The Zero-Armed Bandit | Hacker News Reader

The Zero-Armed Bandit

damninteresting.com

175 pointsThorondor49 comments

Amazing that it took basically a confession to find these guys, what a different world it was 35 years ago.

Reminds me of the YouTube video on never talking to the police. A key tactic being to get you to say even one tiny little lie, if they can disprove anything you said, however irrelevant to the case, you've committed a serious felony and are now their pawn.

My friend is a prosecutor and said basically the same thing. She recommended that any time the police read your rights and just want to ask you questions - immediately ask for a lawyer. Just keeps things much, much simpler for you.

Not everyone can afford the time or money invested in such an interaction. It is very, very valuable to understand your rights yourself.

Not sure if this is the one, but I'm rewatching it anyways: https://www.youtube.com/watch?v=6wXkI4t7nuc

Previous discussion https://news.ycombinator.com/item?id=9725851 (two weeks ago)

I was really hoping for an retrospective about a multi-armed bandit learning algorithm that ran in production but never experimented, effectively yielding a "zero-armed bandit".

Wow. Giving understandable instructions is important.

I had never heard of this. Fascinating.

This is why I read HN!

Bureau agents acknowledge that it is unlikely that even modern bomb squads and technology could make much headway disarming Big John's improvised explosive without setting it off.

Any (3D?) imaging technology that would allow seeing inside the upper box with enough resolution to determine the wiring?

Also:

The inside surfaces of the boxes were lined with rubber sheeting, which were in turn lined with conductive foil. If something metal such as a drill bit or saw blade penetrated the outer metal casing and the rubber sheeting, it would close a circuit between the metal housing and the foil.

How about cutting tools made of non-conductive materials?

Scrap from the foil and the metal housing is also conductive.

> Any (3D?) imaging technology that would allow seeing inside the upper box with enough resolution to determine the wiring?

Sure, which one? This is not CSI

They were X-raying it already, so if they did it from enough angles they would probably be able to do something like this:

https://en.wikipedia.org/wiki/Industrial_computed_tomography...

The best bet might have been to freeze the battery so it couldn't set off the blasting caps. Possibly by pouring liquid nitrogen into the top box through the panel with the switches.

Would liquid nitrogen trigger the float switch?

If you got enough liquid in there, yes, but I think it's really unlikely you'd get that far. Until you've cooled things down, the liquid you put in is going to boil off, which has a corresponding volume expansion of almost three orders of magnitude. Without good ventilation (which you're not going to get if you're not cutting into the box because of the contact switches) this is going to lead to an explosive pressure buildup in the box, which seems like a really bad idea under the circumstances. There are lots of other possible ways for it to go wrong, e.g. the wires could break under thermal stress, which might lead to bad things; the boiloff could disturb the pendulum in the tilt sensor; etc.

Yeah, and there was allegedly a pressure sensor in there too, which could trip it when the gas expands. Tricky.

Maybe they could have tried to deplete the battery somehow? This is all academic of course.

Should have included visible light/IR sensors inside the control box. Second-line defense against opening the box, first-line defense against x-raying the box.

Think of the ingenuity in crafting the device, and his business savvy to go from landscaper to millionaire (in the 70s). So much drive, and yet not enough to get himself to a GA meeting. Addiction's a bitch.

Could they just have put a box over it and then covered it in concrete? First thing that comes to mind, not sure why it wouldn't work.

The concrete would have to cure properly to have any significant effect, which takes time on the order of weeks.

It wouldn't work because the bomb was full of nitroglycerin. Concrete is strong but it would only possibly dampen the explosion. Also recall that the bomb was set to detonate without any delay if it was subject to even slight vibration. I wouldn't have volunteered to cover it in concrete.

One way to turn a crappy bomb into a really powerful one is to constrain it in something that can be fractured.

There are 'blast blankets' used in demolition and highway construction that are balasted but still open enough that the explosion itself can vent. Basically the effect is to reduce the slope of the build-up of pressure which significantly reduces the amount of damage an explosion will do.

I obviously don't know, but I'm hard pressed to believe that the people involved didn't consider simpler methods before determining the method most likely to succeed was to use C4.

All I'm saying is that there's probably a good reason for the route they went with.

If I could talk to the bomber, I'd want to know- why actually use explosives? At the moment the main explosion goes off, your plot is over and your bomb is useless. At that point, you're not getting any money, and it's now a question of "will you get caught by the feds". And if you do get caught, having used dud explosives can only be to your benefit.

My guess is that maybe dogs can sniff the device and check whether it's actually TNT or dynamite.

except they didn't, and couldn't. I was suggesting using clay or putty, perhaps with a light sprinkling of TNT for flavor. THAT would be equally terrifying but much less dangerous.

