Saturday, June 13, 2015

The Crisis in Cosmology

The Crisis in Cosmology

By Alex Steiner

Lately we are hearing more and more dissident voices from within the community of theoretical physics challenging the dominant view that has defined cosmology for the past 30 years. That paradigm, known as “eternal inflation”, has many variants, but all of them paint a very odd picture of our universe.  The most popular model of eternal inflation hypothesizes that the Big Bang was the start of everything, including Time. The universe was born in a flash –in a trillionth of a trillionth of a trillionth of a second. Even more fantastic is that the inflation which got the ball rolling cannot stop and therefore countless numbers of other universes have since come into existence.  Thus eternal inflation theory argues that we live in a multiverse, i.e., our physical world is just one of countless universes none of which have any interaction with other universes.  This idea, while derived from physics, is in all respects the same as that old chestnut of science fiction stories – the phenomena of parallel universes.  And it is not accidental that some commentators have dubbed the theory of eternal inflation and the multiverse “postmodern physics”. The most radical proponent of the multiverse,  the theoretical physicist Andrei Linde, claims that in fact there is no such thing as a “universe” at all.  The belief in a universe, according to Linde, is little more than a prejudice we have acquired as a result of the limitations of our imagination.   If Linde is right, then the philosophical implications are staggering.  As one writer observed,

If the multiverse idea is correct, then the historic mission of physics to explain all the properties of our universe in terms of fundamental principles—to explain why the properties of our universe must necessarily be what they are—is futile, a beautiful philosophical dream that simply isn’t true. Our universe is what it is because we are here.  [1]

Andrei Linde, supporter of the multiverse thesis 
One might think that such a radical theory of the origins of the universe that has gotten so much support within the community of theoretical physicists comes with an impressive list of observations backing up its findings.  One would think that but one would be wrong.  There is in fact no confirmation of inflation theory and it is arguable whether such confirmation is even possible in principle. [2] Not only that, but the picture of the universe – or multiverse – drawn by inflation theory overturns some very basic ideas about space and time.  If inflation theory is right then the most fundamental concepts that  scientists and philosophers have employed to comprehend the world must be thrown out.  We can no longer even maintain that the totality of everything, the universe as a whole, is a viable concept. If the multiverse hypothesis is true, then we would have to say that there are an infinite number of realities and all of them are in principle “unknowable” except the one we inhabit.  Philosophically, this is a close cousin of the arguments of subjective idealists. 

Both subjective idealists and proponents of a multiverse stake out a claim that there is no single “objective” reality but rather an infinite number of such realities.   The main difference would be that the subjective idealist would identify “reality” with his own subjective experience and suggest that every subject has their own version of reality, one that is unique for each individual.  Since each individual experience is unique and cannot be shared it is therefore impossible in principle to reference a single objective reality common to all. The inflation theorist, on the other hand, while also positing a multitude of possible universes, derives his beliefs, not from an act of reflection on his individual experiences, but from the mathematics of quantum theory.  Rather than identifying reality with experience as the subjective idealists do, inflation theorists are closer to the spirit of Plato and suggest that experiences provide us with but a vague “shadow” of reality.  The Platonic tradition maintains that the underlying structure of reality cannot be grasped by experience but only becomes accessible to us through timeless mathematical laws.  Inflation theorists therefore may seem to be more scientific and more “objective” than the subjective idealists in the tradition of Berkeley.  But despite these differences, the conclusions drawn by inflation theory lead one philosophically into a position not so different than those of the subjective idealists.  For if reality is fragmented into a multiverse there is no longer any philosophical justification for claims about objective reality since it is not at all clear what “objectivity” means in a multiverse.  After all, to put forward the proposition that a multiverse exists implies that somehow we are able to climb outside of our own universe and take a god’s eye view of everything including other universes.  But the ability to step out of our universe is precisely what the multiverse proposition denies.

Alan Guth: founder of eternal inflation theory
The contradictory nature of claims about reality as a whole was first explored by the German philosopher Immanuel Kant in his Antinomies of Pure Reason. An example was Kant’s discussion of the whether the universe had a beginning.  He first assumes that it does have a beginning and from there by a series of logical steps proves that this premise leads to absurdities.  Therefore, by indirect proof, he concludes that the universe could not have had a beginning.  But this opposite premise also leads to absurdities.  So Kant concludes that the question of whether the universe had a beginning or not is an illegitimate question because it asks something that is beyond the limits of our understanding.  Hegel, commenting on this discussion of Kant’s, noted that Kant here came to the very threshold of the dialectic, but like Moses looking out on the Promised Land, could not cross over to it.  Hegel thought that the contradictions introduced by these antinomies can be resolved, but only if one gave up the rigid dichotomies of the understanding that sees a beginning as an absolute point in time completely different than the continuous flux of physical processes. 

