Nobel Prize for physics 2025
Ole Eriksson, head of the Nobel Committee for Physics, says:
"“It is wonderful to be able to celebrate the way that century-old quantum mechanics continually offers new surprises. It is also enormously useful, as quantum mechanics is the foundation of all digital technology,” To understand this seemingly difficult and mentally challenging subject, let's take a look at its historical development.
It is worth mentioning that the process of quantum tunneling was discovered long ago at the microscopic level, that is, at the level of atomic particles. Its historical details will be explained later, which are necessary for understanding quantum tunneling. This year's Nobel Prize was awarded for demonstrating the same quantum tunneling at a higher level, such as between two conductors in a computer chip, and proving that the natural process that occurs at the microscopic level can also be performed at the macroscopic level, that is, at a large scale. Its application will have far-reaching consequences, especially in computer and digital technology.
Quantum tunneling, in simple terms, is the process in which a particle, such as an electron, despite having low energy, crosses a barrier that requires more energy to cross. Such a barrier is called a potential barrier. This observation cannot be explained by classical physics or mechanics, so research has shown that the particle sometimes exhibits solid and sometimes wave properties. Also, the presence of a particle in a particular place is not certain, but rather probable. Although this observation is unacceptable to our intuition, it is the truth. From here the door opens to the wonder in the field of physics that has been surprising the human mind for the past century.
The discovery of quantum mechanics
An interesting story
In 1875, a physicist’s erroneous idea and his student Max Planck's Nobel Prize 1918:
One hundred and fifty years ago, a respected physicist thought that, "Physics is complete and there is nothing left to do in this field"!
Johann Philipp Gustav von Jolly
(September 1809 - December 24, 1884) was a German experimental physicist. He was a professor of physics at the University of Munich. One of Philipp von Jolly's students was Max Planck, whom Johann Philipp, in 1878, advised not to go into theoretical physics. Because he believed that there was nothing left in the subject of physics, everything that had to be discovered had already been discovered. Despite this advice, Planck continued to study physics and his later work led to the discovery of a modern branch of physics, quantum mechanics. He received the Nobel Prize in Physics in 1918.
Later in life Planck wrote: "When I began my university studies, I asked my esteemed teacher Philipp von Joly for advice on the state and prospects of my chosen field of study, physics. He described physics as a highly developed, almost completely mature science that would soon assume its final stable form through the important achievement of the discovery of the principle of conservation of energy. Theoretical physics was approaching its completion remarkably close to the same extent as geometry had centuries before.
The end of the idea of the completion of physics:
Philipp's idea could be considered correct to the extent of classical physics, at that time there was no concept of modern physics or quanta, in anyone's mind.
In the early twentieth century, Max Planck's genius and hard work led to the founding of modern physics. The discovery of quantum theory began a new and amazing era in modern physics. He received the Nobel Prize in Physics in 1918. The constant named after Planck, ħ.., is now used in most formulas of quantum mechanics. Planck's theory, also known as Planck's quantum theory, is the idea that energy is not continuous but instead is emitted or absorbed in the form of discrete packets called...Quanta... The energy of each quanta is directly proportional to the. Frequency of the radiation.., a relationship that can be expressed by the formula ....E=hν
Thus, the idea of physics being complete ended and a new field began to make progress, which discovered a new world and introduced the world to an amazing new technology. After Planck's discovery of quantum theory, scientists in this field made significant progress through experiments, which are still ongoing.
It is important to clarify that the ambiguity that arises from quantum tunneling, that it is a tunnel through which a particle reaches the other side of the barrier, is not at all the case. Rather, the particle behaves in the form of a probability wave, in which there is a small probability of finding the particle on the other side of the barrier, this probability is real and has been observed practically. It is as if the particle is present in two places at the same time. Quantum tunneling is a phenomenon in which particles cross a potential energy barrier whose height is greater than the total energy of the particles. This phenomenon is interesting and important because it violates the principles of classical mechanics.
A graph of the probability of a wave function crossing a barrier (quantum tunneling) shows that the probability density, , decreases exponentially inside the barrier and remains finite but small on the other side, allowing transmission even if the particle's energy is less than the barrier height. Key graphs often plot the probability density versus position, illustrating the wave function's smooth, non-zero nature within and after the barrier, unlike the abrupt drop to zero predicted by classical physics.
