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How Heavy Is a Petabyte?
Jon Morgan writes "Whilst heaving around numerous data storage systems to sell (they weigh A LOT!), we got to wondering: How heavy is a Petabyte of data storage? Our best guess is 365KG, which is 6 million times lighter than in 1980! But is there a lighter way to store a Petabyte?"
How heavy is a Library of Congress?
What doesn't kill you only delays the inevitable
What are these Petabytes of which you speak? America measures data in units of Libraries of Congress.
...weighs something like 300mg/card. That's 48GB/gram, or a bit over 20g/TB, or 20Kg/PB.
Just stick the petabyte on the cloud! Clouds are as light as air!
(why yes, I am from Marketing, why do you ask?)
Nobody knows exactly how much data the average human brain can hold, but one estimate is 500 to 1000 TB. If the average adult human brain weighs about 1.3 or 1.4 Kilos, then "about 2 Kilos" would hold 1 Petabyte.
Sure. Store it in a WOM chip. They only weigh a few grams, hold literally unlimited data, and are really fast.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
They probably want an error rate lower than 10%.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
Are you storing mostly 1s or mostly 0s? Everybody knows they don't weigh the same.
As of 10/06/03, I hate COBOL developers.
Or you could just stick a mirror "out there". The light would quite conveniently come back at you. Or you could sneak around the other side of the universe and wait for the light...
and a lot bulkier than...
a few strands of DNA.
Good judgement comes from experience, and experience comes from bad judgement.
- W. Wriston, former Citibank CEO
Oh, and BTW, when a person dies does the body weigh a tiny amount less after the sole leaves?
Depends on the shoe they are wearing. On a boot, no, its a large amount, on sneakers, yes it might be a tiny amount.
Taxation is legalized theft, no more, no less.
A common misconception, and just saying it on Slashdot doesn't make it true. Clouds weigh more than elephants - much more. In fact, you can learn the weight of clouds in elephant units here.
Not only that, but clouds are usually darker than the air around them.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
This subject has already been discussed.
I don't think there is a storage media with higher density available commercially right now - and probably not until the 64GB microsd cards becomes available.
For example, it seems to me like a "full" drive seems to physically weigh more than a blank one, sort of like a full battery is noticeably heavier than an empty one.
Wrong on both counts. A "full" magnetic hard drive platter just has its magnetic domains aligned in a certain pattern.
Those domains are physically there whether they are used for data storage or not. So the weight will be indentical.
A battery does indeed become lighter when "emptied" - according to E = mc^2 and the energy that came out of it.
However, this is way, way, way under anything you would be able to notice.
An AA alkaline battery can deliver about 10000 Joules (http://www.allaboutbatteries.com/Energy-tables.html) - so
a discharged (= "empty") AA alkaline will weigh m = E/c^2 or roughly 10^-10 grams less than a charged one.
That's 0.1 nanograms. About 100 human skin cells. No, you won't notice that.
Insightful? Assuming you can perfectly remember 1 byte per second, you'd be memorizing for over 100 million years. The human brain is great and all that, but no way are you going to store that much data while being able to reproduce it later.
That was my dissertation topic, conventional systems require ~kT per bit (k is the Boltzmann constant = 1.3806503 Ã-- 10-23 m2 kg s-2 K-1 and T is the temperature of the gate in Kelvin) for each read. Quantum systems can access well below that by various trickery (single photon optical computers can reduce this by a thousandfold). In theory a individual photon can hold huge amounts of data in it's state vector before collapse. The trick is making a measurement on enough of these photons to extract the info you need while overcoming shot noise.
and all of this sits upon a tortoise? Amazing!
But you are converting mass into energy and energy into mass even in this case, although the amounts are ridiculously small in the case of chemical reactions, which is why conservation of mass is a more than reasonable approximation in chemistry. The mass is stored in the molecular binding energy of the battery's chemicals, and converted into the energy used when the battery discharges. For example, if you weighed very very carefully a bunch of hydrogen gas, a bunch of oxygen gas, and the water you got after combining the two (in a fuel cell reaction, which we can think of as the simplest sort of battery from a chemistry point of view), the water would weigh ever slightly less than the hydrogen and the oxygen, though the difference would be extremely small, since the binding energy difference of a water molecule versus that of hydrogen and oxygen molecules is only a few tens of electron volts, about 10^-35 kg or thereabouts, which amounts to a difference of about a quadrillionth of a gram for one mole of water. For nuclear reactions though, the binding energies we deal with are millions of times greater, and E=mc^2 is much more obvious. For instance, in the nuclear fusion of the two helium-3 nuclei to produce one helium-4 and two free protons, the helium-4 and the two protons weigh less than the original helium-3 nuclei by about 12.86 MeV/c^2, or about 6 milligrams less than if we started with a mole of helium-3 at the beginning of the fusion reaction.
Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
No, not just one. It's tortoises all the way down, young man.
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