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Thank you so much, George! I'm glad you enjoyed the video-it means a lot! Are you studying physics, or do you just have an interest in quantum mechanics? I'd love to hear more about what you find fascinating in the subject! 😊

Hi Tommaso, thank you for your kind words! I'm so glad you're enjoying the playlist. I studied a lot of quantum mechanics in graduate school and wanted to turn my notes into a set of lectures to help make the subject more approachable for others. Quantum mechanics is definitely challenging, but I believe it could be easier to learn if it were taught differently. While I don't have the perfect solution, I do feel the current state of teaching quantum mechanics has room for improvement. I'd love to hear your thoughts-are you studying physics or just exploring the subject?

Thank you for the kind words! Lee Guthrie’s experiment on the mechanical quantum spring is a cornerstone of scientific achievement (or at least its really cool). I’m glad you found the explanation helpful. Let me know if there’s anything specific you’d like to dive deeper into!

You might be right but I don't completely understand your explanation?

Many examples quantum physics DO use 2D or simplistic representations to gain a grasp of the physical situation. Many historical equations have been resolved by dismissing variables that have a limited influence on the system. Schrodinger, Heisenberg, Einstein and others ALL used similar techniques to solve "unsolvable" problems. This technique may prove useful in studying failure modes in construction, where an applied force doesn't result in a gradual deformation, but sudden failure.

Thank you for your question! Let me clarify why the intensity at 45 degrees isn’t zero. Initially, the light is vertically polarized, meaning its electric field vibrates only in the vertical direction. When this light passes through a polarizer set at 45 degrees to the vertical, the polarizer allows only the portion of the light’s electric field aligned with its axis (at 45 degrees) to pass through. The remaining portion is blocked. Since the polarizer is not completely misaligned with the original vertical direction but instead at a 45-degree angle, it allows part of the light to pass through. The intensity is reduced because only a fraction of the light’s energy is aligned with the polarizer’s axis, but it’s not zero. The light coming out of the polarizer is now polarized at 45 degrees. If the polarizer were set completely perpendicular to the light's original polarization (like at 90 degrees), then the intensity would indeed be zero. However, at 45 degrees, some light always gets through because the electric field has a component in that direction. I hope this clears up your confusion! Feel free to reach out if you have more questions.

The formula for electromotive force (EMF) is indeed EMF=−L di/dt The negative sign reflects Lenz's law, which indicates that the induced EMF opposes the change in current. However, when discussing the magnitude of the EMF, the absolute value should be taken, which is why I omitted the negative sign in earlier discussions. To clarify, absolute value symbols (∣EMF∣) should have been placed around the EMF symbol to indicate this explicitly. At 5:11 in the video, the question presents a positive EMF and asks how the current is changing. A positive EMF implies that the current must either be: Slowing down in the rightward direction, or Speeding up in the leftward direction. In either of these scenarios, the current is changing in a way that requires a positive rightward EMF to attempt to maintain its flux. This aligns with the principle that the inductor generates an EMF to oppose the change in flux, as dictated by Lenz's law.

Hello Thomas, thank you for commenting. Can you please be more specific. What do you mean by the equivlents?

Thanks for your comment it was fantastic!

What does this comment mean?

Hi Lee, thank you for your kind comment! I’m thrilled to be working with you on your quantum springs project. I’m looking forward to sharing the short video this December!

@ I am looking forward to seeing your video too. Talk to you soon, have a great holiday!

Thank you I appreciate the positive feedback.

Clearly with vehicle to grid use becoming perhaps common maybe that is where much of the multi day battery storage future lies!?🔋🗽

