Via GeekPress, Nick Bostrom has a fascinating essay at Technology Review in which he lays out his case for hoping that we don't find evidence that life ever existed on Mars or that it exists elsewhere in the universe. Why would we not want to find evidence of life?

According to Bostrom, the apparent silence of our galaxy -- the lack of even one civilization which has advanced to the galactic colonization stage, which we ought to know about if it ever happened, because they would be here -- is evidence either that there is no life out there or that life is in some way blocked from developing to that level. He talks in terms of a "great filter" that evolving life must pass through on the way to the galactic colonization stage. If life is evolving out there in the galaxy, and no aliens have ever shown up here, that suggests that no life anywhere has ever successfully made it through the filter. And if nobody else ever makes it through the filter, we have very little reason to hope that we ever will.

The filter could take many forms. It could be some stage in biological evolution that is just plain difficult to get through. For example, if life rarely makes it to the stage of producing multicellular organisms, and that's the reason nobody is out there, then we've already passed through the filter and it would seem that we are in the clear.

Woo hoo! Let's start colonizing the galaxy.

Continue reading "The Great Filter" »

Posted by Phil Bowermaster at 07:07 AM | Permalink | Comments (2)

Years ago I remember reading a book by Isaac Asimov (one of his many collections of essays) in which -- if I recall correctly -- he provided answers to questions that he had never addressed before, or that wouldn't have been a good fit for any of his other books. One of these questions was, "What lies beyond the universe?"

Asimov's glib initial response was "non-universe." He then spent some time talking about what non-universe might be. Whatever it is, one would think that it would also be the correct answer to the question, "What came before the universe?"

But maybe not:

Before the Big Bang: A Twin Universe?
Until very recently, asking what happened at or before the Big Bang was considered by physicists to be a religious question. General relativity theory just doesn’t go there – at T=0, it spews out zeros, infinities, and errors – and so the question didn’t make sense from a scientific view.

But in the past few years, a new theory called Loop Quantum Gravity (LQG) has emerged. The theory suggests the possibility of a “quantum bounce,” where our universe stems from the collapse of a previous universe. Yet what that previous universe looked like was still beyond answering.

Now, physicists Alejandro Corichi from Universidad Nacional Autónoma de México and Parampreet Singh from the Perimeter Institute for Theoretical Physics in Ontario have developed a simplified LQG model that gives an intriguing answer: a pre-Big Bang universe might have looked a lot like ours. Their study will appear in an upcoming issue of Physical Review Letters.

“The significance of this concept is that it answers what happened to the universe before the Big Bang,” Singh told PhysOrg.com. “It has remained a mystery, for models that could resolve the Big Bang singularity, whether it is a quantum foam or a classical space-time on the other side. For instance, if it were a quantum foam, we could not speak about a space-time, a notion of time, etc. Our study shows that the universe on the other side is very classical as ours.”

So if a pre-Big Bang universe looked a lot like ours, does it follow that our universe looks a lot like a pre-Big Bang universe? Remember the old computer programming joke that goes...

__AM I IN A LOOP?

__AM I IN A LOOP?

__AM I IN A LOOP?

__AM I IN A LOOP?

The idea that our universe sprang from one much like it puts me in mind of Friedrich Nietzsche's idea of eternal recurrence. Corichi and Singh talk in terms of our universe being a lot like the one that came before it, but nothing I read above rules out the possibility that this universe is a dead ringer for its ancestor. If that were the case, if the current universe were an exact copy of the one that came before, it would only be reasonable to expect that the next one will also be exactly the same. Or as Nietzsche put it:

This life as you now live it and have lived it, you will have to live once more and innumerable times more; and there will be nothing new in it, but every pain and every joy and every thought and sigh and everything immeasurably small or great in your life must return to you-all in the same succession and sequence-even this spider and this moonlight between the trees, and even this moment and I myself. The eternal hourglass of existence is turned over and over, and you with it, a grain of dust.

How many times have you read this blog post? How many times have I typed it? Is it possible we have each done these things a dozen or a hundred or a billion times, and that we will continue doing so for all eternity?

Also -- and this is the part that makes my head twinge just a bit -- if it is exactly the same thing occurring over and over and over and over...exactly the same...does it really make sense to talk in terms of the number of times it happens? Is one instance of the universe somehow different from an infinite repeating series of the same universe? How? And to what observer?

UPDATE: Michael Darling directs us to this talk by Stephen Hawking, in which he asserts that the universe could have spontaneously created itself out of nothing. As far as satisfactory explanations go, this one has to be the bottom of the barrel. Which doesn't mean it's wrong, of course.

