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World outlook

2022-06-27 11:33:59Reading notes

World view ,“ If you read books you can understand every day , You only know the known world view ”. The world is not changing too fast , Maybe your world view hasn't been refreshed yet . Growth , Just use “ World view ” Upgrade cognition . This is a popular liberal arts reading book in American universities , A necessary introduction to the philosophy of science and the history of science . This book discusses western science for twothousand years , Explore the origin of science and the nature of thinking . This is what every modern person needs to read 、 About the history and philosophy of science , Help readers build a correct world view .

 World view

World view value

“ If you read books you can understand every day , You only know the known world view ”. The world is not changing too fast , Maybe your world view hasn't been refreshed yet . Growth , Just use “ World view ” Upgrade cognition . This is a popular liberal arts reading book in American universities , A necessary introduction to the philosophy of science and the history of science .

This book discusses western science for twothousand years , Explore the origin of science and the nature of thinking . This is what every modern person needs to read 、 About the history and philosophy of science , Help readers build a correct world view .

World view Reading harvest

  • Build a new cognitive system , Refresh the existing world outlook

  • Establish a view of the world 、 Knowledge learning is “ The underlying logic ”

  • Master the basic context of philosophy of science and history of science

World view Selected golden sentences

1. Interestingly , The definitions of fact and truth often depend on each other .

2. For a scientific theory , No matter how many evidences can prove its correctness , There's always the possibility that this theory is wrong .

3. If we trust each other , Then what we do will be completely different from when we don't trust each other .

4. Some of our views may affect some aspects of reality in some boring way .

 World view

World view Author's brief introduction

[ beautiful ] Richard · Dwight

Professor of Fairfield University , In addition to studying the history and philosophy of Science , His field of study also includes philosophical thinking 、 Mathematics and philosophical logic . He made use of his rich experience in classroom teaching to 《 World view 》 The manuscript of a book is polished repeatedly , It is supplemented by rich charts . meanwhile , The author has the unique ability to decompose complex technical concepts into languages that readers can understand , It's mind opening to read .

fine Hua Explain read

The following is 《 World view 》 An interpretation of the essence of a Book , For the majority of book friends to learn reference , Welcome to share , It cannot be used for commercial purposes without permission .

World view Text

One 、 Understanding the world view

What is called “ World view ”?“ World view ” This concept is often used as “ Three views ” One appears , But few people can say what it is . In this book , The author gives his definition :“ World view ” It refers to a system of views , Different points of view are like pieces of jigsaw puzzle , Interconnected . in other words , Worldview is not just about separation 、 Independent 、 A collection of unrelated ideas , But a different point of view intertwined 、 Relate to each other 、 An interconnected system .

For example, Aristotle's world view , It was... BC 300 Year to ad 1600 The dominant viewpoint system in , It is not Aristotle's personal view , It is only based largely on Aristotle's point of view .

 World view

The puzzle of Aristotle's world view

So what is Aristotle's point of view ? such as , He thinks the earth is at the center of the universe , It's static ; The moon 、 Other planets and the Sun move around the earth , About every 24 Run an hour ; The area between the earth and the moon is called the sublunar region , It consists of four elements , Namely soil 、 water 、 Gas and fire ; The area outside the moon is called the upper part of the moon , The material in this area consists of a fifth element “ The etheric ” constitute ,“ The etheric ” There is a natural tendency to move in circles ……

Aristotle's worldview rules the western world 1900 Years or so , Until it was overthrown and replaced by Newton's world view . Newton's worldview holds that , The earth revolves around its axis , About every 24 One revolution per hour ; The earth and planets orbit the sun in an elliptical orbit ; There are slightly more kinds of basic elements in the universe than 100 Kind of ; A moving object tends to remain in motion , The same rule applies to objects such as planets and stars ……

Most of the ideas in Newton's worldview are still applicable today , But the rapid development of modern relativity and quantum mechanics , Challenging Newton's world view . The world outlook has been in the process of continuous iteration and updating , The existing world outlook may also become a thing of the past as Aristotle's world outlook is overturned . We live in an interesting era .

