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Sample Copy. Not for Distribution.
i
Information Theory
of The Cosmos
Sample Copy. Not for Distribution.
ii
Publishing-in-support-of,
EDUCREATION PUBLISHING
RZ 94, Sector - 6, Dwarka, New Delhi - 110075 Shubham Vihar, Mangla, Bilaspur, Chhattisgarh - 495001
Website: www.educreation.in
________________________________________________________________
© Copyright, 2018, Raghunath Tiruvaipati
All rights reserved. No part of this book may be reproduced, stored in a retrieval system, or transmitted, in any form by any means, electronic, mechanical, magnetic, optical, chemical, manual, photocopying, recording or otherwise, without the prior written consent of its writer.
ISBN: 978-1-5457-1880-3
Price: ` 1,614.00
The opinions/ contents expressed in this book are solely of the authors and do not represent the opinions/ standings/ thoughts of Educreation or the Editors . The book is released by using the services of self-publishing house.
Printed in India
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iii
Information Theory
of The Cosmos How The New Science of Information Changes Our
Understanding And Perception of The Universe
Raghunath Tiruvaipati
EDUCREATION PUBLISHING (Since 2011)
www.educreation.in
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iv
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v
To My Mother
And Father
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vi
Content List
Sr. No. Content Page
Prologue vii
1. Cryptography 1
2. Thermodynamics 12
3. Information theory 19
4. Genetic Code 40
5. Cosmology 133
6. Life on Earth 165
7. Astronomy 225
8. Relativity 272
9. Quantum Computing 297
10. Quantum Entanglement & Quantum
Tunneling
307
Epilogue 321
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vii
Prologue ______________________________________________________
Information theory is a relatively new paradigm even though
scientific research about it began in 1948 itself. it is synthesized
from information revolution which is the greatest technological
advancement in the 21st century. Computers , hard drives and
internet have revolutionized the world. In 20th century itself,
Communications technology has advanced from wired to wire-
less. Computers and communication technology are only tiny
aspects of the information theory that we are going to talk
about in this book. It deals not only with the way that machines
like computers, cell-phones work , but also with objects on the
scale from quantum level such as electron, photons, atoms
etc.. to astronomical level such as planets, suns, galaxies ,
black holes and the universe itself. Its rules determine the life
course of the universe and the entire cosmos as well.
Information theory took birth or rather uncovered in the 20th
century which has changed the world dramatically.
Information theory spans across thermo dynamics, theory
of relativity , quantum mechanics, genetics, cosmology,
astronomy and quantum computing. So I will touch upon all of
these topics in this book.
Thermo dynamics - which explains about the working of
engines, exchange of heat energy and motion of atoms is an
information theory.
Theory of relativity – which explains about the large
objects moving at extremely high speeds (almost at speed of
light) and the influence on them by gravity is also an
information theory.
Quantum mechanics – which explains about the domain of
atoms and sub-atomic particles is also an information theory.
Genetics – genes are literally information-carrying bio-devices. So genetics is also an information theory. We will discuss it later.
Astronomy – all the galaxies, stars, planets contain a huge
amount of information in the form of electromagnetic waves.
And through these waves, they influence with each other. So
astronomy is also a information theory.
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viii
Information is much more than what we assume about it
(that is, simply some content) and co-relates all the above
mentioned theories together.
Information theory changes our perception of the world
radically because information is not something that is non-
objective. Everything in the universe is constructed from
information. So it is a rather important aspect of energy and
matter. It is physical and can be quantized and measured which
is contrary to our usual thinking. It is influenced by several
physical laws which prescribe how it can be manipulated,
transferred, copied, erased or destroyed. And everything in the
universe must accord to the laws of the information theory.
As a result of the information theory, communications and
computers have been transformed in a huge way. The laws of
the information theory influences not only the data in a
computer (data - bits and bytes which are ultimately the
electrical voltage),but also codes and communication channels.
They govern the way how the sub-atomic particles (electrons,
quarks,etc..) behave . Even life obeys these laws and so does
the entire universe.
Everything in the universe including life-forms on our earth
are bundled with information. The DNA molecule in the living
beings contains a huge amount of information in the form of
genes which works like a blue print for the construction of the
organism. Our body and mind processes trillions of bits of
information each second unconsciously. Every particle , be it a
photon, or an electron or a quark or an atom, is teeming with
information in the form of spin, charge, size, electron
configuration and weight which can be processed and
transformed in energy transactions (chemical reactions). All the
stars and galaxies in the universe are emitting information in
the form of electro-magnetic waves which is spreading all over
the cosmos.
