A Critique Of ‘The Theory Of Everything’

It was only a few weeks before the Laser Interferometer Gravitational-Wave Observatory (LIGO) project announced the detection of gravitational waves that Harry Cliff, a particle Physicist at Cambridge speculated the “End of Physics” in a TED talk that went viral.

It is not the first time that such a prediction has been made about Physics in particular and Science in general. His prediction is based on the lack of any significant findings from another large Physics project, the Large Hadron Collider (LHC), beneath the France-Switzerland border.

The LHC unlike the LIGO was setup to probe the most fundamental particles that make this universe and bring to us discoveries that would help us describe the whole universe based on them. While it has had its share of achievements like the finding of the Higgs Boson in 2012, it has clearly not lived up to its revolutionary expectations.

Cliff, pointing out the huge gaps in fundamental theories of Physics, which the Large Hadron Collider was expected to shed light on, wondered if we have reached the limits of what we could know and if the question why is there something rather than nothing? would forever remain a mystery to humankind. The proposition: if we do not get to know about the fundamental particles that make the universe, how would we derive the universe from them?

It is the premise behind this argument that Dr. Robert B. Laughlin takes on in his book A Different Universe: Reinventing Physics from the Bottom Down. The Nobel laureate in Physics is exasperated at the suggestions that physics has hit its end and sees the obituaries as coming from a certain ‘reductionist’ mindset in the world of physics.

It was in the 1950s that Einstein speculated on a Unified Field Theory, one that would combine his General Theory of Relativity and Quantum mechanics into one grand theory and hence could apply to everything from the microscopic to the cosmic. In the decades that followed, the quest for this ‘Theory of Everything’ accelerated into a Gold Rush, captivating many of the best minds in physics. For many, that seemed the only thing worth pursuing in physics or science.

When formulated, the model of the universe was expected to be so elegant that the simple mathematical equation that would contain it could be written on the front of the ‘t-shirt’. Further, it would enable every phenomenon in the world to be ‘reduced’ back to fundamentals, rendering other fields of science, just the deductions of the first principles of the universe that this theory would provide.

Physics would be built back brick by brick from this theory, chemistry would be constructed from the resulting physics, molecular biology from this chemistry, cellular biology from molecular biology and so on until we could cover psychology, anthropology and even economics.

The most compelling ideas then, were all sitting at the most microscopic or fundamental levels, waiting to be uncovered for the veil on the whole universe to drop. Pursuing them seemed crucial not just for the future of physics but to the future of knowledge itself.

One of the first vocal critiques of this trend in physics was physicist and Nobel laureate P. W. Anderson. In More is Different authored in 1972,  he called into question the basis of this ‘fallacy’ which he believed was the premise that the universe was symmetric and hence could be reduced to a few simple fundamentals. He saw the pursuit essentially as a quest in symmetry and that the universe is what it is not just because of its symmetry but because symmetry is ‘broken’ at multiple levels. Simply put, the universe was ‘something’ rather than ‘nothing’ because of innumerable asymmetries.

Laughlin builds on Anderson’s ideas with simple but pertinent examples in physics such as the Laws of Thermodynamics and Newton’s laws of motion, noting how these fundamental laws are in fact ‘emergent’ properties. The laws of thermodynamics, for example, predict relationships between properties such as pressure, volume and temperature, which are accurate to one in million parts.

But these laws, strangely, completely disappear when one goes to the level of finite number of atoms from which we expect that the condition is built. Laughlin reiterates Anderson’s observation that when increased in scale and complexity, new properties emerge from the collective, which are not explained by its individual components.

There is indeed the apprehension expressed by many scholars that theologians may use the idea of Emergence as a vindication of religious dogmas and unscientific claims. Dr Laughlin elsewhere has noted the attempt to ‘flavour’ the idea of Emergence “with Judeo-Christian understanding” but adds that although there might have been a few early elements of emergent thought in Western philosophy, the Bible is, strictly, ‘top down’ in its approach and has nothing to do with Emergence.

In fact, he notes, the Laws of Physics which should be codifications of the way natural things are, have become the means of their containment. He attributes this to the Judeo-Christian underpinnings of Western thought. In his speech at the Chicago Humanities Festival in 2008, he specifically locates this view as coming from this religious culture:

“To the Western mind it makes perfect sense that the world should be ruled by law, because in fact it is a religious concept. It comes to us from Judaic religion but also it is built into Greek Stoic philosophy which is in turn built into modern Christianity.”

If the ‘top down’ approach is a cultural construct and built so deeply into the Western mind, would it be worthwhile then to ask: Can other civilizations, like India,  have ideas and frameworks that can help question this ‘blind spot’?

Dr Laughlin comes down heavily on speculative theories in physics that are driven by an urge for ‘elegance’. Concepts like string theory, multiverses and super-symmetry that many consider merely speculative, have come to acquire disproportionately more acclaim in popular culture and have come to represent science to majority of lay science enthusiasts. Science, indeed, requires a space for hypothesisation, as the philosopher of science Karl Popper posited long back, pointing out that scientific observation is meaningless without models.

Since then speculation has been considered a genuine part of the scientific method. Laughlin’s exasperation comes from the fact that many of these theories are speculated with no credible experiments predicted to validate (or falsify) them. He exhorts basing physics on what he calls ‘empirical synthesis’, by which I suppose he means a synthesis based on the primacy of experimental validation and not ‘inductivism’ that Popper so convincingly refuted.

In this context, it is interesting to note how Stephen Hawking has asserted that the ‘M Theory’ (of String Theory) was the “unified theory Einstein was hoping to find” incredibly suggesting that it needs a “bigger Hadron Collider the size of the Milky Way” to ‘prove’ it, practically putting its experimental validation or even corroboration beyond the realm of human reach. This indeed has been the state of the hypotheses and theories that have been chasing the ‘Theory of Everything’. Many physicists have even started asking if ‘falsification’ is too strict a criteria for arbitration for scientific ideas.

The ‘reductionist’ mindset seems to have created a sense of inevitability about this single fundamental theory, the discovery of which is seen to render everything else derivable from it and its non-discovery would lead to complete paralysis. Either way, the ‘end of physics’ is seen coming. It would probably need a shift in the way we see physics, as suggested by Dr Laughlin, to break out of the impasse created by this dichotomy.

He believes that, if anything it would be the ‘end of reductionism’ and not the ‘end of physics’. The universe, he believes, still has a lot of secrets and surprises to offer and one need not go only to the microscopic or fundamental levels to find them. The frontiers of science, to him, are right under our fingers.