on 9 December 2014
A very interesting read, plugging an important gap in popular science books, and well worth the price.
The reason I wouldn't give it 5 stars is because I think some of concepts could have been better explained, and I had a lot of questions firing in my head as I read the book, which weren't answered. If you read a book by Richard Dawkins, he explains everything in almost too much detail (and I find myself thinking 'yeah, yeah, I got it' and skipping ahead) - in this book it's the opposite.
Perhaps I'm being a bit harsh in that our brains have not evolved to be able to visualize quantum mechanics, and it can only really be understood by the mathematics - the level of which is beyond the majority of the population.
In this book, Lawrence Krauss addresses the problem of how the complex universe we observe arose out of `nothing'. In the Preface he briefly discusses the different meanings ascribed to this word by scientists, philosophers and theologians. Not surprisingly, there is little progress to be made here. Better to leave the philosophers and theologians to their word games and concentrate on the job of exploring its consequences in nature. That is what is done in this book.
Krauss starts with the standard history of the Big Bang: the evidence that supports it, and the need to introduce `dark matter' to reconcile measurements of galactic dynamics with the observed mass of their constituents. Dark matter is about 30% of the energy of the universe. Its nature is still unknown and is a very active field of research in particle physics. Then came the speculation that quantum fluctuations result indirectly in `empty space' being the source of an even greater energy, the so-called `dark energy', which would be about 70% of the total energy of the universe. The amount of mass/energy in the universe determines its geometry, and experiments in 1998 confirmed a `flat' universe (the meaning of this term is carefully explained) so the existence of dark energy is now inescapable. It implies a resulting force that causes the expansion of the universe to increase, rather than to decrease, as had been assumed. The origin and nature of dark energy is the greatest unsolved puzzle in physics today.
Krauss then considers how quantum fluctuations could have produced the conditions for a flat universe, since even a minute deviation from flatness at the time of the Big Bang would not produce the flat universe we see today. The answer is `inflation', the idea that the universe could have experienced a super-rapid expansion for a very short time after the Big Bang, the only viable explanation of the observed flatness and extreme homogeneity of the universe. He also explains how inflation `freezes' these fluctuations, which later emerge as the minute matter inhomogeneity that has been observed by experiments like WMAP and which later, under the influence of gravity, led to the formation of galaxies, stars and eventually us. Hence the title of the book.
The most startling consequence of living in a flat universe is that as it continues to expand, galaxies will eventually have velocities that exceed the velocity of light (the velocity is that of the expansion of space, not particles travelling through space, so no problems with special relativity) and will no longer be visible from any other galaxy. Paradoxically, this means that any future astronomers will not longer have the evidence to deduce that they are part of an expanding universe and so `starting from scratch' they could well come to an entirely different conclusion. Krauss gives a very interesting discussion of the extraordinary fact that we live in a relatively short time window (in terms of cosmological time) where it is possible to make the deductions we have about the universe, because `now' is the only time when the energy in empty space is comparable to the energy density in matter. Had the dark energy been even only 50 times bigger than at present, galaxies would not have formed and we would not exist. This leads on the ideas of multiple universes and the anthropic principle, which is the cause of so much controversy in physics today. Along the way he cannot resist gently prodding string theories and `theories of everything' (or `theories of anything' as he calls them).
The known scientific story essentially ends here, but the book continues with three more chapters. The first returns to the `something from nothing' question and essentially re-emphasizes how our knowledge of the universe has been obtained purely from the laws of physics and without the need for divine intervention. The second explores how a quantum theory of gravity might, via quantum fluctuations, produce a stable universe, with matter and radiation, from a `nothing' that did not include even space itself, and that such a universe would necessarily be flat, just as our own universe. This is highly speculative and the matter-antimatter asymmetry problem is far from solved. The last chapter tackles head-on the argument that there still needs to be a deity to determine the laws of physics - a First Cause. Here he discusses even more speculative ideas that imply universes can arise without the necessity of the laws of physics, the latter being random. His conclusion is that theology and philosophy are incapable of answering fundamental questions and that only by using the scientific method can we let nature tell us its secrets: `God is either unnecessary, or at best redundant'.