Information seems to be the driving force behind the
physical structure of the universe. It appears to solve the big
scientific questions such as the origin of life, the black holes,
the relativity theory and the quantum mechanics. The
information theory is leading to a way to answer some of the
most profound issues about the universe in the scientific
community.
*****
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Information Theory of the Cosmos
1
Cryptography ______________________________________________________
Information should be transferred from place to place or from
person to person in a secure way. The most ancient way to
secure information is to use cryptography in the form of codes
and ciphers. They must be secure enough so that when
somebody taps the message, they must not be able to make it
out.
Even though cryptography has been in place since time
immemorial, the codes and ciphers were not secure enough.
Somebody who has a little bit of knowledge about ciphers can
break the encrypted message. Yet, people had to rely on these
weak codes and ciphers to communicate sensitive information.
Regardless of how well the information is encrypted, there is a
chance for it to decrypted as it is passing from place to place.
In the digital world, information is communicated in bits. To a
sniffer, every bit is very much tangible and susceptible.
As said earlier, information is very much real and solid just
as other properties of a particle. We can not see the spin,
charge and electronic configuration of an atom directly but they
are real. Similarly information is equally real. It can be
quantized, evaluated and tampered with. Information has to
travel physically from sender to receiver just like any other
physical object. It can travel through a telephone line or a cable
or wireless mechanism. Of course there is quantum
entanglement in which two particles are entangled with each
other over incredibly vast distance and still communicate with
each other instantly. But the mechanism behind it is yet to be
found out by the physicists.
Because information is a real entity, it can be displaced or
sniffed through just like any other thing. But information must
be propagated from place to place and from person to person
to be of any value.
Now a days, encryption technology has advanced so much.
A cryptographer has to design the cipher such that the
information passes from the sender to the receiver without
anybody sniffing that information in-between. The information
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Raghunath Tiruvaipati
2
essence of the encrypted message should not be perceived by
anybody. Similarly, a decrypter tries to make out information
from a random mixture of letter and symbols. He can break the
encrypted message if the cipher is weak.
That the information is tangible and quantized is the main
principle of the information theory. The science of cryptography
will give an idea how information is tangible and how it must be
propagated from place to place. One of the most important
properties of information is its redundancy. If you grasp
redundancy ,you can know why information is real and tangible.
When we receive an information, for example something
like ―this rose is beautiful‖, what is happening is that your brain
is taking a series of words in the visual cortex and processing
them to get the meaning of the message. when you read
something on a paper, what is happening is you are receiving a
series of symbols and try to grasp the meaning of that
message. Your brain receives a set of symbols that say ―this
rose is beautiful‖ in the visual cortex and processes those
symbols until its meaning is understood. All this happens at the
sub-conscious level. This sub-conscious process is vital to our
ability to use language. Redundancy is makes a message easy
to grasp.
When a sentence is distorted , we can still decipher it. That
is because of redundancy. Every sentence in any language is
quite redundant and has more information than you need to
make out its meaning. For example, take the sentence ―j-st s—
th-s‖ . it is quite distorted because all the vowels in the
sentence are removed. How ever we can still decipher it and
extract its meaning.
Redundancy is very useful. It allows for a sentence to be
understood easily even if the sentence is distorted somewhat.
Syntax and lexicographic rules create redundancy in all
languages. When your are amidst a crowd, It is redundancy
that helps us understand words spoken by others. Our brains
unconsciously processes the words according to lexicographic
rules.
Let us discuss the information redundancy in terms of
computer science , communication theory and we will also
discuss the enigma machine and the turing machine , two
famous machines in history used for breaking the cryptgrams.
In computer science, information redundancy adds extra
information to tolerate communication faults. Mainly two kinds
of codes are used for fault tolerance : error detecting codes &
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Information Theory of the Cosmos
3
error correcting codes. These codes are used mostly in
communication channels and computing science. Code of length
n is a set of n-tuples satisfying some well-defined set of rules.
Binary codes use only 0 and 1.
From the ―Mathematical theory of information‖ by
C.E.Shannon, the definition of information is as follows:
Definition1: information is the minimum number of bits,
necessary to encode the subject message.
Definition2: information is the length of the shortest possible
code, used to transport the message.
