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Current time:0:00Total duration:9:30

Video transcript

I could imagine that even the earliest human beings are possibly free human beings had asked themselves the questions why am I here what is the nature of reality why is the universe organized the way that it is and these questions are what we attempt to answer in the field of physics in the field of physics which you could view maybe right after mathematics as the purest of of the sciences so you have math which is very pure and then on that foundation of math you have physics and physics really does try to use that mathematics along with some core ideas to explain the phenomena all the phenomena of the universe and physicists will be the first to admit that they are just beginning to understand the nature of reality the nature of everything around us now a lot of times we think physics is only limited to things like cosmological phenomena or getting rockets into space or how waves move or building structures but physics is the foundation for all of the other sciences when we think about chemistry when we think about chemistry which is at the end of the day interactions between atoms those interactions are really physics based interactions so chemistry chemistry is actually laid down on a foundation of physics and then even when we think about ourselves our bodies even our consciousness our brains it really all boils down to chemistry and physics it boils down to interactions between atoms and even mechanical properties of our bodies and so even even biology even what we are is built on is built on a foundation of chemistry so this is biology right over here which is built on a foundation of physics which is highly dependent on some of the math that you've been learning your whole life and that you will continue to learn and that fundamental question that you might have said well you know hey why am i learning in this math well one because the math is beautiful but also you'll see that it starts to in almost the most pure way describe the structure of the universe and we're going to see that more and more and more as we go into physics all of this complex phenomena that you see around us whether we're looking at a galaxy or we're looking at ocean waves or we're looking at even biological systems we'll see that a shocking amount of them can start to be described using some fairly elegant mathematics that we can build on and continue to build on simple or elegant mathematics like force is equal to mass times acceleration and we're going to talk about force and acceleration as vector quantities we're gonna think about things like displacement and I'll put it as a vector quantity in and and will soon learn more about what vector and scalar quantities are displacement is equal to velocity times time we'll learn things like acceleration is equal to change in velocity over change in time and what we'll see with even a handful of very simple ideas like this and we'll go into much more depth in future videos you can explain all sorts of complex phenomena and the one thing that I always loved about physics and I don't think it's always fully appreciated sometimes as you start to learn physics you'll see all of these complicated formula all of all of these kind of complicated problems but it's it's super valuable to realize it's all coming from some of these basic ideas some of the things that I just mentioned these ideas we're gonna explore ideas of energy we're going to explore Newton's laws we're going to explain we're going to think about what are all the different types of forces out there and why they might why they might actually exist and its essence it's all about trying to explain the complexity of the universe predict what is going to happen based on simple ideas and that's what physics is all about now when we think of physics it's been studied by humanity for a very very long time in fact I'm sure we don't know who the first physicist the first who the first physicists were but some of the the I guess you could say foundational thinkers in physics are these gentlemen that I have here and this is just a you could kind of say this is some of the most prominent thinkers in physics but I this is by no means a complete list first and foremost we want to include Isaac Newton especially when you start to study physics you're starting to understand the world as Newton understood it he understood hey you know things don't fall to the ground just cuz they always fall to this because that's the way the universe is that that's that's a force that's acting on it and maybe that same force that's causing me to be stuck to my chair right now is what keeps Earth orbiting around the Sun or the moon orbiting around or the moon orbiting around the earth he developed it law of gravitation Newton's laws and we're going to study that as we delve into our basic physics and what we'll see even classical mechanics the the physics that Newton established can explain a large range of phenomena with amazing precision but as we get into the into the early 20th century physics starts to get even more wild as we start to look at the scales of the super-small and we have Max Planck giving us quantum mechanics and then we have Albert Einstein as we start thinking about super fast speeds the speed of light we're as it's an absolute that nothing can travel faster than the speed of light which is which is this mind-boggling thing that that we have this notions of general and special relativity and we start realizing that the universe is is in some ways more bizarre and more mysterious and more fascinating than we ever could have imagined but all of the work even to understand the modern physics of math of Max Planck and Albert Einstein it's based on a lot of the core ideas that were given to us by Isaac Newton even people before Isaac Newton so as you go into your study of physics and and I'm kind of a physicist wannabe I wanted to be a physicist I imagined kind of because it's all about we all wonder why are we here what is the nature of reality what what why do things happen the way they are and these are the questions that physics is attempting to answer and so as you go into your study of physics I want to leave you with some quotes from these three gentlemen so the first two are from Isaac Newton truth is ever to be found in simplicity and not in the multiplicity and the confusion of things and I really wanted to stress this because a lot of times in your studies you might be finding yourself memorizing formulas and and and and vocabulary but that's if you're doing that you're just at the very surface but if you really start to think about it and really start to think about where these things come from it'll come to simpler and simpler and more intuitive ideas and then you are getting closer to the truth now I love the second quote from Isaac Newton I do not know what I may appear to I do not know what I may appear to the world but to myself I seem to have been only like a boy playing on the seashore and diverting myself and now and then finding a smoother pebble or prettier shell than ordinary wilts the great ocean of truth lay all undiscovered before me I like to imagine you know there's so much we even though we think we know so much that we haven't even learned a small fraction of how the universe really is and even a great thinker like Isaac Newton he recognized this he's like hey I'm just kind of dabbling into the into the seashore and picking up a pebble here but there's this vast ocean that I can't even begin to understand you can even imagine alien civilizations that are that are thousands of years ahead of us technologically or is scientifically or even millions of years how they might perceive the reality and they might see us as ants and we are just beginning to scrape the surface of how the world works this is from Max Planck when you change the way you look at things the things you look at change and I find this to be pretty profound because it is true as you study physics you will start to see well most of what we consider to be reality our current understanding is based on these forces but what are these forces and even these things that we think are solid when we go down to the atomic level we see it's mostly empty space and it's really just the interaction of forces that make us think that something is solid or there or or tangible in some when you realize these very tangible things aren't so aren't so tangible after all and at the end of the day the whole world is just a mental model that we have it's in some ways it's a it's a it's a it's a it's illusion that our mind creates so that we can operate inside of it but we're just beginning to understand it and last but not least and there's actually a ton of great quotes from these folks and others but especially Albert Einstein the most beautiful experience we can have is the mysterious it is the fundamentally Oshin that stands at the cradle of true art and true science and I really want you to take this to heart as you study your physics there will be times where we're going to be building our toolkits what's a vector what's a scaler going into some mathematics proving some formulas those are the toolkits but then we're going to try to understand fundamental phenomena how does the universe actually work and if when we start to think about these you don't get a few chills out on your skin a few goose goose bumps and feel that the universe is more mysterious than than you thought then then we're not studying physics the way that we should be studying physics