This book gives a very clear discussion of some of the most exciting ideas in cosmology today, and gives a real feeling for what enormous strides have been made in understanding the origins of the universe, as well as the unanswered questions. But the discussion is necessarily sometimes quite technical, with terms and concepts introduced without much explanation. This could mean a steep learning curve for someone without at least some previous acquaintance with the material, although there is an excellent index to enable one to navigate around the book. The poor quality of the illustrations does not help. Some of these would have been more impressive and easier to understand had they been in colour. Given the high price of £17.99 for a book of less than 190 pages (published by the ironically named Free Press), surely this could have been possible. Despite these minor reservations, this is a superb book.
on 29 July 2012
The particle physicist and cosmologist author is an engaging popular science writer. The author addresses the general reader who has an interest in cosmology while the text does not contain a single mathematical formula. The author takes us into a fascinating journey during which he weaves the arguments that led astrophysicists and cosmologists to develop a compelling scenario of a universe being created from virtually nothing, precisely dating its creation at 12.72 billion years ago.
The author wisely advises the reader quoting Jacob Bronowski that the nature of the universe will not be the result of hope, revelation, or pure thought;it will emanate from probing its nature and we have to accept it as it is whether we like it or not and even when it runs counter to our intuition or defies our imagination.
I find it productive to commence the review proper by defining what the author means by the term 'nothing' because in science even 'nothing' has to be defined. In the context of the book it means empty space with energy associated with it, even in the absence of any matter or radiation and in which the laws of nature such as quantum mechanics and general relativity operate. In this sense empty space is complicated. It is teeming with virtual particles that pop in and out of existence in a time so brief we cannot see them directly. Virtual particles are manifestations of a basic property of quantum systems. These 'quantum fluctuations' imply something about the quantum world:nothing always produces something, if only for an instant;or as cosmologist and Nobel prize laureate, Frank Wilczek aptly put it 'nothing' is unstable.
We can outline the scenario of creation as follows:we can speculate that the universe began in the most symmetrical state possible and that in such a state no matter existed;the universe was a vacuum. A second state existed, and in it matter existed. The second state had slightly less symmetry, but was also lower in energy. Eventually a patch of less symmetrical state appeared and as visualized by astrophysicist Alan Guth and permitted by general relativity inflated or expanded exponentially (the Big Bang) so even the tiniest region at early times could could quickly encompass a size more than large enough to contain our whole universe today. In fact we have a notion for both the enormity of the expansion and the corresponding time frame:it took a fraction of a second to go through twenty-eight orders of magnitude. According to this picture, when inflation ends, the energy stored in empty space gets turned into an energy of real matter and radiation, creating effectively the traceable beginning of our Big Bang expansion. We say traceable beginning because inflation effectively erases any memory of the sate of the universe before it began.
There are three main observational pillars that led to the empirical validation of the Big Bang:the observed Hubble expansion (as evidenced by the red-shifted radiation from distant galaxies);the observation of the cosmic background radiation (the afterglow of the Big Bang);and the observed agreement between the abundance of light elements - hydrogen, helium, and lithium - we have measured with the amounts predicted to have been produced during the first few minutes of the history of the universe.
We have already noted that the slight asymmetry between matter and antimatter led to the creation of the universe. If matter and antimatter were exactly equal they would have mutually annihilated with radiation as the only result. Even if the asymmetry were 1 part in a billion there would be enough matter left over to account for everything we see in the universe today. In fact an asymmetry of 1 part in a billion or so is precisely what was called for, because there are roughly 1 billion photons in the cosmic microwave background radiation for every proton in the universe.
A word might be in order on the mass composition of the universe. It might come as a surprise to many that the visible universe that is galaxies, stars, planets, and cosmologists who speculate about the nature of the universe comprise a mere 1 percent of its mass while adding dark matter in and around galaxies still amounts to 30 percent of the universe mass;a commanding 70 percent of its mass belongs to a mysterious dark energy which permeates uniformly empty space, is believed to have remained constant through time while it bears an uncanny resemblance to Einstein's cosmological constant.
I find it appropriate to conclude the review by convincing the skeptical reader of the reality of virtual particles. We have mentioned earlier in the review that virtual particles pop in and out of existence in a time so short we cannot see them directly. But how can we be sure they are real? The answer is through their effects and the validation follows:physicists can use Dirac's equation to calculate to an amazing high precision , the impact on the spectrum of hydrogen of all possible virtual particles that may exist intermittently in the vicinity. And when we do, we come up with the best, most accurate prediction in all of science. Using Dirac's equation, and the predicted existence of virtual particles, we can calculate the value of atomic parameters and compare them with observation and obtain an amazing agreement of about 1 part in a billion or better! The evidence for the existence of virtual particles is incontrovertible.
I leave the reader in suspense to find for himself the frightening fate of our universe in the distant future, say two trillion years from now.
Why is there something rather than nothing? What do we even mean when we talk of nothing?