The problem that Kant encountered was that the categories that are adequate to explain phenomena when considering a part of reality isolated from the whole break down when one is trying to apply them to the whole. 
Immanuel Kan
A great deal of the progress of modern physics has been as a result of thinking about systems isolated from their larger environment. In that way we can study the effects of certain properties upon other properties while disregarding other factors. This method has been called “doing physics in a box” and in its own terms it is perfectly legitimate. The problem comes in when that method is applied to a study of the universe as whole. This point was eloquently expressed a number of years ago by Stephen Toulmin,

Our cosmological ambitions have, in practice, too often deceived us into accepting fallacious or nonsensical inferences, incautious extrapolations, premature generalizations, or sheer confusion of category.  The whole expanse of Space, for instance, is not just one more volume, which simply happens to be larger than all other volumes.  Nor is the totality of Time just one more historical period, longer than all other periods, but otherwise comme les autres. So we cannot just extrapolate our familiar ideas about smaller regions of space and shorter periods of time and apply them directly to Space and Time “as wholes”. Nor, for that matter, can we use our everyday discoveries about each and every limited particular kind of thing as a secure foundation for conclusions about “the All” or “the Whole.” [3]

 When you theorize about the universe as a whole, the categories that one employs to describe different parts of the universe are no longer adequate and the attempt to conceive of the universe as a whole in terms of those categories leads to contradictions.  This is exactly what Kant discovered in his discussion of the cosmological antinomies.  But he drew the wrong conclusion from it – citing the antinomies as proof that it is illegimate to speculate about the universe as a whole.

Cosmologists have in practice ignored Kant’s injunction since they do think it is legitimate to ask questions about the Universe as a Whole. One of the questions Kant asked, whether the universe had a beginning in Time, is in fact one of the most widely discussed questions among cosmologists today. Hegel, contrary to Kant, maintained that it is legitimate to think about an all inclusive reality -ie. the Universe as a Whole, but that endeavor cannot be successfully accomplished by employing the non-dialectical categories borrowed from thinking about the parts in isolation from the whole.  Contemporary physicists, with few exceptions, have adopted a number of logically incoherent theories in the past few decades, of which eternal inflation is a prime example, because they have not thought through the epistemological and ontological consequences of the models they have developed.

But if we are to take seriously the demands of reason, namely that there is indeed one reality, a universe, an idea that has been the guiding thread of all  scientific and philosophical discovery up till now, then we must conclude that something has gone terribly wrong in the direction of modern physics in the past 30 years.  It seems that physics has become unmoored not only from empirical observation but also from logical coherency. 

And this is precisely the point that a number of dissident voices have begun to raise both within the community of theoretical physics as well as among philosophers who are concerned with fundamental problems of the natural sciences. One of the first of the dissidents was Lee Smolin, who in his 2007 book, The Trouble With Physics, first raised the alarm about the tendency of physicists to ignore fundamental questions of philosophy.  He noted that all the great pioneers of the revolution in physics of the earlier years of the 20th century, Einstein, Bohr, Heisenberg, Planck, were concerned with fundamental philosophical questions and looked to philosophers like Leibniz for insights.  By way of contrast, most of the physicists of the last 50 years have been concerned less with speculation about fundamental laws and concepts than with the resolution of practical problems.  While he grants that both tendencies have made contributions to physics, he thinks that the pendulum has swung too far away from concern with philosophical issues and his book can be viewed as a call to arms for his fellow physicists to return to the concerns that motivated Einstein and the other pioneers of the earlier part of the 20th century. He argued that the near total exclusion of philosophical concerns from theoretical physics has led to a dead end whereby theories are brought forth strictly as a result of their mathematical coherence with no concern for their conceptual or empirical validity.  The result has been in his view the kind of absurdities that Kant exorcised in his Antinomies of Pure Reason. And nowhere are those absurdities more apparent than in the branch of theoretical physics that deals with the universe as a whole, cosmology. 

Lee Smolin, a critic of the turn away from philosophical considerations by physicists
Still another voice raised in opposition to the prevailing views among physicists as well as philosophers of science has been Thomas Nagel’s 2014 book, Mind and Cosmos.  Nagel approached these problems as a philosopher rather than a physicist.  And his focus was not cosmology, but the overall question of how the contemporary philosophy of scientific naturalism conceives of consciousness. He is led to speculate that there is a fundamental inadequacy in the way our current scientific materialist outlook conceives of reality.   His indictment of the near sighted dogma of his fellow philosophers recalls Smolin’s indictment of his fellow physicists. In both cases, there is a recognition of a basic epistemological crisis that hampers further progress.

And just this month, an essay appeared in the online periodical Aeon that once more questions the viability of the paradigm of eternal inflation and suggests that the failure to illuminate speculation about cosmology with the insights gained through the history of philosophy leaves scientists prey to the very same kind of antinomies described by Kant.  The article, In the Beginning, written by Ross Andersen, quotes the dissident physicist Paul Steinhardt, who was one of the pioneers of eternal inflation theory and is today one of its chief critics.

‘The last 30 years is a very unusual period in the history of fundamental physics and cosmology … There’s confusion, and maybe even a certain amount of fear. People are wedded to these ideas, because they grew up with them. Scientists don’t like to change ideas unless they’re forced to. They get involved with a theory. They get emotionally attached to it. When an idea is looking shaky, they go into defensive mode. If you’re working on something besides inflation, you find yourself outside the social network, and you don’t get many citations. Only a few brave souls are willing to risk that.’ [4]

When asked what should be done about this state of affairs, Steinhardt replies,

‘I wish the philosophers would get involved.’

