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← (h) TROM - 1.1 Science

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Showing Revision 10 created 09/30/2015 by Andrés de Jesús Soto Elizondo.

  1. Can you hear me?
  2. Yes,
  3. I think you can hear me now,
  4. but you don't see me.
  5. That's because you have ears.
  6. If you close your eyes and reach for the screen
  7. you will know it's there.
  8. You feel it through your skin.
  9. If you have not been allowed to touch it,
  10. at least you can smell it,
  11. and after the hot plastic smell
  12. you will realize that your monitor has to be there.
  13. Luckily, you have a nose.
  14. But, what if you taste it?
  15. Well, it would be more difficult,
  16. but eventually you'll taste the plastic,
  17. because you have a tongue.
  18. You understand the world around you,
  19. I mean, everything that is around you,
  20. through those five senses.
  21. If you have ears,
  22. you can hear.
  23. If you have eyes,
  24. you can see.
  25. Through your skin,
  26. you can feel.
  27. The tongue will help you taste,
  28. and if you have a nose, you can smell.
  29. Eyes, ears, nose, tongue and skin are the "tools"
  30. with which you were born.
  31. Tools that help you understand
    the world around you.
  32. But, how did you know all this?
  33. Just because you noticed?
  34. And how did we divide them into five senses?
  35. The answer is science.
  36. Because the world is so complicated
  37. we use science to discover and define.
  38. But, what is science?
  39. "Investigation and study of nature
  40. by observation and reasoning."
  41. or "the sum of all knowledge
  42. obtained through research."
  43. Basically a sum of tests, numbers and letters,
  44. which, all together can define.
  45. But how?
  46. Most people recognize marks as values,
  47. and the best known groups are
    letters and numbers.
  48. They are inventions which help us
  49. to understand our environment.
  50. To better understand how these marks
  51. came into existence
  52. let's see a brief history of mathematics.
  53. Human beings, from our earliest beginnings,
  54. have searched for solutions to basic problems.
  55. Building homes, measuring space,
  56. keeping track of seasons and counting objects.
  57. Over thirty thousand years ago
  58. early paleolithic people
  59. kept track of the passing seasons
  60. and the changes of weather for planting.
  61. To represent the passing of time
  62. they carved tally marks on cave walls
  63. or slashed tallies on bones, wood or stone.
  64. Each tally stood for one.
  65. But this system was awkward
  66. when it came to large amounts.
  67. So symbols were eventually created
  68. that stood for groups of objects.
  69. Sumerian clay stones have been found
  70. that date to the fourth millennium BC.
  71. A small clay column was used for one,
  72. a clay ball was used for ten,
  73. and a large cone stood for sixty.
  74. Written records from around 3300 BC show
  75. that Babylonians inscribed amounts
  76. on clay tablets with a reed.
  77. They used a nail shape for ones,
  78. and a V on its side for tens,
  79. combining these symbols to write other numbers.
  80. For example,
  81. Babylonians wrote the number 19 as...
  82. The ancient Egyptians used objects
  83. from their everyday life as symbols.
  84. A rod stood for one, a cattle hobble was ten,
  85. a coiled rope was a hundred,
  86. a lotus flower was a thousand and so on.
  87. The number 19 was a cattle hobble and nine rods.
  88. The early Romans created a number system
  89. that we still see today.
  90. Along with other symbols
  91. they used an X for ten and an I for one.
  92. By the middle ages
  93. Romans were putting the I to the right of the X
  94. for eleven and to the left for nine.
  95. So they wrote 19 as XIX.
  96. All these creative number systems
  97. show groups of objects, as well as individual objects.
  98. Some of the oldest human counting systems
  99. rely on fingers and toes.
  100. So they were based on ones, fivers, tens and twenties.
  101. The Zulu word for six means
  102. to take the thumb of the right hand.
  103. Meaning that all the fingers on the left hand
  104. had been added up and the other thumb was needed.
