1 00:00:00,000 --> 00:00:00,625 - [Voiceover] I could imagine 2 00:00:00,625 --> 00:00:02,514 that even the earliest human beings, 3 00:00:02,514 --> 00:00:04,119 or possibly pre-human beings 4 00:00:04,119 --> 00:00:06,232 had asked themselves the questions, 5 00:00:06,232 --> 00:00:10,052 "Why am I here? What is the nature of reality? 6 00:00:10,052 --> 00:00:13,973 "Why is the universe organized the way that it is?" 7 00:00:13,973 --> 00:00:17,488 And these questions are what we attempt to answer 8 00:00:17,488 --> 00:00:20,071 in the field of physics... 9 00:00:21,131 --> 00:00:22,316 In the field of physics, 10 00:00:22,316 --> 00:00:23,312 which you could view 11 00:00:23,312 --> 00:00:24,612 maybe right after mathematics 12 00:00:24,612 --> 00:00:27,761 as the purest of the sciences. 13 00:00:27,761 --> 00:00:30,646 So you have math, which is very pure, 14 00:00:30,646 --> 00:00:33,592 and then on that foundation of math 15 00:00:33,592 --> 00:00:34,933 you have physics. 16 00:00:34,933 --> 00:00:39,159 And physics really does try to use that mathematics 17 00:00:39,159 --> 00:00:41,048 along with some core ideas 18 00:00:41,048 --> 00:00:43,060 to explain the phenomena, 19 00:00:43,060 --> 00:00:44,238 all the phenomena, 20 00:00:44,238 --> 00:00:45,437 of the universe. 21 00:00:45,437 --> 00:00:47,204 And physicists will the the first to admit 22 00:00:47,204 --> 00:00:49,643 that they are just beginning to understand 23 00:00:49,643 --> 00:00:51,065 the nature of reality, 24 00:00:51,065 --> 00:00:53,076 the nature of everything around us. 25 00:00:53,076 --> 00:00:54,986 Now a lot of times, we think physics 26 00:00:54,986 --> 00:00:59,638 is only limited to things like cosmological phenomena 27 00:00:59,638 --> 00:01:01,731 or getting rockets into space, 28 00:01:01,731 --> 00:01:04,779 or how waves move or building structures. 29 00:01:04,779 --> 00:01:07,379 But physics is the foundation for 30 00:01:07,379 --> 00:01:09,452 all of the other sciences. 31 00:01:09,452 --> 00:01:10,630 When we think about chemistry, 32 00:01:10,630 --> 00:01:12,519 when we think about chemistry, 33 00:01:12,519 --> 00:01:13,678 which is at the end of the day 34 00:01:13,678 --> 00:01:15,384 interactions between atoms, 35 00:01:15,384 --> 00:01:18,858 those interactions are really physics-based interactions. 36 00:01:18,858 --> 00:01:22,820 So chemistry, chemistry is actually laid down 37 00:01:22,820 --> 00:01:25,990 on a foundation of physics. 38 00:01:25,990 --> 00:01:28,062 And then even when we think about ourselves, 39 00:01:28,062 --> 00:01:30,764 our bodies, even our consciousness, our brains, 40 00:01:30,764 --> 00:01:35,437 it really all boils down to chemistry and physics. 41 00:01:35,437 --> 00:01:37,997 It boils down to interactions between atoms 42 00:01:37,997 --> 00:01:40,719 and even mechanical properties of our bodies. 43 00:01:40,719 --> 00:01:43,829 And so even biology, 44 00:01:43,829 --> 00:01:45,596 even what we are, 45 00:01:45,596 --> 00:01:49,943 is built on a foundation of chemistry. 46 00:01:49,943 --> 00:01:53,072 So this is biology right over here, 47 00:01:53,072 --> 00:01:54,901 which is built on a foundation of physics, 48 00:01:54,901 --> 00:01:57,562 which is highly dependent on some of the math 49 00:01:57,562 --> 00:01:59,269 that you've been learning your whole life 50 00:01:59,269 --> 00:02:00,874 and that you will continue to learn. 