Paul Steinhardt, critic of inflation theory

And this indeed is the issue.  Yet there is a rich tradition in the history of philosophy that offers the kind of conceptual tools contemporary cosmology requires to overcome the paradoxes into which it has become enmeshed.  That tradition is the one identified with philosophers such as Heraclitus, Leibniz, Hegel.  It is the tradition of the dialectical philosophy of nature that was championed by Frederick Engels. It is this tradition that provides the only consistent account of motion and change and provides the necessary corrective to the illusion of an eternal, static and timeless reality first championed by Plato. And in recent years a number of contemporary scientists and philosophers who are reflecting about the Universe as a Whole have turned to that tradition, if not always consciously and deliberately. We will have more to say on this topic on another occasion, but for now we wish to encourage some thinking on these issues. For that reason we are publishing a few excerpts from the recent essay In the Beginning and encouraging readers to follow the link to the entire essay.

[1] The Accidental Universe: Science’s crisis of faith By Alan Lightman, Harpers, December, 2011. 
[2] The sole piece of evidence adduced for it so far is the discovery that the expansion of the universe is accelerating rather than slowing down as previously thought. 
[3] Stephen Toulmin, The Return to Cosmology: Postmodern Science and the Theology of Nature, University of California Press, 1982.  Page 1,2.


In the Beginning

Cosmology has been on a long, hot streak, racking up one imaginative and scientific triumph after another. Is it over?

One crisp day last March, Harvard professor John Kovac walked out of his office and into a taxicab that whisked him across town, to a building on the edge of the MIT campus. People were paying attention to Kovac’s comings and goings that week. He was the subject of a fast-spreading rumor. Kovac is an experimental cosmologist midway through the prime of a charmed career. He did his doctoral work at the University of Chicago and a postdoc at Caltech before landing a professorship at Harvard. He is a blue chip. And since 2009, he has been principal investigator of BICEP2, an ingenious scientific experiment at the South Pole.
Kovac had come to MIT to visit Alan Guth, a world-renowned theoretical cosmologist, who made his name more than 30 years ago when he devised the theory of inflation. Guth told Kovac to take the back steps up to his office, to avoid being seen. If Guth’s colleagues caught a glimpse of the two men talking, the whispers swirling around Kovac would have swelled to a roar.
The science of cosmology has achieved wonders in recent centuries. It has enlarged the world we can see and think about by ontological orders of magnitude. Cosmology wrenched the Earth from the centre of the Universe, and heaved it, like a discus, into its whirling orbit around one unremarkable star among the billions that speed around the black-hole centre of our galaxy, a galaxy that floats in deep space with billions of others, all of them colliding and combining, before they fly apart from each other for all eternity. Art, literature, religion and philosophy ignore cosmology at their peril.
But cosmology’s hot streak has stalled. Cosmologists have looked deep into time, almost all the way back to the Big Bang itself, but they don’t know what came before it. They don’t know whether the Big Bang was the beginning, or merely one of many beginnings. Something entirely unimaginable might have preceded it. Cosmologists don’t know if the world we see around us is spatially infinite, or if there are other kinds of worlds beyond our horizon, or in other dimensions. And then the big mystery, the one that keeps the priests and the physicists up at night: no cosmologist has a clue why there is something rather than nothing.
To solve these mysteries, cosmologists must make guesses about events that are absurdly remote from us. Guth’s theory of inflation is one such guess. It tells us that our Universe expanded, exponentially, a trillionth of a trillionth of a trillionth of a second after the Big Bang. In most models of this process, inflation’s expansive kick is eternal. It might cease in particular parts of the cosmos, as it did in our region, after only a fraction of a second, when inflation’s energy transformed into ordinary matter and radiation, which time would sculpt into galaxies. But somewhere outside our region, inflation continued, generating an infinite number of new regions, including those that are roaring into existence at this very moment.

Not all these regions are alike. Quantum mechanics puts a slot-machine spin on the cosmic conditions of every region, so that each has its own physical peculiarities. Some contain galaxies, stars, planets, and maybe even people. Others are entirely devoid of complex structures. Many are too alien to imagine. The slice of space and time we can see from Earth is 90 billion light years across. Today’s inflationary models tell us that this enormous expanse is only one small section of one tiny bubble that floats along in a frothy sea whose proportions defy comprehension. This vision of the world is wondrous, in its vastness and variety, in the sheer range of possibilities it suggests to the mind. But could it ever be proved?
John Kovac had come to MIT to deliver good news. In 2009, Kovac and colleagues installed a telescope at the bottom of the Earth, and with it caught some of the oldest light in the Universe. He’d come to tell Guth that this light bore scars from time’s violent beginning, scars that strongly suggested the theory of inflation is true.

1 comment:

Donald Cameron said...

Yes a lovey lovely catch. Permanent Revolution

In our model we might define it under "Persistent Hierarchical emergence" in its Modern Living organic context.
The arising inorganic Primitive Complex Mechanisms.
However, given the amount of inorganic waste ....