  105. Other systems evolved from commerce.
  106. The Yoruba, in Nigeria,
  107. used cowry shells as currency
  108. and developed an amazingly complex number system.
  109. It was based on 20s
  110. and on the operations of multiplication,
  111. subtraction and addition.
  112. For example:
  113. they thought of 45 as (3 x 20) - 10 - 5.
  114. Knots tied in cords and strings were used
  115. for recording amounts by many cultures,
  116. like the Persians.
  117. The Incas used a more refined version
  118. called the "quipu":
  119. A thick cord held horizontally
  120. from which hung knotted string.
  121. The kind of knot the Incas used
  122. along with the length and color of the cord
  123. represented 1s, 10s, and 100s.
  124. In today's world almost every industrial culture
  125. uses the numeral 0 through 9.
  126. But these symbols weren't invented
  127. until the third century BC in India
  128. and it took another 800 years
  129. for the idea of 0 with place value to be constructed.
  130. This big idea
  131. dramatically changed the face of mathematics.
  132. We humans have always shared with one another.
  133. When early cultures shared their food and water
  134. or wanted to divide their land
  135. in ways that were fair and equal,
  136. fractions gradually emerged
  137. as symbols for these fair share situations.
  138. The ancient Egyptians used unit fractions.
  139. Fractions where the numerator is 1,
  140. like 1/2, 1/3 and 1/5,
  141. and would add and halve these fractions.
  142. If they wanted to divide three loaves of bread equally
  143. among five family members,
  144. they'd first divide the first and second loaves
  145. into thirds.
  146. Then, they'd divide the third loaf into fifths.
  147. Finally, they'd take the remaining one third
  148. from the second loaf and divide that into five pieces.
  149. They wrote this as 1/3, 1/5, 1/15.
  150. Today we would represent this sharing
  151. with the fraction 3/5.
  152. 3/5 of a loaf for each person,
  153. or 3 loaves divided by 5 people.
  154. The Sumerians and early Babylonians
  155. invented a number system of fractions
  156. based on 60, that we still use 4000 years later.
  157. Our days have 60 minute hours
  158. and 60 second minutes,
  159. and our circles encompass 360 degrees.
  160. Chinese societies used an abacus
  161. with a system based on 10s, although it had no 0.
  162. An early form of decimal fractions
  163. came from the abacus.
  164. For example:
  165. 3/5 would be 6 out of 10 on an abacus
  166. The Chinese lovingly named the numerator "the son"
  167. and the denominator "the mother".
  168. It wasn't until the 12th century
  169. that common fractions,
  170. with the bar notation that we use today,
  171. were invented.
  172. Even then, these fractions weren't widely used
  173. until the renaissance period, only 500 years ago.
  174. Throughout history every culture around the globe
  175. has created inventive ways to calculate.
  176. To solve a problem, say... 12 x 15,
  177. early Russian peasants
  178. used a system of doubling and halving.
  179. When an odd number halved resulted in a fraction,
  180. they rounded down,
  181. then they added the factors
  182. associated with the odd multipliers.
  183. Ancient Egyptians relied on a doubling procedure
  184. until they produced enough groups.
  185. Then they added these groups to find the answer.
  186. Across Europe and Asia, during the middle ages,
  187. the abacus was the handheld calculator of its day.
  188. But only very few people knew how to use it,
  189. usually wealthy merchants and money lenders.
  190. By simply moving beads that each had place value
  191. an abacus was a highly efficient way to compute.
  192. Then, the great Arab mathematician al-KhwÄrizmÄŤ
  193. introduced the Hindu Arabic numerals 0 through 9,
  194. into North America and Europe
  195. and created new procedures for computation.
  196. These algorithms could be written onto paper.
  197. Over the centuries learning the algorithms
  198. became the whole mark of an education
  199. as students were taught to compute
  200. long columns of figures,
  201. borrow and carry,
  202. and do long division efficiently and reliably.
