There's no One True Definition of what it means to be fractal, but a lot of working mathematicians use the criterion that a space's Hausdorf dimension is not equal to its topological dimension. Oftentimes (but not always), the Hausdorf dimension will be fractional, which is where the word comes from. Self-similarity is an easy way to satisfy that requirement in a way that's easy to explain, but it's far from the only way.
I was under the impression that the fractal dimension must be greater than the topological dimension for the space to be a fractal.
And that the fractal dimension is usually equivalent to the mincowski dimension (the limit of the area measured by finite boxes as the size of the boxes grows arbitrarily small) and hausdorf dimension (the limit of the perimeter as measured by an aproximting polygon with equal length sides as the number of sides grows arbitrarily large) along with others.
The article posits that maybe advanced alien civilizations may be motivated to build larger (and hence harder to to detect) Dyson spheres for the efficiency gains. While that's a possibility, it's also possible that being harder to detect is an end unto itself for safety reasons.
> A common example to help explain sunk costs is the movie theater experience, where a person buys a ticket and, 20 minutes into the movie, she realizes that it is a horrible movie and it will only get worse.
Offtopic I know, but twice in my life I've walked out of a terrible movie at the theater within the first 30 minutes and gotten a refund from the manager. Don't think you have to sit through terrible movies!
That is absolutely absurd to me. I understand walking out, but getting the refund had to have caused some eye rolls and jokes at your expense after you walked out. Where does it end? Can you walk out and get a refund because you didn't like the last 20 minutes? I think this sort of speaks to the absurdity of some aspects of this "get mine" mentality cultivated among economists
One thing you might notice when traveling a lot, the US attitude towards refunds (ie. when reasonable, and I would argue even when "slightly" unreasonable in the interest of customer service) differs a LOT from most countries attitude towards refunds (which can be summarized as essentially only when convicted in a court of law - and even then)