1933 Nobel Prize in Physics
Schrödinger Equation
At the beginning of the twentieth century, experimental evidence showed that atomic particles are also wave-like in nature. For example, electrons were found to give a pattern of diffraction of light when passing through a double slit, like waves of light. Therefore, it was reasonable to assume that the wave equation could explain the behavior of atomic particles. Schrödinger was the first to write such a wave equation in 1926, for which he was awarded the Nobel Prize in 1933.
solutions were found where the wave function penetrates into classically forbidden regions, i.e. where the total energy of the particle was lower than its potential energy in the region. Although the wave function is exponentially decaying under the barrier, for finite length barriers, the wave function exists also on the other side of the barrier. Thus, there exists a finite probability for the particle to pass the barrier, although it does not have enough energy to do so classically. An early successful application of this theory was the explanation of alpha decay, where the alpha particle is confined in the nucleus by a potential barrier but has a finite probability to tunnel through this barrier. Tunnelling also explained why radioactive decay is a probabilistic process, where the half-life crucially depends on height and thickness of the potential barrier. The possibility of a particle or wave function being on both sides of an obstacle at the same time is not just mathematical, but real. Although the mind is not intuitively ready to accept this fact, this phenomenon has reached the point of proof.
The 1973 Nobel Prize in Physics was awarded with one half to Leo Esaki and Ivar Giaever for their experimental discoveries regarding electron tunnelling phenomena in semiconductors and superconductors, respectively.
Giver’s 1960 experiments confirmed the existence of an energy gap in superconductors, something predicted by John Bardeen, Leon N. Cooper and Robert Schrieffer in 1957. Their BCS theory was awarded with the Nobel Prize in Physics 1972. The other half of the 1973 Nobel 2 (13) Prize in Physics was awarded to Brian Josephson, whose theoretical predictions are essential also for this year’s Prize
In 1984 and 1985, John Clark, Michel H. De Voret, and John M. Martinez conducted a series of experiments with an electronic circuit made of superconductors, conductors that can carry current without any electrical resistance. In the circuit, the superconducting conductors were separated by a thin layer of non-conducting material, a setup known as a Josephson junction. These scientists refined all the different properties of their circuit so much that they were able to control, explore, and measure the phenomena that occurred when current passed through the superconductor. The charged particles moving through the superconductor, together, formed a system that behaved as if it were a single wave function that filled the entire circuit. This macroscopic particle-like system is initially in a state in which current flows without any voltage. The system is trapped in this state, as if it were behind an obstacle that it cannot cross. In the experiment, the system demonstrates its quantum property by eliminating the zero-voltage state through tunneling. The appearance of voltage indicates that the system has changed.
Nobel Prize in Physics 2025
John Clarke, Michel H. Devoret, John M. Martinis
https://www.nobelprize.org/prizes/physics/2025/press-release/
The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics 2025 to the following scientists:
John Clarke, U of Cal., Berkeley, USA, Michelle H. Devoret, U of Yale, New Haven, CT, and U of Cal, Santa Barbara, USA, John M. Martinis, U of Cal., Santa Barbara, USA
A key question in physics is the maximum size of a system that can exhibit quantum mechanical effects
Their experiments on a chip showed that quantum tunneling, a process in quantum physics, is also practically possible at the macroscopic level, far beyond the particle or microscopic level.. This year's Nobel laureates conducted experiments with an electrical circuit in which they demonstrated both quantum mechanical tunneling and quantum energy levels in a system that is large enough to be held in the hand. Quantum mechanics allows a particle to move directly through a barrier, using a process called tunneling. As large numbers of particles are involved, quantum mechanical effects generally become extraordinary. The laureates' experiments proved that there is undeniable evidence of quantum mechanical properties even at the macroscopic scale. Readers interested in the scientific and mathematical details can read more by visiting this link: https://www.nobelprize.org/uploads/2025/10/advanced-physicsprize2025.pdf
Explanations of natural phenomena and applications to inventions:
1. The earliest successful application of quantum tunneling was the explanation of alpha particle decay. The alpha particle is limited by a potential barrier in the nucleus, but there is a limited chance that it will cross this barrier through quantum tunneling.
2. Sun, where the temperature and pressure are too low to allow two protons to overcome the Coulomb repulsion to form a helium nucleus, the tunneling principle allows fusion to occur.
3. Transistors are an example of quantum technology that is all around us.
4. Including quantum cryptography in computer microchips, quantum computers, and quantum sensors
5. Has a wide range of applications, such as scanning tunneling microscopes and tunnel diodes
This year's Nobel Prize in Physics has provided opportunities to develop the next generation of quantum technology.
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