#158 لغز الطاقة: من البندول إلى النجوم... القوانين واحدة مع د. سعد عيسى

What is energy? Is it merely a physical concept, or is it the key to understanding the entire universe? In this episode, Dr. Saad Issa, Professor of Physics at Al-Azhar University, returns for a discussion that takes us on a journey to understand one of the most mysterious and controversial concepts in science: energy. Dr. Saad emphasizes that there is much misunderstanding surrounding the meaning of "energy," and that understanding it is crucial because it is one of the concepts that most helps us understand how the world works. Paradoxically, physicists, despite their ability to measure it and predict its behavior with astonishing accuracy, do not have a definitive definition of what it is. If you were to ask the world's leading physicists: "What is energy?" they might explain what it does and how it is measured, but they wouldn't be able to tell you what it is at its core. Dr. Saad discusses the idea that the universe consists of energy, matter, space (which makes up most of it), and information. He also explains that what we know about matter and energy represents only about 4% of the universe, while the rest comprises dark matter and dark energy. The term "dark" here means that we do not yet know their true nature. We also trace the historical journey of understanding energy; from Newton's laws to the Industrial Revolution and the invention of the steam engine, whose workings took scientists decades to understand, leading to the emergence of thermodynamics and the formulation of its laws. We learn how the first law of thermodynamics, which states that energy cannot be created or destroyed, but rather transformed from one form to another, was developed. The episode also addresses: Why is energy one of the greatest mysteries of physics? Is energy a fundamental entity in the universe or merely a property describing physical systems? Can energy be sensed, or is it only known through measurement? Why do the laws of physics remain constant everywhere and at all times? How did Emmy Noether's symmetry theorem lead to a deeper understanding of the law of conservation of energy? How does the example of throwing an object into the air illustrate the relationship between gravity, kinetic energy, and potential energy? What is kinetic energy, and how does it transform between different forms of energy? What does the equation E = mc² mean, and how did it change our understanding of the relationship between matter and energy? Does the concept of "nothingness" in physics differ from its concept in philosophy, or are there points of convergence between them worthy of consideration? What is time? And how does physics view it? What is entropy, and why is it related to the so-called "arrow of time"? How does it explain the tendency of natural processes toward increasing randomness, and what is its relationship to energy and thermodynamics? This episode combines the history of science, physics, and philosophy, opening the door to major questions about the nature of reality and the universe we live in. To follow Dr. Saad:   / 1bimuwirsf   If you enjoyed the episode, don't forget to support the channel by liking and subscribing, and share your thoughts in the comments: In your opinion, which idea in this episode changed your view of energy or the universe the most? ⚡ Join this channel to get access to perks:    / @fromcairopodcast