Nature reports on an experiment in which atoms were trapped between laser beams and changed their spins at the same time. If it were possible to separate them, it would be possible to use a method for quantum computing
Physicists at the American Standards Institute succeeded in driving thousands of atoms trapped between laser beams to exchange spins with their partners simultaneously. The repeated exchange, similar to a quantum version of swapping partners in a dance hall, but lasting only 10 milliseconds, may one day allow logical operations to be stored in quantum computers, which theoretically could quickly solve certain problems that today take the best supercomputers years, if at all. to solve.
In a press release from the Standards Institute, it was stated that the dance of the atoms, which was reported in the July 26 issue of the journal Nature, demonstrates advanced aspects of using neutral atoms as quantum bits (qubits) for storing and processing data in quantum computers. Thanks to the strange properties of quantum mechanics, the rule book used by the tiny particles of matter and light, quantum computers could provide enormous power for applications such as cracking today's most complicated ciphers. Neutral atoms are among the dozen or so systems now being tested worldwide as candidates for storing qubits; Their weak interaction with the environment may help reduce calculation errors.
It will be possible to perform the equivalent of multiple classical calculations simultaneously in the quantum world" says Trey Porto, a researcher at the American Standards Institute (NIST) whose research is published in the journal Nature. Forto and his colleagues "convinced" a pair of rhodium atoms cooled to an extremely low temperature, to exchange places between them alternately, a feature that could be used to store and process data in quantum computers.
In today's computers, the smallest unit of information is the digit or bit (we used to call it a bit), which can contain only one of two values - zero or one. These bits form the basis of the data storage system in the digital computer. When the bits are combined into a group of eight on a typical personal computer, these bits become a byte (or bytes). In the quantum world, instead of only two possibilities - zero or one, it is possible to reach a wide range of possibilities". Porto said.
As mentioned, this is a preliminary experiment because there is no point in thousands of atoms being used as qubits at the same time, and the idea is that it will be possible to control each pair of atoms.
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Of course I did talk about speed (ie complexity): not about "what" can be calculated but about "how fast" it can be calculated.
For 3 and others: the belief is that a quantum computer will not solve NP-complete problems. That is, the belief is that it will not solve every problem in NP, but only certain problems in NP like Pictor and his family members. And by the way - there is a relatively simple example that illustrates the exponential advantage and the algorithm is called "Simon's algorithm".
To Daniel - if they increased the financial investment by two or three orders of magnitude (let's say $50 or $500 billion), would there be a giant quantum computer that crunches large numbers within two years? In my opinion no, because the realization that is promising enough has not yet been found, and many different directions are being explored.
So it's too early to bet how long it will take.
Tal:
It seems to me that the debate between you and Jacob (9) is about terminology.
If I understand Jacob's intention correctly - he includes in the term "computational" the problems that, in principle, given enough time, a computer can solve and he emphasizes the difference between computational and speed. You are tying the two terms together.
Essentially, I think you agree.
Several comments/clarifications:
To 7: Quantum encryption solves some of the goals of encryption, but not all. Also, there are still no safety proofs for the equipment that is being sold, and even when there will be safety proofs - the safety will probably not be perfect when the distance increases beyond some threshold. In conclusion, the day a quantum computer cracks RSA practically, the world will no longer be the same as it is today. But - this day is still very far away.
For 9: A quantum computer solves certain problems exponentially faster, so it is definitely stronger from a computational point of view (that is, in terms of calculation power), but what - it has not yet been proven that RSA is difficult on a normal computer, so it is possible that it will be broken much earlier.
A quantum computer is not computationally more powerful than a computer of today. Both have the same computational power, except that in a quantum computer it is possible to do MULTI-CHECKING of options (through superposition), instead of going through them serially.
A phenomenal leap in speed (problems of billions of years, all NPC problems when N is high enough) will be able to solve in minutes.
But not at all a leap forward in terms of calculation. It's just a matter of time.
Dr. Shukshuk …………..not so true.
Don't underestimate yourself.
Look at GHOST IN THE SHELL STAND ALONE COMPLEX the series not the movie for example.
Computers are for our benefit and will only help us.
But we will always be the center. (whether physical or virtual)
Cracking RSA encryption is currently the killer application of the quantum computer, but it has lost a lot of its appeal because a strong encryption for a quantum computer has already been developed, it is the quantum encryption that already exists and is commercial (there are links on Wikipedia).
If it turns out that a quantum computer solves problems in NP, it will be a real revolution and within two years there will already be a commercial quantum computer.
In fact, this is really a breakthrough that will make many human jobs redundant and bring the grim vision of Dr. shake
The day is not far off when we will be redundant - put an excess on the backs of the computers whose role will be to maintain us and our lives
It's not base 4 instead of base 2, it's fundamentally different - a quantum computer model is stronger than a Turing machine model.
It is not clear whether there are algorithms for the NP problem that can be solved by such a machine in polynomial time, but there are known algorithms fast enough to crack RSA by such a computer.
Their principle is different.
Base 4 QBIT instead of binary.
It will take time to solve problems but much less time 😉
Will they be able to solve NP-complete problems?
If so, in what way?
Much faster 😀
The computing powers of such computers are powers that do not exist today.
That would be a leap forward.
What will the world look like with such computers?