빛의 역사: 파동에서 입자 이론으로의 진화

### 빛의 진화: 뉴턴의 입자에서 아인슈타인의 광자까지: 빛의 진화
* 🌞 고대부터 인간은 빛의 본질에 대해 호기심을 가져왔고, **17세기까지 학자들은 빛이 입자인지 파동인지에 대해 치열하게 논쟁**을 벌였습니다.
* 🔴 아이작 뉴턴은 프리즘을 이용한 실험을 통해 **빛이 입자로 구성되어 있다고 제안**했고, **180년 동안 그의 빛의 입자 이론은 과학계를 지배**했습니다.
* 🌊 토마스 영의 이중 슬릿 실험과 제임스 클러크 맥스웰의 빛이 전자기파라는 발견은 **뉴턴의 입자 이론에 도전**했고, **빛의 파동 이론이 지배적인 위치**를 차지하게 되었습니다.
* 💡 막스 플랑크의 흑체 복사에 대한 연구와 빛 에너지의 양자화는 **빛의 입자성에 대한 증거**를 제공했지만, 과학계는 이 이중성을 받아들이는 데 어려움을 겪었습니다.
* 🏅 알버트 아인슈타인의 광자 이론은 **빛이 입자처럼 행동하는 광전 효과**를 성공적으로 설명했으며, **콤프턴 실험**을 통해 빛이 입자로 구성되어 있다는 사실을 확실히 증명했습니다.
* 🔄 수 세기에 걸친 논쟁 끝에 과학자들은 **빛이 파동과 입자로 동시에 작용**한다는 사실을 인정하면서 빛의 파동-입자 이중성을 받아들이기 시작했습니다.
* 🔒 아인슈타인의 빛 입자 이론에 기반한 광전 효과는 **레이저 보안 기술, 자동 조명 시스템, 자동문, 스캐너, 내비게이션 시스템, 전자 계산기, 인공 위성 등**에 널리 사용되고 있습니다.

빛의 역사는 파동과 입자라는 이중적 성격을 드러내며 과학적 이해를 변화시켰습니다.

Every day, the rising and setting sun that illuminates the darkness that has been removed. Since ancient times, humans have been curious about the essence of this light. What is light? When you look at light from the perspective of particle-wave duality, how was it actually created? Until the 17th century, scholars fiercely debated whether light was a particle or a wave. However, at this time, a genius scientist emerged. The father of Optics, Isaac Newton. At that time, Isaac Newton, who was considered one of the greatest geniuses of humanity, used a prism to separate light into red, orange, yellow, green, blue, indigo, and violet, and conducted experiments to combine the various colors of light to create white light, proving that light is a composite entity. Furthermore, he assumed light to be composed of particles and explained the reflection, refraction, and dispersion of light by a prism. At that time, Isaac Newton was almost unreasonably pronounced as the only pronoun for scientists.

During the era when people believed in and respected Newton, his theory that light consists of particles was widely accepted. However, scientist Christian Huygens, who did not agree with Newton's particle theory of light, stated, If light is made up of particles, when light hits light, it should bounce off. It should scatter. However, no matter how much light you pile up against light, it does not spread in all directions. This means that light is fundamentally a wave. Not only Huygens but many other scientists continued to argue that light is a wave. Despite this, many did not believe them because Isaac Newton, a physics superstar, had great credibility, so scientists advocating the wave theory were refuted.

There was no opportunity, thanks to Newton's claim, people thought of light as particles for 180 years. Thus, the idea that light is particles dominated. Scientist Thomas Young conducts a double-slit experiment using light. The term slit means a narrow opening. Since there are two narrow openings, it's called a double-slit experiment. Placing a board with two holes and adding another board behind it, let's shine light towards the double slit for the first time. Thomas Young, who thought of light as particles, expected this. Hmm, some light will hit the wall and bounce off, while some will pass through the slits and reach the screen behind the wall. As we expected, the light passing through the holes on the board behind should stick together and create a pattern of lines on the screen.

I expected that, but the result was completely different. Naeun, what's going on? It's not 9 lines, but multiple lines coming out. How can scientists make multiple patterns appear? They start looking for past cases. However, if light is a wave, it is possible. If light is a wave, it can pass through two slits simultaneously from the beginning. If light is a wave, it matches the interference pattern of the double slit. In other words, the conclusion is that light is a wave. In the second experiment, Newton's light particles lost their power, and the wave theory of light became dominant again. In 1862, James Maxwell conducted an experiment to measure the speed of electromagnetic waves generated by electricity and magnetism. In this experiment, Maxwell deduced that the speed of electromagnetic waves is 300,000 km per second. No, it's exactly 300,000 km per second. The speed of electromagnetic waves coincides with the speed of light. Is this the moment where James Clerk Maxwell went crazy?