Posted by Phil Bowermaster at 05:22 PM | Permalink | Comments (6)

Now this is just darned interesting:

The secret of the Universe is not 42, according to a new theory, but the unimaginably larger number 10^122. Scott Funkhouser of the Military College of South Carolina (called The Citadel) in Charleston has shown how this number — which is bigger than the number of particles in the Universe — keeps popping up when several of the physical constants and parameters of the Universe are combined1. This ‘coincidence’, he says, is surely significant, hinting at some common principle at work behind the scenes.

How about this? What we've manged to do is to uncover a little bit of the source code with which the computer program that we call "the universe" was written. We can see patterns in the code -- amazing numeric coincidences! -- but we still don't know its rules, syntax, etc.We're astounded to find these "coincidences" that would immediately stop being astounding if we knew anything about this underlying structure.

But this raises the question -- which I think we've tossed around before -- about whether source code is merely an analogy, or whether things like this numeric coincidence provide us an extremely remote and yet valid view into the minds of someone, or some group of beings, who exist (or existed) entirely outside of this universe and are responsible for its being here.

And even if it is a remote and very faint view that we have, i think we can say one thing for certain about these beings.

They're geeks.

Posted by Phil Bowermaster at 06:06 AM | Permalink | Comments (0)

I know. You're supposed to start these things with the bad news so as to make the good news seem better, but believe me, it's just more fun to approach this one the other way around.

So with that in mind...

The good news: You know that whole mysterious thing about how the most distant parts of the universe are accelerating? Remember how it threw so much scientific thinking into disarray? Remember all the problems and confusion it caused? Well, the good news is that maybe the outer edges of the universe aren't really accelerating at all. Some clever scientists have come up with an alternative explanation.

Which leads us to...

The bad news: So, okay, their alternate explanation is that time itself may be slowing down. At first, time slowing down doesn't seem to be that big a deal. But it's one of those things that sort of catches up with you eventually. Still, it probably isn't something that we need to get all that worked up about:

In some number of billions of years, time would cease to be time altogether - and everything will stop.

"Then everything will be frozen, like a snapshot of one instant, forever," Prof Senovilla tells New Scientist magazine. "Our planet will be long gone by then."

So to recap: the good news is that maybe the universe isn't weird in a way that we thought, and the bad news is that maybe it's weird in a completely different way that will eventually be the end of everything. But the other good news is that this will only be a problem for those of us planning to live many billions of years. And since most of us planning to do that a also plan to end up functioning in a different substrate -- probably silicon, for starters -- we can look forward to much faster mental function, which will give us a bit of a subjective offset where time coming to an end is concerned.

Plus, we can't rule out subjective immortality kicking in there somewhere down the line. Could happen. We just need to get it started at some point before that final tick of the Big Ticking Clock.

Oh, well. Nothing like a deadline to inspire productivity, I suppose.

Posted by Phil Bowermaster at 06:34 AM | Permalink | Comments (2)

There's some good discussion here on Nick Bostrom's argument concerning whether our universe is or is not a simulation. We discussed that idea here. A quick recap of Bostrom's argument:

Bostrom argues that one of the following three propositions is most likely true:

(1) the human species is very likely to go extinct before reaching a “posthuman” stage;

(2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof);

(3) we are almost certainly living in a computer simulation.

I'm starting to like Option 2. Advanced civilizations might run partial simulations of universes, but why simulate an entire universe? Assuming the Many Worlds Hypothesis to be true, any simulation you might want to create is already out there. Accessing and observing those other universes would be no easy task, but then neither would running a simulation of an entire universe.

So I think posthuman civilizations don't run universe-level civilizations, for the same reason that nobody is trying to build a fully operational replica of Hawaii out in the Pacific. Why go to the trouble? Hawaii is already there.

Posted by Phil Bowermaster at 07:54 AM | Permalink | Comments (3)

Awhile back I fumbled around with the ultimate question - why does anything exist? Wouldn't it have been easier for nothing to exist?

No matter how dogmatic some people seem to be on this issue - both those who believe in God and those who don't - the truth is nobody knows. That being the case, I think humility is the proper response.

I found it interesting to read the thoughts of a couple of guys who don't believe in God - Martin Stritz and George Dvorsky.

Martin almost talks himself into believing God - at least in the Einsteinian sense.

