Showing posts with label cosmology. Show all posts
Showing posts with label cosmology. Show all posts

Monday 12 September 2022

The Uncaused Multiverse: And What It Signifies


By Keith Tidman

Here’s an argument that seems like commonsense: everything that exists has a cause; the universe exists; and so, therefore, the universe has a cause. A related argument goes on to say that the events that led to the universe must themselves ultimately originate from an uncaused event, bringing the regress of causes to a halt.

But is such a model of cosmic creation right?


Cosmologists assert that our universe was created by the Big Bang, an origin story developed by the Belgian physicist and Catholic priest Georges Lemaitre in 1931. However, we ought not to confuse the so-called singularity — a tiny point of infinite density — and the follow-on Big Bang event with creation or causation per se, as if those events preceded the universe. Rather, they were early components of a universe that by then already existed, though in its infancy.

It’s often considered problematic to ask ‘what came before the Big Bang’, given the event is said to have led to the creation of space and time (I address ‘time’ in some detail below). By extension, the notion of nothingness prior to the Big Bang is equally problematic, because, correctly defined, nothingness is the total, absolute absence of everything — even energy and space. Although cosmologists claim that quantum fluctuations, or short bursts of energy in space, allowed the Big Bang to happen, we are surely then obliged to ask what allowed those fluctuations to happen.

Yet, it’s generally agreed you can’t get something from nothing. Which makes it all the more meaningful that by nothingness, we are not talking about space that happens to be empty, but rather the absence of space itself.

I therefore propose, instead, that there has always been something, an infinity where something is the default condition, corresponding to the impossibility of nothingness. Further, nothingness is inconceivable, in that we are incapable of visualising nothingness. As soon as we attempt to imagine nothingness, our minds — the act of thinking about it — causes the otherwise abstraction of ‘nothingness’ to turn into the concreteness of ‘something’: a thing with features. We can’t resist that outcome, for we have no basis in reality and in experience that we can match up with this absolute absence of everything, including space, no matter how hard we try to picture it in our mind’s eye.

The notion of infinity in this model of being excludes not just a ‘first universe’, but likewise excludes a ‘first cause’ or ‘prime mover’. By its very definition, infinity has no starting point: no point of origin; no uncaused cause. That’s key; nothing and no one turned on some metaphorical switch, to get the ball rolling.

What I wish to convey is a model of multiple universes existing — each living and dying — within an infinitely bigger whole, where infinity excludes a ‘first cause’ or ‘first universe’.

In this scenario, where something has always prevailed over nothingness, the topic of time inevitably raises its head, needing to be addressed. We cannot ignore it. But, I suggest, time appears problematic only because it's misconceived. Rather, time is not something that suddenly lurches out of the starting gate upon the occurrence of a Big Bang, in the manner that cosmologists and philosophers have typically described how it happens. Instead, when properly understood, time is best reflected in the unfolding of change.

The so-called ‘arrow of time’ traditionally appears to us in the three-way guise of the past leading to (causing) the present leading to the future. Allegorically, like a river. However, I propose that past and future are artificial constructs of the mind that simply give us a handy mechanism by which to live with the consequences of what we customarily call time: by that, meaning the consequences of change, and thus of causation. Accordingly, it is change through which time (temporal duration) is made visible to us; that is, the neurophysiological perception of change in human consciousness.

As such, only the present — a single, seamless ‘now’ — exists in context of our experience. To be sure, future and past give us a practical mental framework for modeling a world in ways that conveniently help us to make sense of it on an everyday level. Such as for hypothesising about what might be ahead and chronicling events for possible retrieval in the ‘now’. However, future and past are figments, of which we have to make the best. ‘Time reflected as change’ fits the cosmological model described here.

A process called ‘entropy’ lets us look at this time-as-change model on a cosmic scale. How? Well, entropy is the irresistible increase in net disorder — that is, evolving change — in a single universe. Despite spotty semblances of increased order in a universe — from the formation of new stars and galaxies to someone baking an apple pie — such localised instances of increased order are more than offset by the governing physical laws of thermodynamics.

These physical laws result in increasing net disorder, randomness, and uncertainty during the life cycle of a universe. That is, the arrow of change playing out as universes live and peter out because of heat death — or as a result of universes reversing their expansion and unwinding, erasing everything, only to rebound. Entropy, then, is really super-charged change running its course within each universe, giving us the impression of something we dub time.

