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Newton&Einstein&Hawking!10

By Jeanette White,2014-06-19 00:32
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Newton&Einstein&Hawking!10 Newton&Einstein&Hawking!10

    Newton &Einstein &Hawking’s

    Universe

    HONGJIELIANG Sir

    Isaac Newton P R S M P (25 December 1642 – 20 March 1727 [NS:4

    [ 1] January1643–31March1727])wasan English

     p h y s i c i s t, m a t he m a t i c ia n, a s t r o n o m e r, n a t u r a l

     ph il osophe r, al c h e mi s t, and t he o l og i a n, who has been "considered by

    [ 7]many to be the greatest and most influential s c i e n t i s t who ever lived."

     Hismonograph P h il o s oph i æ Na t ura li s P r i n c i p ia

     M a t h em a t i c a, published in 1687, lays the foundations for most of

     c las s i c a l m e c h a n i c s. In this work, Newton described un i v e r s a l

     g r a v i t a t i o n and t h e t h r ee l a w s of m o t i on, which dominated the

    scientific view of the physical un i v e r se for the next three centuries. Newton showed that the motions of objects on E a rt h and of

     c e l e s t ia l bodies are governed by the same set of natural laws, by

    demonstrating the consistency between K ep l e r ' s l a w s of p la n e t ar y m o t i on

    and his theory of gravitation, thus removing the last doubts about

     he li o c e n tr i sm and advancing the S c i e n t ific R e v o l u t i o n .

     ht t p : / / en . w i k i ped ia .o r g / w i k i/ I ss a c_N e w t o n

    Albert Einstein (14 March 1879 – 18 April 1955) was a

    German t heo r e t i c a l phys i c i st who developed the

    theory of g ene r a l r e la t i v i ty, effecting a revolution in ph y s i cs.

    For this achievement, Einstein is often regarded as the father of

    [ 2] [ 3] While best known for his ma ss ene rg y m ode r n ph y s i cs.

    2 equ i v al en c e formula E = mc(which has been dubbed "the

    [ 4] world's most famous equation"),he received the 1 92 1 N obel

     P r iz e i n P hys i c s "for his services to theoretical physics, and especially for his discovery of the law of the ph oto e l e ctr i c

    [ 5] e ff e ct".The latter was pivotal in establishing qu a n t um

     t heo r y within physics.

    Near the beginning of his career, Einstein thought that N e w t on ia n m e c h a n i c s was no longer enough to

    reconcile the laws of c las s i c a l m e c h a n i c s with the

    laws of

    the e l e ctr o ma g ne t i c fi e l d. This led to the development of his spe c ia l t heo r y of r e la t i v i t y. He realized, however, that the

    principle of relativity could also be extended to gr a v i t a t i on al

     fi e l d s, and with his subsequent theory of gravitation in 1916, he published a paper on the g ene r a l t heo r y of r e la t i v i t y. He

    continued to deal with problems of s t a t i s t i c a l

     m e c h a n i c s and qu a n t um t heo ry, which led to his explanations

    of p a rt i c le t heo r y and the m ot i o n o f m o l e c u l e s . He also

    investigated the thermal properties of light which laid the foundation of the ph o t on theory of light. In 1917,

    Einstein applied the general theory of relativity to model the

    [ 6]structure of the un i ve r se as a whole.

     ht t p: / / e n. w i k ip e d i a. o rg / w i ki / A l be r t _ E i n st e in

Stephen William Hawking, CH, CBE, FRS, FR SA (born 8

    January

    1942) is a British t heo r e t i c a l phys i c i s t, co s m o l og i s t, and

    author. His key scientific works to date have included

    providing, with R o g er P en r os e , t he o r e m s regarding g r a v i t a t i on a l

     s i n g u la r i t i es in the framework of g en e r a l r e la t i v i ty, and the theoretical prediction that b la c k ho l es should emit radiation, which is today known as H a wk i ng r a d ia t i on (or sometimes as Bekenstein–Hawking radiation).