Posted by Stephen Gordon at 06:09 PM | Permalink | Comments (0)

Phil Plait at Bad Astronomy gives us the run-down on Martin Bojowald's Big Bounce Theory of how our universe came into being:

What Bojowald’s work does, as I understand it (the paper as I write this is not out yet, so I am going by my limited knowledge of LQG and other theories like it) is simplify the math enough to be able to trace some properties of the Universe backwards, right down to T=0, which he calls the Big Bounce. The previous Universe collapsed down, and "bounced" outward again, forming our Universe. No doubt the physical aspects of this previous Universe were somewhat different; the quantum uncertainties at the moment of bounce would ensure that. It may have been much like ours, or it may have been quite alien. In his equations, it’s the volume of that previous Universe that cannot be determined. How big was it? It may literally be impossible to ever know.

In the traditional model, talking about anything happening "before" the Big Bang is meaningless. Time doesn't really start until the the Bang occurs. Not that that stops people from talking about it anyway. I know that I, for one, tend to assume that if there are multiple universes, there must be some kind of larger time that could be observed in the relationships between them -- if such relationships ever could be observed! The Big Bounce is intriguing, but if not quite weird enough for you, Plait also directs us to some information on Brane Theory:

For an eternity, our universe lay dormant—a frozen, featureless netherworld. Then, about 15 billion years ago, the cosmos got an abrupt wake-up call.

A parallel universe moving along a hidden dimension smacked into ours. The collision heated our universe, creating a sea of quarks, electrons, protons, photons, and other subatomic particles. It also imparted microscopic ripples, like ocean waves crashing on a shore.

These ripples generated tiny fluctuations in temperature and density, the seeds from which all cosmic architecture—from stars to gargantuan clusters of galaxies to galactic super clusters—ultimately arose.

So in this model, if that other universe had never slammed into us, our universe would never have been anything more than a sort of potential universe. Raising the question of how long (in that larger, inter-universal time) did we have to wait before coming into existence?

Just a little something to ponder as you start your week.

Posted by Phil Bowermaster at 07:02 AM | Permalink | Comments (3)

In our recent discussion about whether this universe is a simulation (and what use intelligent beings might make of simulated universes), Stephen wrote the following:

Why not bring the simulated minds into their world at that point? In fact, wouldn't that be an efficient way to keep the exponential progress of a Singularity going? A post-Singularity civilization could literally bring more and more post-Singularity minds into the "real" world via full simulations of other realities up to the point of their Singularity.

Maybe the beings in the lower-level realities do bring the simulated beings into the "real" world once they achieve Singularity status. Moreover, maybe the same identities or personalities keep showing up in different simulations until they're lucky enough to make it to one that's on the brink of Singularity. What if the software program that makes me me has shown up in many thousands (or millions) of simulated universes, but this is the first time I've been around (potentially) for the Big Leap? Once I'm in the real world post-Singularity, perhaps I will have access to all those different versions of myself that have been run in the other simulations.

This could be seen as a slightly askew take on the soul, reincarnation, and Nirvana. Sure, it sounds a little sketchy, but it's got to be at least as likely as, say, quantum immortality. Or, come to think of it, maybe it's a restatement of the same idea.

UPDATE: As I re-read this, it looks like I have substituted a mathematical model of the soul for the traditional, metaphysical model without explaining how such a thing could exist. I mean, it isn't much of a leap to say that Phil Bowermasters who lead pretty much the same life I do -- or some divergent version of the same life -- over in another simulation/parallel universe would be the same guy I am. But could there be other people in other times and places who are the "same" person as I am. That's a tougher nut to crack.

Posted by Phil Bowermaster at 07:27 AM | Permalink | Comments (1)

I wonder what the relationship is between Gardner's Intelligent Universe and Nick Bostrom's Simulation Argument.

A quick recap of the latter: Bostrom argues that one of the following three propositions is most likely true:

(1) the human species is very likely to go extinct before reaching a “posthuman” stage;

(2) any posthuman civilization is extremely unlikely to run a significant number of simulations of their evolutionary history (or variations thereof);

(3) we are almost certainly living in a computer simulation.

The full argument is lots more fun than any abbreviated version could possibly be, so don't cheat yourself. At first blush, it looks to me as though a simulated universe would fit pretty well with Gardner's idea of a carefully designed intelligent universe. If our universe is a simulation, it explains why so much of what we observe appears to be "rigged" in favor of life in general and us in particular.

But then, why were things that way in the original universe, which we're now simulating? Was it a simulation, too? Or maybe things weren't that way at all in our ancestor universe. Maybe this universe is some kind of bizarre jazz riff on the original. In which case, why does it seem so...mundane? You would think that a wholly (or largely) original universe ought to have some magical stuff in it, or else what's the point?

