The Statistical Universe
A direct link to the above video is at http://www.youtube.com/watch?v=UzDfIRMeOkY
In entries like The Map and the Territory, The Long Undulating Snake, Suffering in the Multiverse, Does the Multiverse Really Exist? and Nassim Haramein, I've talked about the idea proposed by physicists that there are actually ten to the power of 500 other universes with different basic physical laws from the universe we find ourselves within. Coincidentally, I just posted the video version of the Nassim Haramein blog to youtube a few days ago, take a look:
A direct link to the above video is at http://www.youtube.com/watch?v=4OZj1XAjcTY
Last October, Seed Magazine published a great article written by one of the two physicists who came up with that proposed number of ten to the power of 500 possible universes. Raphael Bousso is a theoretical physicist at The University of California, Berkeley. His article was called The Statistical Universe: please do check out the whole article. Here's a few paragraphs:
We cannot see farther into the universe because the big bang happened only 14 billion years ago and light from distant regions has not had enough time to reach Earth. Yet subtle clues are beginning to reveal some of the properties of the regions of space hidden beyond our cosmic horizon. Our world appears to be only a small part of a “multiverse,” an expanse vastly larger than the visible universe, and for the most part completely different from it.
The multiverse comprises a large number of distinct patches, each far bigger than our night sky. What observers see, therefore, also depends on where they find themselves. Most of the regions in the multiverse are inhospitable to life, and their properties will not be observed. But what exactly is life? In order to extract predictions from the multiverse, my colleagues and I have developed a statistical tool to find regions with observers: We look not for life itself but for the disorder left behind by the complex processes that its formation depends on. To understand the physical signatures of life in this way may help us finally to comprehend our own little corner of the multiverse.String theory is the leading candidate for reconciling two very fundamental laws — gravity and quantum mechanics. But to accomplish this feat requires at least nine dimensions of space, when we see only three. In order for six dimensions to have remained undetected, they must be tied up into loops too small to see under our best microscopes. In physics there are fundamental laws and local laws, which depend on the environment. Iron and carbon are made from the same elementary particles but assembled differently. As a result local properties like density and conductivity differ widely. The fundamental laws of string theory also appear as different local laws, depending on how the extra dimensions are tied up. If we could open the knots and tie them differently, then supposedly “fundamental” phenomena, like neutrons or the electric force, would disappear and be replaced by an utterly different set of particles and forces.
Because extra dimensions need not be tied up the same way everywhere, physical laws may vary from place to place. Inflation makes each “legal district” much larger than the visible universe, giving us the illusion that particles and forces are the same everywhere. But beyond our cosmic horizon, inflation allows the universe to grow so enormous that it contains every set of possible laws that can be constructed from string theory. Eight years ago, Joe Polchinski and I estimated that the number of possibilities is truly enormous: a one with roughly 500 zeros behind it (10500).
Let's pause and point out the similarities between what Dr. Bousso is talking about and my approach to visualizing the dimensions. First of all, he states that there is a spacetime horizon to our universe, extending back almost 14 billion years, but the multiverse of other different-initial conditions universes lies beyond that horizon. In The Holographic Universe, I showed an animation visualizing how this is much like what happens when you're in the middle of the ocean - you see a horizon which is the same distance away no matter which direction you look, but there is still a much larger sphere beyond that horizon. Transferring that idea to 4D spacetime rather than 3D space is a mind-boggler, and I have been continuing to insist that this all makes more sense if you imagine that this 4D "spacetime horizon" shows how spacetime has a very slight curve to it. That curve moves through the fifth dimension (where Kaluza demonstrated to Einstein that the field equations for gravity and light are resolved), and the idea that our spacetime is a projection from a 5D hologram ties nicely to all this.
Next, he talks about the idea that many parts of the multiverse will be inhospitable and chaotic jumbles, but there will also be regions somewhat like our own where matter and energy are stable enough to allow some other kind of life to form. Since the basic physical laws of a universe within this other part of the multiverse would be different from our own, the life that arises there would almost certainly be very different from what we think of as life as well. We've talked about this idea recently in blog entries like Alien Mathematics and The Flexi-Laws of Physics, and we've looked at some scientific theories that take the "observer participation" idea to a logical extreme in The Biocentric Universe and The Biocentric Universe Part 2.
Thinking of this multiverse of universes as a probabilistic set of possible arrangements that lie outside of our spacetime has led me to talk about the concept of there being a "probability space" for the information that becomes our reality. I've talked about this in blogs like You Have a Shape and a Trajectory, Time in 3 Dimensions, Information Equals Reality, and The Fifth Dimension Isn't Magic. One question that is sometimes asked is why do we even need to imagine that there is a multiverse of other possible universes? Dr. Bousso offers a succinct explanation:
Here's a great video from the TED Talks series featuring astrophysicist George Smoot talking about the structure of spacetime. Dr. Smoot won the 2006 Nobel Prize in physics (along with John Mather) and is a physicist at the University of California at Berkeley. There are some really stunning graphs and animations in this presentation, please do try to watch all 19 minutes. I'm impressed with how Dr. Smoot does such a good job of walking the same line I try to: if our universe sprang from a selection pattern that established some basic rules, some basic laws, and the universe sprang from all that, then what you call the selection pattern doesn't matter. In God 2.0 I talked about the well-known debunker and publisher of Skeptic Magazine, Michael Shermer, who (somewhat surprisingly) says he is quite willing to accept the argument for the existence of a selection pattern that some people call God when it is expressed in these terms.
