Воскресенье, 14.04.2024, 04:49
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I. Watch the vieo below and find in it English equivalents for the following Russain words:

  1. выстрелиаемый так, чтобы пролететь через две узкие щели
  2. дуализм частиц и волн = 
  3. интерференционная картина = 
  4. эволюция волновой функции =a 
  5. распределение вероятностей = a 
  6. квантование энергии =o  
  7. создавать интерференционную картину =to
  8. предсказывать, где частицы, скорее всего, появятся =towhere the
  9. получать распределение вероятностей =to
  10. колебаться определенными специфическими способами=to

If you guessed less than half of the words correctly, reload the page and it it again

II. Prepare answers to the quesitons:

  1.  What is the purpose of the map of quantum physics mentioned in the video? (Timestamp: 0:07)

  2. What were some of the mysteries that led to the development of quantum mechanics? (Timestamp: 1:26-1:32)

  3. What experiment demonstrates the interference pattern and provides evidence for particle-wave duality? (Timestamp: 2:40-3:05)

  4. How are particles described in quantum mechanics?  (Timestamp: 3:05-3:10)

  5. What is the Born rule?  (Timestamp: 3:17)

  6. What is the Heisenberg uncertainty principle?  (Timestamp: 3:38)

  7. What does Bell's theorem demonstrate?  (Timestamp: 4:28)

  8. Why do quantum objects have energy quantization? (Timestamp: 4:46-5:00)

  9. What is the significance of the zero-point energy? (Timestamp: 5:31-5:56)

  10. What is the main goal of the video regarding the concepts of quantum physics? (Timestamp: 5:56)

III. Watch the video up to the 7th min again and fill in the gaps with the words from task I.

I’ve been fascinated with quantum physics for a very long time, so much so that I did a PhD in it.  I wanted to share the subject with you, so I made this map of quantum physics to lay out the ideas within the subject, to set some bounds on it, so you know it's not endless, and to introduce you to lots of concepts that, if you are interested in them, you can dig deeper. When you are approaching a subject like this that's so complicated, it can be quite challenging because you don't know where to start and you don't know how all the concepts relate to each other, so hopefully, this will put everything in context. Okay, first, let's just look at the geography of this map. To the northwest, we have the foundations of quantum physics, and then traveling further south, we go through quantum to quantum technology. And in the south and east, we have the academic disciplines of quantum physics. In the center, quantum theory, and in the north and east, the theoretical future of quantum physics, beyond what we already know. That is your quantum forecast for this video. I've also made a poster of this available, so if that's of interest, check it out in the description below. And without further ado, let's get into it.  The theory of quantum mechanics developed from a set of mysteries in the late 1800s and early 1900s, where reality didn't quite the models of physics at the time.  We now call these older theories of physics classical physics. There were several clues that pointed to some deeper model of reality. When light shines through a gas, the gas absorbs and emits specific frequencies of light, which we call atomic spectra. This was a mystery. There was no known classical explanation for this. And there was a lot of confusion about how atoms could be stable. In classical physics, the electrons should continually radiate their energy and collapse into the nucleus. The source of radioactivity was unknown. When you look at a hot body like the Sun, it electromagnetic radiation in many different , and this distribution of light is called blackbody radiation. Now, the distribution we observe from black bodies didn't match the predictions of classical physics. And when you shine light on certain metals, you can make electrons fly off. This is called the photoelectric effect. This experiment showed that light didn't behave like a wave but like a of particles and was the first indication of particle-wave duality. All of these mysteries can only be explained with the laws of quantum mechanics. Let's take a look at the foundations of quantum mechanics.A fact, in the mathematics of quantum mechanics, all particles are described as waves by a thing called a wavefunction, and the way this wave evolves over time is described by the famous Schrödinger . But we can never see these quantum waves as all we ever detect are particles, but from the wave function, we can predict where the particles are likely to turn up.  But we have to do a bit of math on them first called the Born rule, which derives a probability distribution of where the particle might be from the wavefunction.  So quantum mechanics tells us that the universe is fundamentally probabilistic. We don't know exactly where the particle will turn up; the best we have is a probability of where it will be. This brings us to the Heisenberg uncertainty principle, which says that quantum objects don't have definite values for certain pairs of properties, for example, position and momentum.You can get a of this from these pictures. The first is a snapshot where the particle had a definite position, but we have no information about its momentum, as in the direction it was going and how fast it was traveling.  The second picture has a motion which tells us about its , but now we have an uncertainty about where the particle was when we took the picture.  Another important equation is the Dirac equation, which extends the Schrödinger equation to include special relativity and describe particles with high kinetic energy.  And another important foundational concept is Bell's theorem, which proved that the uncertainty in quantum mechanics is not caused by our of knowledge about hidden variables but is a fundamental part of the universe. It also led to the concept of non-locality, which we'll meet a little later Finally, we get to energy quantization, which is where objects like electrons can only have certain definite energies when they are in atoms. This is where the quantum in quantum mechanics comes from.  And this quantization is because their wave functions can only vibrate in certain specific ways. You can see this if I reduce the atom to one dimension. The energy field of the proton in the atom is represented by this shape. You can think of the electron as being attracted to the proton and so it wants to fall into the bottom of the bucket.  But because the electron is a wave, it can only exist in certain modes shown here, which are just like the vibrational modes of a guitar string, with higher frequency modes having a higher energy.  This also means that quantum objects always have a minimum amount of energy known as the zero-point energy, and this applies not only to electrons in atoms but to everything, even to empty space itself.  Now I understand that this is all quite a lot to take in if you are new to this. But don't worry if all these terms are confusing. The point of this video is to expose you to a lot of the concepts in quantum physics just so that you know they exist.

 

Send a screenshot of your answer results to your teacher,

IV. Prepare good reading of the text above. Repeat after the lecturer in the video.

V. Prepare a summary of the video.