51 00:02:00,874 --> 00:02:03,007 And that fundamental question that you might have said, 52 00:02:03,007 --> 00:02:04,958 "Well you know, hey, why am I learning this math?" 53 00:02:04,958 --> 00:02:06,461 Well one, 'cause the math is beautiful, 54 00:02:06,461 --> 00:02:08,859 but also you will see that it starts to, 55 00:02:08,859 --> 00:02:10,687 in almost the most pure way, 56 00:02:10,687 --> 00:02:13,044 describe the structure of the universe. 57 00:02:13,044 --> 00:02:15,990 And we're going to see that more and more and more 58 00:02:15,990 --> 00:02:17,473 as we go into physics. 59 00:02:17,473 --> 00:02:19,139 All of this complex phenomena 60 00:02:19,139 --> 00:02:20,033 that you see around us, 61 00:02:20,033 --> 00:02:21,272 whether we're looking at a galaxy 62 00:02:21,272 --> 00:02:22,694 or we're looking at ocean waves, 63 00:02:22,694 --> 00:02:25,600 or we're looking at even biological systems, 64 00:02:25,600 --> 00:02:28,139 we'll see that a shocking amount of them 65 00:02:28,139 --> 00:02:31,695 can start to be described using some fairly elegant 66 00:02:31,695 --> 00:02:33,503 mathematics that we can build on 67 00:02:33,503 --> 00:02:34,702 and continue to build on. 68 00:02:34,702 --> 00:02:36,815 Simple or elegant mathematics 69 00:02:36,815 --> 00:02:40,919 like force is equal to mass times acceleration. 70 00:02:40,919 --> 00:02:43,824 And we're gonna talk about force and acceleration 71 00:02:43,824 --> 00:02:45,246 as vector quantities. 72 00:02:45,246 --> 00:02:48,314 We're gonna think about things like displacement, 73 00:02:48,314 --> 00:02:50,143 and I'll put it as a vector quantity, 74 00:02:50,143 --> 00:02:52,317 and we'll soon learn more about vector 75 00:02:52,317 --> 00:02:53,637 and scalar quantities are. 76 00:02:53,637 --> 00:02:58,005 Displacement is equal to velocity times time. 77 00:02:58,005 --> 00:03:00,321 We'll learn things like accelaration 78 00:03:00,321 --> 00:03:04,385 is equal to change in velocity over change in time. 79 00:03:04,385 --> 00:03:06,985 What we'll see with even a handful 80 00:03:06,985 --> 00:03:09,281 of very simple ideas like this. 81 00:03:09,281 --> 00:03:11,536 We'll go into much more depth in future videos. 82 00:03:11,536 --> 00:03:14,320 You can explain all sorts of complex phenomena. 83 00:03:14,320 --> 00:03:16,819 And the one thing that I always loved about physics, 84 00:03:16,819 --> 00:03:18,627 and I don't think it's always fully appreciated, 85 00:03:18,627 --> 00:03:20,110 sometimes as you start to learn physics, 86 00:03:20,110 --> 00:03:21,979 you'll see all these complicated formula, 87 00:03:21,979 --> 00:03:24,621 all of these kind of complicated problems, 88 00:03:24,621 --> 00:03:27,221 but it's super valuable to realize 89 00:03:27,221 --> 00:03:29,883 it's all coming from some of these basic ideas. 90 00:03:29,883 --> 00:03:31,224 Some of the things that I just mentioned, 91 00:03:31,224 --> 00:03:34,373 these ideas, we're gonna explore ideas of energy. 92 00:03:34,373 --> 00:03:37,400 We're going to explore Newton's laws. 93 00:03:37,400 --> 00:03:39,391 We're going to explain, we're gonna think about 94 00:03:39,391 --> 00:03:41,992 what are the the different types of forces out there, 95 00:03:41,992 --> 00:03:44,978 and why they might, why they might actually exist. 96 00:03:44,978 --> 00:03:48,310 At its essence, it's all about trying to 97 00:03:48,310 --> 00:03:51,033 explain the complexity of the universe, 98 00:03:51,033 --> 00:03:52,739 predict what is going to happen 99 00:03:52,739 --> 00:03:55,685 based on simple ideas. 100 00:03:55,685 --> 00:03:58,022 And that's what physics is all about. 