 World view

Two 、 The basic proposition of world outlook

1. truth

Everyone may believe in some so-called truth , But few people can really understand what truth is . About the definition of truth , In fact, there are two more universal versions .

(1) The correspondence of truth

According to the theory of truth correspondence , The factor that determines the truth of an idea is that the idea is consistent with reality ; The factor that determines an opinion to be false is that it does not conform to reality . The reality here refers to “ Really? ” reality , This reality is completely objective , Independent of human opinion .

for instance , If “ The earth revolves around the sun ” This view is true , Then the factor that determines its truth must be that this view is consistent with the real situation of things , That is, the earth is really moving around the sun .( But until now , We have no direct evidence that the earth moves around the sun .)

that , How to judge that what we see must be objective ? The author raises a puzzle , When everyone looks at the world , In fact, they can't jump out of their own consciousness . in other words , There is no way for us to evaluate whether the representation provided by the senses is accurate , Or to put it another way , We have no way to determine what the real reality is like .

 World view

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(2) The integration of truth

According to the theory of truth Integration , What determines the truth of a point of view is that it is consistent with other points of view , Or close together . So what is said above “ Other ideas ” What are their views ? Depending on the source of the point of view , The theory of truth integration can be divided into at least three types : On the integration of individualism 、 Group coherence theory and science based coherence theory .

a. On the integration of individualism

For individuals , If one point of view can be consistent with other points of view , So this view is true for this person . such as , If Steve thinks “ The moon is inhabited ” This view is true , So in the system of individualism integration theory , No one could convince Steve that the moon was uninhabited . All in all , The integration of individualism is actually a kind of “ Anything is possible ” Relativism .

b. Group integration theory

According to the theory of group integration , If a point of view can be put together with the overall point of view of a group , Then this view is true . But the problem with this view is , The view held by the group may also be wrong , And there is no way to know who is part of the group .

c. The integration theory based on science

If a view related to science can be combined with the views of some scientists , Then this view is true . The integration theory based on science is also a group integration theory .

therefore , The theory of integration of truth may be greatly different because of different kinds of existence . In the last few thousand years , People have been discussing the truth , But no consensus has been reached .

 World view

2. Empirical facts and philosophies / Conceptual facts

(1) Experience facts

Facts based on observation , It's often called empirical fact . If there is a pencil on the desk , that “ There is a pencil in front of you ” Is a clear empirical fact .

 

(2) Philosophic / Conceptual facts

It depends on people's philosophical understanding of the world they live in / Conceptual judgment , This fact is called philosophical / Conceptual facts . If you see the pencil mentioned above being put into a drawer , You will think “ There is a pencil in the drawer ”, Although you don't see the pencil directly in the drawer . This judgment comes from the way we look at the world .

 

Empirical facts and philosophies / Conceptual facts are often intertwined , It is difficult for us to categorize certain views simply . for instance , In Aristotle's time , People draw some empirical facts from observation , For example, some stars seem to move at a uniform speed along a perfect circle , On the basis of these empirical facts , People come to the corresponding philosophical / Conceptual facts —— The star moves at a constant speed in a perfect circular orbit .

 

Although now I see “ A perfectly circular orbit ” and “ Move at a constant speed ” theory , We will find it incredible , But this was the obvious conclusion at that time . therefore , We know “ Obvious ” It may be a thinking trap . meanwhile , Don't mistakenly think that you are living in this era of modern science , We have escaped the belief in philosophy / The pitfall of conceptual facts .

 World view

3. Confirmatory reasoning and non confirmatory reasoning

Around the 100 Years ago , Einstein put forward the theory of relativity , This theory caused great controversy at that time . Einstein predicted in his theory that large objects , Like the sun , Its gravitational effect will bend the light of the star . later , stay 1919 year 5 During the total solar eclipse of September , The researchers observed that the light did bend as Einstein predicted . This observation became an important evidence to support Einstein's theory of relativity , This is actually a kind of confirmatory reasoning .

