In "Where Is My Flying Car", Hall argues that what we really value in cities isn't necessarily physical density, but *temporal* density—ie low travel time. If all points were 5x further apart, but we move 5x faster, we'd prefer it: everyone could have more space. Is this right? /
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One reason I like cities is definitely proximity to services and friends. Dozens of excellent restaurants and people within a thirty minute trip. But I also like running into people randomly, serendipitously. Living in a city is like shaking a fuller snow globe!
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Not sure if temporal density is equivalent to physical density for the purposes of serendipity. If I only run into people at destinations, then there'd be no change if everything were spread out: the same people visit the same restaurants. But I run into people while walking!
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Anyway, this book probably has the highest viewquake/page ratio of the year for me! I thought it was going to be about the history/prospects of flying cars… but that's just a framing device for a sweeping discussion of tech bottlenecks+possibilities.
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One fun way to describe this book: the narrative is a sort of glue which holds together a non-stop parade of Fermi estimates.
These results are probably much less surprising to a physicist, but snippets like this are truly shocking to me!
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I recently moved from NYC to Houston and found something similar: in both cities nearly everything I wanted to do was just 15-30 minutes away, yet the difference in walk / subway vs car *completely* changed my willingness, serendipity, and perception of / to do those things.
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Additionally: walking is dramatically preferable to all other forms of transportation. It’s good for you, improves mood, allows improvisation, is extremely convenient, etc. Taking a flying car quickly between distant locations doesn’t provide any of that.
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True although n.b. I would very much like the flying car additionally/anyway!