In this book, the author, expanding on his popular YouTube video, describes how developments in cosmology over the last 20 years or so have helped further our understanding of the origin of our universe as well as where it is likely to be heading and how "something" may indeed have come from "nothing". We may, as the author points out, also be extremely fortunate to be living in what is a (cosmologically speaking) brief window in the history of the universe in which the evidence for the origin of the universe is relatively easily observed and deduced.
Generally speaking, I found this to be as well-written and lucid account of our current understanding of our universe, its origins and future as any that I've come across. While the author in the main does a good job of getting across some complex ideas it isn't always an easy read and is tough going in places. I found myself on several occasions thinking "No. Don't get that!" and heading back to the start of that particular passage. It is worth sticking with though and does reward the patient reader, as I can testify!!
on 23 December 2015
Physics has three cornerstone theories -- the standard model of particle physics and quantum mechanics, which describes particles and fields at small scales; general relativity, which describes space and time at large scales; and thermodynamics, which gives an arrow to time. These describe in exquisite accuracy how the world works, except at very high energies, small times or distances.
There are candidate theories such as inflation, string theory, or quantum loop gravity, for these high-energy small-time cases, but none has been verified to anything like the extent as the cornerstone theories, if at all. For example, they seem to occur, if at all, at much higher energies than we can produce in the lab. Moreover, each is not so much a theory as a collection of loosely related rival theories.
In this book, Dr Krauss shows how his flavour of inflation theory explains how nothing (in his definition of the word) spontaneously decays into a universe, or indeed many universes. He believes that this explains the old philosophical problem -- “why is there something rather than nothing?”
From a physics perspective, I am confused by any theory that talks about ‘before’ the big bang, or of an external cause of the big bang, since big bang theory itself says that both time and space begin at the big bang. Indeed, some multiverse theories say that some of the universes will have multiple time dimensions. Where is the time or the location for the nothing of Krauss’s initial state to decay from, if there is no time or space? (read about the Hartle-Hawking state, for example.)
From a theological/philosophical perspective, I am far from convinced that Dr Krauss’s poorly defined physical idea of ‘nothing’ maps to anything that philosophers would be interested in. If it is somehow a prior state, such as some special unstable form of ‘nothing’, then where did that state come from? If it is not a prior state, then really what he is saying is standard big bang theory, that questions about ‘before’ the big bang are not part of physics.
Not that theologians should take comfort. A gap in physics is not evidence for the existence of God, and particularly not the existence of a personal god who listens to prayers or cares about humans. Moreover, I am optimistic that some of these gaps will be closed. There is evidence hidden in the background radiation which may point to some theory of origin of the universe, possibly some variant of inflation theory.
So, contentious physics and poor philosophy, but nonetheless an interesting read -- accessible to those without a physics background, and a well-presented summary of inflation theory.
on 8 May 2013
If I have got this right, it all depends on accepting that what we used to accept as empty space or nothingness is in fact a heaving mass of energy which produces at quantum level mysterious particles which blink in and out of existence, and which change their behaviour if observed. Whether that is regarded as a satisfactory explanation of the book's title - Krauss indeed insists that something has to come from nothing - will depend on the viewpoint of the individual reader. Krauss makes rather a lot of the fact that this purely scientific explanation eliminates the need to see God or a supreme creator as being responsible for the universe, and follows this up by unleashing Richard Dawkins to write a somewhat triumphal afterword, which some people may find offputting. The book is written in clear and largely jargon-free language, but the difficulty is that the concepts under discussion are so contrary to accepted logic that I found that the explanations can require multiple readings to grasp what point is being made. One can understand the individual words, but what they add up to requires work, and not everyone will think the effort is worthwhile, although its far more accessible than Hawking's Brief History of Time.. Overall, however, a fascinating introduction to modern thought on a fundamental scientific debate. Irrespective of whether one takes on board the arguments Krauss puts forward, it arguably does no harm to give the brain a workout like this from time to time.
This was a difficult book. Not on account of its style - it's well written and I never lost interest throughout - but on account my difficulty in comprehending some of the radically counter intuitive ideas presented therein. Whether other readers suffer from the same handicaps as I did will depend on their degree of expertise in this subject or whether they are better capable than I am of grasping the ideas in this book.
Let me tell you from a lay perspective what I did manage to grasp. The book goes over some familiar ground, the nature of the universe has cosmology has revealed to us over the past 100 years - how we can tell that the universe is as old as it is and the by now familiar problem of dark energy and matter. The fact that the atoms in your body were forged countless millennia ago in the nuclear furnaces of long dead stars and other such wonders are covered well. He also offers a fascinating prognosis on the universe's eventual fate - now is a great time to be a cosmologist, because in a 100 Billion years time, space will expand so fast that it will physically haul galaxies along with it faster than the speed of light. That means we will no longer be able to observe other galaxies and our galaxy will appear to be alone in the universe.