101 00:03:58,022 --> 00:03:59,708 Now when we think of physics, 102 00:03:59,708 --> 00:04:02,979 it's been studied by humanity for a very, very long time. 103 00:04:02,979 --> 00:04:04,036 In fact, I'm sure we don't know 104 00:04:04,036 --> 00:04:07,733 who the first physicists were. 105 00:04:07,733 --> 00:04:08,883 But some of the, 106 00:04:08,883 --> 00:04:11,321 I guess you could say foundational thinkers 107 00:04:11,321 --> 00:04:14,490 in physics are these gentlemen that I have here. 108 00:04:14,490 --> 00:04:15,343 And this is just a... 109 00:04:15,343 --> 00:04:16,603 You could kind of say 110 00:04:16,603 --> 00:04:19,569 this is some of the most prominent thinkers in physics, 111 00:04:19,569 --> 00:04:21,886 but this is by no means a complete list. 112 00:04:21,886 --> 00:04:25,238 First and foremost, we'd wanna include Isaac Newton. 113 00:04:25,238 --> 00:04:27,838 Especially when you start to study physics, 114 00:04:27,838 --> 00:04:30,219 you're starting to understand the world 115 00:04:30,219 --> 00:04:31,621 as Newton understood it. 116 00:04:31,621 --> 00:04:32,881 He understood, "Hey, you know, 117 00:04:32,881 --> 00:04:34,344 "things don't fall to the ground 118 00:04:34,344 --> 00:04:35,664 "just 'cause they always fall to, 119 00:04:35,664 --> 00:04:37,208 "just 'cause that's the way the universe is. 120 00:04:37,208 --> 00:04:39,748 "That's a force that's acting on it, 121 00:04:39,748 --> 00:04:41,820 "and maybe that same force that's causing me 122 00:04:41,820 --> 00:04:44,137 "to be stuck to my chair right now 123 00:04:44,137 --> 00:04:46,839 "is what keeps Earth orbiting around the Sun 124 00:04:46,839 --> 00:04:50,882 "or the moon orbiting around the Earth." 125 00:04:50,882 --> 00:04:53,096 He developed Law of Gravitation, 126 00:04:53,096 --> 00:04:54,844 Newton's Laws, and we're going to study that 127 00:04:54,844 --> 00:04:57,627 as we delve into our basic physics. 128 00:04:57,627 --> 00:04:58,623 And what we'll see, 129 00:04:58,623 --> 00:05:00,004 even classical mechanics, 130 00:05:00,004 --> 00:05:03,052 the physics that Newton established, 131 00:05:03,052 --> 00:05:05,977 can explain a large range of phenomena 132 00:05:05,977 --> 00:05:07,278 with amazing precision. 133 00:05:07,278 --> 00:05:10,325 But as we get into the early 20th century, 134 00:05:10,325 --> 00:05:12,398 physics starts to get even more wild 135 00:05:12,398 --> 00:05:14,393 as we start to look at the scales 136 00:05:14,393 --> 00:05:15,592 of the super small, 137 00:05:15,592 --> 00:05:18,842 and we have Max Planck giving us quantum mechanics, 138 00:05:18,842 --> 00:05:20,712 and then we have Albert Einstein 139 00:05:20,712 --> 00:05:23,840 as we start thinking about super fast speeds, 140 00:05:23,840 --> 00:05:26,380 the speed of light, and we realize that's an absolute. 141 00:05:26,380 --> 00:05:29,102 That nothing can travel faster than the speed of light, 142 00:05:29,102 --> 00:05:31,378 which is this mind-boggling thing 143 00:05:31,378 --> 00:05:33,674 that we have these notions 144 00:05:33,674 --> 00:05:35,787 of general and special relativity, 145 00:05:35,787 --> 00:05:37,697 and we start realizing that the universe 146 00:05:37,697 --> 00:05:40,521 is in some ways more bizarre, and more mysterious, 147 00:05:40,521 --> 00:05:43,548 and more fascinating than we ever could have imagined. 148 00:05:43,548 --> 00:05:46,413 But all of the work, even to understand the modern physics 149 00:05:46,413 --> 00:05:49,135 of Max Planck and Albert Einstein, 150 00:05:49,135 --> 00:05:52,203 it's based on a lot of the core ideas 151 00:05:52,203 --> 00:05:54,133 that were given to us by Isaac Newton, 152 00:05:54,133 --> 00:05:56,226 even people before Isaac Newton. 