Friday, November 24, 2006

*** Decoding the Universe by Charles Siefe

An excellent book that describes information theory in a down to earth fashion, and surprisingly enlightens you to the fact that information may be at the very heart of how quantum mechanics and cosmology affect the entire universe. The book also does an excellent job of explaining away the Schrodinger’s Cat paradox, along with the Einsteinian pole in a barn relativity paradox. You’ll never be puzzled again about such bizarre phenomena. -Ben

During WW2, the war in the Pacific hinged on one missing piece of information - Where was AF? AF was the Japanese code name for an American target for which the Japanese were planning a major offensive… The head of the Navy's cryptography ordered the base at Midway to transmit a phony request for help stating that the water distillery had been damaged and the base was nearly out of water. Knowing that the Japanese would be eavesdropping, Navy intelligence soon picked up the signals of 'AF is short of water'… The battle of Midway was decisively won by the US, and this information was crucial to setup the plans for that victory. p6

A sentence in English always has more information than you need to decipher it. This redundancy is easy to see. J-st tr- t- r—d th-s s-nt-nc- . p11

A std 3 rotor enigma machine used by the Nazi’s from WW2 could be configured in more than 3x10^114… If every atom in atom in the universe were an Enigma machine, and each were trying a million billion combos per second from the beginning of the universe, they would only have been able to try 1% of all the possible configurations. So how did the small cadre of codebreakers [one of which was Alan Turing] at Bletchley Park, England, break the unbreakable code? The enigma would never leave a letter unchanged; therefore an encrypted ‘E’ could be any letter except an ‘E’, yielding a tiny bit of information about the message. Also the predictability of weather reports and language offered other forms of redundancy… Eventually, they got so good at it, they could crack a new coding scheme in a matter of hours. P19

Shannon realized that a question with N possible outcomes can be answered with a string of logN bits – you need only logN bits of info to distinguish among N possibilities. To distinguish among 4 outcomes, you need only 2 bits; 8 outcomes, 3 bits… I could therefore tell you that I have picked out an atom somewhere in the universe. Since there are 10^80 atoms in the universe, and log10^80 is about 266, it would take only 266 properly chosen yes/no answers to find it. P66

A linguist can figure out who won the battle of Hastings [1066, William the Conqueror, and all mate]. Look at the words for foodstuffs. Beef comes from a French word – boeuf, while cow comes from Old English. Mutton is French for – mouton, while sheep is Old English. Pork, French for – porc; pig, English. The English speaking serfs, who lost the battle, tended the animals. The victorious French nobility, ate them. This information is preserved in our language nearly 1000 years after this event. P114

Keep watching (measuring actually) a radioactive atomic nucleus over and over and you can prevent it from decaying. Repeated measurements can prevent nuclear decay. This effect is known as the Quantum Zeno effect. If you start with a pure state 100% 0 & 0% 1 (superposition between 0&1 with a 100% probability of 0), the nucleus is unbroken. If you measure the nucleus quickly, by bouncing a photon off of it, you’re nearly guaranteed to measure it in the 0 state because it wouldn’t have had much time to evolve a superposition away from the pure state; it would now be 99.999% 0 and .001% 1. But the act of measurement destroys the superposition and resets it to the pure state of 100% 0. Thus you can measure it again, and reset it again. If you do this over and over, it will never decay! P198

1 comment:

Anonymous said...

This is a horrible book.