Customer Reviews

Godel Meets Einstein : Time Travel in the Godel Universe

5 star:		(2)
4 star:		(2)
3 star:		(0)
2 star:		(0)
1 star:		(1)

 

 

This absolutely riveting book delivers at two levels: first, it can serve for any intelligent reader as an exhilirating introduction to most of the central questions of philosophy--questions concerning time, truth, death, thought, free will, and infinity, to mention just some of the ground covered. Second (and this is what makes it such an astonishing book) it offers, in the context of its luminously clear and helpful discussions of these issues, a series of original and profound philosophical results. Many of these insights in effect open a new chapter in the domains they deal with (see, for example, Yourgrau's powerfully argued rejection of the standard way of understanding both existence (represented in logic these days by the 'existential quantifer') and infinity (esp., the sum of an infinite convergent series). In reading the book you are given a front row seat onto all of this--some of the newest, most surprising, and most fundamental work in philosophy. Those coming to the book from physics (i.e. the 'Einstein' end of things) will, I suspect, be refreshed by the idea of a harmonious and fruitful relationship between philosophy and science that infuses the book (after all, Einstein and Godel talked philosophy AND physics). In short, an extraordinary book not to be missed.

Although ostensibly this book is about Godel's solutions to Einstein's General Theory of Relativity and his consequent view of time, it is in fact broader than that. This could be instead considered a book on the philosophy of time with consideration of the GTR and using Godel's views on time and the GTR as a common thread.

As such, it is a difficult read. It will require of someone a fairly strong comprehension of philosophy and metaphysics, as well as (at least) a conceptual grasp of GTR, formal logic and Godel's Incompleteness Theorem, and some understanding of Cantor's transfinite numbers.

The philosophical references run from Plato and Aristotle to Kant and McTaggart. It is wide-ranging in it's coverage of differing views and how they relate to Godel's own views on time. Topics such as "The Epistemology of Potential Infinity" and "Frege and the Decontextualization of Thought" are representative of the depth of this book. Discussions of potential vs. actual infinities, truth in relation to time, the ontology of space-time diagrams, and so on, can leave one reeling.

In addition, comparisons between Godel's Incompleteness Theorem and his approach to his solutions to GTR are made, in hopes of elucidating Godel's ingenuity in finding unexpected solutions to various formalisms.

So, this book really attempts to go far beyond it's title. I think it generally succeeds, however, I find some of the organization of the book annoying, and I wish it were layed out differently. (However, in fairness, if it were my task I have no idea how I would go about reorganizing such complex material - it just seems that it could be done). The book is very heavily referenced (sometimes excessively it seems), and practically every page has at least two or three quotes. I think this tends to make the overall flow of writing less than natural, but it is a matter of style.

Finally, the appendix on Zeno's paradoxes is, to me, very well done and worth half the price of the book right there. Yourgrau clarifies in particular the issue of limits vs infinite sums, and all-in-all provides compelling reasons for claiming that Zeno's paradoxes remain unsolved despite some claims to the contrary.

This is a difficult philosophy book, but there are a number of interesting ideas worth thinking about for those who are interested in the philosophy of time, specifically in what physics seems to tell us about the nature of time. This book is actually an expanded edition of Yourgrau's (1991) book, The Disappearance of Time. I think it's a bit disingenuous to issue what is pretty much the same book under a new title. Godel Meets Einstein has one new chapter (definitely worth reading) and two new appendicies.

This book is incredible. I am reading it twice over. That's how great a book I think it is. What I find so intriguing about it is that the author, Palle Yourgrau, writes a very scholarly exposition about how Godel viewed time to be ideal rather than real against the backdrop of Einstein's concept of the universe as a four dimensional manifold. It really brings to light what the great genius, Einstein, thought about time and whether time travel is possible in the Godel universe.

This is a truly appalling book. If you decide to base your knowledge of relativity, time, Godel or Godel's work on this book then you justly will be humiliated by the first person who has even a passing grasp of the issue.

Firstly, it is clear that Yourgrau doesn't understand Godel's famous theorems. Whilst patronizing the reader about how it is OK not to understand this theorem he shows his own shallow grasp. Godel's theorem essentially says in any mathematical system there are infinitely more statements that cannot be "decided" as to whether they are true or false based on the axioms. In fact if you pick a statement at random is has a probability zero of being decidable. So as for it showing that somehow computers cannot prove things that humans can, well clearly this claim is false.

Secondly there are glaring historical errors. The people who invented the mathematical basis for computers are Turing, Church and Von Neuman. Godel did not invent recursive functions, Church did. We have discussions on people who were proven wrong about the nature of space and time literally hundreds of years ago - Kant and his assertions that space must a priori only be Euclidean and 3 dimensional was being proven wrong even as he wrote. Only a philosopher would bring him up today.

Then finally we get to the nub of Yourgrau's claims. Godel came up with a very specific solution that has closed worldlines. What does this mean? It means that that if you follow any particles path long enough it comes back to the same point - ie same spot in space and crucially also in time. So A isn't "before" B and B isn't "before" A. Surely this means that there is no time? No it doesn't, it means that rather than a worldline being like the line it is like a circle. But surely it means that causality is violated because A cannot cause B if it is not before B! No, it is a universe that is Acausal, ie there are no causes which is not the same as being non-causal - which is when causality is violated. But maybe this could have a relevence to our universe? Well no, because we KNOW - and have done for over 50 years - that OUR universe is expanding which is not allowed in Godel's solution. This is the REAL reason Godel's solution has been ignored because it falls at the first test when compared with the real world. Apparently ignorant of this fact, Yourgrau attempts to use "analogy" to show "relevence", that the differences are "accidental" - they aren't but never mind - and so Godel's solution "could" be relevent. Well that sort of illogical, ignorant pseudo-argument make cut the mustard in Philosophy but it is laughable in Maths and Physics.

In short one of the worst popular science books around. If you buy this book then it will give some him money to carry on writing, so do yourself - and the general public - a favour; buy Goldstein's "Incompleteness" and Simon Singh's "Big Bang" and learn from people who have bothered to have at least a passing grasp of their topic. I wish I could give it no stars.