Friday, December 3, 2010

The "Multiverse" & Occam's Razor (12/27/2009)

This was originally posted on a horrible site called Myspace. When Myspace underwent a redesign in Fall 2010, hundreds of insightful reader comments that had been left over the years were lost. I have since deleted my account there.

Everyone is talking about the "multiverse" these days — the idea that our Universe is just one of many, that there may be billions of "pocket universes" as real as our own Universe but extremely far away, or in the form of isolated "bubbles," such that we may never be able to contact them. The cover story of the January 2010 issue of Scientific American is "Life in the Multiverse," and the illustrations depict universes connected to each other like grapes on a vine. Once pure speculation and a science-fiction device, this concept of multiple alternate universes is now front-and-center in mainstream physics as well as pop culture.

In part, the motivation has been to explain the "fine tuning" of our Universe: the handful of physical constants which, if any were different by a tiny amount, would disallow the existence of matter and therefore us. Some of these amounts are so minuscule, our Universe seems to balance on a knife-edge between various prohibitions to our existence. While theists consider this proof of an intelligent designer, the prevailing approach among physicists is to invoke the anthropic principle: We must find ourselves in a universe with conditions suitable for life, because if we weren't in such a universe, we wouldn't be around to notice.

This raises a couple of questions. Do we find ourselves in a life-allowing universe because ours ended up this way by accident? Or, is it because there must be many different universes, and we are here because, by sheer numbers, at least one of them must support life? The second has become the conventional explanation.

I wish to challenge this conclusion. It reminds me of a moment in Carl Sagan's Cosmos, during a discussion of past theories about life on Venus. "Observation: Can't see a thing. Conclusion: Dinosaurs!" In this case, it's, "Observation: One universe and one universe only. Conclusion: Billions of universes!"

Imagine you are watching TV through a cable box that's broken (unbeknownst to you) and gets only one channel. You then learn that the cable company is providing hundreds of other channels, and that the signals are getting into your home, even though you've never seen any of them. So, you go searching for the hundreds of other cable wires passing through the wall, and finding none, you conclude that the cables must be there, and must be perfectly real, but they are coming in where you can't find them. Now, is that the only conclusion, or the best conclusion, that could be drawn from what you know? A more elegant solution is that the other channels are coming through the same one cable — the one that you know exists — but for whatever reason, you can see only the one channel.

Similarly, I believe a more elegant solution to the "multiverse" question is that all potential universes are interlaced with the one that we observe, but for whatever reason, we observe only our familiar Universe. In other words, the alternate universes are not real to us in the way that our own Universe is real, but rather, they coexist with ours in a state of potential.

This issue seems to be a good candidate for the conceptual tool known as Occam's Razor. It says that if one solution to a problem requires multiple things with special conditions and assumptions, and another solution has fewer of these requirements, then the simpler solution is preferred. If there is another explanation, why must billions of perfectly real universes "out there somewhere" be required to exist just for ours to be able to exist?

Physicists have no problem describing a light wave as a probability function, a summation of all potential locations for a photon. I don't see why our Universe cannot be viewed the same way as the photon in this example: one possible universe "filtered out" or "made real" among all potential universes, all of which make up one giant probability function. This just seems to be a far more elegant solution than an insane web of billions of individual, discrete "pocket universes." Stop the madness!


  1. How is this solution more simple? Instead of assuming that there are an infinite number of universes you assume that an infinite number of universes superimposed in a large propability field and that "for whatever reason, we observe only our familiar Universe".
    I'm not saying that you are wrong, but I fail to see how this simplifies things.

  2. I agree, Ed. if a multidimensional universe is real, a bubble multiverse would be it's representation on 3d, in other words, wrong, fantasy, if you believe it you take the map for the land.
    now, if there are many universes like bubbles they would have to be all under the same laws of the bubbleverse that would be a bigger version of our own, simple bubble (space-time>4 dimensions), universe.
    I think its cooler to say we live in a 3d world and we are perceiving a 4th dimension, this makes infinite 3D universes that we are "moving through" to perceive this the end of the line we might start a journey through a "5th dimension".

  3. @double
    Ok, so now we believe in stuff because it is "cooler to say" so?
    But I like the way you're postulating a n+1 dimension through which we travel once we're done with the n'th dimension. If you add a few more details to your theory you can start your own religion...

  4. perhaps... i'm no scientist but i'm always facinated that there often seems to be yet another layer/aspect to almost everything in nature as soon as the technology comes along so that we can observe it...
    i also think that that there seems to be only one way to bring order to chaos and thats by using averages(we do it all the time), perhaps the universe is made up of averages the other stuffs there(maybe)just unusual/not looked for/unfound/shortlived, whatever.

    or maybe it's like life in a rainforest a mesh of mutually supportive systems whereby that which doesn't fit in, either adapts or dies out. either because of the challenges it faces from rest of the system or by doing something that eventually bites it in the arse....

    or maybe it's a bit of everything :-)i mean it could be a multiverse of of interverses, or even...

    lol... i mean mr anonymous why knock people for being imaginitive? put your critique forward by all means... jeesh!

  5. Hey Ed. Have you paid any attn to this guy's YT channel?

  6. I have...I applaud him for exploring and publicizing some pretty out-there ideas, but the bits that I've seen didn't impress me all that much. I wish instead that's take one specific concept and explore it in great depth, rather than presenting a laundry list of alternative views.

  7. Ed..Jacques Vallee is no fool in person it seems.Whats his thing..mapped mars,mentions and writes of ufo,s then a billionaire capital venturist .
    re appears again recently sprouts ufo's and dimensions.even has peter sturrock on board??

  8. Hey Ed. There's a poplar youtuber by the name of bill gaede's who has created a handful of videos skewing the current state of physics as being dominated by the religion of "mathematical physics".
    Check his channel out. If anything his videos would probably give you material for your future comedy sketches.

    he has a website too

  9. Interesting. I didn't dive into any of his writings or videos, but his channel and web page don't appear promising. Still, I'll give credit to anyone who's willing to break out of a pack and propose new ideas, even if they're wrong. After all, unless the world is exposed to new ideas, right or wrong, we'll never be find any right ones.

  10. Have you ever heard of the evolutionary multiverse argument? That seems very convincing to me(because I kind of came up with it myself..but later on found out it was not unique.)
    I was struck by the fact if the Big Bang theory is true, then all matter and space and time were at some point packed into an infinitely dense point. What else in Nature has that property? If you think about it for a few seconds, you probably will realize that it is the singularity at the center of a black hole.
    My idea was then the Big Bang occurred due to another universe’s black hole. In other words we are living on the other side of a black hole. I think it’s called a white hole. As I said I found out that this idea is not a new idea. Anyway an argument as to why this universe is so fine tuned for life is as follows:
    In the beginning there was nothing but the laws of physics that is eternal and timeless. Due to quantum fluctuations universes pop in and out of existence. Some of these universes, by chance have constants which would give rise to universes that can create black holes. Those universes which have black holes give rise to daughter universes that birthed from these black holes which then roughly have the same values of these constants but they get refined and refined until eventually there will be a universe or universes with the right set of values of constants so that life could arise. I’m not sure, but I think it is a lot easier to get a universe with the right set of values of the constants to give rise to black holes than to get a universe that happens to have the right set of values of the constants to give rise to life.
    I find this argument really compelling because of its parallels to biological evolution.
    Your idea of an observer created Universe, isn't that basically Wheeler's idea?