what is quantum computer? Is it real That it can change the matter of objects?

This is a computer which makes use of the quantum states of subatomic particles to store information, follows the laws of quantum mechanics, a branch of physics that explores how the physical world works at the most fundamental levels. At this level, particles behave in strange ways, taking on more than one state at the same time, and interacting with other particles that are very far away. Quantum computing harnesses these quantum phenomena to process information in a novel and promising way.

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