I propose that in this cosmological model, the universe we inhabit is no more unique and alone than our solar system or beyond it our spiral galaxy, the Milky Way. The multiplicity of such things that we observe and readily accept within our universe arguably mirrors a similar multiplicity beyond our universe. These multiple universes may be regarded as occurring both in succession and in parallel, entailing variants of Big Bangs and entropy-driven ‘heat deaths’, within an infinitely larger whole of which they are a part.

In this multiverse reality of cosmic roiling, the likelihood of dissimilar natural laws from one universe to another, across the infinite many, matters as to each world’s developmental direction. For example, in both the science and philosophy of cosmology, the so-called ‘fine-tuning principle’ — known, too, as the anthropic principle — argues that with enough different universes, there’s a high probability some worlds will have natural laws and physical constants allowing for the kick-start and evolution of complex intelligent forms of life.

There’s one last consequence of the infinite, uncaused multiverse described here. Which is the absence of intent, and thus absence of intelligent design, when it comes to the physical laws and materialisation of sophisticated, conscious species pondering their home worlds. I propose that the fine-tuning of constants within these worlds does not undo the incidental nature of such reality.

The special appeal of this kind of multiverse is that it alone allows for the entirety of what can exist.

Monday 17 August 2020

And the Universe Shrugged




Posted by Keith Tidman

It’s not a question of whether humankind will become extinct, but when.

To be clear, I’m not talking about a devastatingly runaway climate; the predations of human beings on ecosystems; an asteroid slamming into Earth; a super-volcano erupting; a thermonuclear conflagration; a global contagion; rogue artificial intelligence; an eventual red-giant sun engulfing us; the pending collision of the Milky Way and Andromeda galaxies. Nor am I talking about the record of short-lived survival of our forerunners, like the Neanderthals, Denisovans, and Homo erectus, all of whom slid into extinction after unimpressive spans.

Rather, I’m speaking of cosmic death!

Cosmic death will occur according to standard physics, including cosmology. Because of the accelerating expansion of the universe and the irrepressibility of entropy — the headlong plunge toward evermore disorder and chaos — eventually no new stars will form, and existing stars will burn out. The universe will become uninhabitable long before its actual demise. Eventually a near vacuum will result. Particles that remain will be so unimaginably distanced from one another that they’ll seldom, if ever, interact. This is the ultimate end of the universe, when entropy reaches its maximum or so-called thermodynamic equilibrium, more descriptively dubbed ‘heat death’. There’s no place to duck; spacefaring won’t make a difference. Nowhere in the universe is immune.

Assuredly, heat death will take trillions of years to happen. However, might anyone imagine that the timeframe veils the true metaphysical significance of universal extinction, including the extinction of humans and all other conscious, intelligent life? And does it really make a difference if it’s tens of years or tens of trillions of years? Don’t the same ontological questions about being still searingly pertain, irrespective of timescale? Furthermore, does it really make a difference if this would be the so-called ‘sixth extinction’, or the thousandth, or the millionth, or the billionth? Again, don’t the same questions still pertain? There remains, amidst all this, the reality of finality. The consequences — the upshot of why this actuality matters to us existentially — stay the same, immune to time.

So, to ask ‘what is the meaning of life?’ — that old chestnut from inquiring minds through the millennia — likely becomes moot and even unanswerable, in the face of surefire universal extinction. As we contemplate the wafer-thin slice of time that makes up our eighty-or-so-year lifespans, the question seems to make a bit of sense. That select, very manageable timeframe puts us into our comfort zone; we can assure ourselves of meaning, to a degree. But the cosmological context of cosmic heat death contemptuously renders the question about life’s purpose without an answer; all bets are off. And, in face of cosmic thermodynamic death, it’s easy to shift to another chestnut: why, in light of all this, is there something rather than nothing? All this while we may justifiably stay in awe of the universe’s size and majesty, yet know the timing and inevitability of our own extinction rests deterministically in its hands.