Example1: a report about rainfall , indicating weather there is
rainfall or no rainfall alternatives, has information of 1 bit
Rainfall code
Yes 1
No 0
Example2: information about a measurement scale- a more
detailed one answering two simple yes/no questions: is it tall or
short? And is it smooth or rough? The information content of
the below table is 2 bits.
Tall? Smooth? code
Yes Yes 11
Yes No 10
No Yes 01
No No 00
If the message is longer than is necessary, that means if it
is longer than information of the message, the code contains
redundancy. It is the 2-logarithm of the quotient between the
code length and the information of the message.
Redundancy=log2 (code length / information)
Redundancy can never be negative. It can be zero. when
the code is as short as it can be (Code length is identical to the
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Raghunath Tiruvaipati
4
INFORMATION, which is seldom the case). It is 1.0, when the
code length is 2 x
INFORMATION. The REDUNDANCY present in different
messages is eventually a compromise between
efficiency concerns and security issues. Example:
Measurement scale code
Tall & smooth TS
Tall & rough TR
Short & smooth SS
Short & rough SR
The INFORMATION did not change and still amounts to 2
bits. The code length however increased from 2 to 16 bits.The
REDUNDANCY of this code is log2(16/2) = log2(8) = 3.
Error detection and correction is one of the main concerns
while transmitting information and it is characterized by the
number of bits that can be corrected.
Double-bit detecting code can detect two single-bit errors
Single-bit detecting code can detect one single-bit error.
There is something called Hamming distance which gives
the measure of error detection/correction capabilities of a code.
HAMMING DISTANCE
Hamming distance is the number of bit positions in which two
n-tuples differ.
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Information Theory of the Cosmos
5
Code distance
Code distance is the minimum Hamming distance between any
two distinct codewords.
Information and redundancy complement each other. When you deprive all the redundancy from a message, the left over is the information. Compression programs take this factor into account when downsizing the files.
The efficiency of a compression program is determined by
the percentage of redundancy that it removes from the file. No
matter how efficient the program is, there will be some data
that is at the heart of the message. This chunk of information
has to pass from sender to receiver.
Often cryptographers try to remove as much redundancy
as possible. If he designs a good cipher, the message will be
encrypted efficiently and it can be deciphered only by the
intended recipient. Anybody who sniffs at the packet of
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Raghunath Tiruvaipati
6
information while it is passing from sender to receiver will not
be able to make out the meaning of it. Often cipher exposes
data because of redundancy.
The Enigma machine is a piece of hardware invented by a
german and used by britain‘s code breakers as a way of
deciphering german signals traffic during second world war.
A Turing machine is a hypothetical machine thought of by
the mathematician Alan Turing in 1936. Despite its simplicity,
the machine can simulate ANY computer algorithm, no matter
how complicated it is!
Above is a very simple representation of a Turing machine.
It consists of an infinitely-long tape which acts like the memory
in a typical computer, or any other form of data storage. The
squares on the tape are usually blank at the start and can be
written with symbols. In this case, the machine can only
process the symbols 0 and 1 and " " (blank), and is thus said to
be a 3-symbol Turing machine.
At any one time, the machine has a head which is
positioned over one of the squares on the tape. With this head,
the machine can perform three very basic operations:
Read the symbol on the square under the head.
Edit the symbol by writing a new symbol or erasing it.
Move the tape left of right by one square so that the
machine can read and edit the symbol on a neighbouring
square.
A simple demonstration
As a trivial example to demonstrate these operations, let's try
printing the symbols "1 1 0" on an initially blank tape:
First, we write a 1 on the square under the head:
Next, we move the tape left by one square:
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Information Theory of the Cosmos
7
Now, write a 1 on the new square under the head:
We then move the tape left by one square again:
Finally, write a 0 and that's it!
A simple program
With the symbols "1 1 0" printed on the tape, let's attempt to
convert the 1s to 0s and vice versa. This is called bit inversion,
since 1s and 0s are bits in binary. This can be done by passing
the following instructions to the Turing machine, utilising the
machine's reading capabilities to decide its subsequent
operations on its own. These instructions make up a simple
program.
Symbol read Write instruction Move instruction
Blank None None
0 Write 1 Move tape to the right
1 Write 0 Move tape to the right
The machine will first read the symbol under the head,
write a new symbol accordingly, then move the tape left or
right as instructed, before repeating the read-write-move
sequence again.
Let's see what this program does to our tape from the
previous end point of the instructions:
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