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Glass discs that can store 360TB and remain intact for billions of years (2016)

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Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#171

Post by nathan_long »

mapcars wrote: post #116
orbital-decay wrote: post #54

Earlier quoted context omitted.

Yeah, actual museum-grade archival is so much more than just having an aging-resistant media. You also need to be able to read and decode it many years into the future, which is really tricky to guarantee - you can't assume the future generations will know how to make a reading device and remember your formats/encodings. So it's a bit like unzip.zip problem.

>You also need to be able to read and decode it many years into the future, which is really tricky to guarantee Not really, those future people don't just come out of nowhere. It's a gradual, incremental change as there are still systems using tape storage the technology or formats are not lost but migrated.

This assumes an unbroken chain of people devoting time and resources to migrating the data. Any gap would mean that data is lost or requires much more expense to recover.

Find a 3.5" floppy disk from 1995 with WordPerfect files on it and see how much effort it takes you to get the documents back. Now imagine 100 years have passed.

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#172

Post by lvh »

sp332 wrote: post #170
lvh wrote: post #139

Earlier quoted context omitted.

Yes, 13.8Gy is the approximate age of the universe and yes the researchers used that number. But it's not like they made this up ("phony", as you put it)! Turns out the biggest decay factor is nanograting and the biggest contributing physical quantity is temperature. They plotted what decay would look like on an Arrhenius plot. They both computed estimates and measured to confirm: the measurements are quite accurate.…

13.8 Gy is the age of the universe so far, in the past. Completely irrelevant to how long the discs will last starting from now.

What would be a good number of years to use? "Literally as old as the Universe is now" seems like as close a number as you can use to put timespans that big into _some_ sort of perspective.

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#173

Post by nathan_long »

schpaencoder wrote: post #47

I still remember the promise of the CD-Rom. Billions of years.

CDs that you burned chemically with a laser at home were much less durable than those physically pressed in a factory from a glass master.

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#174

Post by lvh »

modsiw wrote: post #169
lvh wrote: post #129

Earlier quoted context omitted.

The 13.8Gy claim is made by estimating, calculating and then confirming by experiment how quickly wear and tear works (the primary mechanism is nanograting, and the primary contributing physical quantity is temperature). It then specifically grabs 13.8Gy as an example data point because that's the age of the Universe, but they could've picked any other point on a time/temperature scale, like, say, "room temperature".…

Because they first chose the result they wanted — age of universe and worked backwards to derive that result. Is it true? Sure, probably. The method flys in the face of the foundations of science and was done for sensationalism. What’s special about 462K? Is it a local min/max? Doesn’t seem so.

They computed, verified and measured wear and tear (lifespan in Gy) as a function of temperature. The paper, which I linked, includes the full plot. They had to pick _some number_ (temp or years) in order to communicate it as one data point. There's nothing special about 462K -- it's what happens when you pick the age of the Universe as how long you want it to last form now. Pick a billion years, or 10 billion, and you get a different temp.

Given that they had a hypothesis, designed an experiment and validated the result, it seems a bit much to say it "flys[sic] in the face of the foundations of science".

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#175

Post by [deleted] »

totaldude87 wrote: post #115

This keeps repeating every few years i guess. https://www.theverge.com/2016/2/16/11018018/5d-data-storage-... https://www.extremetech.com/extreme/160928-five-dimensional-... https://www.extremetech.com/extreme/92892-five-dimensional-g... or did we capture its evolution :)

[deleted]

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#176

Post by rtkwe »

Cthulhu_ wrote: post #94
toyg wrote: post #45

Seems a bit of a waste to dedicate an entire 360TB disc to a single text document like a bible, which is probably just a few KBs... /s More seriously, they don't talk about reading capabilities (retrieval speed etc). And what if it gets scratched? What is the error tolerance? At that density, a single speck of dust could have dramatic implications... I hope this reaches industrial viability, because we desperately ne…

What would IMO be a better solution is something like the pyramids - something huge, with a lot of data written down / chiseled in without any weirdness like parity bits or binary code, and a lot of redundancy. Imagine the pyramids but made out of modern materials, resistant to erosion and earthquakes. Ceramics? Silicon? Either way it'd have to be legible without the need of a microscope or computers. Write the same…

It depends on your goal, there's long term storage that assumes we'll retain the technology and knowledge required to read it (or it will be easily reproduced, ie the reader technology is trivial to produce in the future because technology has advanced really far) and then there's the civilization restart archive that assumes we'll be anywhere from cave people up to basically where we are today. Really for the second type I think both the macro scale and a micro scale (though not digitally encoded for most of it) in combination along with something like the Rosetta Disk [0] from the Long Now project is probably the way to ensure it's actually readable. The large scale text would provide a boot strap to get optics set up that could read the smaller etched text on archives that could then setup the tech to read the even finer etched stuff and so on maybe eventually reaching disks like the one in the article where we're able to store digital files and the knowledge to read them was introduced in more human readable formats.

