Summary
The computer has been hailed as the greatest innovation of the 20th century, and there is no denying that these technological marvels have dramatically changed our everyday lives. They can fly airplanes and spaceships, route millions of phone calls simultaneously, and play chess with the world's greatest players. But how limitless is the future for the computer? Will computers one day be truly intelligent, make medical diagnoses, run companies, compose music, and fall in love? In Computers Ltd., David Harel, the best-selling author of Algorithmics, illuminates one of the most fundamental yet under-reported facets of computers--their inherent limitations. Looking only at the bad news that is proven, discussing limitations that no amounts of hardware, software, talent, or resources can overcome, the book presents a disturbing and provocative view of computing at the start of the 21st century. Harel takes us on a fascinating tour that touches on everything from tiling problems and monkey puzzles to Monte Carlo algorithms and quantum computing, showing just how far from perfect computers are, while shattering some of the many claims made for these machines. He concludes that though we may strive for bigger and better things in computing, we need to be realistic: computers are not omnipotent--far from it. Their limits are real and here to stay. Based on hard facts, mathematically proven and indisputable, Computers Ltd. offers a vividly written and often amusing look at the shape of the future.
Author Biography
David Harel is William Sussman Professor of Mathematics at The Weizmann Institute of Science, in Israel. One of the world's leading computer scientists, he is the author of the critically acclaimed Algorithmics, which has sold more than 100,000 copies worldwide.
Table of Contents
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1 | (27) |
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2 | (3) |
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5 | (2) |
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7 | (2) |
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9 | (1) |
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What do algorithms solve? |
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10 | (5) |
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Isn't our setup too simplistic? |
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15 | (1) |
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Solving algorithmic problems |
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16 | (2) |
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18 | (3) |
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21 | (5) |
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26 | (1) |
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27 | (32) |
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Finite problems are solvable |
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29 | (1) |
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30 | (3) |
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33 | (3) |
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Elementary computing devices |
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36 | (4) |
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40 | (2) |
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42 | (4) |
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46 | (2) |
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48 | (2) |
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50 | (3) |
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Nothing about computation can be computed! |
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53 | (1) |
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Some problems are even worse |
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54 | (5) |
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sometimes we can't afford to do it |
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59 | (32) |
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Resources: time and memory space |
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60 | (1) |
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61 | (4) |
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65 | (4) |
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69 | (1) |
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69 | (4) |
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The good, the bad, and the ugly |
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73 | (5) |
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78 | (4) |
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82 | (3) |
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Problems that are even harder |
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85 | (3) |
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Unreasonable memory requirements |
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88 | (3) |
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Sometimes we just don't know |
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91 | (28) |
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92 | (3) |
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95 | (2) |
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97 | (3) |
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100 | (2) |
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102 | (2) |
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104 | (2) |
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106 | (3) |
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Standing or falling together |
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109 | (2) |
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The great mystery: is P equal to NP? |
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111 | (2) |
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113 | (2) |
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115 | (4) |
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119 | (38) |
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Parallelism, or joining forces |
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121 | (3) |
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Can parallelism eliminate the bad news? |
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124 | (5) |
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Randomization, or tossing coins |
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129 | (3) |
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More on Monte Carlo algorithms |
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132 | (2) |
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134 | (2) |
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Randomized primality testing |
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136 | (4) |
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Can randomization eliminate the bad news? |
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140 | (1) |
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Can computers simulate true randomness? |
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141 | (2) |
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143 | (3) |
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146 | (5) |
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Can there be aquantum computer? |
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151 | (2) |
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153 | (4) |
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157 | (32) |
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158 | (3) |
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161 | (4) |
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165 | (3) |
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Can this be made to work? |
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168 | (2) |
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170 | (3) |
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173 | (4) |
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177 | (3) |
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180 | (6) |
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On millionaires, ballots, and more |
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186 | (3) |
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Can we ourselves do any better? |
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189 | (24) |
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Algorithmic intelligence? |
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191 | (1) |
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192 | (4) |
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196 | (3) |
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199 | (5) |
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204 | (4) |
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Understanding natural language |
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208 | (5) |
| Postramble |
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213 | (2) |
| Index |
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215 | |