Quantum computing: a subversive paradigm revolution
Quantum calculations, the word has been on fire for a long time in the world of technology, but many people may still understand it in the vague impression that it is “many times faster than a supercomputer”. As a long-standing practitioner of cutting-edge technology, i have witnessed its evolution from the inexplicable theory of laboratories to engineering exploration. Today, instead of talking about the grand narratives, we start with the most fundamental principles, talking about what quantum calculations are, what they are about to bring about subversion, where we are now, and where they are most likely to bloom in the future. Whether you're a curious lover or a developer in related fields, this article will take you through the fog and see a clearer quantum calculation view。
In short, quantum computing is a new mode of calculation that uses quantum mechanics (e. G. Superimposed and tangled) to process information. It does not replace the laptop you have in your hand to process documents or play games, but it targets specific complex issues that classic computers (all of which we use now) are almost impossible to solve, such as simulation of molecular structures, optimization of mass logistics routes, cracking of existing encryption systems. It's like being invented not to substitute bicycles for commuting in a district, but to complete cross-continental travel, which solves problems of completely different scales。
2. Decomposition of core principles: fundamental differences between bits and quantum bits
To understand the power of quantum computation, it must start with the basic unit of information. That is the starting point of all confusion and the source of all possibilities。
2. 1 classic bits: the world of certainty
Our familiar classic computer, whose information is processed on the basis of "bit". A bit is like a little switch, and at any given time it can only be in one of two certain states: a switch or a switch, as we say in 0 and 1. All text, pictures, videos, at the bottom of the computer, are encoded into an ultra-long series of 0 and 1. The computing process of a classic computer is essentially a high-speed reversal of the state of the switches in accordance with established rules (calculations)。
This “non-zero or one” characteristic is determinative. A bit's state at a given moment is the only one that can be accurately measured. This brevity has led to the modern information society, but also to fundamental constraints: when the problem complexity index scale increases, the number of possibilities that classic computers need to be enumerated increases explosively, making the calculation time unacceptable。
2. 2 quantum bits: also overlapping and entanglement
Quantum bits are the basic unit of quantum computing, and their core properties are derived directly from quantum mechanics, completely breaking the classic bits framework。
First of all, there is a "scramble." a quantum bit can be placed in a mixture of > and >1 at the same time. It's not "between zero and one," but it's between zero and one, just like when a coin spins at high speed, you can't say whether it's positive or negative, but it's both possible. We describe it as a state vector: = = | > > > β β β β β β > > . Here, alpha and beta are complex numbers, called probabilities bands, that meet the |alpha 2 + βbeta 2 = 1. When we go to measure the quantum bits, it collapses to zero with the probability of thaium-2 and to one with the probability of thaium-2. Before measurement, it carries two possibilities。
Note: the superb state is not a simple "probability mix". Probability mixing means that the system is already in a certain state, but we don't know. The superimposed state, which is the relevant combination of the system itself in all possible states, is the source of parallel computing capability。
Next is the entanglement. This is one of the most mysterious and powerful features of quantum mechanics. When two or more quantum bits are entangled, their state is interconnected and cannot be described separately. For example, the entanglement of a double quantum bitt (belt) can be expressed as (0000+|11)/√2. This means that once we measure the first quantum bit, the second quantum bit collapses to zero, no matter how far apart; if the first gets one, the second must be one. They act like a whole。
Twisting