You only need enough to make the dog alert, which is not much at all. Dogs don't weigh, they detect.

Lets say you don't get caught.

Device 2 is going to get a whole lot more respect.

respect implies people knowing who you are. which kind of implies getting caught :-)

Not necessarily. You may be known and respected as "the guy who robs casinos using bombs full of switches", or Switchbomber for short :).

He never saw his sons again... He died of liver cancer at the Southern Nevada Correctional Center

This makes me sad. No matter what you did in life, all the ups and downs you go through, to die alone like this...

spoiler... Honestly, I read up to the climax believing it was a hoax, never thought for a moment it was actually a real bomb! Here's a thief, decieve and steal. What good is it too have a armed bomb in the box.

The extortion demand was for $3M. The repair bill was $18M. The bio of the mastermind stated that he lost significant amounts of money gambling at that exact casino.

This suggests that the bomber was motivated as much by the casino not having that money as he was in getting it for himself. Not only did he have motive to use an actual, armed bomb, but he might have also included some form of secondary, such as incendiaries, to start fires in the damaged structure and make it a total loss rather than repairable.

I'm actually kind of amused by that. All the stubborn casino owner had to do was pay the guys off and hope the cops finally caught up to them. But pride and "acting on principle" ended up costing him an extra $15M.

hindsight's a bitch, there's a reason why the US govt doesn't negotiate with terrorists and the like. Plus they had gone past the 24hr mark and so ppl had more unanswered questions.

Having said that, what were they expecting to come out of putting fake money in the bag!!! Had everything gone to plan, and the bomb was real, the result would have been the same!

If you pay the Danegeld, you will never be rid of the Dane.

So he lost alot of money, that's motive for getting it back. I can't see the link from 'i want my money back' to 'i'm going to blow you to smithereens'. If the plan had worked out, it wouldn't have mattered real or fake, he'd have his $3M. And it'll take alot less time, less risk of accidental detonation and be easier to implant.

Unless you're saying that he took the loss personally and there is only one part which alludes to it, where he was 'humiliated' by the hotel staff asking him to vacate the room that was reserved for him as a former high roller.

I'm not saying everything's unicorns and fairies but I didn't get the motivation to cause actual harm and therefore the plan felt wasteful to me to have a real bomb. And why would he say that if 'there was a double cross, I'll come back at a later date to do it again'. That just totally ignores what he said at the beginning of the letter about not giving instructions of there was any deviations to the plan and also contradicted to the bomb being real and destined to go off anyway with a unstoppable 3rd timer.

"American Hustle" meets "Speed", coming Summer 2017 no doubt.

sigh, yet another site which needlessly doesn't work without JavaScript. It's a pity, because the article itself is great.

This ship sailed years ago. Kinda time to get over it.

The content is mostly there, it's just covered up. Using the inspector tools to delete the div with id 'loading' will reveal stuff.

I don't get it, the first time I heard this, I thought it was some big joke, but there really are ppl with js turned off? In 2015? Don't you need it to sign into anything... like HN? Or post a comment.

Precisely, because it is 2015, people like me have turned off js and enable it selectively. Why? Because of all the security implications of letting a website run whatever it wants on your computer. It also breaks some of the tracking, which is a nice bonus.

HN doesn't depend on any clientside JS.

you're right and that's pretty cool, looks like everything's statically served, simple html

Well, generated server-side at least.

The web is so much faster with JavaScript disabled. JS has become the new Flash in terms of web page performance. Is JS really needed for what is primarily text based content?

I don't know guys... spent the last 15 minutes with js turned off, github didn't work (graphs don't load), meteor/atmosphere/any single page app doesn't work, ebay didn't work, i'm not a fb fan but i'm pretty sure that wouldn't work, staticice worked, but half of the merchants on it didn't. alot of the blog sites HN links to were ok, however, comments are the gold nuggets and alot of them depends on pulling in cloud services via js.. It was kind of cool to see google work in a limited fashion...

But that's 15 minutes of my life I won't get back, and alot more if I was to start whitelisting sites (which at this rate, would be every site I visit) and wearing a tin foil on my head, just saying... (<-- light hearted joke for the too religious :)

I have it turned off in my main browser with NoScript, and then selectively turned on for sites I frequently use (like HN) with poor usability without it (like HN). It's actually surprising how many actually require it though. I prefer to use emacs-w3m, and thus not get distracted with images or anything else.

But no, JavaScript is not required to sign in (that's what HTTP Basic and Digest authentication are for), nor to post comments (that's what the HTTP POST method is for); both capabilities are available to a non-JavaScript browser.

In firefox I just went

  View > Page Style > No Style

and everything was fine

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