Tag Archives: Universe

Why Does the World Exist?: An Existential Detective Story by Jim Holt

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Journalist and former philosophy grad student Jim Holt sets out to answer that long-standing philosophical/scientific question: Why is there something rather than nothing? 

His principal method is to interview a number of well-known philosophers (Adolph Grunbaum, Richard Swinburne, John Leslie and Derek Parfit) and scientists (David Deutsch, Andre Linde, Alex Vilenkin, Steven Weinberg and Roger Penrose). He also talks to John Updike, who is surprisingly knowledgeable about both science and philosophy.

Nowadays, when people ask why the world exists they are generally asking why the Big Bang occurred. Unfortunately, nobody knows. The most common answers are that there was some kind of random quantum event that made it happen or that God made it happen. Some people think that our universe is just a small part of reality and that somehow the existence of a vast, possibly infinite, collection of other universes explains why ours is here and/or why ours is the way it is. The philosopher John Leslie thinks that our universe might exist because it’s good.

As soon as a particular cause or reason for our universe to exist is suggested, it is natural to ask why that cause or reason is the explanation, rather than some other cause or reason. Why are the laws of quantum mechanics in effect? Where did God come from? This is why the answer provided by a Buddhist monk at the very end of the book is my personal favorite: “As a Buddhist, he says, he believes that the universe had no beginning….The Buddhist doctrine of a beginning-less universe makes the most metaphysical sense”.

Perhaps the reality that exists (the super-universe, whatever ultimately caused the Big Bang) has always existed and always will. It simply is. It never came into existence, so no cause, reason or explanation is necessary or possible. Perhaps it’s cyclical. Perhaps it’s not. But it’s eternal, with no beginning or end.

This book is worth reading, but not as good as it might have been. Mr. Holt writes well and seems to accurately present the ideas of the thinkers he interviews. But his own thoughts on the subject, and other subjects, such as consciousness and death, aren’t especially interesting or profound. In particular, his attempt to prove the existence of an infinite yet mediocre universe is completely unconvincing. His travel writing — where he stayed, what he ate, his strolls through Oxford and Paris — is also a bit much. He doesn’t just bump into a philosophy professor at a local grocery store; it’s a “gourmet” grocery store. He has excellent taste in food and drink as well.  (9/8/12)

Worlds Upon Worlds, According to David Lewis

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David Lewis, who spent most of his career at Princeton, was one of the most respected  philosophers of the 20th century. Yet he is most famous for advocating a philosophical view that almost everyone else rejects.

In his 1986 book On the Plurality of Worlds, Lewis argued for a position he called “modal realism”. This is the idea that there are an infinite number of possible worlds (i.e. self-contained universes) different from our own, and that all of these possible worlds are as real as the world we live in. The only fact that sets our world apart from the rest of them is that it is ours.

Saying, therefore, that our world is the “actual” world is no different from saying that I am “here” and the time is “now”. There are people just like us and as real as you and me existing in other worlds who believe that their world is the only “actual” world. They are just as correct in their belief as we are in ours.

Most philosophers are comfortable with talking about possible worlds. They use this terminology to explain, for example, the nature of necessity and what it means to say that something could have happened but didn’t. A statement is necessarily true if it is true in every possible world. An event could have happened if it happened in some possible world, especially one similar to our own. Yet philosophers almost all deny that other possible worlds are as concretely real as this one.

Lewis knew, of course, that modal realism is very hard to accept. It clearly conflicts with common sense and ordinary language. He described the natural response to his position as the “incredulous stare” (as in “You can’t be serious, Professor Lewis!”). But he argued that there are excellent theoretical reasons for accepting modal realism. He thought that it best explains what it is to be a possible world.

It takes some education and intelligence to appreciate Lewis’s reasons for adopting modal realism and his arguments against competing views. Personally, I’m tempted to say that modal realism is self-contradictory. To claim that possible worlds exist in the same way that the actual world exists sounds like a contradiction in terms. (Which might explain why Lewis found modal realism to be such a useful view. Logic says that if you start with a contradiction, you can prove anything at all.)  

On the other hand, many physicists believe that there are a multitude of universes, completely separate from each other, yet equally real. That might seem to be what Lewis had in mind, but it’s really not. For philosophers, there is a possible world for each possibility, every single one (although only one of them, contra Lewis, is real). For physicists, there might be many, many real worlds, just as real as ours, but they don’t reflect every single possibility. They are merely the result of whatever natural processes result in the creation of new universes.

In the philosophical sense, therefore, there is a possible world in which donkeys do calculus, since very bright donkeys could conceivably do that. Physicists don’t go that far, since there is no reason to believe that animals like donkeys (no offense, donkeys) would ever develop an interest in advanced mathematics.

 http://en.wikipedia.org/wiki/Modal_realism

http://plato.stanford.edu/entries/david-lewis/#6

Isn’t One of the Damn Things Enough?

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Theoretical physicists talk about parallel or multiple universes a lot these days. The interesting video below explains that there are three main kinds of theories under discussion.

My favorite version is #1. It’s the kind of scenario described by the physicist Lee Smolin in a wonderful book called The Life of the Cosmos. Smolin suggested that we live in a universe that is fit for life (molecules stick together, for example) because a black hole in universe X will tend to generate a new universe Y that is similar to universe X, but not exactly the same (like parents have offspring who are similar but not the same). So there tend to be universes that are like the one we happen to live in, with lots of black holes and natural laws compatible with life. Cosmology meets the theory of evolution and explains why our universe is such a nice place to hang out.


If you’re interested, check out other videos on Henry Reich’s MinutePhysics channel:

http://www.youtube.com/user/minutephysics/videos?view=0

Why Is There Something Rather Than Nothing?

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There is a new book out by journalist and former philosophy grad student Jim Holt called Why Does the World Exist? It’s worth reading if you’re interested in questions like that.

Nowadays, when people ask why the world exists they are generally asking why the Big Bang occurred. Unfortunately, nobody knows. The most common answers are that either some random quantum event or some higher being made it happen. Some physicists think that our universe is just a small part of reality and that the existence of a vast, possibly infinite, collection of other universes explains why ours is here and/or why ours is the way it is. 

As soon as a particular cause or reason for our universe to exist is suggested, however, it is natural to ask why that cause or reason is the explanation, rather than some other cause or reason. Why are the laws of quantum mechanics in effect? Where did God come from? Where did all those other universes come from?

This is why the answer provided by a Buddhist monk at the very end of the Why Does the World Exist? is my personal favorite: “As a Buddhist, … he believes that the universe had no beginning….The Buddhist doctrine of a beginning-less universe makes the most metaphysical sense….A billion causes could not make the universe come into existence out of what does not exist”.

Perhaps the reality that exists beyond our universe or that preceded the Big Bang (the super-universe, the multiverse, the quantum foam, whatever it might be) always existed and always will. It simply was. Or is. It never came into existence, so no cause, reason or explanation is necessary or even possible. Perhaps it’s cyclical. Perhaps it’s not. Perhaps it’s always changing. Perhaps it isn’t. But it had no beginning and might have no end.

The great 17th century philosopher Spinoza referred to all of existence as “God, or Nature” (Deus, sive Natura): “That eternal and infinite being we call God, or Nature”. I prefer “Nature” to “God”. To Spinoza, it was the same thing and it was eternal.