Calculating Technological Regression from Global Thermonuclear War

[Anthony]

Originally Posted by Willy

Excuse me but I´m not convinced of this. Because while DVD´s and so on don´t store Info by using magnetic particles, the typical hard drive is a magnetic disc, the flash storage chips, and SSD´s use microchips. Both will suffer badly from a EMP.

A Microchip is basically constructec from very minimized electric conducting wires, the first was build using wires, only now the process is down to the nm scale, but the technique is the same. Some of the stuff gets fried if a lighning strucks a nearby building even if disconnected from the Grid. As for magnetic storage devices, thanks to earth magnetic field the tend to loose data over time, remember watching a VHS casette after years lying in the corner never used before ?

Normal levels of EMP are dangerous because wires can capture the signal and focus it on one vulnerable system; without such focusing they aren't strong enough to do all that much. As for the VHS cassette in the corner, that's thermal degradation, not the Earth's magnetic field.

[Anders]

IIRC, there was a large coronal mass ejection in the 19th century and a lot of telegraph stations caught fire.

[Willy]

Originally Posted by Anders

IIRC, there was a large coronal mass ejection in the 19th century and a lot of telegraph stations caught fire.

Originally Posted by Anthony

Normal levels of EMP are dangerous because wires can capture the signal and focus it on one vulnerable system; without such focusing they aren't strong enough to do all that much. As for the VHS cassette in the corner, that's thermal degradation, not the Earth's magnetic field.

Yes, the telegraph connection was badly damaged that time, same could happen again, according to scientists, we have been lucky that since then no such big event happened.
Theproblem is the finer the structures, the easier they are damaged, it takes a lot more for a telegraph wire to catch fire, than for a structure that´s measured in nm.


As for the VHS, sorry but I asked my Prof and some engineers, the answer was always, due to earth geomagnetic fields all data safed by magnetic means will lose over time the data stored there. By the way this casettes have been stored in the house. Away from mayor electronic equipment, and protected from moisture and direct solar radiation, just to be save. We know all the coils of magnetic tape that was once used to store electronic data, they also will suffer over time. Even if there is no earth magnetic field, the plastic used to make them will degrade, of course this can be slowed by storing them under good protection from heat, sunlight and so on. But for example the plasticizer will gas out and make them brittle.

A big problem after the bomb fell for the rebuildig effort is to get the equipment and computer programs to read the storage mediums, just remember how many old computer languages are nearly extinct now along with the people who used them, that was even in Y2K a big problem, to much computer programs to edit but never enough people who could do this. Just think that the serious rebuilding will start after a generation or two, how much knowledge can be preserved and teached by the survivors ?

There is actually a project that has as goal to preserve the human knowledge, they use another way. The storage medium is a disc of a very durable alloy, with normal eyesight you get the information in pictograms to builds a magnifying glas. With that you can read the instruction to make a microscope, with that you can read..... until you can build a computer to read the final info.

That´s a possible way to store safely knowledge for the time after doomsday, for all other people a book is a source of knowledge that neiter needs electricity nor other equipment.

[AlexanderHowl]

Yes, hemp paper is probably the best form of record keeping, as it can survive for centuries if properly stored, while most forms of magnetic storage decay within a few decades even if properly stored. Disc rot is especially annoying to those of us who remember promises of eternal storage from CDs.

[Anthony]

Originally Posted by Willy

As for the VHS, sorry but I asked my Prof and some engineers, the answer was always, due to earth geomagnetic fields all data safed by magnetic means will lose over time the data stored there.

I can't find any confirmation of that claim, and sources such as https://www.clir.org/pubs/reports/pub54/2what_wrong/ indicate that the problem is that the materials are inherently unstable.

[Willy]

Originally Posted by Anthony

I can't find any confirmation of that claim, and sources such as https://www.clir.org/pubs/reports/pub54/2what_wrong/ indicate that the problem is that the materials are inherently unstable.

After reading the article, I have to say you are right about the degration of the material.

[Tom Mazanec]

For long term knowledge preservation:
https://www.memory-of-mankind.com/
https://en.wikipedia.org/wiki/Memory_of_Mankind
Million years plus.