Maxwell, who was quick-witted, saw through that light in this experiment is a type of electromagnetic wave. So, gentlemen, electromagnetic waves are a dream, a house, or a ghost. Yes, that's right. It has been confirmed that light is indeed transmitted as electromagnetic waves, with the components of the electromagnetic field perpendicular to each other in the form of waves. With the introduction of Maxwell's wave equations, Newton's assertion of light as particles lost its strength, and the theory that light is a wave became much more dominant. On the other hand, Max Planck, who was studying blackbody radiation, realized the fact that the energy of light is intermittent in the process of explaining blackbody radiation. Let's think of it as a racing car. A car can run at speeds of 100km/h and 200km/h, but it is impossible to run at speeds between 200km/h and 250km/h. This fact that energy is intermittent is actually a characteristic of particles.

For example, let's consider the weight of a billiard ball to be 1kg. So, the weight of three billiard balls would be 3kg, as there are three balls. Unless we break the billiard balls, we cannot make 1.5kg or 2.5kg using only billiard balls. In other words, light energy can only exist as a multiple of a specific value. We call this quantization. Energy is not continuous but rather exists in discrete amounts. This sparseness of energy is actually a property of particles. The phenomenon occurring in blackbody radiation is something that cannot happen if light is considered as a wave, but on the contrary, if light is seen as particles, it is possible. Max Planck thought about this and said, For a light to be observed, the smallest unit must be one room leak. However, at that time, the theory that light is a wave was very dominant, and the idea that light is made of particles was unthinkable.

In the scientific community, due to the wave-particle duality of light, Max Planck, even after observing the fact that light behaves like particles, could not easily believe it. Instead, he cautiously expressed light as particles when announcing his groundbreaking research results. On the other hand, scientist Heinrich Hertz, who believed light to be a wave, accidentally discovered the photoelectric effect while conducting cathode ray experiments. The photoelectric effect refers to the phenomenon where electrons are emitted from a metal surface when exposed to light with a frequency higher than a specific threshold frequency. At that time, the scientific community strongly favored the wave theory of light, and they could not explain this photoelectric effect with the wave theory at all. However, at this point, the greatest genius scientist in human history appears to resolve all these debates.

At the time when Albert Einstein introduced the theory of light as particles called photons, which explained the photoelectric effect that wave theory could not, he perfectly explained the photoelectric effect. If you look closely, there are tiny particles, like grains, in light. This is what we call photons. The reason why electrons jump out when light above a certain frequency is shone on a metal is because photons of light collide with electrons. Photons act like particles when interacting with matter, and when they collide with electrons, they transfer their energy to the electrons, causing them to jump out of the metal. In this way, Einstein explained the photoelectric effect, which could not be explained by wave theory, with the theory of light particles. At that time, in the scientific community, claiming the existence of light particles was considered insane, but Einstein completely overturned the traditional theory of light as waves with the photoelectric effect.

He succeeds in winning the Nobel Prize in Physics by conducting an experiment that proves Einstein's particle theory of light. He precisely shoots a beam of X-rays at a blackboard and discovers that light moves like a billiard ball. Now, let's roll the yellow ball towards the red ball. Depending on the angle of impact, the yellow ball will bounce off just as much as the red ball spins. Here, the yellow ball represents a photon, and the red ball represents a black carbon particle. If light were not particles, this phenomenon could never occur. At that time, with the Compton experiment, it was clearly demonstrated that light is composed of particles, and with this experiment alone, he wins the Nobel Prize in Physics in 1927.

So, for hundreds of years, the scientific community has been fiercely debating whether light is a particle or a wave. In the time of Newton, the particle theory of light prevailed. Then, during the era of Thomas Young and Maxwell, the wave theory of light dominated. Once again, with Einstein's discovery of the photoelectric effect, the particle theory of light became superior. After centuries of arguing whether light is a wave or a particle, scientists were at a loss. In the scientific community, the concepts of particles and waves were considered mutually exclusive. However, in experiments where neither theory seemed to fit, sometimes the wave theory had to be correct, and in other experiments, the particle theory had to be true, yielding strange experimental results. At this point, scientists began to accept the duality of light, acknowledging that sometimes it behaves as a wave and other times as a particle.

