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"Science is the source of all other knowledge"
"Mathematics is about numbers and physics is all about mathematical functions"

all physics equation

stephen hawking

crazy Quantum mechanics + beautiful relativity = Universe (including us?)

"All that we know from common sense are necessary mistakeno or erroneous.. "

Theory of everything

Theory of everything is the ultimate theory of physics , that should describe all physical aspects and occurrences in a consistent manner. Such theory , if it is found, needs to unify all fundamental forces of nature. String theory is the best candidate for theory of everything. It is a theoretical framework that have merged quantum mechanics with theory of relativity. According to string theory universe has nine space dimensions and one time dimension. All the dimensions other than three are curled up and tiny so that we can not directly perceive them. Besides this crucial feature, the principles of string theory say that what appears to be elementary particles are tiny vibrating pieces of strings. Somehow if we can work out resonant or vibrational pattern of the piece of string we will be able to explain the observed properties of the elementary particles. The conclusion is that the universe is a cosmic symphony of strings resonating through ten dimensional hyperspace. What are we ? We are nothing but the melodies. We are nothing but cosmic music played on the same cosmic strings or membranes.
General theory of relativity theory of quanta

General theory of relativity + theory of quanta = Everything

General advice

Readers from all over the world , have you a feeling that you are bad at mathematics? Do not fear mathematics. Once I was also a victim. You can now conquer mathematics easily. The secret is behind logic. Logical ideas alone can define mathematics. I will state russell's paradox first. If you understand this you can safely assume that you have a good mathematical sense .
Suppose R is a set of all sets that are not members of themselves. Now is this set R is a member of itself or not? If it is a member of itself then it is one of the sets which are not members of themseves. So it is not member of itself. And if this set R is not member of itself then by definition it is a member of itself. So in either way we come to a contradiction!
This was Russell famous paradox. All mathematics are basically logical deductions. You can follow my website for more logical analysis of mathematics.

"Universe is not what it seems to be"


The main purpose of this website is to give some basic ideas of classical physics, quantum mechanics, relativity and quantum field theory for those who wants to become a science major or philosopher in science. Theories are at the heart of physical sciences and mathematics. Here most of the major and interesting theories of physics have been discussed. Those who want to understand popular science books will get help from this website. Some electrical and electronics engineering concepts have also been given for undergraduates of electrical engineering. This website is not supposed to include everything. Those who are very curious to understand scientific theories and spacetime physics in somewhat non technical way, will find this website very usefull. So far a little subject matters have been included. In the future more and more topics will be added. Many topics of Mathematics and its applications are also demonstrated in a simple manner. I have already said, all physics is interpreted by mathematical functions. The principle aim will be to justify this claim.

Theories are basically mathematical descriptions of natural phenomena. A theory is like a boat. How well the boat floats gives the soundness of the theory. The better the boat floats, the better the theory is. As long as a theory is able to describe particular phenomena , it is accepted as valid. But it can never be taken as irrefutable and absolute. For a better theory can replace the old one. Such is the case with Newton's universal law of gravitation

There is good news for those who are electrical engineers. The good news is that you guys can be physicists easily than others. If you read this website attentively you will be able to find deep connection between electrical engineering and theoretical physics . Study this website and follow its pages whenever you can.

Theoretical physics,

Quantum Field Theory

Feynman's sum over histories   |   S-matrix   !   quantum field theory

Theory of relativity

Relativity made simple   |   Special theory of relativity   |   General theory of relativity   |   Tensor calculus  |   Hamiltonian mechanics   |   Field equation  |   Perihelion of mercury|   Geodesic distance

Quantum mechanics

Schrodinger equation   |   Matrix mechanics   |  Dirac equation

heisenberg's equation of motion
In quantum mechanics operators are replacements for classical quantities like position and momentum. They are some kind of functions too.
all the physics in one equation (excluding string theory)
all physics equation

This is the equation which is derived in analogy with Feynman's path integral equation.
paradox of physics
There are seven ideas that shook the universe. These are
1. Newtonian mechanics
2. Energy and entropy
3. relativity
3. quantum theory
4. conservation principles
5. copernican astronomy
6. symmetries
7. Theory of everything
"we are all here to do what we are all here to do"