A more suitable question might be whether we were given, evolutionarily, consciousness and higher-order intelligence for a reason, making it possible for us to reflect on and try to make sense of the universe. And where that ‘reason’ for our being might originate: an ethereal source, something intrinsic to the cosmos itself, or other. It’s possible that the answer is simply that humankind is incidental, consigning issues like beginnings to unimportance or even nonsense. After all, if the universe dies, and is itself therefore arguably incidental, we may be incidental, too. Again, the fact that the timeframe is huge is immaterial to these inquiries. Also immaterial is whether there might, hypothetically, be another, follow-on Big Bang. Whereby the cosmological process restarts, to include a set of natural physical laws, the possible evolution of intelligent life, and, let’s not overlook it, entropy all over again.

We compartmentalise our lives, to make sense of the bits and pieces that competitively and sometimes contradictorily impact us daily. And in the case of cosmic death and the extinction of life — ours and everyone else’s possibly dotting the universe — that event’s speck-like remoteness in distant time and the vastness of space understandably mollifies. This, despite the event’s unavoidability and hard-to-fathom, hard-to-internalise conclusiveness, existential warts and all. To include, one might suppose, the end of history, the end of physics, and the end of metaphysics! This end of everything might challenge claims to any singular specialness of our and other species, all jointly riding our home planets to this peculiar end. 

Perhaps we have no choice, in the meantime, to conduct ourselves in ways that reflect our belief systems and acknowledge the institutional tools (sociological, political, spiritual) used to referee those beliefs. As an everyday priority, we’ll surely continue to convert those beliefs into norms, to improve society and the quality of life in concrete, actionable ways. Those norms and institutions enable us to live an orderly existence — one that our minds can plumb and make rational sense of. Even though that may largely be a salve, it may be our best (realistically, only) default behaviour in contending with daily realities, ranging from the humdrum to the spectacular. We tend to practice what’s called ‘manic defence’, whereby people distract themselves by focusing on things other than what causes their anxiety and discomfort.

The alternative — to capitulate, falling back upon self-indulgent nihilism — is untenable, insupportable, and unsustainable. We are, after all, quite a resilient species. And we live every day with comparatively attainable horizons. There remains, moreover, a richness to our existence, when our existence is considered outside of extraordinary universal timeframes. Accordingly, we go on with our lives with optimism, not dwelling on the fact that something existential will eventually happen — our collective whistling past the graveyard, one might say. We seldom, if ever, factor this universal expiry date into our thinking — understandably so. There would be little to gain, on any practical level, in doing otherwise. Cosmic thermodynamic death, after all, doesn’t concern considerations of morality. Cosmic death is an amoral event, devoid of concerns about its rightness or wrongness. It will happen matter of factly.

Meanwhile, might the only response to cosmic extinction — and with it, our extinction — be for the universe and humanity to shrug?

Monday 6 May 2019

Picture Post #46 A Machine to Peek Into the Universe’s Core



'Because things don’t appear to be the known thing; they aren’t what they seemed to be neither will they become what they might appear to become.'

Posted by Keith Tidman 

The Large Hadron Collider, siad to be the most complex machine ever built by humanity.
Image courtesy of CERN
tale of scale.  The CERN Large Hadron Collider, a Brobdingnagian* machine searching through the Lilliputian world of subatomic particles. This, we are told, to better understand the universe at the smallest scale. The human mind is challenged to take in the machine’s ‘cathedral’ dimensions. I think that the aim of this cathedral, however, is more than just inspiring awe, or reverence, or faith.

Rather, for me this towering monument — testament to human tool-making — has a very different purpose: to pull back the shroud so that humanity can peek into the remarkable inner world of our cosmos, and what it tells us about aspects of reality. Case in point: the confirmation of the Higgs boson a few years ago, whose field gives other particles their mass — ‘convenient’ for a universe like ours, including us.

There’s the hard-core science to all this, to be sure, with international collaboration at its best. But just like more-conventional, faith-based cathedrals, doesn’t this image also inspire humanity to speculate about the cosmology and meaning of this universe that we occupy, our own purpose, and the values we ought to revere? Doesn’t it serve and reward humanity’s instinctual sense of curiosity, imagination, and inspiration — the fertile seedbed of human discovery?



* After the fictional land in Jonathan Swift's 1726 satirical novel Gulliver's Travels occupied by giants

Monday 24 September 2018

Why Is There Something Rather Than Nothing?

