Neutrinos Surprise Scientists. These Particles Show How Little We Know About Reality

What matters to us is that we are able to describe the surrounding reality with complete accuracy, as we see it with our senses, able to describe the physical laws that regulate the movement and behavior of objects in space and time, when we are in a certain size level, all these laws stop working and reality turns out to be something completely different, defying logic and completely beyond our intuition?

The fact that the world on a smaller scale is governed by quantum physics rather than classical physics is disturbing. It is not known where the boundary is beyond which one physical law disappears and another appears. Moreover, despite decades of effort, scientists have not yet been able to connect these two worlds, which would allow us to describe reality with a single, coherent and unified theory.

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There are ongoing attempts to verify whether quantum phenomena can be described using physics known to everyone to describe the microscopic world. The latest research of this kind shows that there is no chance of this happening in practice. The world on the quantum scale looks completely different from the world we work in every day, although in fact these two components are components of the same world and occupy the same space.

In the latest Scientific material Published in the journal Physical Review Letters The researchers decided to look at the behavior of neutrinos using an interferometer to see how they behave when they encounter an obstacle in their path. No matter how you look at it, neutrinos are microscopic objects, but they are very large in the quantum world.

In this case, the basis for conducting experiments with an interferometer was the mathematical theory of the Leggett-Garg inequality. This theory states that a system can only be in one or another of the states available to it, and even measuring this state cannot directly affect it. As you can imagine, macroscopic systems satisfy this inequality (although I do not know, after all, it is enough to look at my dog ​​wanting to go for a walk to instantly change its state to “excited” upon observation), but quantum systems do not (here Schrödinger’s cat immediately comes to mind).

Therefore, the Leggett-Garg inequality is used to determine the state of a given object at specific points in time and the relationship of this state to the state at other points in time.

During the experiment, the scientists used a neutron interferometer, in which a beam of neutrons is emitted toward a specific target. As it travels through the interferometer, the neutron beam splits in two and reunites at its target. According to Leggett and Garg’s theory, there could be two outcomes: either the neutrons fly in one path or the other. Here, the distance between the two parts of the neutron beam was several centimeters, so it was… quite microscopic.

The scientists examined the neutron beams at different points in time using several measurement methods. As it turned out? The neutrons moved simultaneously along two separate paths, a few centimeters apart. Therefore, it turns out that they violate the Leggett-Garg uncertainty. This in turn suggests that this experiment cannot be properly described without using quantum physics. Moreover, it means that any description of reality that ignores quantum complexities will be incomplete. Physicists still have a big challenge ahead of them. If we want to fully understand and describe the reality around us, we need to find a way to combine classical and quantum physics. Otherwise, we will only be working on approximations and simplifications.