How Dangerous is Theoretical Physics?

The String Theorists and the Loop Quantum Gravitators are busily chipping away at the problem what space-time actually is. For some time, my concern has been that if people can figure out how space-time is put together, then somebody might be able to figure out how to take it apart. In other words, the next paradigm shift in theoretical physics may have weapons implications, just like the last one, which gave us nuclear weapons. The atomic nucleus is not Nature's last word on explosive energy release.

That last word is actually the First Word - the Big Bang that began the Universe as we know it. The question is whether some yet to be discovered physics can yield intentional explosions between the intensity of a nuclear explosion and the Big Bang.

On the other hand, our astronomers are finding that planets orbiting around stars are commonplace. With all those planets out there, surely some are home to technological civilizations, and surely some of them have already discovered physics that is several paradigms beyond our own. If there were any explosive technology based on such physics, and if any extra-terrestrial civilization had used it, our astronomers would have seen it. So far, all the observable explosions and other energetic phenomena in space look natural. Or so we think.

Maybe theoretical physics isn't such a dangerous pursuit after all. Maybe.

What a Little Bird Told me about SETI

Dr. Paul Foldes, of blessed memory, once told me this joke:

A small bird was starving one winter. It was so cold, he couldn't fly any more, and he fell to the road. Just then a horse-cart passed over him, and the horse dropped a huge load of dung on him. The dung warmed the bird, and the seeds in it fed him. Soon he was feeling so cheerful he started to hop around and sing. The commotion attracted the attention of a passing wolf, who pulled the bird out of the dung and ate him.

This story has three lessons. First, the one who puts you in deep doo-doo is not necessarily your enemy. Second, the one who pulls you out of deep doo-doo is not necessarily your friend. And third, if you're full of doo-doo, don't draw attention to yourself.

I keep the last lesson in mind when thinking about SETI, the Search for Extra-Terrestrial Intelligence in the Universe. SETI proceeds by combing the universe for radio signals that meet certain statistical criteria for being non-random and non-repetitive - in other words, not of natural origin. But suppose that some ET were out there looking for us. For a long time, say 5 billion years, there would be nothing. Then a faint glimmer of radio signals starting around a century ago. Then analog television shows from about 60 years ago. But this year, television has gone digital - which looks more like random noise to those statistical algorithms. We are going quiet, going out of radio frequency existence after only a century or so. Odds are very slim that any ET would be looking our way during that brief period of time. Which means that odds are we won't be found.

And that is a very comforting thought. Consider the energy it takes for interstellar travel. Let's say that an alien civilization had a spaceship weighing 10 metric tonnes, that it could accelerate to 99% the speed of light. If such a thing experienced brake failure (accidentally or otherwise) it would hit whatever was in its path with an energy of 5x10²⁰ Joules, or 100,000 megatons TNT equivalent. That's more than enough to smash a planet. And we wouldn't even see it coming, because the light from it would be moving barely ahead of it. By the time we detected it, it would be too late think much about it, much less to to do anything about it.

Maybe that's why SETI hasn't found anything. Maybe all those ETs out there have done the same simple calculation that I've just done, and have decided not to draw attention to themselves. Our digital revolution is making us appear to go radio quiet. Let us continue, for in the grand scheme of interstellar society, we may be the little bird.

Are UFOs for Real?

We meet the most interesting people while out walking the dog. An internationally known concert pianist. A marriage and family therapist. A lifestyle and weight management consultant. And today, a cabinet maker who put me onto this video of Mercury astronaut Gordon Cooper recounting his UFO sightings, while in the air, on the ground, and in space (the voiceover narrator is Jonathan Frakes):



Gordo is no spring chicken. Are we seeing the effect of a few TIAs (transient ischemic attacks, aka mini-strokes) which may have altered his memories, or did he decide to embellish his experiences a bit for what seems to be a paid interview, or is he for real?

First of all, the psychiatrist Robert Jay Lifton studied UFO experiencers, and found them to be psychologically normal, and truthful. They are not nuts, and they are not lying. But just because you are sane and telling what you believe to be the truth doesn't mean you can't be mistaken. Second, there are people who have made reasonable arguments that even if Extra-terrestrial Intelligent beings exist, they would probably have so little in common with us that neither we nor they would notice each other, and even if we did, we would have nothing in common we could talk about. As in this article, for example.

But if UFOs really do exist, and if they actually buzz us from time to time, how in the Universe did they find us, and why would they bother? Then again, we have explored every place on earth we could get to, just because we could. And some of us now go to the ends of the earth as tourists just to see the wildlife.

All that, however, leaves the question of why so much secrecy? How could all the governments of the earth manage to collude successfully to keep official records of such encounters from the global public? And why would they continue to bother? The most parsimonious explanation is that there is nothing to hide.

Still, I wonder. If I look up at the sky and smile, will I wind up on Google Earth, or some more distant image archive?