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190 points baruchel | 1 comments | | HN request time: 0.228s | source
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zerof1l ◴[] No.44421424[source]
Here's the gist:

For nearly 50 years theorists believed that if solving a problem takes t steps, it should also need roughly t bits of memory: 100 steps - 100bits. To be exact t/log(t).

Ryan Williams found that any problem solvable in time t needs only about sqrt(t) bits of memory: a 100-step computation could be compressed and solved with something on the order of 10 bits.

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zombot ◴[] No.44422352[source]
> log(t)

log to what basis? 2 or e or 10 or...

Why do programmers have to be so sloppy?

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Tarq0n ◴[] No.44422485[source]
This is very common. Log without further specification can be assumed to be the natural log (log e).
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1. griffzhowl ◴[] No.44422511[source]
In information theory it usually means log base 2