153 00:05:56,226 --> 00:05:58,725 So as you go into your study of physics, 154 00:05:58,725 --> 00:06:01,671 and I'm kind of a physicist wannabe. 155 00:06:01,671 --> 00:06:03,479 I wanted to be a physicist. 156 00:06:03,479 --> 00:06:04,677 I imagined kind of, 157 00:06:04,677 --> 00:06:06,933 'cause it's all about, we all wonder, 158 00:06:06,933 --> 00:06:07,969 why are we here? 159 00:06:07,969 --> 00:06:09,777 What is the nature of reality? 160 00:06:09,777 --> 00:06:12,378 Why do things happen the way they are? 161 00:06:12,378 --> 00:06:14,979 And these are the questions that physics 162 00:06:14,979 --> 00:06:16,624 is attempting to answer. 163 00:06:16,624 --> 00:06:19,225 And so as you go into your study of physics, 164 00:06:19,225 --> 00:06:21,074 I wanna leave you with some quotes 165 00:06:21,074 --> 00:06:22,801 from these three gentlemen. 166 00:06:22,801 --> 00:06:25,401 So the first two are from Isaac Newton. 167 00:06:25,401 --> 00:06:29,018 "Truth is ever to be found in simplicity, 168 00:06:29,018 --> 00:06:32,594 "and not in the multiplicity and the confusion of things." 169 00:06:32,594 --> 00:06:34,300 And I really wanted to stress this, 170 00:06:34,300 --> 00:06:35,661 because a lot of times in your studies, 171 00:06:35,661 --> 00:06:37,795 you might be finding yourself memorizing formulas 172 00:06:37,795 --> 00:06:41,208 and vocabulary, but that's, 173 00:06:41,208 --> 00:06:43,768 if you're doing that, you're just at the very surface. 174 00:06:43,768 --> 00:06:45,759 But if you really start to think about it, 175 00:06:45,759 --> 00:06:48,055 really start to think about where these things come from, 176 00:06:48,055 --> 00:06:51,285 it'll come to simpler and simpler and more intuitive ideas. 177 00:06:51,285 --> 00:06:54,577 And then, you are getting closer to the truth. 178 00:06:54,577 --> 00:06:57,380 Now, I love this second quote from Isaac Newton. 179 00:06:57,380 --> 00:07:00,265 "I do not know what I may appear to... 180 00:07:00,265 --> 00:07:03,171 "I do not know what I may appear to the world, 181 00:07:03,171 --> 00:07:07,234 "but to myself, I seem to have been only like a boy 182 00:07:07,234 --> 00:07:08,534 "playing on the seashore, 183 00:07:08,534 --> 00:07:11,033 "and diverting myself in now and then 184 00:07:11,033 --> 00:07:12,699 "finding a smoother pebble 185 00:07:12,699 --> 00:07:14,426 "or prettier shell than ordinary, 186 00:07:14,426 --> 00:07:17,352 "whilst the great ocean of truth 187 00:07:17,352 --> 00:07:20,521 "lay all undiscovered before me." 188 00:07:20,521 --> 00:07:22,126 I like to imagine there's so much, 189 00:07:22,126 --> 00:07:24,321 we, even though we think we know so much, 190 00:07:24,321 --> 00:07:27,571 that we haven't even learned a small fraction 191 00:07:27,571 --> 00:07:29,258 of how the universe really is. 192 00:07:29,258 --> 00:07:31,594 And even a great thinker like Isaac Newton, 193 00:07:31,594 --> 00:07:32,630 he recognized this. 194 00:07:32,630 --> 00:07:34,113 He's like, "Hey, I'm just kind of dabbling 195 00:07:34,113 --> 00:07:36,572 "into the seashore and picking up a pebble there, 196 00:07:36,572 --> 00:07:37,750 "but there's this vast ocean 197 00:07:37,750 --> 00:07:39,558 "that I can't even begin to understand." 198 00:07:39,558 --> 00:07:41,488 You can even imagine alien civilizations 199 00:07:41,488 --> 00:07:43,845 that are thousands of years ahead of us 200 00:07:43,845 --> 00:07:45,918 technologically or scientifically 201 00:07:45,918 --> 00:07:47,157 or even millions of years, 202 00:07:47,157 --> 00:07:49,067 how they might perceive the reality, 203 00:07:49,067 --> 00:07:50,408 and they might see us as ants 204 00:07:50,408 --> 00:07:51,789 in that we are just beginning 205 00:07:51,789 --> 00:07:54,309 to scrape the surface of how the world works. 