On the other hand, of course it would all seem mundane to us. Maybe light or gravity are wonderfully exotic concepts, notions that would amaze and delight the inhabitants of the original universe. And perhaps their everyday reality would delight and amaze us. We'll probably never know.

But then again...

UPDATE:

I followed my own link to begin re-reading Bostrom's essay when something caught my attention that I had skimmed over before:

Simulating even a single posthuman civilization might be prohibitively expensive. If so, then we should expect our simulation to be terminated when we are about to become posthuman.

Criminy, now there's a thought. Is anybody at the Lifeboat Foundation working on that possibility?

UPDATE FROM STEPHEN:

So, Bostrom would have us choose one of the three...

Well, I definitely don't buy #2. It seems very likely that any post-Singularity civ would run many, many simulations of its past (or even very weird variations on reality). Alternate history is already an important genre of fiction in this reality.

So I guess I'm left on the fence between #1 and #3. I don't really like either - particularly if Bostrum is right about our simulation being terminated at the point of Singularity. It's death by funnel (#1) or reboot (#3). It's the Fermi Paradox meeting The Doomsday Argument in The Matrix.

Anyway, let's throw out #2 because it is implausible and let's discount #1 because...well I'd rather not believe it. Call it hope. So, I'm left with #3 and Bostrom's rather depressing thought that a post-Singularity civilization might terminate our simulation at the moment of Singularity.

But wait. I think Bostrum is thinking pre-Singularity. Why would a post-Singularity civilization that's running a simulation terminate a civilization at the point of Singularity? Lack of computing power? Naahhh.

Why not bring the simulated minds into their world at that point? In fact, wouldn't that be an efficient way to keep the exponential progress of a Singularity going? A post-Singularity civilization could literally bring more and more post-Singularity minds into the "real" world via full simulations of other realities up to the point of their Singularity.

This would answer the Fermi Paradox and The Doomsday Argument and the puzzling Anthropic Principle. Of course this universe was built to favor life. The civilization that's simulating our universe wants more post-Singularity minds.

Why not just make minds in their reality rather than go to all the trouble of simulating a universe? Perhaps because there is some advantage to the diversity of minds that might develop in different realities.

Just a thought.

Posted by Phil Bowermaster at 08:04 PM | Permalink | Comments (4)

Wired has a run-down on some big questions that remain unanswered (or partially answered). My favorites are:

How can observation affect the outcome of an experiment?

Why is fundamental physics so messy?

How does the brain produce consciousness?

Is the universe actually made of information?

That last one is a good question to mull over when you have some time on your hands (say, for example, when flying across the Pacific.) If everything is information, it explains quite a bit. For example, it explains why the universe seems so inordinately fond of the stuff, as demonstrated by billions of years of MEST compression and the Law of Accelerating Returns. An intriguing, related idea -- if it is not, in fact, just a restatement of the same idea -- is articulated by this guy, who suggests, if I understand him correctly, that the universe is made of numbers. But then he also argues that (maybe) the universe contains virtually no information, so perhaps I'm missing something.

The four questions listed above may be more closely connected to each other than we realize. Consciousness would appear to emerge from information acting upon itself. I am of the opinion that intention is one of the key enablers of this interaction. But then again, it could be one of its results. Observation is another key enabler and/or result of this mysterious interaction. Conscious observation plays some role in the resolution of quantum outcomes. Maybe it enables us to slightly tweak or mess with outcomes. Or maybe it's what's driving the whole show.

One problem that the "universe is made of information" formulation does not solve is the ultimate question: why does anything exist at all? We get to keep chewing on that one irrespective of whether information is a cause, or result, of the existence of the universe.

I noticed that several responses to the various questions (not necessarily just the ones I listed above) made reference to the Large Hadron Collider, which is going on-line soon. We're hoping that the LHC is going to answer a lot of questions for us, but why do Iget this sneaking suspicion that it might raise as many questions as it answers?

Posted by Phil Bowermaster at 01:54 PM | Permalink | Comments (5)

Weirdest cosmology theories. Via GeekPress.

Personally, I think they left off a really good one.

Posted by Phil Bowermaster at 05:54 PM | Permalink | Comments (0)

Because, hey -- we believe in equal time:

Here's how to build a universe. Step one: start at the beginning of time. Step two: apply the laws of physics. Step three: sit back and watch the universe evolve. Step four: cross your fingers and hope that it comes out looking something like the one we live in.