A direct link to the above video is at http://www.youtube.com/watch?v=c64Aia4XE1Y
I particularly liked the animation Dr. Smoot shows from about the 10:55 mark, because it visually ties so nicely to what we talked about in Nassim Haramein: there's a fractal, recursive, self-similar nature to the structures of our reality, and people who compare images such as those seen in this animation to pictures of the human brain's neural pathways do seem to be on to something very interesting.
If our incredibly fine-tuned universe that allows for the unlikely miracle of our existence is just one out of 10500 possible universes, then statistically speaking we have all hit the most unlikely jackpot imaginable just by virtue of our own existence. A few entries ago, in Poll 44 - The Biocentric Universe Theory, I mentioned the idea that we have new proof that life is a process which exists outside of spacetime. We'll tie these two ideas together next time in "Beer and Miracles".
Enjoy the journey!
Rob Bryanton
Other related entries:
Unlikely Events and Timelessness
Randomness and the Missing 96%
Elvis and the Electrons
"t" Equals Zero
The Big Bang is an Illusion
The Flexi-Laws of Physics
An Expanding 4D Sphere
Next, he talks about the idea that many parts of the multiverse will be inhospitable and chaotic jumbles, but there will also be regions somewhat like our own where matter and energy are stable enough to allow some other kind of life to form. Since the basic physical laws of a universe within this other part of the multiverse would be different from our own, the life that arises there would almost certainly be very different from what we think of as life as well. We've talked about this idea recently in blog entries like Alien Mathematics and The Flexi-Laws of Physics, and we've looked at some scientific theories that take the "observer participation" idea to a logical extreme in The Biocentric Universe and The Biocentric Universe Part 2.
Thinking of this multiverse of universes as a probabilistic set of possible arrangements that lie outside of our spacetime has led me to talk about the concept of there being a "probability space" for the information that becomes our reality. I've talked about this in blogs like You Have a Shape and a Trajectory, Time in 3 Dimensions, Information Equals Reality, and The Fifth Dimension Isn't Magic. One question that is sometimes asked is why do we even need to imagine that there is a multiverse of other possible universes? Dr. Bousso offers a succinct explanation:
This may seem laughable, but without the multiverse our finest theories predict that empty space should contain about 10123 times more energy than it actually does. This is known as the “cosmological constant” or “dark energy” problem. It has been called the “worst prediction in the history of science” and the “mother of all physics problems.” And it was the main reason why Polchinski and I, building on work of Steven Weinberg and others, began studying the multiverse of string theory.This is a densely-packed and well-written article which gets into a number of other areas: again, please do read the whole article. For instance, his discussion of the role of entropy ties nicely to our previous blog entry, The Quantum Solution to Time's Arrow.
Here's a great video from the TED Talks series featuring astrophysicist George Smoot talking about the structure of spacetime. Dr. Smoot won the 2006 Nobel Prize in physics (along with John Mather) and is a physicist at the University of California at Berkeley. There are some really stunning graphs and animations in this presentation, please do try to watch all 19 minutes. I'm impressed with how Dr. Smoot does such a good job of walking the same line I try to: if our universe sprang from a selection pattern that established some basic rules, some basic laws, and the universe sprang from all that, then what you call the selection pattern doesn't matter. In God 2.0 I talked about the well-known debunker and publisher of Skeptic Magazine, Michael Shermer, who (somewhat surprisingly) says he is quite willing to accept the argument for the existence of a selection pattern that some people call God when it is expressed in these terms.
A direct link to the above video is at http://www.youtube.com/watch?v=c64Aia4XE1Y
I particularly liked the animation Dr. Smoot shows from about the 10:55 mark, because it visually ties so nicely to what we talked about in Nassim Haramein: there's a fractal, recursive, self-similar nature to the structures of our reality, and people who compare images such as those seen in this animation to pictures of the human brain's neural pathways do seem to be on to something very interesting.
If our incredibly fine-tuned universe that allows for the unlikely miracle of our existence is just one out of 10500 possible universes, then statistically speaking we have all hit the most unlikely jackpot imaginable just by virtue of our own existence. A few entries ago, in Poll 44 - The Biocentric Universe Theory, I mentioned the idea that we have new proof that life is a process which exists outside of spacetime. We'll tie these two ideas together next time in "Beer and Miracles".
Enjoy the journey!
Rob Bryanton
Other related entries:
Unlikely Events and Timelessness
Randomness and the Missing 96%
Elvis and the Electrons
"t" Equals Zero
The Big Bang is an Illusion
The Flexi-Laws of Physics
An Expanding 4D Sphere
