1. The concept of a scientific picture of the world
The very concept of “scientific picture of the world” appeared in natural science and philosophy at the end of the 19th century, however, a special, in-depth analysis of its content began to be carried out from the 60s of the 20th century. And, nevertheless, until now an unambiguous interpretation of this concept has not been achieved. The fact is that this concept itself is somewhat vague, it occupies an intermediate position between the philosophical and natural-science reflection of the trends in the development of scientific knowledge. So there are general scientific pictures of the world and pictures of the world from the point of view of individual sciences, for example, physical, biological ..., or from the point of view of any dominant methods, styles of thinking - probabilistic-statistical, evolutionary, systemic, informational-cybernetic, synergetic, etc. P. pictures of the world. At the same time, the following explanation of the concept of the scientific picture of the world can be given. (NKM).
The scientific picture of the world includes the most important achievements of science, creating a certain understanding of the world and the place of man in it. It does not include more specific information about the properties of various natural systems, about the details of the cognitive process itself. At the same time, NCM is not a collection of general knowledge, but is an integral system of ideas about the general properties, spheres, levels and patterns of nature, thus forming a person's worldview.
Unlike rigorous theories, NCM has the necessary visibility, is characterized by a combination of abstract theoretical knowledge and images created with the help of models.
Features of various pictures of the world are expressed in their inherent paradigms.
Paradigm (<греч. пример, образец) совокупность определенных стереотипов в понимании объективных процессов, а также способов их познания и интерпретации.
Thus, we can give the following definition of NCM.
NCM is a special form of systematization of knowledge, mainly their qualitative generalization, ideological synthesis of various scientific theories.
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2. Formation of a mechanical picture of the world (MCM)
In the history of science, scientific pictures of the world did not remain unchanged, but replaced each other, so we can talk about evolution scientific pictures of the world. The most obvious is the evolutionphysical pictures of the world: natural-philosophical until the 16th-17th centuries, mechanistic until the second half of the 19th century, thermodynamic (within the framework of mechanistic theory) in the 19th century, relativistic and quantum-mechanical in the 20th century. Figure 1 schematically shows the development and change of scientific pictures of the world in physics.
Fig.1. Physical pictures of the world
The physical picture of the world is created thanks to fundamental experimental measurements and observations, on which theories are based, explaining the facts and deepening the understanding of nature. Physics is an experimental science, therefore it cannot achieve absolute truths (as well as knowledge itself in general), since experiments in themselves are imperfect. This is due to the constant development of scientific ideas.
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3. Basic concepts and laws of MKM
The MKM was formed under the influence of materialistic ideas about matter and the forms of its existence. The fundamental ideas of this picture of the World are classical atomism, dating back to Democritus and the so-called. mechanism . The very formation of a mechanical picture is rightly associated with the name of Galileo Galilei, who first applied the experimental method to the study of nature, along with measurements of the quantities under study and subsequent mathematical processing of the results. This method was fundamentally different from the previously existing natural-philosophical method, in which, to explain the phenomena of nature, a priori (<лат. a priori lit. to experience), i.e. not related to experience and observation, speculative schemes, to explain incomprehensible phenomena, additional entities were introduced, for example, the mythical “liquid” caloric, which determined the heating of the body, or phlogiston substance that ensures the combustibility of a substance (the more phlogiston in a substance, the better it burns).
The laws of planetary motion discovered by Johannes Kepler, in turn, testified that there is no fundamental difference between the movements of earthly and celestial bodies (as Aristotle believed), since they all obey certain natural laws.
The core of MCM is Newtonian mechanics(classical mechanics).
The formation of classical mechanics and the mechanical picture of the world based on it took place in 2 directions (see Fig. 2):
1) generalizing the results obtained earlier and, above all, the laws of free fall of bodies discovered by Galileo, as well as the laws of planetary motion formulated by Kepler;
2) creating methods for the quantitative analysis of mechanical movement in general.