But what does Krauss mean by nothing? Well, he seems to be using it in two senses. The first is empty space. It is not in fact empty. What we think is empty space is in fact mass, it has energy, it produces particles which seemingly spring from nowhere and disappear back into nowhere. Nothing in empty space weighs something because of quantum effects - particles constantly bubbling up from seemingly nowhere. That goes for sub atomic level too, 90 percent of a mass of a proton is empty space! And of course you're atoms are made from protons. That means much of your mass is empty space! Can you test this? Apparently so - you can actually weigh the universe and all the matter in it, visible and invisible.
But what about a universe from nothing, the second sense of the word, the time before there were was anything in the universe - galaxies, planets, stars and astronomers to observe them? The answer is this: the attractive effects of gravity cancel out expansive energy generated by visible and invisible matter. The two forces cancel each other out and produce a zero - this is the `number' of the universe. This allows a universe to spring from nothing. No deity required. Why is there something from nothing then? Well it has to be, quantum mechanics will always give something out of nothing. This is something that as a layman I find fantastical but the fact that it's strange should not be reason for me or any layperson to dismiss this out of hand. Science is full of strange things. Gravity and electromagnetism are real forces but neither can be smelt, seen, heard or tasted. But they exist and they have real effects. They can be detected and their forces harnessed. It seems mind-boggling but science does not come naturally to us. It is by its nature counter-intuitive.
What does this mean for those who believe in a creator deity? Can you still say that god laid down the laws of physics? In principle you can say this and this book is not the last word on this question. But science shows that the laws of physics can give rise to things like clouds and rainbows without any need for a creator to intervene. Ditto with the universe generally. Stars are being born and die all the time without any creator lighting the blue touch paper. And particles can bubble out of nowhere without a god bringing them forth. The laws of physics allow this. But a creator that merely wound the universe up like clockwork and simply let it get on with itself is probably not the sort of deity that many devotees of the monotheistic religions would consider worthy of worship. Such a god has foresaken his creation - one that is doomed to die a heat death in the very long run. Science will doubtless change the way we look at the universe but one thing it won't do is allow a god who can actually intervene and override the laws of nature.
There will of course still be mystery. But, as Krauss has said elsewhere, science specifies what uncertainly is - unlike religious dogma that asserts to know the nature of reality without bothering to check it out first. Still, while there is mystery, there is always the possibility of appealing to mystery, to posit a god of the gaps. However inadequate this argument is, it is always an option - if a somewhat desperate one - as long as mystery exists. So this book won't herald the final overthrow of organised religion but it won't offer any crumbs of comfort, either.
Despite being a difficult book, one that needs to be read and re-read, this is a fascinating portrait of the nature of scientific discovery and advance, concerning the question of why the universe is the way it is.
on 31 May 2015
An interesting perspective on the probable 'shape', substance and expansion of the known and theoretical Universe(s). Should be read alongside other literature on the subject as it is at times; quite a biased view (flat Universe, String Theory etc.). As with most books of this ilk, the more simple concepts are reiterated and those more difficult to grasp are given only circumspect attention and explanation. One question I have for authors of such books: why do you ever insist on mentioning God as part of your reasoning? The sooner you drop the notion of a deity being in any way relevant to the PHYSICAL laws and processes that govern the Universe (however poorly understood to-date), the sooner we can assign such topics to the fiction sections in our Libraries. I sincerely hope that one day, the majority of human society, when remarking on the notion of a deity having an influential effect will say "Oh yes, that's what people used to believe,"
on 5 December 2015
This is a frst class description of current thinking in Cosmology. The author's writing style enables the non-specialist to grasp the fundamental problems without being totally overwhelmed. It was good to see references to Henrietta Swan Leavitt and Vera Rubin as contributions made by women are often over-looked. It was news to me that fields created by virtual particles provide the bulk of the mass of protons and neutrons. As a bonus this book helped me to reconcile something that had bothered me for sometime. Nothing can travel through space faster than the speed of light (Einstein's Special Relativity Theory) while space itself can exceed the speed of light (Alan Guth's Inflation period that followed the "Big Bang".) It seems we are living in a flat universe where the energy of empty space (Dark Energy) accounts for 70% of the total energy with energy in matter acounting for the remaining 30%.
on 7 July 2014
I found it quite confusing at times, but the book does talk about some difficult subjects. There are some great statements in there that make it worth while though. It wet my appetite for more of the same, and the same author too!
I do recommend it even if its not such a simple read.