The author gives a diagram to show the process of confirmatory reasoning :

If T, Then come to O

O(O That's right. )

therefore T( It is very likely to be correct )

Confirmatory reasoning is a kind of inductive reasoning . The characteristic of inductive reasoning is , In an inductive reasoning process , Even if all the prerequisites are true , The conclusion may also be wrong . therefore , For a scientific theory , No matter how many evidences can prove its correctness , The possibility that this theory is wrong always exists .

On the inference of unconfirmed , The author also gives a schematic diagram :

If T, Then come to O

O It's not true

therefore T It's not true

Unconfirmed reasoning is a deductive reasoning . The characteristic of deductive reasoning is , In a deductive reasoning process , The real premise guarantees the real conclusion . such as , Socrates has a famous syllogism : People die , Socrates is a man , So sugra will die , This is a correct reasoning . Similarly, , According to legend, Plato once said , A hairless two legged animal is a human . His students heard it , Just catch a chicken , Pull out the hair , According to Plato's definition , Then the plucked chicken is also human . obviously , This reasoning is wrong , Because the big premise is wrong .

 World view

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however , Usually, unsubstantiated reasoning involves a large number of auxiliary assumptions , therefore , The evidence derived from unconfirmed reasoning can only show that either the theory used is incorrect , Either one or several auxiliary assumptions are incorrect .

On the inference of unconfirmed , The author gives a more accurate schematic diagram :

If T, And A₁,A₂,A₃…,An, that O

O It's not true

therefore T It's not true , perhaps A₁ It's not true , perhaps A₂ It's not true , perhaps A₃ It's not true … perhaps An It's not true .

such as , The researchers heated the alcohol in a beaker , If the researcher observes that the sample does not boil when it reaches the boiling point of alcohol , So we can come to a conclusion , Either the sample is not ethanol , Or the thermometer is broken , Or the sample is contaminated , Or the air pressure in the laboratory is abnormal .

4. Falsificationism and falsifiability

Carl · Popper is the most famous supporter of falsificationism , He believes that falsification is a key element of science , It is also the key premise to distinguish scientific theory from non scientific theory . Pope thinks , The emphasis of science should be on trying to refute the theory , Instead of confirming the theory . As discussed in the above confirmatory reasoning , For any scientific theory , No matter how much evidence there is to prove its correctness , This theory has the possibility of being wrong .

In a sense , For Pope , The greater the risk a theory takes , The more scientific it is , Such as Einstein's theory of relativity .

 

that , How do we know whether a theory is falsifiable ? The author thinks that , Falsifiability is actually a very subtle and complex proposition , Because we are not sure what kind of evidence is meaningful evidence . When you try to prove whether a theory is falsifiable , Inevitably, you will join your own viewpoint system , The final result may be that neither of these two opinion systems can convince the other .

 

therefore , The author thinks that , Falsifiability is the attitude towards a certain theory , Not a feature of the theory itself , It is this attitude that determines whether the theory can be falsified or not .

 World view

5. Instrumentalism and realism

For instrumentalists , A proper theory can give predictions and explanations , As for whether this theory reflects or simulates the real world , Not an important consideration . And for realists , the facts are just the opposite , A reasonable theory must not only give predictions and explanations , And it should reflect the real situation of real things .

 

Ptolemy used the cycloid circle to study the motion of Mars , Here's the picture . In the earth centered universe , Mars surrounds the point A The circular orbit in motion is called the epicyclic circle .

 

The motion of Mars in the Ptolemy system

For instrumentalists , It doesn't matter whether the circle of turnover really exists , What is important is that the theory can predict and interpret relevant data ; And for realists , If the circle of turnover does not really exist , Then Ptolemy's theory cannot be accepted .

 

Interestingly , Treat gravity , Newton himself, who put forward the concept, held an instrumentalist attitude . in other words , He can use his own equations to make relevant predictions , But whether gravity is a “ real ” Force , He himself is silent .