Rice. 2
In the first half of the 19th century Along with theoretical mechanics, applied (technical) mechanics also stands out, having achieved great success in solving applied problems. All this led to the idea of the omnipotence of mechanics and to the desire to create a theory of heat and electricity also on the basis of mechanical concepts. This idea was most clearly expressed in 1847 by the physicist Hermann Helmholtz in his report “On the Conservation of Force”:“The ultimate task of the physical sciences is to reduce the phenomena of nature to constant attractive and repulsive forces, the magnitude of which depends on distance”
There are quite a lot of concepts in any physical theory, but among them there are the main ones, in which the specificity of this theory, its basis, worldview essence is manifested. Such concepts include the so-called.fundamentalconcepts, namely:
matter,
traffic,
space,
time,
interaction.
Each of these concepts cannot exist without the other four. Together they reflect the unity of the World. How were these fundamental concepts revealed within the framework of the MCM?
MATTER. Matter, according to MKM is a substance consisting of the smallest, further indivisible, absolutely solid moving particles atoms, i.e. discrete ( discrete “discontinuous”), or, in other words, corpuscular ideas about matter. That is why the most important concepts in mechanics were the concepts of a material point and an absolutely rigid body (Material pointa body whose dimensions can be neglected under the conditions of this problem,absolutely rigid bodya system of material points, the distance between which always remains unchanged).
SPACE . Recall that Aristotle denied the existence of empty space, linking space, time and motion. Atomists 18-19 centuries on the contrary, they recognized atoms and empty space in which atoms move. Newton, however, considered two types of space:
relative , which people get to know by measuring the spatial relationship between bodies;
absolute , which by its very essence is irrespective of anything external and remains always the same and motionless; those. absolute space isempty container of bodies, it is not connected with time, and its properties do not depend on the presence or absence of material objects in it. Space in Newtonian mechanics is
Subsequently, A. Einstein, analyzing the concepts of absolute space and absolute time, wrote: “If matter disappeared, then only space and time would remain (a kind of stage on which physical phenomena are played out).” In this case, space and time do not contain any special “marks” from which one could count and answer the questions “Where?” and when?" Therefore, to study material objects in them, it is necessary to introduce a reference system (coordinate system and clock). The frame of reference rigidly connected with absolute space is called inertial.
three-dimensional (the position of any point can be described by three coordinates),
continuous,
endless
homogeneous (the properties of space are the same at any point),
isotropic (properties of space do not depend on direction).
Spatial relations in MKM are described by Euclid's geometry.
TIME . Newton considered two types of time, similar to space: relative and absolute. People learn relative time in the process of measurements, and absolute (true, mathematical time) in itself and in its essence, without any relation to anything external, flows evenly and is otherwise called duration. Thus, Newton's time, similarly to space, is an empty receptacle of events that does not depend on anything. Time flows in one direction from the past to the future.
TRAFFIC . The MKM recognized only mechanical movement, i.e. a change in the position of the body in space over time. It was believed that any complex movement can be represented as the sum of spatial displacements (superposition principle). The motion of any body was explained on the basis of Newton's three laws, while using such important concepts as strength and mass . In MCM, force is understood as the cause of a change in mechanical motion and the cause of deformation. In addition, it was noticed that it is convenient to compare the forces by the accelerations of the same body caused by them ( m = const ). Indeed, it follows from the second law that F 1 / F 2 \u003d a1 / a2, while the value m \u003d F / a for a given body was a constant value and characterized inertia body. Thus, the quantitative measure of the inertia of a body is its inertial mass.
INTERACTION. Here we should return to our time and see how the issue of interactions (the root cause, the nature of forces) is being resolved within the framework of the modern scientific picture of the World. Modern physics reduces all the variety of interactions to 4th fundamental interactions: strong, weak, electromagnetic and gravitational. In the future, they will be considered in more detail. Here we will stop on gravitational.
Gravitational interaction means the presence of attractive forces between any bodies. The magnitude of these forces can be determined from the law of universal gravitation. If the mass of one of the bodies (standard) and the gravitational force are known, the mass of the second body can also be determined. The mass found from the law of universal gravitation is called gravity . Earlier it was already said about the equality of these masses, therefore the mass is both a measure of inertia and a measure of gravitation. Gravitational forces are universal. Newton said nothing about the nature of gravitational forces. Interestingly, even today their nature is still problematic.
It should be said that in classical mechanics, the question of the nature of forces, in fact, was not raised, or rather, was not of fundamental importance. Simply, all natural phenomena were reduced to the three laws of mechanics and the law of universal gravitation, to the action of forces of attraction and repulsion.
