{"id":384,"date":"2020-09-18T12:00:00","date_gmt":"2020-09-18T16:00:00","guid":{"rendered":"https:\/\/anyonecanscience.com\/?p=384"},"modified":"2020-09-17T20:30:27","modified_gmt":"2020-09-18T00:30:27","slug":"ctrl-alt-del-part-1-the-destruction-of-quantum-information","status":"publish","type":"post","link":"https:\/\/anyonecanscience.com\/index.php\/2020\/09\/18\/ctrl-alt-del-part-1-the-destruction-of-quantum-information\/","title":{"rendered":"Ctrl+Alt+Del: Part 1\u2014The Destruction of Quantum Information"},"content":{"rendered":"\n

Have you ever thought about what happens to all the information you delete from your computer\u2019s hard drive? You might be surprised to discover that deleted files aren\u2019t actually erased<\/a>. Even when you delete a file from your computer\u2019s 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\u2019s disk space has been completely reconfigured to serve the new file\u2019s needs. But what does this mean in terms of the file\u2019s information? We obviously can\u2019t access that information, but does that mean that the information is lost from the universe completely? <\/p>\n\n\n\n

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“Hard Drive”<\/a>\u00a0by\u00a0wwarby<\/a>\u00a0is licensed under\u00a0CC BY 2.0<\/a><\/figcaption><\/figure><\/div>\n\n\n\n

If you\u2019re wondering what this line of questioning has to do with black holes, then let\u2019s ask a slightly different question: what happens to all the information that falls into a black hole? It might be tempting to assume that all this information is simply held inside the black hole. Like our deleted file, the information isn\u2019t deleted from the universe, it\u2019s simply functionally irretrievable. Unfortunately, the discovery of Hawking radiation<\/a>\u2014the slow evaporation of black holes through virtual particle radiation\u2014completely blew this assumption out of the water and introduced the information paradox. One of the tenets of quantum physics is that quantum information cannot truly be destroyed, only transformed. But if a black hole consumes all the quantum information in a piece of matter and spits it back out as indecipherable radiation, then isn\u2019t that information destroyed? The information paradox has been a central problem for theoretical physicists for the past 50 years, and it still has no satisfactory solution.<\/p>\n\n\n\n

We\u2019ve already established that falling into a black hole<\/a> means nearly certain death for you, and all your molecules and atoms, but what about your quantum information? Just like a file, you are made up of information\u2014a set of quantum 1\u2019s and 0\u2019s that encode the past, present, and future states of every atom in your body. If we had perfect knowledge of the universe, we could track each of the particles in your body from the beginning of time to now. Information can\u2019t be lost, because we can always track a particle\u2019s present quantum state back to its past quantum state. Of course, we don\u2019t have perfect knowledge of the universe so we can\u2019t access most of this information. Like our deleted hard drive files, the information exists, but it is unindexed and only accessible with special tools. <\/p>\n\n\n