3、 ... and 、 The transformation from Aristotle's worldview to Newton's worldview

1. Aristotle's world view

In the western world , Around BC 300 Year to ad 1600 Year , Aristotle's world view is the dominant world view .

 

Here are some of the main points of Aristotle's world view :

(1)“ geocentrism ”: The earth is at the center of the universe , It's spherical .

(2) The relationship between the earth and the moon : The moon is closest to the earth , The area between the moon and the earth is the sublunar area , The area above the moon is the upper lunar area , Made up of the elemental ether .

(3) The order of the stars and the sun : The first is mercury , And then Venus , Next comes the sun 、 Mars 、 Jupiter 、 Saturn and the so-called stellar sphere .

(4) The universe : The edge of the universe is the sphere where the star is located , All stars are equidistant from the earth , And they are embedded in a sphere . The sphere rotates about its axis , Turn it around for about 24 Hours .

(5) Teleology and essentialism : The universe has a purpose , And there is an essence . The natural goal of every basic element in the universe is to reach its natural position in the universe , Natural objects are considered to have essential properties , And because of these essential attributes , Objects have their behavior patterns . For example, the natural trend of earth elements is to be located in the center of the universe , That is, geocentric theory .

 

Near 2000 In a matter of years , Aristotle's worldview is accepted as a universal view , Although with the development of the times , The theory is constantly revised , But its theoretical basis is still a earth centered 、 There is an essential existence 、 A purposeful universe .

 World view

2. Astronomical data : Experience facts

(1) Stellar motion

Bright spots known as stars move in a predictable pattern , This movement pattern has been discovered long before the beginning of recorded human history . The motion of stars seems to follow a regular pattern , nearly 24 Repeat once every hour . The sun rises in the East and sets in the West relative to the earth , This determines the diurnal variation of the earth ; meanwhile , Its position on the edge of the earth changes every season , This determines the earth's vernal equinox 、 the summer solstice 、 Autumnal equinox and winter solstice .

 

(2) The motion of the moon

The more obvious lunar movements include , The moon is about every 29 More than once a day ; Relative stars , It will drift East , But it shifts faster than the sun .

 

(3) The motion of the planets

On any night , We call it a bright spot of the planet , It doesn't look significantly different from a bright spot we call a star , The way it operates in the air is similar . therefore , It is difficult to distinguish between stars and planets .

 

However, our forefathers have long discovered that there are 5 The three highlights are different from thousands of others . This difference is mainly based on this 5 A bright sports mode , But it's not their movement on one night , But a pattern formed through many nights .

 

By the way , We usually think that there is 9 planet , But until 18 century , All we can see is gold 、 wood 、 water 、 fire 、 Tu Tu 5 planet .

 

for instance , If you spend hours looking at Jupiter , You will find that it moves with the stars , And it usually doesn't look any different from a star . However, if you look closely at Jupiter for days or weeks , You'll notice , Similar to the moon and the sun , The relative positions of Jupiter and its stars are constantly shifting .

 

It is also worth mentioning that , Unlike stars , The brightness of the planets varies greatly . When Venus is visible to the naked eye , It always looks quite bright , But sometimes it will be brighter than other times , At its brightest , Venus looks like a landing light on a landing plane .

 World view

5 Every planet visible to the naked eye will often have a significant change in brightness , The actual situation is more complicated than this . such as , Planets do a kind of “ Offset movement in the opposite direction ”, Also called “ Retrograde motion ”. All planets have retrograde motion , Although retrograde intervals are not exactly the same . Jupiter and Saturn go retrograde about once a year , Mars goes retrograde about once every two years , Venus comes about once a year and a half , Mercury goes retrograde about three times a year .

 

I believe many people may be interested in the night sky , Especially children . So how to observe Venus with the naked eye ? The author mentions in the book that , According to the change of the position relationship between Venus and the sun , You can wait until the sun is about to rise , Or I saw it within a few hours after it fell .

