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https://www.science.org/doi/10.1126/sciadv.aaw2594

Apparently human language conveys information at around 39 bits/s. You could use a similar technique as that paper to determine the information rate of a speaker and then correct it to 39 bits/s by changing the speed of the video.


The argument I've seen against their usefulness is that they only work against static militaries that don't have NBC training, and a modern military can already defeat threats like that without paying the political cost of using them.

https://acoup.blog/2020/03/20/collections-why-dont-we-use-ch...


In addition to what the others have said, the F-35B is more properly a STOVL aircraft: Short Take Off, Vertical Landing. It can't take off vertically with a useful combat load.


My favorite anecdote about magnetic core memory comes from the development of the Naval Tactical Data System.

https://ethw.org/First-Hand:The_Naval_Tactical_Data_System_i...

A paper bag of magnetic cores disappeared while the engineers were out to lunch:

> But shortly after, the engineer called and asked if the shipment was there. This did not sound too good. With a little detective work we found a cleaning crew had worked in the office while we were gone. A little more sleuthing revealed that the bag had been accidentally knocked into a waste basket, and that load of waste had already been dumped into the plant incinerator. The incinerator ashes were spread over a concrete floor, and sure enough there were small magnetic cores, about one sixteenth of an inch in outside diameter, mixed in with the ashes. The CP-642 B had 32,768 30-bit words in its memory, meaning, with spares, there were just about one million magnetic cores in the ashes. At ten cents per core, the ashes held about one hundred thousand dollars worth of cores.

We reasoned the cores were the result of a firing process, and the heat of the incinerator probably had not hurt them. Maybe it even made them better. A quick test of some of the cores picked from the ashes revealed the cores were as good as ever. We and a contingent of Univac engineers & technicians spent a fun filled day rescuing the cores from the ashes with long needles. The cores were strung into the machine’s memory planes, and it passed all performance and environmental tests with flying colors.

That entire history is worth a read if you are interested in computer history of the military variety.


Thanks for that charming bit of history. Humorous but also astonishing that the cores were salvageable after such rude treatment. The use of such cores was before my time in the computer world so I have no experience with them. I wondered if the tiny cores could have been scooped out of the ashes by a magnet. I'm sure the engineers would have thought of it, I'm guessing that would have damaged them. (Or more likely it wasn't even possible to collect them that way...)

Threading the burnt cores onto needles would definitely not be my idea of fun. Though I imagine a needle full of them would resemble a string of beads. Come to think of it, as described those cores would make a mighty interesting necklace (and FWIW my wife thought so too).


Interesting story. By the way, the NTDS computer system you mentioned was very successful and important for military computing, but it's almost forgotten now.

Wikipedia has more info: https://en.wikipedia.org/wiki/Naval_Tactical_Data_System

The book When Computers Went to Sea: The Digitization of the United States Navy has a very detailed history.


https://physics.stackexchange.com/questions/480113/how-large...

The risk of an explosion was very real, but the show claimed it would be measured in megatons, which is completely ludicrous.


I see comments there explaining that the writer got that estimate from a phsycist, so maybe wrong, but definitely not ludicrous. Linked from that same discussion: https://old.reddit.com/r/TVChernobyl/comments/boo19f/did_she...


No it’s ludicrous.

Much of the point of the manhattan project was devising mechanisms to bring fissile materials together fast enough and precisely enough that they could reach criticality for long enough to produce an effective weapon. To propose that you could get comparable effects via nuclear materials burning through their containment vessel melted in a pool is absurd and just extraordinarily unlikely.

That quote is about “testimony” of a Soviet physicist… who knows what political or other motivations were at work to justify that statement. I can’t imagine any modern physicist saying that was reasonable and it seems the writer couldn’t make that happen… it just seems like a fishing expedition for the most impressive quote that found someone saying something ridiculous and used that as a source of truth ignoring everything else which wasn’t as “fun”.


You sure are interpolating a lot of your own angle into this discussion. Do you think most laypeople would understand (or even remember) the implications of the difference between a 100kT explosion and a 4MT one? Probably not, right? Why do you think the writer would? Is it actually an important difference as far as the narrative is concerned? You'll find that no, it isn't. Even if it were, it's pretty ridiculous to think that expert testimony from the event wouldn't be an appropriate figure to use for a dramatization of the event.


I’m really not.

The contemporary quote was either misattributed, missing context, or a straight up lie.

It’s not hard for an ordinary person to imagine what 4 million tons of explosive equivalent might be, or a hundred thousand, both are ridiculous. The actual risk was an explosion on the scale of a few buildings or a minor criticality incident which splattered melted nuclear material in a very small local area.

You’re not going to find a nuclear physicist who could back anything else up with calculations, the author tried and couldn’t.

The problem with your “viewers are ignorant so it doesn’t matter point” is that viewers aren’t totally ignorant and are then fed with very false information which makes any understanding that they did have considerably worse.


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