From my last two blog posts on Hawking radiation and the conservation of quantum information, it’s clear that we have a major problem on our hands—the information paradox. We know that black holes decay over unimaginable timescales, seemingly erasing quantum information in the process. But we also know that quantum information has to be conserved. Theoretically, at least, we have to be able to trace particles back through their quantum histories. If black holes were entirely stable, then we could consider this condition met. While the information in a black hole would be inaccessible, it wouldn’t be destroyed. But if…
Comments closedMonth: September 2020
Have you ever thought about what happens to all the information you delete from your computer’s hard drive? You might be surprised to discover that deleted files aren’t actually erased. Even when you delete a file from your computer’s trash folder, your computer holds onto the file while erasing the file name and its listing in any directories. The file itself remains on your hard drive, functionally irretrievable (without special software) until it is overwritten when the hard drive needs that data space. At that point, your data is actually irretrievable. That portion of the hard drive’s disk space has…
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In last week’s post on entropy, I blithely referred to black holes as spontaneously increasing in entropy. This may seem counterintuitive (as much as anybody can have “intuition” about black holes). If we view the increase in entropy as a system moving from order to disorder, how would a singularity become more disordered? How could the contents of a black hole spread out in a more disordered manner if they are supposed to take up an infinitely small amount of space? If we use the other definition of entropy, the dispersal of energy, then that would imply that a black…
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What does your bedroom, the polar ice caps, and a black hole have in common? All of these objects are consistently and spontaneously increasing in disorder; they are moving towards maximum entropy. Entropy, in its simplest definition, represents the amount of disorder present in a particular system. The disorder of a system tends to increase unless energy is expended to order it again. The easiest way to imagine this is in your bedroom. Even after you’ve cleaned and organized your bedroom, over time, it becomes disorganized and messy again. The only way to return your room to its original organized…
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