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3. Astronomical data : Philosophic / Conceptual facts

Under Aristotle's worldview system ,“ The sky is a perfect place ” Point of view , It provides a way to explain how celestial bodies keep moving . Inseparable from this view is ,“ The celestial body must be moving at a constant speed along a perfectly circular orbit ”. in the course of time , It seems to be common sense that the planets move at a constant speed in a perfect circular orbit . Now we look back and find , The fact of a perfect circle and the fact of uniform motion are not the same at all , But a philosophical / Conceptual facts , And it's wrong .

 

4. Ptolemaic system

Ptolemy in A.D 150 In published 《 The most important thing 》, In his book, he put forward a whole set of sports system . The Ptolemaic system clearly respects the fact of the perfect circle , Because the methods used by Ptolemy are all based on “ The motion of celestial bodies is only in a perfect circular orbit ” On the basis of .

Although Ptolemy system is not perfect , And many mistakes , But it is worth emphasizing that , Before or after Ptolemy 1400 During the year , There are no other theories about the structure of the universe , It is close to Ptolemaic system in explanation and prediction .

 

In Ptolemy's system , Mars moves along a point , That is, the point in the figure below A. The circle formed by the trajectory of Mars , That is to say, with a dot A A small circle at the center of a circle , It is called a revolving circle .

 World view

Ptolemy system's study of Mars

The center of the epicyclic circle , That is to say A, More along a radius 、 With a little B Running for a centered circle . A circle with a larger radius like this is called an even wheel or an eccentric circle .

 

In the diagram above , It is not the earth at the center , But point B, But notice , The earth is indeed the center of the Ptolemaic system . When B When it coincides with the center of the earth , Well, this is based on B A circle with a larger radius of the center will be called a uniform wheel . In another case , If you order B Not at the center of the system , Then this larger circle will be called an eccentric circle .

 

in short , The uniform wheel and eccentric circle have the same thing in that they are circles with larger radius formed by the revolving circle running track . It can be considered that an eccentric circle is a uniform wheel whose center is offset . In this circle , A point can be found by calculation , If the center of the circular circle of Mars moves at a uniform speed relative to this point , Then this point is called an equidistant point .

 

Turnover circle - The wheel balancing system is very flexible , Because you only need to change the size of each component 、 Speed and direction of motion , Can produce a lot of different movements . With a high degree of flexibility , So the turnover circle - The wheel balancing system is very useful .

 

5. Copernicus system

Ptolemy's theory probably continued 1400 many years , Next on the stage is Nicholas · Copernicus .

 World view

Copernicus in 16 At the beginning of the th century, it was proposed that the sun is the center of the universe , The Copernican system is similar to the Ptolemaic system in many ways , But the positions of the earth and the sun are reversed . Copernicus believed that all stars were equidistant from the center of the universe , They are also embedded in the so-called stellar sphere .

As in Ptolemy , This stellar sphere is the farthest boundary of the universe . Copernicus' universe is larger than Ptolemy's universe . The Copernican system also uses the circle of gyration 、 Equalizing wheel and eccentric circle , And again , Copernicus also respected the fact that the orbit was perfect and the motion was uniform .

 

Copernicus bypassed the concept of equidistant points in the Ptolemaic system , The fact of uniform motion is directly and explicitly respected , And for retrograde motion 、 The correlation between the different brightness of multiple planets and the time point of their retrograde motion , And Venus 、 The fact that Mercury always appears not far from the sun , Made a more direct and clear explanation .

 

Why did Copernicus put forward heliocentric theory ? It is said that , It is related to a school of philosophy called Neo Platonism . Neo Platonism holds that , The sun is the best , The sun became “ lord ” The representative of the . that , For Copernicus, who believed in Neo Platonism , The sun is supposed to be at the center of the universe .

 World view

6. Tycho system

Valley of the valley · Brahe is 16 A respected astronomer in the second half of the th century , His main contribution was to develop what is now called the Tycho system , And has given very accurate empirical observations over the decades .