For scientists, space is not empty but full of quantum energy
Posted by Keith Tidman

Gottfried Wilhelm Leibniz introduced this inquiry more than three hundred years ago, saying, ‘The first question that should rightly be asked is, “Why is there something rather than nothing?”’ Since then, many philosophers and scientists have likewise pondered this question. Perhaps the most famous restatement of it came in 1929 when the German philosopher, Martin Heidegger, placed it at the heart of his book What Is Metaphysics?: ‘Why are there beings at all, and why not rather nothing?’

Of course, many people around the world turn to a god as a sufficient reason (explanation) for the universe’s existence. Aristotle believed, as did his forerunner Heraclitus, that the world was mutable — everything undergoing perpetual change — which he characterised as movement. He argued that there was a sequence of predecessor causes that led back deep into the past, until reaching an unmoved mover, or Prime Mover (God). An eternal, immaterial, unchanging god exists necessarily, Aristotle believed, itself independent of cause and change.

In the 13th century Saint Thomas Aquinas, a Christian friar, advanced this so-called cosmological view of universal beginnings, likewise perceiving God as the First Cause. Leibniz, in fact, was only proposing something similar, with his Contingency Argument, in the 17th century:

‘The sufficient reason [for the existence of the universe] which needs not further reason must be outside of this series of contingent things and is found in a substance which . . . is a necessary being bearing the reason for its existence within itself. . . .  This final reason for things is called God’ — Leibniz, The Principles of Nature and Grace

However, evoking God as the prime mover or first cause or noncontingent being — arbitrarily, on a priori rather than empirical grounds — does not inescapably make it so. Far from it. The common counterargument maintains that a god correspondingly raises the question that, if a god exists — has a presence — what was its cause? Assuming, that is, that any thing — ‘nothing’ being the sole exception — must have a cause. So we are still left with the question, famously posed by the theoretical physicist Stephen Hawking, ‘What is it that breathes fire into the equations and makes a universe for them to describe?’ To posit the existence of a god does not, as such, get around the ‘hard problem’: why there is a universe at all, not just why our universe is the way it is.



Some go so far as to say that nothingness is unstable, hence again impossible.


 
Science has not fared much better in this challenge. The British mathematician and philosopher Bertrand Russell ended up merely declaring in 1948, ‘I should say that the universe is just there, and that’s all’. A ‘brute fact’, as some have called it. Many scientists have embraced similar sentiments: concluding that ‘something’ was inevitable, and that ‘nothingness’ would be impossible. Some go so far as to say that nothingness is unstable, hence again impossible. But these are difficult positions to support unquestionally, given that, as with many scientific and philosophical predecessors and contemporaries, they do not adequately explain why and how. This was, for example, the outlook of Baruch Spinoza, the 17th-century Dutch philosopher who maintained that the universe (with its innumerable initial conditions and subsequent properties) had to exist. Leaping forward to the 20th century, Albert Einstein, himself an admirer of Spinoza’s philosophy, seemed to concur.

Quantum mechanics poses an interesting illustration of the science debate, informing us that empty space is not really empty — not in any absolute sense, anyway. Even what we might consider the most perfect vacuum is actually filled by churning virtual particles — quantum fluctuations — that almost instantaneously flit in and out of existence. Some theoretical physicists have suggested that this so-called ‘quantum vacuum’ is as close to nothingness as we might get. But quantum fluctuations do not equate to nothingness; they are not some modern-day-science equivalent of the non-contingent Prime Mover discussed above. Rather, no matter however flitting and insubstantial, virtual quantum particles are still something.

It is therefore reasonable to inquire into the necessary origins of these quantum fluctuations — an inquiry that requires us to return to an Aristotelian-like chain of causes upon causes, traceable back in time. The notion of a supposed quantum vacuum still doesn’t get us to what might have garnered something from nothing. Hence, the hypothesis that there has always been something — that the quantum vacuum was the universe’s nursery — peels away as an unsupportable claim. Meanwhile, other scientific hypotheses, such as string theory, bid to take the place of Prime Mover. At the heart of the theory is the hypothesis that the fundamental particles of physics are not really ‘points’ as such but rather differently vibrating energy ‘strings’ existing in many more than the familiar dimensions of space-time. Yet these strings, too, do not get us over the hump of something in place of nothing; strings are still ‘something’, whose origins (causes) would beg to be explained.

