Hey, Glenn -
Great to have you back. We hope you are finding Scotland ok, and hope you are
finding warm Christian friends there. Things on the List haven't been the same without
your frank and sage postings.
Glenn hat geschrieben:
> We are going to test these ideas, that random sequences can't create
> information. And if genes are like words and sentences and Kenyon and Davis
> claim, then I will show that random sequences CAN create information.
>
> Suppose you are a radioman in the army and are asked to encode instructions for a
> battalion and then transmit it. For years one of the most secure codes was the
>
> letter h and encode it as an i, it will use code 3 for a and encode it as a d and
> code 26 and encode the t as a w. Thus, in the code, hat becomes idw. Since there
> are 26 codes and one must know the code word to decode the message. Messages encoded
> with random keywords are fairly secure. However, as the example below will show,
> there someone trying to crack one of these codes has a real problem.
>
> So, back to the trenches. You have been ordered to encode a message and you
> look select the keyword of the day. It is:
>
> plmoezqkjzlrteavcrcby
>
> which is a random series of letters. You then encode the message
>
> attackthevalleyatdawn
>
> by the method outlined above (spaces are removed from these messages to make
> them more secure I will capitalize the first letter of each decoded message to
> aid the reader in reading them) and it becomes,
>
> pefogjjrnulceiyvvucxl
>
> As you are sending the message, your enemy listens in and collects the above
> sequence. He wants to know what you are going to do, but he doesn't have the
> keyword. So, he starts trying to decipher the message by use of random
> keywords to see if any meaninful sentences come out of your message. He tries
> the keyword
>
> maaktgqkjndrtifdbhkts
>
> and lo and behold, he decodes the message 'DefendTheHillAtSunset'. He runs off
> to tell his commander that the enemy will defend the hill tonight having no
> knowledge that the enemy will attack at dawn. The commander doesn't believe
> the cryptologist and sends him back to try again. This time the cryptologist
> uses the random keyword:dgjgbfrcjhikswlrxpcfs and obtains the message,
> 'MyWifeSpendsMoneyFast'. He knows better than to take that to his commander.
> so he plods on trying dgyuoijekmtcrvspprbdz and wonders if his wife is speaking about
> him as the message now reads, 'MyHusbandIsaNoGoodBum'. Trying dgclajwoluskxifruujqt
> and discovers that the message says, 'MyDogAndCatsHateBaths'. Trying again, he tries
> the keyword wxbzpfrjkqyjxigtvhatu and discovers the message now telling him
> 'ThePresidentHasCancer'. He then tries yamxcjqyubeycafxvbjkh and finds the message
> saying,'RetreatToTheCityAtOne'. Then he tries the keyword, tayolffejizlahywwvsx and
> gets, 'WeHaveOneMoreBazookas'. Trying wxbcgaaagutswxnrsnulthag as a keyword he gets
> 'TheMajorKilledHimself' and trying daugorjrardcneukkfukf he gets
> 'MelissaAndIAreEloping'
>
> Each one of these random strings brought meaning out of the encoded message.
> What this illustrates is that a complex system random events create interesting
> results. The encoding system has a keyword of 21 characters long, a message of 21
> characters and 26 different codes. Thus this has approximately 68 interacting parts.
> The encoding system is complex. The decoding system is equally complex having the
> same 68 interacting parts. And with all this complexity, random sequences create
> meaningful english sentences, just not the sentence you originally intended.
> I must give credit for the first two examples to Simon Singh, The Code Book,
> London: the Fourth Estate, 1999, p. 121-122
(LJ):
Glenn - You are using keywords of nearly the same length and possible complexity as
the short messages you encode. Thus all it takes is to use a computer take a given
message and generate a codeword that is tailored to reproduce the new target
message. You have enough free parameters to do this. So, your new keyword has
been tailored to produce your new message from the old one. It is hardlly a
random sequence.
This is a bit like Dawkins' bamboozle in his "Blind Watchmaker". There he takes
the sentence "Methinks it looks llike a weasel" and essays to reproduce it by
randomly selecting letters, starting with a first letter. He has the computer make
guesses at what the first letter is, and in less than 26 guesses the computer hits
upon the letter M. Since this is what the computer is looking for in the first
letter, it writes down M as the first letter of the new message. (an intelligent
agent has placed the target sentence in the computer.)
Then it goes on to make guesses about the second letter. Soon it hits upon the
letter e, and writes it down and goes on to the third letter. Before long it has
reproduced the entire message "Methinks it looks like a weasel". Since the target
message has 32 letters, and the alphabet 26 letters, it only takes the computer 26 x
32, or 832 guesses to come up with the entire message.
But if each attempt by the computer is a guess at the entire sentence (which is
much more like the biological problem) it takes 26 raised to the 32 power (26^32)
guesses to come up with the target sentence. this is about 10^45 guesses, one
followed by 45 zeros.
All God's best, Larry Johnston
"He has made everything beautiful in its time. He has also set
eternity in the hearts of men" - - Ecclesiastes 3:11, NIV trans
================================================
Lawrence H. Johnston 917 E. 8th st.
professor of physics, emeritus Moscow, Id 83843
University of Idaho (208) 882-2765
http://www.uidaho.edu/~johnston/ =====================
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