Newtonian mechanics made it possible to develop the first mathematical model of the universe. It was a great revolution in science. Everything in science is founded upon principles of newtonian mechanics. It is hard to imagine anything which does not correspond to Newton's law. Quantum mechanics and relativity are developed to account for the phenomena which classical newtonian mechanics fails to explain. But in the limit both theories reduce to newtonian framework. Application of Newton's law is almost everywhere from rocket science to automobile engineering. We have developed an innate sense of the principles of newtonian mechanics in us. We move and throw objects as if we know the position in advance.
On the other hand we can not predict the outcome of quantum mechanics experiment precisely. Principles of quantum mechanics violate our common sense. It is developed using logic and mathematics which defy our intuition. Suppose you throw an electron in the wall and on the wall there are several objects placed. Then there is always some chance that the electron will hit those objects at the same time. This is the kind of weirdness that our commonsense can not grasp. There are other bizzare consequences of quantum mechanics like entanglement and quantum tunnelling. According to Quantum mechanics spooky action at a distance is possible. This faster than light communication had disturbed Einstein too much. According to theory of relativity nothing can travel faster than light and causality is not violated. Quantum mechanics have certainly made many phenomena non-causal. The state of affairs in quantum world can be described with the following example:
if we adopt the theory of radiation, the atom seems to live a "self contained life" - " the world forgotten by the world forgot". But the atom sometimes involves in parcel-post activity. That is to say, it can give a parcel of energy to a postman or it can receive one from him. The postman(who is not a teetotaller) who receives the parcel sways from side to side. The bigger the parcel is, the faster he sways. He runs at the same speed every time whether the parcel is big or small. The postman is the only link between the world of atom and the outside world.

Giving to others is a great virtue....

"I know everything is in the mind but mind is a very powerful thing"

Free will

Another matter that is of great debate is the problem of free will. According to principles of classical mechanics everything is predictable. Our actions are not governed by us. Every will and volition have previous causes and that cause in turns has another cause. Thus we certainly do not have any free will. But in quantum mechanical world nothing is predictable with absolute certainly and we might possess free will after all. We have freedom to make our own decision. According to classical physics we have only one of two alternatives (yes or no) in our mind. Our choice is predetermined with yes or no option. But according to quantum principles we have both yes and no options, which exist simultaneously in our mind. Thus Quantum mechanics has rescued free will from drowning.
The phenomena of having both yes and no states in our mind is called the principle of quantum superposition. Scientists have been able to find the exact location of the brain where this quantum superposition seems to take place. This part of the brain is called microtubules. There is a close connection between our consciousness and quantum mechanics. Both are mysterious and thus both may be the same.

"Everything in physics has an equation.."

quantum tunneling

quantum tunneling

the Matrix

Have you ever seen the movie matrix? if you like science you must watch this. This movie tells us that our world is in a computer simulation or inside a matrix. what if our world is a complex computer program. We are nothing but the strings of binary digits 1 and 0. It is hard to believe but many scientists believe it to be so. According to the simulation theory even our consciousness is simulated by computer program. I do not know whether this theory is right or wrong but such theory has many advantages.

"Simplicity is beauty.." equations of physics

Some of the revolutionary equations of physics in one package

equations of physics

"what is mind never matters and what is matter never mind.."
"We are the children of atoms, so understand the atom if you try to understand the universe"

This is our universe , look for yourself

theoretical physics topics

The fist term in the lagrangian of the second equation describes force carriers like photons. The second term describes quarks , leptons and their interactions. The third term describes higg's particles. The fourth term including h.c(hermitian conjugate) make quark and leptons massive.