Thanks for your insightful comment! You're absolutely right that hydropower has remained stable, and as we adopt more solar and wind energy, multi-day batteries play a crucial role in storing excess energy generated during peak times. This is central to Tony Seba’s vision, as he predicts that a combination of solar, wind, and batteries (SWB) will revolutionize energy systems, enabling clean energy to be produced abundantly and at near-zero marginal cost. In fact, he believes that by 2030, such systems could replace much of our reliance on fossil fuels, creating what he calls "super power"-enough energy to power new industries and dramatically lower electricity costs globally. Regarding batteries' environmental impacts, there are indeed significant concerns. The extraction of lithium and other metals used in battery production can cause environmental degradation, particularly through mining activities. Improper recycling or disposal of batteries can also lead to harmful chemicals like lead or cadmium leaching into the environment, potentially affecting both ecosystems and human health. However, innovations in battery recycling, like those from companies such as Redwood Materials, are improving the environmental footprint of these technologies, ensuring that materials can be reused and reducing the reliance on new mining operations. So while there are challenges, advances in storage technology, such as better recycling processes and safer disposal methods, are helping to mitigate the environmental impact, supporting Seba's dream of a clean, renewable energy future​. I hope it happens but I don't see it happening quickly enough yet.

@chrisconklin2981 Thank you for your comment! I appreciate your feedback and the opportunity to clarify my approach. My presentation was based on an article I read in Scientific American, where I reported the information as presented in the article. Additionally, I looked up some data from the U.S. Energy Information Administration to cross-reference and provide more context. I never claimed to be an expert in this field, and my goal was to explore whether the article gave accurate information, not to present myself as an authority on renewable energy. As a physicist with a PhD, I am comfortable analyzing scientific articles and interpreting their implications based on my background in physics. Although my direct research experience isn't in alternative energy, I do understand the underlying physics of photovoltaics and energy extraction from the sun, particularly from a materials science perspective. However, my intention with this video was more to ask questions and initiate discussion rather than to present definitive conclusions. I would genuinely welcome more informed perspectives, and I encourage anyone with greater expertise on the state of solar energy or global warming to share what they know with me and others in the comments. Could you clarify which specific statements you believe were inaccurate or missing key facts? I'd love to hear your take and improve the discussion going forward.

Thanks for your comment. It appears to be misleading.

@@acephysics123 I'm basically agreeing with your video. The article might be cherry picking a day when everything aligns but that could be far away from the average energy produced by WWS. It's a step in the right direction, but still a long way from phasing out fossil fuels, which I'd love to see. My thoughts are we would get better results through smarter use of energy rather than expecting renewables to have a big impact in the short term.

Exactly, it's frustrating how the government hasn't provided clear and straightforward information on this. Explaining the trade-offs between different energy storage and production methods should be transparent and accessible to everyone. It feels like the complexity is being exaggerated or maybe even obscured on purpose, which leaves me questioning their motives. Clear answers would help people make informed decisions about energy policy.

can you make more petroleum and put it back in the ground? No. Pumping oil is not emptying storage, it's mining.

@AlanPeery, thanks for your thoughtful comment! You’re right that we can’t make more petroleum and put it back in the ground, and mining it isn’t the same as accessing a renewable resource. Petroleum can be stored at relatively low cost, but once it’s burned, it releases carbon dioxide and contributes to environmental damage. On the other hand, batteries don’t produce emissions during use, though they do come with environmental costs in manufacturing and disposal, and their energy density is lower. Still, they offer a cleaner alternative, especially when paired with renewable energy. I agree with the point John made about how electricity storage costs, especially with batteries, are much higher, but I believe as technology improves, we can bridge the gap. Appreciate the discussion!

Dear @jeremyvirin6532, Thank you very much for your thoughtful comment! This is exactly the kind of discussion I was hoping for when I made the video. It’s great to see young people who are optimistic and genuinely care about the environment. I really appreciate your analysis, especially regarding global GHG (greenhouse gas) emissions and the important role of China, India, and other developing countries in the conversation. While it is disheartening to see GHG emissions still rising, I remain hopeful that we'll see breakthroughs in energy innovation. It’s arguably one of the most critical problems in science today. Your insights on the battery's impact and the future of renewable energy are particularly interesting, and it will be fascinating to see how technology and policy shape the transition over the coming years. I also believe there are significant opportunities in alternative and green energy. If you're interested in this field, you could really make a difference and build a rewarding career. There’s no doubt that this sector will be growing in the years to come! Thanks again for sharing your thoughts - I look forward to more discussions like this! Best, Jacob