 

Tycho developed a system based on his own ability , It includes the advantages of most Copernican systems , Keep it again “ The earth is the center of the universe ” Point of view . According to the Tycho system , The earth is the center of the universe , The stellar sphere is also defined as the boundary of the universe . The moon and the sun go round the earth , But the planets revolve around the sun .

 

7. Kepler system

After Tycho died , Kepler obtained some key data accumulated by Tycho , On this basis , He studied with extraordinary efforts , Finally made two key innovations —— Elliptical orbit and variable speed motion .

 

According to the Kepler system , The planets orbit the sun in an elliptical orbit , The sun occupies one of the two focal points of an elliptical orbit , This theory is often called Kepler's first law of planetary motion .

 

Kepler's other major innovation is to allow planets to change speed as they orbit around the sun . More specifically , If you draw a straight line from the planet , Connected with the sun , This line sweeps the same area in the same time . This description of the speed of planetary motion is called Kepler's second law of motion .

 

finally , stay 17 Mid Century , About uniform velocity 、 The philosophical nature of motion along a perfect circle / Conceptual “ The facts ” No longer considered a fact .

8. Galileo system

In the process of changing from geocentric view to heliocentric view , Another person who played a central role was Galileo .

 World view

Galileo was one of the first people to use a telescope for astronomical observation , By using a telescope , He found interesting new data , These data have had a great impact on the debate between geocentric and heliocentric supporters . Here are some of Galileo's discoveries :

 

(1) Mountains on the moon

The features of the lunar surface observed by Galileo include mountains 、 Plains and what we now call moon pits . This is in line with Aristotle's world view “ All objects in the sky are made of ether ” The views of . But this is not enough to shake the status of Aristotle's world view , After all , The idea of the moon is not at the heart of Aristotle's worldview .

 

(2) Sunspots

Galileo was also one of the first people to observe sunspots with a telescope . Use the observations , Galileo is believed , Sunspots must be areas on the surface of the sun itself , Not any other image . therefore , The upper lunar region is certainly not as Aristotle's worldview suggests , Is a perfect area . therefore , Aristotle's worldview has one more flaw .

 

(3) Saturn's rings or ears

Galileo was the first to observe that Saturn sometimes has a bulge on its edge , This protruding edge looks like a handle or ear . This data once again challenges Aristotle's worldview , Because by the so-called “ The etheric ” A planet is not necessarily a sphere , The moon and the sun are not .

 

(4) The moons of Jupiter

Galileo observed four small bright spots orbiting around Jupiter , He correctly concluded that the four small bright spots were satellites orbiting Jupiter . According to Aristotle's worldview , Especially in the Ptolemaic system , The earth is the only center of all circular motion in the universe . obviously , The discovery of Jupiter's moons , Once again, it cast a shadow on Aristotle's world view .

 World view

(5) Venus phase

The so-called Venus phase , It means that Venus will not only experience periodic phase changes , And its size will also change according to the phase . This is what Galileo observed through a telescope .

 

And Galileo also discovered , Except for stars visible to the naked eye , There are countless other stars . It means at least , The universe is probably much larger than previously thought , It may even be infinite , This includes an infinite number of stars .

 

1632 year , Galileo published 《 Dialogue on the two world systems of Ptolemy and Copernicus 》 A Book , This book is rich in content , Arguments for and against geocentric system and heliocentric system are discussed respectively . The book was not accepted by the church , Because at that time , Only discussing heliocentric system is not forbidden by church , What is forbidden is that it is a realistic practice to support this view . Galileo just violated the taboo of the Church .

 

Finally Galileo was found to be suspected of heresy , Be sentenced to life imprisonment , At the same time, they were asked to officially announce “ Heliocentric theory ” My view is false . Last , Galileo spent the rest of his life at home , On 1642 Death in .