"Knowledge is power"

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Electrical and electronics Engineering

Integrated Electronics  |   Power Engineering   |   Telecommunication   |   Control System Engineering   |   Electronics  |   Fundamentals of EEE  |   Digital signal processing  |   Digital Filters |   Maxwell equations  |   Differential equation and calculus

"God is a great mathematician"


Mathematics is the language of nature. It is hard to define mathematics . In general it is the study of change, numbers and shapes. Mathematics consists of various branches like arithmetic, geometry, topology, calculus and many more. Science can not progress without mathematics. This is so obvious fact that needs not be mentioned. Mathematics , in a certain sense , an exact science. We all accept the mathematical theorems and truth because we can prove those. we all accept 2+2 = 4. Mathematics is always flawless. That is what mathematicians thought every time. But Kurt Godel gave a death blow to mathematics by claiming that no mathematical system is complete. Axiomatic systems are necessary incomplete. That means there will always be some statement within the system , whose truth can not be proven using the system. This was very frustrating idea for the mathematical society and no one has yet been able to refute Godel's claim. This is known as the Godel's first incompleteness theorem. This theorem is kind of related to the "liar paradox" of usual language. Suppose there is a sentence " he is lying". Now if the sentence is true then when he says that he is lying , he is indeed lying. That means he is telling the truth. The sentence's truth can not be determined as we come to a contradictory situation. There are other similar paradoxes explained here.
"Mathematics has a better sense than the common sense"
There is hardly any branch of engineering and science where mathematics does not apply. Mathematics is a sense you never have. So nobody is gifted with mathematical ability. You can not be good at it without practising it. But it seems surprising that our mind which is so well organized can not adapt with mathematics everytime. Or may be it is a wrong idea.
"pure mathematics is a poetry of logical ideas"
Without speaking about numbers the importance of mathematics can not be described. To describe numbers or define numbers we need to know how to count. To count , in turn, will need three steps : 1) the idea of many-ness 2) one-to-one mapping and 3) sequentially speak or say the number words
First we need to have the idea of many-ness. We need to answer the question of how many? How many objects do we a collection have? Then we map each objects to other objects with one-to-one relation.
Mapping: mapping is assigning each element of a set to exactly one element of another set.
When we assign an element , say our finger to each element of a collection , we speak one for one finger , two for two fingers and so on to last one which will be the cardinal number of our collection or set. Then we give a symbol for the number if we like. This symbol will represent that particular number.
The invention of calculus has changed the world. Calculus was invented by Leibniz and Newton at the same time although there is priority dispute about who invented it first. Application of calculus is everywhere. Where there is change there is calculus. Where there is curvature there is calculus. Both the theory of relativity and quantum mechanics were developed using calculus. Everybody knows that the idea of calculus is rooted in the notion of limit. When we speak about something approaching another one or some point approaching another point , the notion of limit appears. There is precise definition of limit. You can think of it as a scheme to manipulate infinite number of small quantities. We know we can sum infinite number of terms in a geometric series, which converges. Same thing happens in case of limit. One quantity converges to another and in the end they become equal. This is the core idea of limit and calculus.
Real numbers are all the numbers that can be traced on number line. It includes both rational and irrational numbers. Real number line contains no gap or it is continuous. Irrational number was defined in order to make the real number line complete. It is the set R. It is extended from - (infinity) to +(infinity) including zero. Real numbers are also called measurable numbers. It includes the set of integers too. Calculus is certainly established using the concepts of real numbers. Cantor first proved that the set of real numbers is non denumerable. It can not not put in one-to-one correspondence with natural numbers(1,2, 3, 4, 5,6 ......). Real numbers has cardinality 2^(ℵ0) , which is called cantorian continuum. Cantor also proposed that there is no set which cardinality lies strictly between that and ℵ(0). This is called continuum hypotheses. These two infinite numbers of continuum hypotheses play exactly the same role as integers 0 and 1. There is no integer in between 0 and 1. Cantor knew that this was the case but he never came up with a proof. Later Kurt Godel showed that this hypotheses is consistent with axiomatic set theory.
Pythagoras law has made a great impact on science and mathematics. This law holds for any right angle triangle in Euclidean geometry. The law says square of the hypotenuse is equal to sum of squares of other two sides. This law not only bears the fact of geometry but also laid the foundation of many scientific theories like theory of relativity and electromagnetism. Pythagoras law also states that there is a 3-tuple of integers which satisfy it. In another words there are infinite number of solutions of Pythagoras law. More specifically , there are infinite solutions for x, y and z in integers which represent the three sides of any right angle triangle. This brings us to Fermet's last theorem. The theorem states that there are no solution for x, y and z in integers for power greater or equal to 3. Proof of Farmet's last theorem took much time to be discovered. This proof involves number theory.
Gauss was perhaps one of the greatest mathematicians of all time. He was first to study the curved surfaces. What we call plane is particular cases of 2-dimensional surfaces or manifolds. In physics he contributed also. We all know Gauss's law of electromagnetism. Gauss was very talented in his early childhood. One day his teachers asked everybody in his class to add all the numbers from 1 to 100. Gauss calculated it more quickly than others within seconds. He just did it by adding two numbers and multiplying it by 50. How ? 50 pairs of numbers have the same summation like 1+99 =100 , 2+ 98 = 100, and so on.. So the total sum is 50*100 = 5000. Gauss also developed many theorems which are still very usefull.
"Mathematics gives you wings"
Roger Penrose is the world's leading mathematical physicist. He collaborated with Hawking and proved that time had a beginning. The proof concerns the postulates of the theory of relativity. He is a mathematician too. He is specialized in recreational mathematics. He makes many complicated mathematical problems seem easy by graphical representation. Mathematics, according to him, has certain platonic existence. There are three kinds of worlds :one is physical world, second is mental world and the third is platonic world. Mathematical objects and forms exist in platonic world. Mathematical objects or forms are numbers, triangles, circles, sets and many more. There is no perfect circle in real world. We can not see perfect flat space anywhere in the universe. This kind of pure mathematical or geometric objects exist only in the platonic realm.
Our mental world consists of all our thoughts and abstract percepts. It has no connection to physical reality. Our mental world contains particular or percepts. Universals are certain concepts can exist without our mind. Mental world does not necessarily make logic and mathematics dependent on it.
Physical world is the materialistic world that we inhabit. It is the whole universe or multiverse-as we may call it.