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4. Basic principles of MCM
The most important principles of MKM are:
principle of relativity,
long range principle,
principle of causality.
Galileo's principle of relativity. Galileo's principle of relativity states that all inertial reference frames (ISRs) from the point of view of mechanics are completely equal (equivalent). The transition from one ISO to another is carried out on the basis of Galilean transformations (see Fig. 2).
Let there be an IFR XYZ, relative to it along the axis it moves uniformly with a speed V 0 system XYZ. Let at the moment t = 0 the origin of coordinates O and O match. Then the coordinates M in these two systems at some point in time t will be related by:
x \u003d x "+ Vot;
y=y";
z = z".
Time flows the same everywhere, i.e. t = t", the mass of the bodies remains unchanged, i.e. m = m".
For speeds: V x \u003d Vo + V "x; V y \u003d V" y; V z \u003d V" z;
If time and speed are the same and V 0 is a constant value (from the condition), then a x = a"x , and, consequently, the forces in both systems are the same (ma x = ma x ) means that all mechanical phenomena in ISO proceed in the same way. Therefore, no mechanical experiments can distinguish rest from uniform rectilinear motion.
Long range principle. In MCM, it was assumed that the interaction is transmitted instantly, and the intermediate environment does not participate in the transmission of the interaction. This position was called the principle of long-range action.
Causality principle.As already mentioned, in MCM all the variety of natural phenomena to the mechanical form of motion of matter (mechanistic materialism, mechanism). On the other hand, it is known that there are no causeless phenomena, that it is always possible (in principle) to single out cause and effect. Cause and effect are interconnected and influence each other. The effect of one cause may be the cause of another effect. This idea was developed by the mathematician Laplace, stating the following:“Every phenomenon that occurs is connected with the previous one on the basis of the obvious principle that it cannot arise without a producing cause. The opposite opinion is an illusion of the mind.”Those. Laplace believed that all connections between phenomena are based on unambiguous laws. This doctrine of the conditionality of one phenomenon by another, about their unambiguous regular connection, entered physics as the so-called Laplacian determinism ( determinism predestination). Significant unambiguous connections between phenomena are expressed by physical laws.
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test questions
1. How can scientific pictures of the world be classified?
2. Define NCM
3. What is a paradigm?
4. Name the main physical pictures of the world and indicate the approximate time when they were formed and developed.
5. On what basic ideas is the MCM based?
6. What is an a priori judgment?
7. On what principles is the mechanical picture of the world based?
8. Explain what the principle of long-range action is.
9. Explain Galileo's principle of relativity.
10. What is the principle of causality?
Literature
1. Diaghilev F.M. Concepts of modern natural science. M.: Ed. IMPE, 1998.
2. Dubnishcheva T.Ya. Concepts of modern natural science. Novosibirsk: YuKEA Publishing House, 1997.
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Ufa State Aviation Technical University
The formation of a mechanistic picture of the world is associated with the name of Galileo Galilei, who established the laws of motion of freely falling bodies and formulated the mechanical principle of relativity. He was the first to apply the experimental method to the study of nature, together with the measurements of the quantities under study and the mathematical processing of the measurement results. If experiments were periodically set before, then it was he who began to systematically apply their mathematical analysis for the first time.
Galileo's approach to the study of nature was fundamentally different from the previously existing natural-philosophical method, in which a priori, purely speculative schemes were invented to explain natural phenomena.
Natural philosophy, is an attempt to use general philosophical principles to explain nature. Sometimes brilliant conjectures were expressed, which for many centuries were ahead of the results of specific studies. For example, the atomistic hypothesis of the structure of matter put forward by the ancient Greek philosopher Leucippus (V BC) and substantiated in more detail by his student Democritus (c. 460 BC - the year of death is not known), as well as the idea of evolution expressed by Empedocles (c. 490 - c. 430 BC) and his followers. However, after the concrete sciences gradually arose and they separated from undifferentiated knowledge, natural-philosophical explanations became a brake on the development of science.
This can be seen by comparing the views on the movement of Aristotle and Galileo. Based on the a priori natural-philosophical idea, Aristotle considered "perfect" movement in a circle, and Galileo, relying on observations and experiment, introduced the concept inertial motion.