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9. Newton's worldview

Like some kind of “ rebirth ”, In the first year after Galileo's death , Newton was born .17 The 21st century is an era full of changes , New science began to emerge and developed rapidly , This is the result of the joint efforts of many researchers . But the master was Newton , He was in 1687 In published 《 The mathematical principles of natural philosophy 》, abbreviation 《 principle 》.《 principle 》 It shows a new kind of Physics , Created a new view puzzle , A puzzle of ideas that replaces Aristotle's worldview —— Newton's worldview .

 World view

In Newton's worldview , The universe is thought to be vast , It may even be infinite , The sun is just the center of the solar system , The planets move around the sun ; The reason for the formation of object operation mode is no longer its internal essence , contrary , An object forms its mode of operation under the influence of an external force ; The universe keeps moving day by day , It's like a clock ticking away every day .

 

(1) Newton's three laws

Newton's first law , That is what we often call the law of inertia : Any object is free from any external force , Always maintain a uniform linear motion or a static state , Until an external force forces it to change this state .

 

Newton's second law : The change in motion of a body is proportional to the force it is subjected to , And it is in line with the direction of the applied force . This law is usually summed up as F=ma, That is, the force acting on the object is equal to the mass times the acceleration .

 

Newton's third law : For any force , There is always an opposite direction 、 Reactions of equal magnitude .

 

(2) The law of gravity

Gravitation is usually expressed as the mutual attraction between any two objects , The gravitational action between two objects is directly proportional to the mass of the object . The greater the mass of the object , The stronger the gravitational force . Newton is still 《 principle 》 Volume III presents , Gravity is universal in all objects . however , Newton usually claimed that he regarded gravity with an instrumentalist attitude .

 

Like Aristotle's world view , Newton's worldview is not a series of static views . stay 17 For centuries after the th century , Newton's world view has been developed and revised , But nonetheless , The core elements of this worldview remain unchanged .

 

In the field of Chemistry , Anthony · Lavoisier used quantitative research methods to carry out chemical research , Soon this research method became the mainstream of the academic circles at that time . Use the same method , John · Dalton constructed his atomic theory , This is a theory basically within Newton's scientific system . Throughout 19 Century and 20 At the beginning of the century , By applying Newton's method , Remarkable achievements have been made in chemical research .

 

In Biology , It has been found that some phenomena related to nerves are actually electrical phenomena , The physics that causes this phenomenon 、 Chemical processes and physics beyond biology 、 Chemical processes are of the same kind . This field of biology can be compared with Newton's world view to physics 、 The mechanistic aspects of chemical processes are pieced together .

 

similarly , Newton's basic mathematical quantitative method has also been used in the study of electromagnetism , Both Faraday's and Maxwell's research results benefit from Newton's quantitative method of basic mathematics to a certain extent .

 

These are just three of the many fields of science under Newton's system , Impressive achievements and discoveries have been made in many other fields of Science , The influence of Newton's worldview is universal and profound .

 World view

(3) A few small dark clouds

Sir Kelvin, a famous British physicist, was in 1900 A conversation was published in , He pointed out that , In the clear sky of modern science , Now there are only a few left “ Little dark cloud ” 了 . Two of them are the most important , Michael Jackson - Morey experiment and blackbody radiation .

 

① Michelson - Morey experiment

Michelson and Murray emit two rays of light from a fixed point , The included angle when sending is a right angle , The two rays of light are reflected back by two mirrors that are at the same distance from the light source . If the mechanistic view of light propagation in Newton's system is correct , That is, light travels through the medium ether , Then the light source and the mirror should move in the ether .

Although relative to the light source , Two rays of light travel at equal distances , But because the light source and the mirror move in the ether at the same time , So for the ether , The distance between two rays of light is not equal , So we expect to see a slight time difference between the two lights returning to the light source . However, contrary to expectations , The two lights always return to the light source at the same point in time .

 

Because Newton's scientific system was very successful , Therefore, scientists believe that if the viewpoint of Newton's scientific system is abandoned because of this experimental result , Would be very unwise , So I regard it as an insignificant little dark cloud .

