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Ask a question for a Magic 8 ball, and it will answer yes, no, or something indecisive. We think of it as a child's toy, but the theoretical computer scientists use a similar tool. They often imagine that they can refer to the hypotheses called oracles that can be immediately, and accurate, answering specific questions. These magical thought experiments inspire new algorithms and help researchers map the landscape map of calculations.
The researchers call the prophet working in a sub -school of computer science called a complex theory of calculation. They are interested in the inherent difficulties of issues such as determining whether some are the main or find the shortest path between the two points in the network. Some problems are easy to solve, other problems seem much harder but there are easy -to -test solutions, while others are still easy. Quantum computer But it seems difficult for ordinary people.
Complicated theorists want to understand whether the differences are clear about difficulties. Is there something really difficult about certain issues, or we are not smart enough to offer a good solution? The researchers solved such questions by arranging problemsComplex classroomsFor example, all problems easily occur in one class, and all the easy -to -test problems occur in another group and prove the theorem of the relationships between those classes.
Unfortunately, the mapping of the landscape of the fastidious calculation has become difficult and difficult. Therefore, in the midst of the 1970s, some researchers started studying what would happen if the calculation rules were different. It was the place where the prophets came.
Like Magic 8 Balls, OraCles are immediately answered devices with or without anything about their internal activity. Unlike the Magic 8 balls, they always say yes or no, and they always have an advantage of fiction. In addition, any Oracle will only answer a specific type of question, such as this number is a prime number?
What makes these fictional devices useful to understand the real world? In short, they can reveal hidden connections between different complex layers.
Take the two most complex layers. There is a group of easy -to -solve problems, which researchers call P, and classes that are easy to check, which researchers call NP NP. Is all easy -to -test problems that are easy to solve? If so, that means NP will be equal to P, and all the encryption will be Easy to crack (Among other consequences). Complicated theorists suspect that NP is not equal to P, but they cannot prove that, although they have tried to determine the relationship between the two classes for More than 50 years.
Oracles helped them better understand what they are working. The researchers invented prophets to answer questions to solve many different problems. In a world where every computer has a hotline for one of these prophets, all easy -to -test problems will also be easy to solve and P will be equal to NP. But others, less useful, have the opposite effect. In a world created by these prophets, P and NP will vary.