Where exactly will Einstein's photoelectric effect be used? Let's end it with a movie reference. In the movie Ocean's Twelve, the world's greatest thief, François Toulour, infiltrates a secure room to steal a valuable treasure. This security room is equipped with a special laser that, if touched by a body, triggers the alarm, leading to the failure of the heist. From the thieves' perspective, this laser security device is quite annoying. However, what is the principle of this security laser? The principle of this security laser is precisely the photoelectric effect. According to the photoelectric effect, light energy can be converted into electrical energy and vice versa. Let's take a look at the laser beam. When a current is applied to a semiconductor, - cut off

When electrons move, light energy is emitted. In laser security technology, analyzing the point where the laser touches the body and reflects back with infrared light can distinguish between humans and objects, calculate the time it takes for the light to reflect back, and determine the position and size accurately. Calculations through light are extremely precise. Even in severe conditions like heavy fog or rain, objects can be detected and whether it is a living organism that is moving can also be detected. This laser sensing technology that uses light is thanks to Einstein's photoelectric effect. The reason we can see such great scenes in movies is also due to the photoelectric effect. Furthermore, areas where the photoelectric effect is used include automatically turning on and off lights, automatic doors, scanners, navigation systems, electronic calculators, artificial satellites, etc. Oh, today's lighting article was published. We really covered a lot of English today, right? However, the properties of waves and particles simultaneously.

Is having this all indeed material? Could it possibly be both a wave and a particle at the same time? Would it make sense to say that matter has eyelashes? The content of tonight is the history of quantum mechanics. So far, it has been about movies and YouTuber reviews.

정말 이것만 증명하면... 무조건 노벨상 탄다고? 빛은 입자일까 파동일까?

과학과 영화가 중첩되어 있는 유튜버 리뷰엉이.
비즈니스 문의 - vvongyea@gmail.com

리뷰엉이: Owl's Review

아이작 뉴턴의 프리즘 실험은 빛이 복합적인 실체라는 것을 증명했고, 빛의 입자 이론이 널리 받아들여지게 되었습니다.

반대에도 불구하고 뉴턴의 이론은 그 신뢰성 덕분에 180년 동안 지배적이었습니다.

토마스 영의 이중 슬릿 실험은 빛의 파동 이론에 대한 증거를 제시하며 뉴턴의 입자 이론에 도전장을 내밀었습니다.

과학자들은 처음에 과거의 사례를 통해 빛의 패턴을 설명하려고 노력했고, 결국 빛은 파동으로 작용한다는 결론에 도달했습니다.

제임스 맥스웰의 실험은 뉴턴의 입자 이론을 대체하는 전자기파로서의 빛을 확인했습니다.

그러나 막스 플랑크의 흑체 복사에 대한 연구는 이에 도전하여 빛의 에너지 양자화와 파동-입자 특성의 이중성을 인정하게 되었습니다.

빛의 이론의 진화: 파동에서 입자까지

막스 플랑크는 빛이 파동과 같은 거동을 한다고 믿었지만 입자로 조심스럽게 설명했고, 하인리히 헤르츠는 우연히 광전 효과를 발견했습니다.

알버트 아인슈타인의 광자 이론은 광전 효과를 성공적으로 설명하여 기존의 빛의 파동 이론에 도전장을 내밀었고 노벨 물리학상을 수상했습니다.

1927년 콤프턴 실험은 입자로서의 빛에 대한 이해를 더욱 공고히 하여 빛의 구성을 증명한 공로로 또 다른 노벨상을 수상했습니다.

수세기 동안 과학계는 빛이 입자인지 파동인지에 대해 논쟁을 벌였고, 입자 우위론과 파동 우위론이 시간이 지남에 따라 바뀌었습니다.

결국 과학자들은 빛이 파동과 입자 모두로 작용할 수 있다는 사실을 인정하며 빛의 이중성을 받아들였습니다.

아인슈타인이 발견한 광전 효과의 원리는 빛 에너지를 전기 에너지로 변환하여 침입자를 감지하는 영화 '오션스 트웰브'의 보안 레이저에 사용되었습니다.

레이저 보안 기술에 대한 광전 효과의 영향

전자가 움직이면 빛 에너지가 생성되는데, 이 빛 에너지는 레이저 보안 기술에 활용되어 사람과 물체를 구분하고 위치와 크기를 정확하게 파악하는 데 사용됩니다.

광전 효과를 기반으로 하는 이 기술은 악천후 속에서도 움직이는 물체를 정밀하게 계산하고 감지할 수 있습니다.

광전 효과는 조명 시스템, 자동문, 스캐너, 내비게이션 시스템 등 다양한 응용 분야에서도 널리 사용되고 있으며 양자역학의 역사에서 기본이 되는 개념입니다.