 

② Blackbody radiation

Blackbody refers to an idealized object , It can absorb all the electromagnetic radiation pointing to it . for instance , Light is a form of electromagnetic radiation , therefore , If we cast light on a blackbody , Blackbody will absorb all the light , Thus showing the nature of darkness , That's why it's called bold .

 

According to Newton's scientific system , A heated blackbody , It is expected that external radiation will be conducted in a certain mode . However, actually observed radiation patterns , It is significantly different from the radiation pattern predicted by Newton's scientific system .

 

In short , When only long wavelength radiation is observed , The observed radiation pattern is very close to the predicted pattern . But when it comes to shortwave , The observed radiation patterns are quite different from the predicted patterns . This problem is sometimes called “ UV disaster ”.

 

With Michelson - Just like the Morey experiment , The problem of blackbody radiation turned out to be more than a small dark cloud . Until the advent of quantum theory , The problem of blackbody radiation was successfully explained .

 World view

Four 、 Relativity and quantum theory

1. Special relativity and general relativity

In addition to the above small dark clouds , In most people's world view , Space and time are absolute . All of this , There are different explanations in the theory of relativity . Albert · Einstein in 1905 In, he published the special theory of relativity , On 1916 General relativity was published in . Here are some common ideas of relativity :

 

Special relativity is based on the principle of constant speed of light and the principle of relativity , For a moving object , There will be some surprising changes in space and time , Such as the expansion of time 、 Length shrinkage 、 Relativity of simultaneity, etc .

 

General relativity is based on the general covariance principle and the equivalence principle . According to general relativity , The existence of massive objects leads to the curvature of space-time . Objects that are not subjected to any force will also move along the shortest path, and so on . This part is detailed in 《 From Einstein 》.

 World view

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2. Quantum Theory

Quantum theory is actually a kind of “ wave ” mathematics , Should and “ The particle ” Mathematics is different . One involves discrete objects ( The particle ) Used in , The other is used in the case of waves . for instance , If you throw a bowling ball , Bowling ball is an object that will be affected by multi gravity , The mathematics in this case is particle mathematics . But water waves 、 light wave 、 Sound waves and other situations involving waves , We need quantum mathematics .

 

that , Why is quantum theory so unusual ? It is worth mentioning that , What quantum theory mathematics gives is usually a probabilistic prediction , Not certain predictions . for instance , If we use quantum theory to predict the position of an electron , Mathematical calculations will tell us the possibility of detecting this electron at different locations . by comparison , If it's a bowling ball falling from the roof , Mathematical calculations will give us a definite prediction . This is exactly the difference between quantum theoretical mathematics and other theories .

 

To better understand quantum theory , We can learn about Schrodinger's cat , Schrodinger's cat is a thought experiment about quantum theory . Suppose there is a cat in a sealed box , There is also a weak source of radiation .

 World view

say concretely , This radioactive source in an hour , The probability of releasing a radioactive particle is 50%. If the radioactive source releases a radioactive particle , This particle will trigger a detector , The detector will open a small bottle of poison after triggering , This poison can poison the cat in the box .

Quantum mechanics tells us , There is an intermediate state , A cat is neither dead nor alive , Until you look and see what happens . Unless observations are made , Otherwise, nothing is certain , But this makes the micro uncertainty principle become the macro uncertainty principle , Objective laws are not transferred by human will , The cat lives and Dies against logical thinking .

 

On the further interpretation of Schrodinger's cat , There are many views in the academic circles , But so far no consensus has been reached . The only consensus is , Mankind has just entered the gate of quantum theory .

World view Conclusion

Through the study of this book , We have a general understanding of what kind of world we live in . From Aristotle's world view to Newton's world view , And then to the development of relativity and quantum theory , Our world view is in the process of updating and iterating .

Past views , Not necessarily now , The present world outlook may also be subverted by future discoveries . But what we can be sure of is , We live in interesting times .

Such is the view of life , How magnificent , Please continue to be a thinking reed .

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