If there is no "light quantum theory", will the door of quantum mechanics open?

Einstein is the most familiar great scientist, and his popularity is only increasing, because the predictions left by Einstein have been verified with the development of science and the progress of observation methods in recent years. April 10 The publication of the first human black hole photo once again proves that Einstein is correct. Many friends are most familiar with Einstein's achievements in space-time and gravity, but Einstein's achievements in quantum mechanics are also enormous. His? Optical quantum theory? It not only explains the photoelectric effect, but also lays the foundation for quantum mechanics. Light quantum also directly leads scientists to discuss the nature of light? The wave-particle duality of light subverted the whole scientific community in the 20th century.

Hertz discovers photoelectric effect

1887, in a series of experiments showing the existence of electromagnetic waves, German physicist Heinrich? The photoelectric effect was first observed by heinrich hertz. He inadvertently noticed that between two metal balls, if one of them was irradiated by ultraviolet light, the spark between the two metal balls would light up. What does he think of this? A brand-new and very puzzling phenomenon? After months of research, I can't come up with any explanation, but I think, of course, it's wrong. This phenomenon is limited to the use of ultraviolet rays. Unfortunately, Hertz died young at the age of 36 in 1894 without waiting for this phenomenon to be explained.

Later, Hertz's former assistant Philip? In 1902, Philipp Lenard further unveiled the mystery of photoelectric effect. When he put two pieces of metal into a glass tube and exhausted the air, he found that this phenomenon would also happen in a vacuum. Leonard found that when the wires on each metal sheet are connected to the battery, if the metal sheet is irradiated by ultraviolet light, it will generate current. This photoelectric effect can be explained by the release of electrons from the irradiated metal surface. When ultraviolet light shines on the metal plate, some electrons get enough energy to escape from the metal plate and reach another metal plate through the space, thus completing the primary energy generation. Photocurrent circuit However, Leonard also found some phenomena that contradict the existing physics. It's Einstein's turn and his light quantum.

Einstein and his light quantum

The intensity of light determines the number of electrons that are kicked out. It is expected that when the beam intensity is increased to make it brighter, the number of electrons released from the metal surface will remain unchanged and the energy of each electron will be enhanced. But Leonard found the opposite: more electrons were released, but the energy carried by each electron did not increase. Einstein's answer to quantum theory is concise and neat: if light is composed of quanta, then strengthening the intensity of the beam means that there are more quanta in the beam. When a stronger beam hits the metal plate, the increase in the number of light quantum leads to a corresponding increase in the number of electrons released.

The energy of released electrons is related to the frequency of light. Leonard's second strange discovery is that the electrons released are not limited by the beam intensity, but by the beam frequency. Einstein has a ready-made answer to this. Because the quantum energy of light is proportional to the frequency of light, the quantum energy of red light (low frequency) is lower than that of blue light (high frequency). Changing the color (frequency) of light will not change the quantum number in the same intensity beam. So no matter what color the light beam is, the same number of quanta hitting the metal plate will release the same number of electrons. However, because light with different frequencies is composed of quanta with different energies, the energy of released electrons will be larger or smaller, depending on the light used. When ultraviolet light is used, the maximum kinetic energy of electrons is greater than the kinetic energy released by red quantum.

Work function of electron? There is another puzzling phenomenon in the work equation. Any particular metal has the lowest or? Critical frequency? Below this frequency, no matter how long or how strong the metal is irradiated, it will not release electrons. However, once this critical point is crossed, electrons will be released, no matter how weak the beam is. Because Einstein introduced a new name? Work function? That is, the concept of work function, so his light quantum theory gives the answer again.

Einstein regarded the photoelectric effect as a result, that is, electrons need to get enough energy from light quantum to overcome the force of leaving it on the metal surface before they can escape. The photoelectric effect is such a result. Einstein called it. Work function? , is the minimum energy required for electrons to escape from the metal surface, which varies from metal to metal. If the frequency of light is too low, there is not enough energy for electrons to break through the binding force that fixes them in metal.

Einstein compiled all this into a simple equation: the maximum kinetic energy of electrons released from the metal surface is equal to the energy of light quantum absorbed by it MINUS the work function. Using this equation, Einstein predicted that if the corresponding relationship between the maximum kinetic energy of electrons and the frequency of light used is drawn as a graph, then this graph will be a straight line, starting from the critical frequency of metals. The inclination of this line, no matter what metal is used, will always be exactly equal to Planck constant H. This is Einstein's explanation of photoelectric effect, but the theory needs experimental verification, so some experimental physicists specialize in verifying the amazing theory of theoretical physicists.

The photoelectric effect equation is verified.

American experimental physicist Robert? Millikan spent 10 years to test Einstein's 1905 photoelectric effect equation. Facts have proved that Ince is right, absolutely right. About Einstein? Is he right? I have heard this sentence many times now. The release of black hole photos on April 10 once again proves that Einstein is right. The great man went further and further on the right path.

In short, it can be said that there are a lot of problems in modern physics. There is hardly an Einstein who has not played a significant role in some important issues. 192 1 year, Einstein was awarded the late Nobel Prize in Physics, which clearly pointed out that the formula given to him described the law of photoelectric effect, rather than his explanation based on the quantum theory of light. After all, his optical quantum theory is too subversive for physicists to accept. However, this has directly triggered the debate among scientists on the nature of light, and the door of quantum mechanics will gradually open.