    He is an H o n or ar y F e ll o w of the Roy a l S oc i e t y o f A rts, a

    lifetime member of the P on t ifi c a l A c a de m y o f S c i en c es, and in 2009 was awarded the P r es i den t ia l M ed a l of Fr eedo m , the

    highest civilian award in the United States. Hawking was the

     Lu c a s ia n Pr o f ess o r of M a t he ma t i c s at the University of Cambridge between 1979 and

    2009. Subsequently, he became research director at the university's Centre for Theoretical Cosmology.Hawking has a m o t or neu r o ne d i s e a se related to am yotro p h i c

     la t e r a l s c l e r os i s, a condition that has progressed over the years. He is now almost completely paralysed and communicates through a spee c h g ene r a t i ng dev i c e . He has been

    married twice and has three children. Hawking has achieved success with works of popu la r s c i en c e in which he discusses his

    own theories and cosmology in general; these include A B r i ef

     H i s t o r y of T i m e, which stayed on the British Sund a y T im es

    best-sellers list for a record-breaking 237 weeks.

     ht t p : / / en . w i k i ped ia .o r g / w i k i/ S t ephen _ H a wk i ng

    These three physicists are obviously the most famous ones ever in history. In the past one month, I’ve spent a lot of time reading works of theirs, including Principia Mathematica by

    Isaac Newton, General Theory of Relativity by Albert Einstein, A

    Brief History of Time by Stephen Hawking and An Old

    Man’s Toy: Gravity at Work and Play in Einstein’s Universe by an

    unknown Chinese author just to understand Einstein better.Here is my understanding of these three great men who “changed”

    our space.

    As a matter of fact, Newton and Einstein did the most important things to the world, and what makes Stephen Hawking special is his work A Brief History of Time which helps widespread the

    relativity theory of Einstein as well as his developing the black hole theory. So I will just devote most of my pages to Newton and Einstein.

    Newton's most important contribution to science is his mathematical definition of how motion changes with time. He showed that the force causing apples to fall is the same force that drives planetary motions and produces tides. However, Newton was puzzled by the fact that gravity seemed to operate instantaneously at a distance. He admitted he could only describe

    it without understanding how it worked. Not until Einstein's general theory of relativity was gravity changed from a "force" to the movement of matter along the shortest space in a curved spacetime. The Sun bends spacetime, and spacetime tells planets how to move. For Newton, both space and time were absolute. Space was a fixed, infinite, unmoving metric against which absolute motions could be measured. Newton also believed the universe was pervaded by a single absolute time that could be symbolized by an imaginary clock off somewhere in space. Einstein changed all this with his relativity theories, and once wrote, "Newton, forgive me."

    Einstein's first major contribution to the study of time occurred when he revolutionized physics with his "special theory of relativity" by showing how time changes with motion. Today, scientists do not see problems of time or motion as "absolute" with a single correct answer. Because time is relative to the speed one is traveling at, there can never be a clock at the center of the universe to which everyone can set their watches. Your entire life is the blink of an eye to an alien traveling close to the speed of light. Today, Newtonian mechanics have become a special case within Einstein's theory of relativity. Einstein's relativity will eventually become a subset of a new science more comprehensive

    in its description of the fabric of our universe. (The word "relativity" derives from the fact that the appearance of the world depends on our state of motion; it is "relative.")In terms of the forming of black hole, Einstein’s Gravity Theory is much different from Newton’s. To understand this better, we need to discover another great discovery of Einstein-----mass and energy is to some extent the same thing (you know the

    2known equation E=mc). But in Newton’s physics, mass is mass, energy is energy. The moving motion has a corresponding energy ----kinetic

    energy which is2?????

    have energy.

    mv , but on the contrary the body at rest doesn’t

    ?

    Energy and mass can both create gravitational field which

    emphasizes the difference between the two theories. In Newton’s theory, an object which has a mass can create gravitational field around it and that’s all.

    Einstein’ theory is much more complicated that the

    gravitational

    field also has energy and it creates an additional one. In other words, the star creates the gravitational field and the gravitational field creates an additional gravitational field and again the additional gravitational field creates an additional gravitational field until infinity. It’s a gravitational imitation using compound interest to make more money.

    Fields are added by fields, making the mathematical calculation of Einstein’s theory much more complex than Newton’s, the same as that calculating the compound interests is more complex than the simple interest.

    But in the normal state, the additional gravitational field is too

    small to be taken into consideration. But near a black hole, adding all the additional gravitational fields can make the space and time extremely curved, generally speaking, until the texture of space and time is torn up and the collapsed star is pressed until it no longer exists as a “star”.

    If you observe Mercury to a very accurate way, you will find out a slight difference between the exact movement and the forecasted one by Newton’s theory. Einstein’s general relativity’s prediction matches what is observed but Newton’s theory can’t do this. However, when we deal with the normal situation, the difference between Newton and Einstein is too small to consider, so for a functional purpose, we still use Newton’s theory. (PS: Newton’s theory has a huge advantage that the calculation is a lot easier than Einstein’s)

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