So what is the most complicated topic in mathematics? Is it topology or geometry or calculus? or is it linear algebra or statistics? It is none. Mathematics builds upon itself. If you want to understand calculus you need to understand limit and functions. If you need to understand topology you need to understand set theory. It is like a chain. If one link is missing the whole system is broken. We do not understand mathematics because of these missing links. Lot of things is dependent on definitions. We can define something when there are notions which have a certain relation to some term , which is itself one of the said notions. Why is physics hard to understand? Physics has lots of notation and symbols which scares us away. You can talk about general relativity. In relativity all boils down to 21 numbers that Riemann curvature tensor assigns at each event in spacetime. In classical electromagnetism at each event in spacetime there are 16 numbers that electromagnetic field tensor assigns. How does these numbers creep in? I guess you have to have some ideas about those theories. Take another example of quantum field theory. This theory treats particles as excitation of the fields. Everything in QFT can be thought as perturbation in an infinite number of sets of infinite number of tiny springs. Particles come from energy that the fields represent. In quantum electrodynamics there are three functions which give three different numbers describing all interaction between matter and radiation. I guesss I have to say that Pythagoras was right all along when he said that numbers rule the universe. If you know only calculus well and have some basic ideas of linear algebra you can understand a lot of advanced theoretical physics theories.

"If the multiverse theory is correct then there is someone exactly like you (doppleganger) which is reading this sentence in another universe!!"
"When you got nothing , you got nothing to loose.."

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Chaos Theory

Some systems are very sensitive to initial conditions. A small change in the initial conditions can create a huge disturbances in the system. Such system is known as chaotic system. For example, a flapping of the butterfly wings in New York can cause a hurricane in London. This is known as butterfly effect. Mathematics of such system is very complicated. To analyze chaotic system chaos theory has been developed. The dynamics governing such chaotic system is also very complex. We can not predict the behaviour of such system as exact initial condition is always unknown.

"Things you own end up owning you"


Fractals are geometric objects. Fractal is self-similar object which pattern is never ending - appearing again and again. For example a snowflake is a fractal like object which contains similar parts within it. If one looks closer and closer at this kind of fractal like object he will see the same structure over and over again. Fractals are a great subject matter for mathematicians. We can see fractals almost everywhere. These are in the leaves of trees, in the painting of an artist and in many other things. This kind of structures certainly can reveal many secret about our universe. Fractal can be defined using scales. Fractals are scale invariant. That is these are the same whether you look into smaller parts or bigger parts.
Mandelbrot set is an example of fractal like structure. The equation of Mandelbrot set is the iteration map :

mandelbrot set

"Mathematics may not teach us how to add love or subtract hate but it ensures every problem has a solution..."

