2023-04-29 20:00:00
Did you know that your shoes never really touch the ground? Or that you never get to touch another person’s skin when you caress it? Well, that’s right, and it’s all the fault of the electrons.
126 years ago, on April 30, 1897, to be precise, in his Cavendish laboratory, part of the University of Cambridge, the physicist Joseph John Thomson revolutionized the scientific world, opening the way, for the first time, to particle physics.
Lise Meitner, the scientist who split the atom
In an experiment with so-called cathode rays, discovered the electron, the negatively charged elementary particle (he called it a corpuscle at the time). In addition, he was able to establish that this new particle had a charge and a mass much lower than that of the hydrogen atom, the lightest known at that time.
Until the time of this discovery, it was thought that the atom was indivisible and the existence of smaller elements that formed it was not conceivable. For this reason, despite Thomson’s reputation and populism as a scientist, his finding was hard to believe at first.
However, it was soon established as a fact that has been shaping matter, helping to understand most of its properties to this day. However, they still exist certain unknowns around him.
THE DISCOVERY: CATHODE RAYS
To carry out his finding, Thomson used a vacuum lamp, that is, a tube where he made a vacuum inside. He endowed one end with a positive electrode, an anode, and the other with a negative electrode, a cathode, so that current began to flow between them, giving rise to electron beams known as cathode rays. Of course, at that time, Thomson was unaware that it was only about electrons and assumed that rays were atoms, simple and indivisible.
To visualize them, he provided the end of the tube with a fluorescent screen that allowed him to be aware of the point where the rays “crashed” against the end and calmly observed that the line of particles was straight. However, to his surprise, he discovered that by placing a magnet on both sides of the tube, the point where the rays arrived went up or down depending on the placement of the poles of the magnet, that is, the rays were curved. When Thomson placed the negative pole at the bottom, the rays curved upwards, while if he placed it at the top, the rays curved upwards.
The only explanation for this phenomenon was that these rays were not neutral atoms, as he thought, but some kind of negatively charged particles that were bent due to the repulsion with the pole of the same charge. From this point on, Thomson’s experiments continued. He discovered that if he placed blades in front of the rays, they would move, which meant that these new particles they had dough. Likewise, he saw that by modifying the vacuum inside the tube, and filling it with any gas, the nature of the particles did not change, turning them into universal particles.
The Irish physicist George Johnstone Stoney proposed to baptize these new particles with the name of electronsunder the assumption that they were elementary particles of electricity or, as we know them today, fundamental electrical charges.
FUNDAMENTAL BUT YET UNKNOWN
Subsequent studies allowed us to continue discovering new properties of these particles and to characterize them as much as possible. So, today, it is known that they are particles that form atoms, providing a negative charge, and that they are located in its outermost partplaced in different layers (as if it were an electronic cloud) and being able to promote from one to another by absorbing or emitting energy.
Most of the properties of electrons are known and understood by the scientific community, but there are still many that remain a mystery. For example, the operation of all its possible interactions is known and understood: the gravitational one due to its mass, the electromagnetic one due to its charge, and the weak interaction due to its subatomic nature. However, there is still no explanation for the magnitude of its mass, nor for the value of its electric charge: the electron is 2,000 times lighter than the proton although it has the same charge but in negative, and nobody knows what the explanation is.
ELECTRONS: THE BIG RESPONSIBLE
The electrons give shape to the atoms and fill their outermost layer, for which reason, since the atoms are the particles that form the matter, the electrons become the great responsible for all interaction properties Between her. That is, every time an atom is close to another, either within the same object, or by two different ones that come together, the electrons play the main role. The simplest example are colors.
It is known that those responsible for giving color to objects are photons: their vibration frequency determines one or the other tones within the color spectrum. When the photons reach the objects, there are some that are absorbed and others that are reflected, being the set of all these reflected those that provide the color we see an object. But, did you know that electrons are responsible for determining which photons are absorbed and which are reflected?
Isaac Newton, the first to explain the nature of colors
In order to pass from one layer to another in the atom’s shell, the electrons need to absorb energy that allows them to make that jump. When the photon arrives, the electron will be able to absorb those with the right energy to make your jump and get excited to a higher layer. The non-absorbed are reflected, giving the object the color that reaches the eyes of the observer.
NOTHING TOUCH NOTHING
Perhaps one of the most curious consequences of the existence of electrons is that, really, nothing is in contact with anything. That is to say, since all the electrons are negatively charged, that is, with the same charge, they feel repulsion between them, so that a great force is needed to bring them closer, making it impossible to reach a certain contact. Therefore, really, no object ever comes into contact with anothersince the electrons of its outermost parts repel each other.
Does this mean that the shoes never really touch the ground? Or that your hand never gets to rest on a table or touch another person’s skin when you caress it? That’s how it is. At all times, the repulsive force between the electrons will avoid that the atoms that make up your skin, shoes, soil, surfaces, substances… come into contact. The sensation of contact then comes from a simple chain reaction: the electrons feel the repulsive force, they are pushed back, pushing the set of atoms they form, and with it your skin, which provides the sensation of coming into contact. .
This is also the reason that would explain why a person walks through walls it becomes practically impossible: the electrons of the external atoms of the wall would interact with the external ones of your own body, preventing, due to that force of repulsion, that it merges with that of the surface, no matter how much force you use. In fact, not only would you not go through it, but you would never touch it.
Although it is true that there is a small gap in that last theory. Indeed, quantum mechanics holds that there is indeed a small chance that a human being could walk through a wall, due to the tunnel effect. Even so, the probability is one in a sextillion, that is, a zero followed by 35 decimal zeros: something so small and improbable that it is not considered feasible that it could happen.
#particle #responsible #touching