In addressing these questions, we are not talking about something emerging from nothing, as nothingness by definition would preclude the initial conditions required for the emergence of a universe. Also, ‘nothingness’ is not the mere absence (or opposite) of something; rather, it is possible to regard ‘nothingness’ as theoretically having been just as possible as ‘something’. In light of such modern-day challenges in both science and philosophy, Lugdwig Wittgenstein was at least partially right in saying, early in the 20th century (Tractatus Logico-Philosophicus, section 6.4 on what he calls ‘the mystical’), that the real mystery was, ‘Not how the world is . . . but that it is’.



Monday 2 January 2017

Picture Post #20 Olber's Paradox raising insoluble questions



'Because things don’t appear to be the known thing; they aren’t what they seemed to be neither will they become what they might appear to become.'


Posted by Martin Cohen and Tessa den Uyl

A NASA  image from the Hubble Telescope looking into the 'Deep Field'
This is a patch of BLACK sky - empty when initially seen - even through the largest earthbound telescopes. Yet, with the  Hubble space telescope and a long-enough exposure time, even the darkness of space soon comes to glowing life. The point is, every bit of sky is actually packed with light - not merely with stars but with uncountable distant galaxies.

Heinrich Olbers (1758–1840) was a Viennese doctor who only did astronomy in his spare time, but realised that there was a bit of a logical problem about the night sky. And ‘O’ is for ‘Olbers Paradox’*,  which can be summed up by saying that if the universe is really infinite in size, the the night sky should not only be bright – but should be infinitely bright. Put short, we should see stars everywhere we look. So why don't we and why isn't the night sky all lit up ?

The paradox touches upon profound issues in cosmology, or the study and theory of the origins of the universe. Simply saying that most of the stars are too far away to see is not enough. Certainly it is true that starlight, like any other kind of light, dims as a function of distance, but at the same time, the number of light sources in the ‘cone of vision’ increases – at exactly the same rate. In fact, on the mathematics of it, given an infinite universe, with galaxies and stars distributed uniformly, the whole night sky should appear to be not black, not speckled, but white!

Olbers’ paradox is a ‘thought experiment’ in the very good sense that most of the reasoning is done by hypotheticals. What if the universe is infinitely large? And infinitely old? If the stars and galaxies are (on average) spread out evenly?

Various possible explanations have been offered to explain the paradox. Such as that stars and galaxies are not distributed randomly, but rather clumped together leaving most of space completely empty. So, for example, there could be a lot of stars, but they hide behind one another. But in fact, observations reveal galaxies and stars to be quite evenly spread out.

What then, if perhaps the universe has only a finite number of stars and galaxies? Yet the number of stars, finite or not, is definitely still large enough to light up the entire sky…

Another idea is that there may be too much dust in space to see the distant stars? This seems tempting, but ignores known facts. Like that the dust would heat up too, and that space would have a much higher. The astronomers who took this image claim it shows some kind of spectral shift into the red specturm. Or is it only the dust? The questions are not really resolved, even yet.

So what is the best answer to Olbers’ riddle? The favoured explanation today is that although the universe may be infinitely large, it is not infinitely old, meaning that the galaxies beyond a certain distance will simply not have had enough time to send their light over to fill our night sky. If the universe is, say, 15 billion years old, then only stars and galaxies less than 15 billion light years away are going to be visible. Add to which, astronomers say that the phenomenon of red shift may mean some galaxies are receding from us so fast that their light has been ‘shifted’ beyond the visible spectrum.

After reading this, and then standing here on planet Earth and watching the night sky, one might feel a little trapped by the questions. Our sight is limited and it always will be but maybe this is our hope for we can continue to philosophise: afte rall, what are we thinking? The picture above might as well represent pieces of coloured glass, under water visions where fluorescent life flows in deep dark sees, a pattern for printed cloth. Our brain only represents what we think we see, not necessarily the reality in which we live? In the incredible immensity of space, mankind has always been aware of this, even if, once in a while, the tendency is to forget.


* Although the paradox carries Olbers’ name,  it can really be traced back to Johannes Kepler in 1610.  In Wittgenstein's Beetle and Other Classic Thought Experiments, Martin’s book, which talks a little more about all this,