Category: cosmology

Spurting into the Undiscovered Country

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voyager_plaqueThere was glop on the windows of the International Space Station. Outside. It was algae. How? Now that is unclear, but there is a recent tradition of arguing against abiogenesis here on Earth and arguing for ideas like panspermia where biological material keeps raining down on the planet, carried by comets and meteorites, trapped in crystal matrices. And there may be evidence that some of that may have happened, if only in the local system, between Mars and Earth.

Panspermia includes as a subset the idea of Directed Panspermia whereby some alien intelligence for some reason sends biological material out to deliberately seed worlds with living things. Why? Well, maybe it is a biological prerogative or an ethical stance. Maybe they feel compelled to do so because they are in some dystopian sci-fi narrative where their star is dying. One last gasping hope for alien kind!

Directed Panspermia as an explanation for life on Earth only sets back the problem of abiogenesis to other ancient suns and other times, and implicitly posits that some of the great known achievements of life on Earth like multicellular forms are less spectacularly improbable than the initial events of proto-life as we hypothesize it might have been. Still, great minds have spent great mental energy on the topic to the point that elaborate schemes involving solar sails have been proposed so that we may someday engage in Directed Panspermia as needed. I give you:

Mautner, M; Matloff, G. (1979). “Directed panspermia: A technical evaluation of seeding nearby solar systems”. J. British Interplanetary Soc. 32: 419.

So we take solar sails and bioengineered lifeforms in tiny capsules. The solar sails are large and thin. They carry the tiny capsules into stellar formations and slow down due to friction.… Read the rest

A Paradigm of Guessing

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boxesThe most interesting thing I’ve read this week comes from Jurgen Schmidhuber’s paper, Algorithmic Theories of Everything, which should be provocative enough to pique the most jaded of interests. And the quote is from way into the paper:

The first number is 2, the second is 4, the third is 6, the fourth is 8. What is the fifth? The correct answer is “250,” because the nth number is n 5 −5n^4 −15n^3 + 125n^2 −224n+ 120. In certain IQ tests, however, the answer “250” will not yield maximal score, because it does not seem to be the “simplest” answer consistent with the data (compare [73]). And physicists and others favor “simple” explanations of observations.

And this is the beginning and the end of logical positivism. How can we assign truth to inductive judgments without crossing from fact to value, and what should that value system be?… Read the rest

Keep Suspicious and Carry On

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I’ve previously argued that it is unlikely that resource-constrained simulations can achieve adequate levels of fidelity to be sufficient for what we observe around us. This argument was a combination of computational irreducibility and assumptions about the complexity of evolutionary trajectories of living beings. There may also be an argument about the observed contingency of the evolutionary process that is an argument against any kind of “intelligent” organizing principle though not against simulation itself.

Leave it to physicists to envision a test of the Bostrom hypothesis that we are living in a computer simulation. Martin Savage and his colleagues look at Quantum Chromodynamic (QCD) theory and current simulation methods for QCD. They conclude that if we are, in fact, living in a simulation, then we might observe specific inconsistencies that arise from finite computing power for the universe as a whole. Those inconsistencies would be observed in looking at the distribution of cosmic ray energies, specifically. Note that if the distribution is not unusual the universe could either be a simulation (just a sophisticated one) or could be a truly physical one (free running and not on another entity’s computational framework). It is only if the distribution is unusual that it might be a simulation.… Read the rest

The Universe is Smeary Stuff

Mark Davis4 Comments

What should our expectations be regarding scientific theories? That question regularly bobs to the surface for me. When I taught physics in the Peace Corps over twenty years ago I worried over it. And now, with an inquisitive thirteen-year-old curious about the recent results from the pursuit of the Higgs Boson asking me questions, I continue to think that the conceptual shifts requisite for scientific understanding are perhaps as important as the science itself.

You see, none of it makes simple, clean sense. And none of it makes sense precisely because there is no conceptual similarity between our everyday scales of interaction and those of the mega and the micro. They are baffling and complex and not fully understood. We should take great pride in this, as human beings. We should revel in the rise of experimentation and rationality that has led us to this baffling precipice. We should not back away into the gray simplicity that predates what our scientific investigations have brought us to, because they make enough sense that they can be understood with some effort. But the urge is there; relent at the scale, scope, and complexity of the edifice that is required to get even basic traction. It either doesn’t impact me or is inhuman at some level.

But it needn’t be. The Higgs Boson is simply badly explained because it it based on preserving explanatory footholds that relate to everyday physics of cars and bowling balls. Drop that assumption and things get both weirder and simultaneously simpler. The universe appears to be composed of stuff that has a holographic quality to it in the sense that holograms replicate images throughout their structure. Break a piece off of a hologram and you can still see the image in it.… Read the rest

Apache Point Memories

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When I was eight or nine, I traveled with my father up into the rarefied air of the Sacramento Mountains of Southern New Mexico. Getting there was long, hot and complicated. Our VW van pushed up over the mountain passes as thunderheads rolled in from the west, plum and steel-gray, and the sky flashed and shuddered under the monsoonal effects of the late-summer deserts. I avoided touching the metal surfaces of the VW van as my father, a professor of electrical engineering, explained how the lighting, were it to hit the car, would likely melt the tires and travel through the shell of the van and into the ground below.

We were in search of another kind of lightning, however, as we passed through the Border Patrol check-point near White Sands and ascended into the Ponderosa Pines of the high, western mountains. The van chugged along but kept ascending and any limitations it may have had were lost on my youthful mind as the smell of pine needles and the cooler air rolled in through the open windows until we finally slowed to a crunching stop in a gravel lot near a couple of unimpressive shacks. We were above the clouds, with just the tops of the cumulonimbus visible to the south and west.

I knew that I was at a place called Sunspot and that there were telescopes there that were used to look at the sun. It was an act of technological disregard of the countless warnings I had received about looking at the sun as a child, including when my father brought home dense smoked filters from the Naval Observatory in Washington DC when I was four to let us watch a full solar eclipse.… Read the rest