As far as we know, the whole universe is just a finite state machine (see, for example, Computational Capacity of the Universe). Infinite entropy for finite systems was the big problem with 19th century physics that the introduction of quantum mechanics fixed.
Archivists make a mistake when they focus on the preservation of digital media instead of the preservation of the bits. Since bits can be copied over and over without degradation, they are potentially immortal. Academic disk-based storage systems like Oceanstore http://oceanstore.cs.berkeley.edu/ and commercial systems such as Centera and Permeon http://www.computerbanter.com/showthread.php?t=309 50 keep the bits safe using redundancy on multiple servers, geographic distribution, and continuous and automatic migration to new hardware. Just as in biology, the organism (storage cluster) lives much longer than the individual cells (servers).
Exactly the right question! With 100 electron spins you can store the first 100 bits of the library of congress. No more.
There may be some extra computations you could do with quantum bits, but there are only 2^100 distinct states ("mutually orthogonal states" in QM-speak). That means that if you want to be able to get the data back out, you can only store 100 bits.
Quantum communication is already practical, and provides a secure way to communicate to replace factoring-based encryption, which quantum computation may one day make insecure.
The hype in this article, though, is way over the top. 100 electron spins can only encode 100 classical bits. Not one bit extra. Yablonovitch is using a very sloppy way of talking about how hard it is to simulate 100 spins, and making it sound like he's talking about a way to store a lot of classical bits! His "implicit information storage" is nonsense.
It's also worth mentioning that quantum computation is unlikely to speed up any computation you care about, unless you like to simulate quantum systems. Fast factoring is the "killer app" that got people excited about this field, but "terrorists" (and the rest of us) can just stop using factoring-based encryption.
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As far as we know, the whole universe is just a finite state machine (see, for example, Computational Capacity of the Universe). Infinite entropy for finite systems was the big problem with 19th century physics that the introduction of quantum mechanics fixed.
Archivists make a mistake when they focus on the preservation of digital media instead of the preservation of the bits. Since bits can be copied over and over without degradation, they are potentially immortal. Academic disk-based storage systems like Oceanstore http://oceanstore.cs.berkeley.edu/ and commercial systems such as Centera and Permeon http://www.computerbanter.com/showthread.php?t=309 50 keep the bits safe using redundancy on multiple servers, geographic distribution, and continuous and automatic migration to new hardware. Just as in biology, the organism (storage cluster) lives much longer than the individual cells (servers).
There may be some extra computations you could do with quantum bits, but there are only 2^100 distinct states ("mutually orthogonal states" in QM-speak). That means that if you want to be able to get the data back out, you can only store 100 bits.
Quantum communication is already practical, and provides a secure way to communicate to replace factoring-based encryption, which quantum computation may one day make insecure. The hype in this article, though, is way over the top. 100 electron spins can only encode 100 classical bits. Not one bit extra. Yablonovitch is using a very sloppy way of talking about how hard it is to simulate 100 spins, and making it sound like he's talking about a way to store a lot of classical bits! His "implicit information storage" is nonsense. It's also worth mentioning that quantum computation is unlikely to speed up any computation you care about, unless you like to simulate quantum systems. Fast factoring is the "killer app" that got people excited about this field, but "terrorists" (and the rest of us) can just stop using factoring-based encryption.