[0] http://rosettaproject.org/disk/concept/

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#177

Post by sp332 »

lvh wrote: post #172
sp332 wrote: post #170

Earlier quoted context omitted.

13.8 Gy is the age of the universe so far, in the past. Completely irrelevant to how long the discs will last starting from now.

What would be a good number of years to use? "Literally as old as the Universe is now" seems like as close a number as you can use to put timespans that big into _some_ sort of perspective.

How about an actual estimate? If it's 100 billion years that would be an even cooler number to throw around. 7 times the age of the universe!

A more useful number would be MTBF or a decay rate.

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#178

Post by jnurmine »

oftenwrong wrote: post #97
orbital-decay wrote: post #54

Earlier quoted context omitted.

Yeah, actual museum-grade archival is so much more than just having an aging-resistant media. You also need to be able to read and decode it many years into the future, which is really tricky to guarantee - you can't assume the future generations will know how to make a reading device and remember your formats/encodings. So it's a bit like unzip.zip problem.

http://rosettaproject.org/ >For the extreme longevity version of the Rosetta database, we have selected a new high density analog storage device as an alternative to the quick obsolescence and fast material decay rate of typical digital storage systems. This technology, developed by Los Alamos Laboratories and Norsam Technologies, can be thought of as a kind of next generation microfiche. However, as an analog storag…

Wouldn't one have to encase this in a diamond shell or something to avoid scraping it?

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#179

Post by slm_HN »

dotancohen wrote: post #144
bookofjoe wrote: post #26

Earlier quoted context omitted.

"'Dragon's Egg' is a 1980 hard science fiction novel by Robert L. Forward. In the story, Dragon's Egg is a neutron star with a surface gravity 67 billion times that of Earth, and inhabited by cheela, intelligent creatures the size of a sesame seed who live, think, and develop a million times faster than humans. Most of the novel, from May to June 2050, chronicles the cheela civilization beginning with its discovery o…

I absolutely loved this book. However, isn't it curious that the humans arrive just as the cheela are reaching the level of technology needed to communicate? In terms of human time, they could have come a year earlier, or a year later.

As I remember the book it was the humans probing the neutron star with something (x-rays?) in order to survey/study the star that triggered the evolutionary advances in the cheela. So no, it wasn't curious timing, the humans precipitated the rise of the cheela.

Great book btw, hope I'm remembering it correctly.

Re: Glass discs that can store 360TB and remain intact for billions of years (2016)

#180

Post by logfromblammo »

dTal wrote: post #88
theclaw wrote: post #41

Earlier quoted context omitted.

That seems more like five degrees of freedom than five dimensions.

What's the distinction? Wikipedia seems to think there isn't one: "In mathematics, the dimension of an object is, roughly speaking, the number of degrees of freedom of a point that moves on this object." https://en.wikipedia.org/wiki/Dimension

N dimensions can give you 2^N degrees of freedom.

If you have 3 spatial dimensions x, y, z, then you can have 3 degrees of freedom by translation and scaling along those dimensions. You can also have another 3 degrees of freedom by rotation around planes x^y, x^z, and y^z. I'm not sure what degrees of freedom are represented by the dimensionless scalar and pseudoscalar x^y^z, but probably one of them is mana points, and the other is hit points.

Two spatial dimensions give you two translation/scaling axes (x, y), one rotation (x^y), and one stamina points (scalar).

A 4x4 transformation matrix has 16 values, suggesting 4 dimensions, but it doesn't have 16 degrees of freedom, because several values are constrained. Nine values have three degrees of freedom, three other values have three more, and four are fixed, with zero degrees of freedom. Those six degrees of freedom suggest three dimensions, where two of the potential degrees of freedom are ignored.

So a higher-dimensional mathematical space can embed a lower-dimensional model, if the constraints are clever enough, and map the degrees of freedom onto the right dimensions or combination of dimensions. This might be useful for generating smoother animations using linear interpolation, or avoiding gimbal lock, or attempting to unify gravitation with electronuclear forces, or something else.

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