Dear @jeremyvirin6532, Thank you very much for your thoughtful comment! This is exactly the kind of discussion I was hoping for when I made the video. It’s great to see young people who are optimistic and genuinely care about the environment. I really appreciate your analysis, especially regarding global GHG (greenhouse gas) emissions and the important role of China, India, and other developing countries in the conversation. While it is disheartening to see GHG emissions still rising, I remain hopeful that we'll see breakthroughs in energy innovation. It’s arguably one of the most critical problems in science today. Your insights on the battery's impact and the future of renewable energy are particularly interesting, and it will be fascinating to see how technology and policy shape the transition over the coming years. I also believe there are significant opportunities in alternative and green energy. If you're interested in this field, you could really make a difference and build a rewarding career. There’s no doubt that this sector will be growing in the years to come! Thanks again for sharing your thoughts - I look forward to more discussions like this! Best, Jacob

A vary concise reply thanks

I’m new to making videos, but I’ve studied quantum mechanics extensively in both undergrad and grad school. It's a tough subject, and often, it's not taught well. With just a few clear examples, though, it could be so much easier. I struggled with it too, and I believe breaking down problems simply can really help others avoid the same challenges. I’m not claiming to be the best teacher of quantum mechanics, but the way quantum mechanics is currently taught isn't good enough-it needs a change to make it clearer for students.

By the way are you real? Your screen name seems questionable?

@@acephysics123 I am not robot, if that’s what you are asking. I commented because I thought your video is very clear. I always try to skip the problem solving part in QM books cuz the problems are all repetitive and don’t provide a lot of insight. But the examples in your video are straight to the point.

@@acephysics123 If I may also ask, any resource recommendations for self studying QM?

@profxjkun9482, I’m glad you’re not a robot! I studied physics as an undergraduate at Columbia University, where I took four semesters of quantum mechanics. Later, I earned my PhD in physics at Florida State University, taking an additional eight semesters in quantum-related courses, including graduate quantum mechanics, quantum field theory, and condensed matter physics. In my experience, quantum mechanics is often not taught well. Most textbooks tend to explain the material in the same way, often with methods that aren't very effective. I believe that some modern physics books, like Concepts of Modern Physics by Arthur Beiser, Modern Physics by Paul A. Tipler and Ralph Llewellyn, and Quantum Physics by Eisberg and Resnick, are good starting points. I also recommend working through problems with a solutions book, such as Problems and Solutions in Quantum Mechanics, to check your progress along the way. The Feynman Lecture Volume 3 is ok, I haven't found any TH-cam channels that are particularly great for quantum mechanics. I think the way the subject is currently taught makes it inaccessible for most people, and unfortunately, all the textbooks seem to take the same approach, just with different authors. There’s definitely room for improvement in how quantum mechanics is explained. In my experience the modern physics books are the best.

@shoobidyboop8634 I totally get that! Sometimes the math can be overwhelming. I once got a similar comment, and I offered to explain the basic concept of quantum mechanics in 15 minutes over Zoom, with the condition that I'd record it. If it went well, I'd post it on my TH-cam channel; if not, I wouldn’t. They never replied, but I’m extending the same offer to you. I can break down the basics of the math and concepts from this video in a short session. If you're interested, let me know! Best, Jacob

@@acephysics123 Thanks, I'll give that some thought, you seem incredibly mathematically well-versed.

@@shoobidyboop8634 Ok, the offer stands for a week. Nothing is as hard as it looks.

What is the answer to your pop quiz?

@@acephysics123 Heh, the layman would say, of course, John von Neumann. And you?

Dear @shoobidyboop8634, thank you so much for leaving a comment and for the positive feedback! I’m glad you enjoyed the overview. Where are you from, and how are you doing? Do you use solar energy or any other form of renewable energy yourself? I'd love to hear your thoughts! What does your screen name mean?

@@acephysics123 AZ, great, no just interested in this and that, scrn name meaningless. You my friend have what's known among us plebes as an estimable intellect, congrats!

@@shoobidyboop8634 @shoobidyboop8634 Thanks! Appreciate the compliment. By the way, what's your take on alternative energy sources like solar or wind? Do you think they can fully replace fossil fuels in the near future?