206 00:07:55,749 --> 00:07:56,836 This is from Max Planck. 207 00:07:56,836 --> 00:07:59,173 "When you change the way you look at things, 208 00:07:59,173 --> 00:08:01,286 "the things you look at change." 209 00:08:01,286 --> 00:08:03,947 And I find this to be pretty profound, 210 00:08:03,947 --> 00:08:04,739 because it is true. 211 00:08:04,739 --> 00:08:05,674 As you study physics, 212 00:08:05,674 --> 00:08:06,588 you will start to see, whoa, 213 00:08:06,588 --> 00:08:08,234 most of what we consider to be reality, 214 00:08:08,234 --> 00:08:09,717 our current understanding is based 215 00:08:09,717 --> 00:08:11,789 on these forces, but what are these forces? 216 00:08:11,789 --> 00:08:14,004 And even these things that we think are solid, 217 00:08:14,004 --> 00:08:15,650 when we go down to the atomic level, 218 00:08:15,650 --> 00:08:17,112 we see it's mostly empty space 219 00:08:17,112 --> 00:08:18,819 and it's really just the interaction of forces 220 00:08:18,819 --> 00:08:20,790 that make us think that something 221 00:08:20,790 --> 00:08:23,594 is solid or there or tangible is some way. 222 00:08:23,594 --> 00:08:24,934 And you realize these very tangible things 223 00:08:24,934 --> 00:08:27,149 aren't so tangible after all. 224 00:08:27,149 --> 00:08:28,774 At the end of the day, the whole world 225 00:08:28,774 --> 00:08:31,477 is just a mental model that we have. 226 00:08:31,477 --> 00:08:32,308 In some ways, 227 00:08:32,308 --> 00:08:34,970 it's an illusion 228 00:08:34,971 --> 00:08:37,815 that our mind creates so that we can operate inside of it. 229 00:08:37,815 --> 00:08:40,313 But we're just beginning to understand it. 230 00:08:40,313 --> 00:08:42,041 And last but not least, 231 00:08:42,041 --> 00:08:43,464 and there's actually a ton of great quotes 232 00:08:43,464 --> 00:08:44,825 from these folks and others, 233 00:08:44,825 --> 00:08:46,450 but especially Albert Einstein. 234 00:08:46,450 --> 00:08:48,340 "The most beautiful experience 235 00:08:48,340 --> 00:08:50,453 "we can have is the mysterious. 236 00:08:50,453 --> 00:08:53,399 "It is the fundamental emotion that stands 237 00:08:53,399 --> 00:08:56,446 "at the cradle of true art and true science." 238 00:08:56,446 --> 00:08:58,762 And I really want you to take this to heart 239 00:08:58,762 --> 00:09:00,123 as you study your physics. 240 00:09:00,123 --> 00:09:02,155 There will be times where we're going 241 00:09:02,155 --> 00:09:03,435 to be building our tool kits. 242 00:09:03,435 --> 00:09:04,146 What's a vector? 243 00:09:04,146 --> 00:09:04,776 What's a scalar? 244 00:09:04,776 --> 00:09:06,280 Going into some mathematics, 245 00:09:06,280 --> 00:09:07,702 proving some formulas. 246 00:09:07,702 --> 00:09:09,165 Those are the tool kits, 247 00:09:09,165 --> 00:09:10,648 but then we're gonna try to understand 248 00:09:10,648 --> 00:09:12,050 fundamental phenomena. 249 00:09:12,050 --> 00:09:14,244 How does the universe actually work? 250 00:09:14,244 --> 00:09:16,397 And if when we start to think about these, 251 00:09:16,397 --> 00:09:18,856 you don't get a few chills on your skin, 252 00:09:18,856 --> 00:09:21,538 a few goosebumps, and feel that the universe 253 00:09:21,538 --> 00:09:23,569 is more mysterious than you thought, 254 00:09:23,569 --> 00:09:25,419 then we're not studying physics 255 00:09:25,419 --> 00:00:00,000 the say that we should be studying physics.