That's the basic prescription for cosmology, the one physicists use to decipher the history of the universe. But according to Stephen Hawking of the University of Cambridge and Thomas Hertog of the European Organization for Nuclear Research (CERN), the steps are all backward. According to these physicists, there is no history of the universe. There is no immutable past, no 13.7 billion years of evolution for cosmologists to retrace. Instead, there are many possible histories, and the universe has lived them all. And if that's not strange enough, you and I get to play a role in determining the universe's history. Like a reverse choose-your-own-adventure story, we, the observers, can choose the past.

Three things I like about this notion of the "flexiverse:"

1. It comes from Stephen Hawking

2. It suggests that time and space may be infinite. This is kind of a leap on my part; I don't see Hawking addressing that issue directly. Of course, even if the flexiverse is infinite the model doesn't necessarily make any provision for accessing space beyond the tiny playground with a diameter of 15-20 billion light years of which you can observe a small portion on any starry evening, nor does it provide any means of accessing time other than our plodding one-day-every-24-hours approach.

3. In this model, we get to be the turtles. High time, says Phil. High flippin' time.

On the inevitable question of the theological implications, Hawking does his standard coy thing

SUE: To oversimplify your theories hugely, and I hope you'll forgive me for this, Stephen, you once believed, as I understand it, that there was a point of creation, a big bang, but you no longer believe that to be the case. You believe that there was no beginning and there is no end, that the universe is self-contained. Does that mean that there was no act of creation and therefore that there's no place for God?

STEPHEN: Yes, you have oversimplified. I still believe the universe has a beginning in real time, at the big bang. But there's another kind of time, imaginary time, at right angles to real time, in which the universe has no beginning or end. This would mean that the way the universe began would be determined by the laws of physics. One wouldn't have to say that God chose to set the universe going in some arbitrary way that we couldn't understand. It says nothing about whether or not God exists - just that He isn't arbitrary.

With all due respect to "Sue," I think she's asking the wrong question. As Stephen (Gordon) has pointed out more than once, there is no model of the universe that conclusively eliminates the role of the Creator. So asking whether a particular model does that is kind of a waste of time.

It would be better, IMHO, to ask whether there is a suggestion of infinity here, and what a demonstrably infinite (as distinct from "finite and boundless") universe has to say about what is or is not possible. Wouldn't the ontological argument for the existence of God -- especially Goedel's formulation thereof -- get a boost from the assertion that the universe is infinite?

And I'm just asking. One thing the ontological argument and this flexiverse model have in common -- they both give me a headache.

Posted by Phil Bowermaster at 12:46 PM | Permalink | Comments (5)

...would be an improvement. Left to my own devices, my philosophical speculations tend towards solipsism supported by the odd tautology. Instinctively, I've always sensed that that kind of thinking was wrong.

Here, at last, is a graphical demonstration of what I believe the problem to be.

Bonus: In the process of looking for this animation, I came across this page full of neat stuff. Enjoy.

Posted by Phil Bowermaster at 08:24 PM | Permalink | Comments (0)

...if they found something, and it was Morse Code to the effect of "The Lutherans got it right, but only the Missouri Synod Lutherans. Everyone else, thanks for playing."

Carl Sagan had a similar idea in his novel Contact, where the signature was left (I believe) in...

SPOILERS AHEAD

Continue reading "Wouldn't it be Funny..." »

Posted by Phil Bowermaster at 11:40 AM | Permalink | Comments (2)

Here's some interesting research:

The physical constants of the Universe are thought to have remained unchanged since the Big Bang; many predictions made by cosmologists depend on it. An international team of researchers are using the National Science Foundation's Robert C. Byrd Green Bank Telescope (GBT) to see if things really have gone on unchanged for billions of years. They're looking to measure two universal constants: the ratio of mass between protons and electrons, and something called the fine structure constant.

If those cosntants have nudged even slightly over the eons, the implications are staggering.

Hat-tip: Posthuman Blues.

Posted by Phil Bowermaster at 06:58 AM | Permalink | Comments (0)

I think this idea sounds a lot like this one. Here's my favorite part:

String theory, according to Susskind, presents a compelling explanation of why the cosmological constant is so small, without invoking an intelligent designer. The answer lies in what Susskind calls "the Landscape," which is the set of all possible universes that are compatible with string theory. The Landscape can be thought of as having various locations, corresponding to different values of the cosmological constant and other parameters. In Susskind's estimate, the Landscape contains 10⁵⁰⁰ types of possible universes -- a stupendously large number far bigger than a googol (which is 10¹⁰⁰.)

10⁵⁰⁰ types of universes seems like a good start. But I wonder...how many do we get of each type?

Posted by Phil Bowermaster at 04:06 PM | Permalink | Comments (7)