Civilization from scratch

This post is not about AI and not about winter. I have a few of those coming, but this one is about something different. I hope you don't mind.

A friend of mine recently gave a lot to think about by stating the following thought experiment:

Imagine you are taken back in time. To what extent would you be able to advance the civilization of the given era with all the knowledge in your head (no notebooks).

Initially the reaction is obviously that since we all live and breathe the current technical civilization, one should be able to recover almost everything right? There are some many uncertainties to which we already know the answers, so this should be much easier than to get there without such insight?

When you actually give some thought to it, you will realize that things may not be so easy. First of all, in most cases if somebody was taken back in time but left in the same place, they would end up in a middle of nowhere and would have to first survive to even get into contact with any contemporary humans. Say San Diego 300 years ago was an empty costal desert, and … Read more...

Elon and the collective

Elon Musk is a polarizing figure. His ideas frequently come about in casual conversations. People are often amused and impressed by his achievements. I must admit, a few years back I thought he is literally the next Steve Jobs, only actually better, since he was onto so many things... I admired SpaceX, thought that Tesla cars had many great solutions in them...

At some point in 2015 or 2016 Elon started talking outrageous stuff in the domain of AI, a domain of my own expertise, which I could tell right away was total bullshit. And then I began looking at all this stuff in detail. Doing some math here and there. Reading various opinions. As a result, my opinion on Musk and many of his ideas has changed somewhat substantially. At this point, I can pretty much say with confidence that 90% of his stuff is utter BS, and the remaining 10% is perhaps impressive but still questionable.

Nevertheless he is quite a character with many fans almost religiously believing everything he says. Any time I meet somebody who is a Musk fan I have to go over these issues so I decided to write this post as a point … Read more...

Are black holes really so black?

I have long been fascinated with the mysterious black holes. Over the years I've been following the literature and improved my mathematical skills to better understand what we know about these objects. Over the past several years I followed several heated debates related to numerous paradoxes that our understanding of black holes had caused. Here I'd like to present a few issues I have with our contemporary understanding of the subject. If you are a black hole specialist, I will appreciate feedback.

Classical picture

Existence of black holes is a straightforward result of the theory of general relativity (in fact is conceivable even in the classical Newtonian mechanics). In essence the observation is that an object dense enough would eventually reach the escape velocity equal to the speed of light, at which point in becomes black (since it cannot radiate anything out) and anything that happens to get trapped inside it, has no hope of getting out, or at least has the same hope of getting out as we may have the hope of traveling faster than light. The solution of that particular object was first put forward by Karl Schwarzschild who observed that there is a particular size/radius below … Read more...

Optimality, technology and fragility.

This post is a bit of a mixed bag about technology and fragility, a bit about AI and tiny bit on politics. You've been warned.

Intro

Back in the communist and then early capitalist Poland, where I grew up, one could often get used soviet equipment such as optics, power tools etc. Back in the day these things were relatively cheap and had the reputation of being very sturdy and essentially unbreakable (often described as pseudo Russian "gniotsa nie łamiotsa" which essentially meant you could "bend it and it would not break"). There are multiple possible reasons why that equipment was so sturdy, one hypothesis is that soviet factories could not control very well the quality of their steel and so the designers had to put in additional margin into their designs. When the materials actually turned out to be of high quality, such over engineered parts would then be extra strong. Other explanation is that some of that equipment was ex-military and therefore designed with an extra margin. Nevertheless, these often heavy and over-engineered products were contrasted in the early 90's with modern, optimized, western made things. Western stuff was obviously better designed and optimized, lighter, but as soon … Read more...

Inside of a nebula

I'm taking a break from AI in this short post, it's time for something more general about the universe [see the last post in this category "what if we had a warp drive"].

In our daily activities we may not notice how lucky we are - we can see the sky. I mean the deep sky, even far beyond our Galaxy. And by looking at those things, we can learn that the Universe is expanding, that there are quasars, active galaxies, large scale cosmic structures, galaxy clusters, cosmic background radiation and many other marvels. We treat all that as obvious.

But imagine the Sun along with the solar system was trapped inside one of the dense nebulas, which there are countless numbers of in our Galaxy. Say we were trapped somewhere deep inside the Orion nebula.  All we would see in the night sky would be the faint pink glow of hydrogen and maybe a few blurred stars shining through the fog.

And best of all, since the nebula is many, many light years across, we could do nothing to see beyond it. Absolutely nothing. Discovering anything about the outside universe would require sending a probe light years … Read more...

What if we had a warp drive?

Here is something completely different. Nothing today about AI or deep learning.

I'm a big fan of Star Trek and generally like the utopian version of the future that Gene Roddenberry had given us. But obviously this is just a vision and a TV show, so it's full of stuff that makes people watch it. Inspired by that vision though, I've been day dreaming what it would be like if we actually had the 24'th century technology.

This will just be daydreaming exercise, so let us not bother for now on whether faster than light travel is feasible. Clearly with our current understanding of physics it does seem like a very fundamental limitation. But there is some new physics lurking, perhaps looking crazy, but quantum mechanics did look crazy in the beginning (and it still does) and yet has proven to be extremely good at describing nature.

Here are my assumptions:

  • faster than light travel is possible at a rate of say 1 light year per hour. For now let's just assume that the "warp" drive takes the ship into a thin wormhole like tube, so when the ship is in warp mode it cannot interact with matter and
Read more...