einstein wanted to ask God (i.e. if he had a chance), if He had a choice when He created the universe. This idea that the universe is designed in such a way that it is just right for the creation of life is called anthropic principle (strictly speaking, this term is a misnomer, since anthropic refers to human, but the cosmologists use it to refer to all living things). Specifically, for life to exist in some place in a universe the following basic conditions must be satisfied:
- The laws of physics must permit stable complex structures to form
- The universe must posses the right kind of substances, e.g, carbon
- The appropriate initial conditions and settings must exist in the right way
I shall not elaborate these conditions here (as I want to keep this article brief), leaving it to you to wonder on the complexity needed from the point of view of physics.
There has been an idea of multiple universes for some time. If instead of a single universe, there are infinite number of universes, then there would be universes with all varieties of science laws (and their constants). In that scenario, we happened to be living in one universe (our universe), which has just the right laws (and constants) of physics, chemistry and biology. This would solve the problem of uniqueness, but is there any evidence that multiverses exist? After all, in physics (as in all sciences) you need evidence for your assertion.
However, we now have a new theory called M-String Theory (see the piece below for more detail, with apologies to those of you who have received it from me before), which supports multiple (perhaps an infinite number of) universes. This theory is also controversial among many physicists, who find it too speculative, with much complex mathematics, but without any shred of evidence that any of these is sound. Also many parts of the theory are still undeveloped. Since this theory advocates multiple universes, Stephen Hawking asserts that there is no need for God any more, even though (I stress) there is no evidence that this theory is valid, not to speak of the fact that the theory is incomplete and is rejected by many renowned physicists as too speculative.
However it is still possible that multiverses exist. Recently scientists at NASA have discovered something they called "Dark Flow" (not to be confused with Dark Energy or Dark Matter). This Dark Flow could be an indication that multiverses exist [much further work is needed here]. So where are we:
Let me take you back to physics of vacuum and forces in this universe of ours. What we call vacuum is not empty. It always has natural forces (e.g. gravity, electromagnetic force, strong interaction, weak interaction) acting on this vacuum. In it subnuclear particles are constantly bubbling (subject to Quantum laws), some being created and others being annihilated, such that the average is zero (and hence it is defined as vacuum). This situation has been found to be true by experiments long ago (if you are interested, this idea of bubbling vacuum played a role in the discovery of positron in the 1930s). Therefore, we conclude that vacuum in our part of the universe (not to speak of other universes) is nonempty with subnuclear particles bubbling under some force-fields.
Now we return to the early universe (or multiverse), i.e. before the supposed Big Bang, when there was a vacuum. That vacuum also had a force-field (precursor of the forces I have listed in the previous paragraph). In that vacuum, equivalents of particles were bubbling (quantum fluctuations) all the time under that primordial force-field, from which came the Big Bang etc that created the universe (one or more). So who created that force-field, all that bubbling, and all laws that led to the manifestation of all creations, one universe or infinite number of universes, and their content. Stephen Hawking does not answer this vital question, as most physicists would agree with me. You need a creator even if the multiverse hypothesis is correct.
What should we Muslim scientists do? What Al-Kindi (d. 870 CE) said in his time is still true today, and this can be restated as: It is our duty to uncover the mystery of God's creation and thus to create a society flourishing in science and knowledge.
String Theory and Computer Model
The latest version is the M-String Theory (MST). in which every thing is made up of two-dimensional (2D) strings, which vibrate with different frequencies in a 11-D universe for different elementary particles. We can understand a string vibrating, which 1-diemensional [1D]. A 2D vibration means a piece of plane vibrating. The universe has 11-D, of which we can experience only four [say forward-backward (x), right-left (y), up-down (z) and time (t)]. Now consider the following:
If we move in the x-direction say walk forward in a straight-line on the surface of this earth, then after some 25,000 miles, we shall be back at our starting point. Now let us suppose the size of the earth is smaller than a grain of sand. In that case, we cannot walk on its surface towards any direction (say x-direction), since its extent is too small (we are too big for it). This is the case with the other seven dimensions of the universe, their extents are too small (much smaller than a grain of sand), and hence these are called "curled up" dimensions in MST. Therefore, and in that sense, those seven curled-up dimensions do not effect our (human) daily life.
So we live in an apparent 4-D world, even though the universe is 11-D. Therefore our 4-D scenario is a projection (i.e. a subset) of an 11-D universe, in the same way that the sun looks like a 2D disc, even though it is a sphere. To derive that subset correctly, we need to calculate (using mathematics). These calculations have to be dynamic and continuous, as we each perceive and do things continuously. How can we understand this 4-D projection from the real 11-D universe? For this, we can imagine a giant cosmic computer, with an appropriate computer model, that continually produces our apparent 4-D universe from the real 11-D one for each of us. Thus the cosmic computer and its model is an analogy to understand the theory, it is not part of the theory.
There are certain properties in physics, which are very difficult to understand. This includes quantum mechanics. A most fundamental of this is why there is just this single universe? Laws of physics do not point to a single universe. If we accept that there are multiple universes (multiverse), then many of these theoretical problems (including the anthropic problems I have mentioned earlier) disappear. Some string theorists support an infinite number of universes, many universes being created (or annihilated by collisions/instability) at every time-instant. However there is no evidence that this speculation on multiverses is true. There are debates on whether we could ever have evidence (despite Dark Flow) to prove or disprove this idea of multiverses. Perhaps the expected experiments with the Large Hadron Collider (LHC) at CERN (
) will provide some evidence in one way or another, not only for multiverses but also for MST (or am I too optimistic?). Now in physics, if you cannot prove an idea by evidence, then the idea must be dropped at the end. Geneva
Note many well-known physicists think that the String Theory is too much of a stodgy mathematical speculation. Some of them even assert that it is not physics at all, it is just jugglings with higher mathematics. So far the theory has not been able to provide any prediction that can be tested by experiment [a fundamental requirement for any theory to be considered in physics]. Therefore these physicists do not believe in this theory.
Finally these days, many physicists are coming to the conclusion that we humans may never be able to understand some of these mysterious issues (including how the human brain creates consciousness). As the Quran [02: 02/03] implies: we shall never understand everything, there being things beyond our perception (gaib).
[I am currently producing a discussion document for a group of retired-professors (including physicists) on Dark Flow. Would you be interested?]