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577 points mooreds | 2 comments | | HN request time: 0.001s | source
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staplung ◴[] No.42176496[source]
It's worth mentioning that cable breakages happen quite often; globally about 200 times per year [1] and the article itself mentions that just last year, two other cables and a gas pipeline were taken out by an anchor. The Gulf of Finland is evidently quite shallow. From what I understand, cable repair ships are likely to use ROVs for parts of repair jobs but only when the water is shallow so hopefully they can figure out whether the damage looks like sabotage before they sever the cable to repair it. Of course, if you're a bad actor and want plausible deniability, maybe you'd make it look like anchor damage or, deliberately drag an anchor right over the cables.

Cable repairs are certainly annoying and for the operator of the cable, expensive. However, they are usually repaired relatively quickly. I'd be more worried if many more cables were severed at the same time. If you're only going to break one or two a year, you might as well not bother.

1: https://www.theverge.com/c/24070570/internet-cables-undersea...

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ValentinA23 ◴[] No.42178949[source]
A 1 in 36 million chance for three breaks in one day.

https://mathb.in/80217

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CrazyCatDog ◴[] No.42179837[source]
“Knowing that 200 undersea cables break every year globally, estimate the probability that 3 cables break in the baltic sea on the same day.”

I’m stealing this to use for grad-student mock-interviews—thank you!

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Moru ◴[] No.42181237[source]
Hint: The cables are often very close. If one breaks, the otherone also breaks :-)
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1. CrazyCatDog ◴[] No.42182424[source]
Right, if it’s a case interview, then higher accuracy ought to prompt the interviewee to ask: (1) Do the 200 cuts typically occur in clusters? (2) What’s the typical density, eg are they usually collocated? (as an alternative to the above) (3) Are there pathways that avoid the sea but connect Europe and North America (getting at density in the sea in question) Etc.

That’s what makes this one so good—lots of opportunities to extend or roll-back difficulty.

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2. ValentinA23 ◴[] No.42184900[source]
I was surprised to see so many upvotes this morning and was disappointed when I realized it wasn't for another comment I made about the Anthropic Principle.

My take is that in face of coincidences supporting the emergence of intelligent life, we should expect to observe coincidences unnecessary for the emergence of life too.

An analogy: imagine you have lost the key to your mansion and try to cut one at random out of a metal sheet. If it can unlock the door, then chances are that you cut unnecessary notches (the analogy only holds for warded locks and the key you crafted is a master key).

See: https://news.ycombinator.com/item?id=42178306

I'm wondering where I'm wrong in my reasoning because the implication is weird.