In classical physics, the results of measurements can be perfectly predicted, assuming complete knowledge of the system beforehand. In quantum mechanics, even if you have a complete understanding of a system, the results of certain measurements will be impossible to predict. In classical mechanics, objects exist in a specific place at a specific time. In quantum mechanics, objects exist instead in a fog of probability; they have a certain probability of being at point A, another chance of being at point B, etc.

Two physicists and a chef talk about the joys and challenges of spending the entire polar winter at the Amundsen-Scott South Pole station. Schrödinger's cat is an often misunderstood thought experiment that describes the qualms that some of the first developers of quantum mechanics had with their results. Entanglement has been shown to be one of the most essential aspects of quantum mechanics and occurs in the real world all the time. Many researchers have sought a theory of quantum gravity that would introduce gravity into quantum mechanics and explain everything from subatomic to supergalactic realms.

Quantum physics predicts these patterns, which explain the different chemical and physical properties of all elements. Quantum mechanics is a subfield of physics that describes the behavior of particles, atoms, electrons, photons and almost everything in the molecular and submolecular realms. This is known as the rise of classicality, which states that a quantum mechanical description of large objects must be the same as their classical description. Scientists call each of these discrete steps “quantum”, from the Latin word that means “how much”, and they say that the quantum properties with this ladder structure are “quantified”.

Unlike the usual formulations, this modification leads to the appearance of classicality in a thought experiment, which is problematic for standard quantum mechanics. Other researchers have also worked on theories related to loop quantum gravity (opens in a new tab), in which both time and space are presented in discrete, tiny fragments, but so far no idea has managed to gain a significant foothold in the physics community. Although the Stern-Gerlach experiment with macroscopic particles is purely theoretical, the team believes that in the near future it will be possible to carry out a real empirical study using particles heavy enough to expect them to behave classically. According to Bohr's interpretation of quantum mechanics, until the box was opened, the cat existed in the impossible dual position of being alive and dead at the same time.

So while NASA can accurately track the trajectory of an ordinary spacecraft on its journey, it wouldn't have so much luck with a quantum ship. Developed during the first half of the 20th century, the results of quantum mechanics are often extremely strange and contradictory. While in Penrose's approach to quantum physics, classical behavior emerges when expected, it has flaws.