Dear @verttisahala8457, Thank you so much for your comment and for watching my video! I understand that quantum mechanics can be tricky, but I appreciate your curiosity. I have an offer for you, though I completely understand if you don't take me up on it: If you'd like, I can send you a Zoom link and explain the fundamentals of quantum mechanics in a 15-minute session. There's just one condition-I'd like to record our meeting, and if it goes well and you feel you've gained a better understanding of the material, I’d love to post it on my page. If it doesn’t go as planned, no worries-I won’t post it. My goal is not to embarrass you, but to help clarify these concepts and reply meaningfully to your comment. Let me know if you're interested! Best regards, Jacob

@TheMemesofDestruction, YOU. ARE. A. LEGEND. Your comment has not just made my day-it has made my year, my decade, and probably the next millennium. I’m actually considering renaming my entire TH-cam channel in your honor. In 5 months of making these videos, I've gotten around 10 comments, so naturally, I’ve already started planning a parade in your name. I’m going to print this comment on a 50-foot banner, hang it outside my house, and possibly get it tattooed on my forehead. I’m calling the local news station as we speak, so the whole world can know about this historic moment. Honestly, your comment has given me the motivation to produce enough videos to last until the year 3000. I might even write a song about it and turn it into a national anthem. Thank you for single-handedly altering the course of human history with this one comment. I’m off to build a statue in your honor. All the best, and may every single one of your endeavors be showered with victories. By the way please like the video if you have not done that yet.

Yep lol, thanks for the comment!

Thank you for the support I really appreciate it!

Hi Enya! Thanks for your great comment! It was awesome having you in the video, and you did a fantastic job answering the question. You're clearly a great math and science student. Please like the videos and subscribe to my channel for more physics and math content. Keep up the great work!

hi enya orz

Maxwell's demon seems to challenge the second law of thermodynamics by selectively sorting particles to lower entropy. However, the key lies in the information processing involved. To make decisions, the demon must gain and store information about the particles' states, which requires energy. When the demon erases this information, it expels energy, leading to an increase in the system's entropy. This means that while the demon might temporarily reduce entropy locally by sorting particles, the overall entropy of the system still increases due to the energy costs associated with information processing. This upholds the second law of thermodynamics, as the total entropy of the universe continues to rise.

Thanks for watching the video and leaving a reply! An isolated system is one where no heat or mass can enter or leave. If we consider the two boxes and the demon as one system, energy can transfer within the system-between the demon and the boxes-but no energy can leave the system. Think of it like your house being an isolated system: heat could move from one room to another, or from you to the house, but none could escape (but in reality a lot of heat can escape your house, pretend it can not.) Are you a physics student, and have you heard of Maxwell's demon before?

I didn’t make it to the NBA-shocking, I know. But there's still hope! All I need is for everyone else on Earth to suddenly lose the ability to use their legs. I mean, what are the odds, right?

@@acephysics123 😂😂😅 hahaha

Dear @massimilianodellaguzzo8571, First of all, were there really 8,570 other people with that same name? Let me make sure I understand: you're imagining a scenario where a train drives into a swimming pool. If the pool shrinks, the train might drive over it; if the train shrinks, it might sink into the water. I think that even if the pool is smaller than the train, it would still go into the water because trains aren't designed to drive over water. Regardless, that's a creative way to set up the problem! Thank you for your comment, and I hope you're doing well. By the way, where are you from?

@@acephysics123 " First of all, were there really 8,570 other people with that same name? " : the other 8570 people are in space, I'm on Earth and we are verifying the twin paradox (8571 twins, a beautiful experiment) " I think that even if the pool is smaller than the train, it would still go into the water because trains aren't designed to drive over water. ": your answer doesn't satisfy me but I think it's a right answer 😉 I'm Italian and I hope you're fine too...😊

@@massimilianodellaguzzo8571 Grazie per la risposta fantastica!

Hi, thank you for your nice comment! At some point I might make an update with entropy and chemical potential. The next video in this series will be on polarization, digital polarimeters and LCD. I think it will be a great video. You should watch that one as well. I have a feeling based on your comment that you might check that video out.

That is a really cute dog!