
How to store data for a billion years - robg
http://www.economist.com/sciencetechnology/tm/displayStory.cfm?story_id=13853129&source=hptextfeature
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trjordan
> To switch spontaneously from a “1” to a “0” would entail the particle moving
> some 200 nanometres along the tube using thermal energy. At room
> temperature, the odds of that happening are once in a billion years.

So, if you stored a GiB of data, that puts the lifetime of that data at ... 1
year? That honestly doesn't seem very good!

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iclelland
That's pretty much what I was thinking, reading this. First off, a frequency
measurement -- "once in a billion years", 3.16887646 × 10^-17 hertz (thank
you, Google calculator) can't really be used as a probability, as they are
trying to do.

Then, even if you assign that nonsense statement some sort of charitable
reading, like "one bit has a 50% chance of spontaneously changing state over a
one billion year period", and infer that every bit has a 1/10^9 chance of
flipping every year, then the odds that 8×10^9 bits do not change at all over
the course of a year are (1-10^-9)^(8×10^9), or about 0.034%.

Granted, it'll still take a long time for that whole gigabyte of data to be
completely scrambled, but I think we'll still be using error correction and
occasional refresh, even with a technology this reliable.

~~~
3pt14159
If you do a Raid 6 Array and manage to keep power to the storage devices you
could fix the lost bits whenever they came up. Or you could just write to 10
drives at once. The odds might be that the whole does not change 0.034% of the
time for one drive, but for 10 it would be > 99%.

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akie
You also need to build a machine that is able to read it in one billion years
time. Anyone in the room that is still able to read a laserdisc? Didn't think
so.

So, storing the information is one thing - being able to read it is a
completely different beast. If you would really want to store something for a
few thousand years, you're probably better off chiseling it in stone. Then you
only have to make sure people (or aliens?) can read our letters and understand
our words.

~~~
pavel_lishin
Well, so long as you clearly mark something as being a store of data, a
sufficiently advanced civilization would be able to figure things out.

You could even place some dummy data before the main store, with redundant
storage in another format - if you read ("decode") the data and it matches
(like you suggest) something carved in a block of stone surrounding it, you
know you have the process down, and you can go on and decode the main store.

~~~
akie
Agreed. You would probably have to start by explaining that there's important
data, and that it is stored at a nanoscale. Then you would have to proceed to
explain how they might get access to that data.

But that's not the whole of it. Once they can read the 0's and 1's, you need
to tell them how to interpret them. So you need to provide (at least) an ASCII
table in some extremely durable material.

The rest of the information (on how to interpret the data) can then be stored
in the first mega/gigabytes of the binary data. Plain text ASCII only,
ofcourse. No pictures, audio, or video. You could only include such data once
you've told them how to build a computer and all necessary software.

I think you're better off storing a computer and a self-sufficient powersource
in a vacuum, virtually indestructible structure. Has the added benefit that
you can make cool movies about it :)

~~~
tophat02
>The rest of the information (on how to interpret the data) can then be stored
in the first mega/gigabytes of the binary data. Plain text ASCII only,
ofcourse. No pictures, audio, or video. You could only include such data once
you've told them how to build a computer and all necessary software.

That's OK. At these data density scales, a small room full of 10"x10" tablets
would provide space for a LOT.

I'd imagine you'd encode media in some simple lossless RLE format which you
would then describe.

Imagine being an architect in the year 27,000 coming across this stuff. I'm
sure the value would be immeasurable, especially the video and audio! Can you
imagine having HD "documentaries" from Ancient Egypt or Greece? How cool would
that be!

As you can see, this stuff fascinates me.

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Tichy
Now where to find those nanotubes that previous civilizations left behind for
us?

~~~
bemmu
I think you just figured out what those easter island statues are for.

~~~
psygnisfive
Not to be a dick or anything, but we know precisely what the moai on Easter
Island were for. They were religious figures of the Easter Islanders. They
grew increasing large and numerous as the tribes of Easter Island began
warring with one another, in an attempt to display the "greatness" of each
tribes respective leaders. It is in part due to the obsession with symbolic
greatness and the construction of the moai that led to the eventual downfall
of the Easter Island culture, as can be seen by the eventual grass-roots moai
destruction activity during the proper collapse of the island's society in the
1700s and 1800s. The few Easter Islanders that survived the end of their
civilization described this back when they were first contacted.

Easter Island isn't some big mystery, unless you don't read history books.

</pedantry>

~~~
dhs
Whats pedantry to some is quite an interesting aside for others. Thank you,
and keep it up :-)

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kqr2
I recall reading a science fiction novel where there were some proposals to
store data for a long time.

Assuming sufficiently advanced technology, you could turn a seismically stable
rocky planet into data storage by encoding data with valleys and mountains.

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edrtfgdr
Simply encode your data into the the digits of pi and then create your own
universe with this value - that's what I did!

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TrevorJ
I wonder if you could stored data for that long by encoding it into some junk
DNA?

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lacker
Junk DNA actually changes a whole lot because there's little or no
evolutionary downside to mutations there.

~~~
TrevorJ
That's a good point. I had assumed that since There's no evolutionary pressure
it wouldn't be forced into changing as much as active DNA is. You could encode
it to multiple areas that must be checked against each other.

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lispm
Now we only need some data that somebody in a billion years wants to read.

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edw519
This reminds me of the story of the traveller who was required to take all
human knowledge to a distant planet carrying only one steel rod.

His solution?

Take everything ever written and convert in to binary. String it all together
into a very very long string. Put a decimal point in front of this string.
Then put a notch on the steel rod exactly that decimal's distance from the
bottom.

I imagine they'd need some pretty precise measuring equipment on the other
planet.

~~~
anamax
He'd need two marks. The other one is to tell you how to interpret the first,
that is, the definition of 1.0.

Also, unless he was using a very long rod, he'd have to mark somewhere in the
middle of an atom.

I think that issues like this are part of why length is now defined in terms
of wavelengths of light. And even then, the number of digits that we use in
the definition is relatively small.

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piramida
and I thought platinum pins for 1s and holes for 0s melted into solid granite
bed is the preferred long time storage!

~~~
billswift
Much better for very long term storage. The method described is actually for
extremely dense storage; the time period is pretty much bogus journalistic
stuff.

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bhousel
basically a nanotube abacus... very cool..

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a2tech
This is fascinating stuff-I believe if the human race can stop from utterly
destroying itself we're on the brink of coming up with some truly spectacular
advances in the next 50 years.

~~~
ars
We are less likely to destroy ourself now than at any other point of time in
history.

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silentOpen
Why do you say that? After humans spread across the globe in hunter-gatherer
societies, we were pretty unlikely to destroy ourselves.

Today we could easily destroy ourselves with nuclear war. It may not be likely
but it's more likely than in prehistory.

~~~
ars
Life in those days was very precarious. One bad drought and everyone would
have been dead.

A nuclear war is not likely to kill everyone. Plus a nuclear war is not likely
these days anyway.

The chance of a nuclear war today is far far lower than some disease in the
middle ages, or a drought in pre-history.

Everyone focuses on nuclear weapons, but reality is they are very very
unlikely to ever be used, plus illness is a much more severe danger. And the
good thing about today is that we are much better prepared to handle a disease
than at any other time in history.

And that's why we are less likely to destroy ourself now than at any other
time.