One electron universe

One electron universe is a concept or idea which tells that there are only one electron in the universe. What we observe to be different particles is really one electron going back and forth through time. The world lines traced by a single electron make a twisted structure like a knot in spacetime. Any slice through time represent the single electron at different locations. Positron can be viewed as electron going from future to past in space.
Richard Feynman qouted something which represents this fact of electron going back and forth in time :
" I know why all the electrons have identical mass and charge because they are all the same electron. "
Electron is a point mass which have negative charge. Electrons are the singularities in electromagnetic field. That is to say, they have infinite divergence. What it means need a careful study of Maxwell's equations.

"If an idea does not seem absurd at the first time, then there is no hope for it.."

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"The universe is the ultimate free launch.."

If you can't beat me then join me...

"If you want to reveal the secret of the universe , think in terms of energy, frequency and vibration.."

Duffing equation for harmonic oscillators

The equation below contains some interesting terms. First one is the inertia which is the force of Newtonian mechanics. The seconds term is the damping force which is proportional to the velocity. The third term is spring force which is proportional to position of spring . The fourth is the non-linear term in x^3 . The right hand side contains a variable force.
Duffing equation
What does an equation mean ? Any equation is plausibility of any natural phenomena. According to Ramanujan " An equation has no meaning unless it expresses the mind of God"

Black Hole

The space-time diagram of black hole describes the event horizon and singularity. At the event horizon the light-cones tip over and falls into singularity. The diagram actually describes the sapcetime collapsing of a star when it forms a black hole. When the star shrinks the matter inside the star shrinks too and the density starts to increase.

black hole dynamics

At some point the density becomes very extreme and event horizon forms. Light wave can no longer escape the horizon. This phenomena is depicted in the diagram above. Our earth can be turned into a black hole of it can be squeezed into a sufficient small size object. Time comes to a halt at the event horizon of the black hole. To an outside observer this time dilation fact will be apparent. Space time diagram above also suggests space and time come to a star.

Miscellaneous pages
Algebra   |  coordinate geometry   |  Topology for dummies   |  Symmetry   |   Bertrand Russell philosophy   |  Sir issac newton   |  Topology for dummies   |  Albert Einstein  |   Artificial intelligence   |  Leonhard Euler   |  Carl Friedrich Gauss   |  Number theory   |   what is science   |  complex analysis   |  perihelion of mercury  |   string theory explained  |  Calculus for dummies   |  Medical Science definition   |  Mathematical universe
Chamok Hasan Mathematics  |  Complex analysis
quantum mechanics and elementary physics |  Mathematics (Advanced)

"The best thing about science is that you can apply it to your life"
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"whatever happened, happened for a reason and could not have happened in any other way"

psycho analysis

Sigmund Freud was perhaps one of the best experimentalists or clinical psychologists. He used to study and experiment with his patients. He coined the term psychoanalysis. Psycho analysis is the study of mind or it is the theory of how activities and interaction of our mental life is described . Phyche means mind. Psychoanalysis , in general, is concerned with how human behaves. Psycho analysis is based on three apparatus :one is ego, the second is Id, and the third is superego. Id is the uncoordinated instinctual trends, superhero is the critical and moralistic act. Ego plays the role of mediating between id and superego. Freud based the model of psyche with these three apparatus. In terms of these concepts he interpreted the process of dreaming. He also claimed that all sexuality is psycho-sexuality. His theories have impacted modern psychology to a great degree. He concluded some strange consequences from his theories. For example we certainly enjoy pleasure of anal sex from defecation. A child develops sexuality when it sucks its mother's nipple and so on. Full explanation of psychoanalysis needs much space but the basic ideas are those explained above.

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Physics of the impossible

Michio kaku have tried to explain all the paranormal activities in the context of science. These are telekinesis , telepathy, mind reading , psychokinesis and many others. We see all these in sci-fi Hollywood movies every now and then. But are these phenomena real or scientific? There is no direct relationship between these and science. Science like to explain stuff in terms of causal relationships. As far as causality is concerned there are no hope for these kinds of phenomena to be true. In science we have explanation and evidences. Paranormal activities have no explanation otherwise these were not called paranormal in the first place.
That does not mean we give up. May be, some future science will explain or make these phenomena possible.

