The word uncertainty is used a lot in quantum mechanics. One school of thought is that this means there’s something out there in the world that we are uncertain about. But most physicists believe nature itself is uncertain.
Quantum simulation gives a sneak peek into the possibilities of time reversal. An international team of scientists led by Argonne explored the concept of reversing time in a first-of-its-kind experiment, managing to return a computer briefly to the past. The results present new possibilities for quantum computer program testing and error correction.
One of the underlying principles of quantum theory is that quantum objects can exist as waves or particles. But, they do not exist as either until they are measured, making it seemingly unachievable to identify or track quantum objects when they’re not being observed. But recently, physicists faced this issue and proved that it is not an impossibility to track unobserved quantum particles.
In the world of quantum, infinitesimally small particles, weird and often logic-defying behaviors abound. Perhaps the strangest of these is the idea of superposition, in which objects can exist simultaneously in two or more seemingly counterintuitive states. For example, according to the laws of quantum mechanics, electrons may spin both clockwise and counter-clockwise, or be both at rest and excited, at the same time.