  203. They could now keep records of these procedures
  204. and check results.
  205. Today complex calculations
  206. are done with a handheld calculator.
  207. This means students need the ability
  208. to check the reasonableness of the answer
  209. and to have a rich repertoire
  210. of mental math strategies to do that.
  211. Most simpler computations like 12 x 15
  212. can be solved mentally using a variety of strategies.
  213. As we journey through the rich
  214. and vibrant history of mathematics
  215. we can see how ideas and creations
  216. grew out of our very human need
  217. to solve the problems in our everyday lives.
  218. Through time, the mathematical explorations
  219. of men and women from around the globe,
  220. have given us fascinating lenses
  221. that help us to mathematically view
  222. and make sense of our world.
  223. Science is the collection of facts
  224. arrived at by defining what we observe
  225. and running tests to discover.
  226. Mathematics, chemistry, and physics represent fixed
  227. languages which are not subject to interpretation.
  228. Languages used to describe what we observe and
  229. to test those observations in order to prove them.
  230. Think of DNA,
  231. cells, galaxies,
  232. fruits,
  233. laptops,
  234. air conditioning.
  235. Think about cars,
  236. food,
  237. houses,
  238. fauna,
  239. flora.
  240. Think about atoms,
  241. body parts,
  242. climate,
  243. or the clothes you wear.
  244. And realize that everything is defined,
  245. or created
  246. by science.
  247. To understand the whole concept of science,
  248. you should know what a scientific theory is:
  249. "A scientific theory
  250. comprises a collection of concepts,
  251. including abstractions of observable phenomena,
  252. expressed as quantifiable properties,
  253. together with rules (called scientific laws)
  254. that express relationships
  255. between observations of such concepts."
  256. A scientific theory is constructed to conform to
  257. available empirical data about such observations,
  258. and is put forth as a principle or body of principles
  259. for explaining a class of phenomena.
  260. A scientific theory is totally different
  261. from any other theory,
  262. it is the most probable variant
  263. resulting from recent discoveries.
  264. Science is the best tool ever devised
  265. for understanding how the world works.
  266. Science is a very human form of knowledge.
  267. We are always at the brink of the known.
  268. Science is a collaborative enterprise
  269. spanning new generations.
  270. We remember those who prepared the way,
  271. seeing through them also.
  272. If you're scientifically literate
  273. the world looks very different to you,
  274. and that understanding empowers you.
  275. There's real poetry in the real world.
  276. Science is the poetry of reality.
  277. We can do science, and with it,
  278. we can improve our lives.
  279. There's real poetry in the real world.
  280. Science is the poetry of reality.
  281. The story of humans is the story of ideas
  282. that shine light into dark corners.
  283. Scientists love mysteries, they love not knowing.
  284. They don't feel frightened by not knowing things.
  285. I think it's much more interesting.
  286. There's a larger universal reality
  287. of which we are all a part.
  288. The further we probe into the universe,
  289. the more remarkable are the discoveries we make.
  290. The quest for the truth, in and of itself,
  291. is a story that's filled with insights.
  292. There's real poetry in the real world.
  293. Science is the poetry of reality.
  294. We can do science, and with it,
  295. we can improve our lives.
  296. There's real poetry in the real world.
  297. Science is the poetry of reality.
  298. The story of humans is the story of ideas
  299. that shine light into dark corners.
  300. From our lonely point in the cosmos,
  301. we have through the power of thought
  302. been able to peer back to a brief moment
  303. after the beginning of the universe.
  304. I think that science
  305. changes the way your mind works.
  306. To think a little more deeply about things.
  307. Science replaces private prejudice
  308. with publicly verifiable evidence.
  309. There's real poetry in the real world.
  310. Science is the poetry of reality.
  311. We can do science, and with it,
  312. we can improve our lives.
  313. Science is a great tool
  314. for understanding the surrounding world
  315. think of it as a magnifying glass
  316. through which you can see
  317. the reality of the world.