All equations
"Without electricity we would not think, your heart would not beat..."

Academic courses concerning electrical and electronics engineering

Science of telecommunication and electronic engineering is very impressive branch of education now a days. Power electronics and semiconductor devices are some of the sub fields of electrical and electronics engineering. The courses and subjects of it are huge in numbers and vary from universities to universities. Some of the courses of computer science are Boolean algebra, data structures, microprocessor design, automata theory, complexity theory and many types of computer programming languages. The courses of electrical and electronics engineering are divided into two main fields : one is telecommunication and other is power engineering. Each field has number of courses to be studied by students of electrical and electronics engineering. Some of the courses have prerequisite courses to be passed in order to take the former courses. All courses are distributed among a number of semesters during certain interval of time. This gives student sufficient time to study and understand the concepts of the subjects. It is imperative that students of EEE understand the basics of dc and ac circuit. Transient analysis plays an important role in circuit analysis. Transient state is the interval during which system changes its behavior from one state to another state. During transient state system output may be very oscillatory and thus it can be unstable. It is the time a system takes to reach steady state. The time taken is called transient time. The relationship between voltage and current that system gives during transient state are called the transient response. More details will be studied when we analyze dc and ac R-L-C circuit and control system engineering. Elementary circuit theory utilize Thevenin's theorem and Norton theorem. These two theorems or laws play an important role in simplifying linear circuits.

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Supersymmetry and superpartners

The guage symmetry describes whole of particle physics and it is the crucial property of standard model. Standard model is considered the most ugliest theory in physics although it has underlying symmetry principles. Physicist now seek for more abstract and hihger order symmetry properties that can desrcibe relationships of all the fundamental elementary particles and messanger particles altogether. Messenger particles are force carrying particles like photons, gluons, w bosons and others. This symmetry will be called supersymmetry. More specifically, this supersymerry involves more subtle spin angular momentum of sub-atomic particles. All particles will have superpartners. The unification of electromagnetic force, strong nuclear force and weak nuclear force needs supersymmetry to be incorporated. The experimental result confirms that the straight of the three forces do not meet at a point as the distance scale increases. That is something missing in the usual theories, which can be overcome by supersymmetry.

I like to finish with anthropic principle which states that universe is the way it is because we are here to observe it. It is a cosmological principle. The universe is constrained by the necessity to allow human existence. Have you ever have a feeling of why all the things are specifically happening to you? The answer is the anthropic principle.

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Million dollar problems


This is a problem related to computer science. Computer solves problems according to rules and instructions. There are two different types of problems that should be addressed by a computer program. First type includes all those problems that can be solved in polynomial time. That is to say as the complexity of the problem increases the computatioinal time increases polynomially ( powers of a variable as the input to the algorithm). These kinds of problems are called P -type problems. For some questions, there is no known way to find an answer quickly, but if one is given information showing what the answer is, it is possible to verify the answer quickly. The class of questions for which an answer can be verified in polynomial time is called NP. That is , they are classified as NP.
An answer to the P = NP question would determine whether problems that can be verified in polynomial time can also be solved in polynomial time. If it turned out that P ≠ NP, it would mean that there are problems in NP that are harder to compute than to verify: they could not be solved in polynomial time, but the answer could be verified in polynomial time. This is the million dollar problem in computer science. If you prove this apparent dilemma of P VS NP , you will win million dollars from Clay Mathematics Institute.

Riemann hypothesis

In mathematics, the Riemann hypothesis is a conjecture that the Riemann zeta function (ζ(s))has its zeros only at the negative even integers and complex numbers with real part . Many consider it to be the most important unsolved problem in pure mathematics (Bombieri 2000). It is of great interest in number theory because it implies results about the distribution of prime numbers. It was proposed by Bernhard Riemann (1859), after whom it is named.
If you can prove this hypothesis, you will get a million dollars from the same institute.
riemann hypothesis

Reference materials:

Law of thermodynamics
A briefer history of time by S. Hawking
A brief history of time by S. Hawking
Quantum mechanics
Grand Design by Stephen Hawking
Higher Engineering Mathematics ( PDFDrive.com ).pdf
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