Equivalent is the following formulation, convenient for use in theoretical mechanics: "An inertial frame of reference is called, in relation to which space is homogeneous and isotropic, and time is homogeneous." Newton's laws, as well as all other axioms of dynamics in classical mechanics, are formulated in relation to inertial frames of reference.
The term "inertial system" (German: Inertialsystem) was proposed in 1885 by Ludwig Lange and meant a coordinate system in which Newton's laws are valid. As conceived by Lange, this term was to replace the concept of absolute space, subjected to devastating criticism during this period. With the advent of the theory of relativity, the concept was generalized to "inertial frame of reference".
Inertial Reference System (ISO)- a frame of reference in which all free bodies move in a straight line and uniformly or are at rest (Fig. 2). The use of the Earth as an ISO, despite its approximate nature, is widespread in navigation.
Rice. 2. Inertial frame of reference.
The inertial coordinate system, as part of the ISO, is built according to the following algorithm. As the point O - the origin of coordinates, the center of the earth is chosen in accordance with its accepted model. Axis z coincides with the axis of rotation of the earth. axes x and y are in the equatorial plane. It should be noted that such a system does not participate in the rotation of the Earth.
According to Galileo, a body that is not affected by any external forces will move not in a circle, but uniformly along a straight path or remain at rest. Such a representation, of course, is an abstraction and idealization, since in reality it is impossible to observe such a situation that no forces act on the body. However, this abstraction mentally continues the experiment, which can be approximately carried out in reality, when, isolating from the action of a number of external forces, it can be established that the body will continue its movement as the impact of extraneous forces on it decreases.
The new experimental natural science, in contrast to the natural-philosophical conjectures and speculations of the past, began to develop in close interaction between theory and experience, when each hypothesis or theoretical assumption is systematically verified by experience and measurements. It was thanks to this that Galileo was able to refute Aristotle's earlier assumption that the path of a falling body is proportional to its speed. Having undertaken experiments with the fall of heavy bodies (cannonballs), Galileo proved that this path is proportional to their acceleration (9.81 m / s 2). Galileo discovered the satellites of Jupiter, spots on the Sun, mountains on the Moon, which undermined faith in the perfection of the cosmos.
A new major step in the development of natural science was marked by the discovery of the laws of planetary motion. If Galileo dealt with the study of the movement of earthly bodies, then the German astronomer Johannes Kepler (1571-1630) studied the movements of celestial bodies, intruding into an area that was previously considered forbidden to science.
Kepler could not turn to experiment for his research and therefore was forced to use many years of systematic observations of the motion of the planet Mars, made by the Danish astronomer Tycho Brahe (1546-1601). After trying many options, Kepler settled on the hypothesis that the trajectory of Mars, like other planets, is not a circle, but an ellipse. The results of Brahe's observations corresponded to the hypothesis and confirmed it.
The trajectory of Mars is not a circle, but an ellipse, at one of the foci of which is the Sun - a position known today as Kepler's first law. Further analysis led to second law: the radius vector connecting the planet and the Sun covers equal areas in equal time. This meant that the farther a planet is from the Sun, the slower it moves. Kepler's third law: the ratio of the cube of the average distance of the planet from the Sun to the square of the period of its revolution around the Sun is a constant value for all planets: a³ / T² = const.
The discovery of the laws of planetary motion by Kepler testified: there is no difference between the movements of earthly and celestial bodies, they all obey natural laws; the very way of discovering the laws of motion of celestial bodies does not differ in principle from the discovery of the laws of terrestrial bodies. True, due to the impossibility of carrying out experiments with celestial bodies, in order to study the laws of their motion, it was necessary to turn to observations, i.e. in close interaction of theory and observation, careful verification of put forward hypotheses by measuring the movements of celestial bodies.
The formation of classical mechanics and the mechanistic picture of the world based on it took place in two directions: generalization of the previously obtained results (the laws of motion of freely falling bodies discovered by Galileo) and the laws of planetary motion formulated by Kepler; creation of methods for the quantitative analysis of mechanical movement in general.
Newton created his own version of the differential and integral calculus directly to solve the basic problems of mechanics: the definition of instantaneous speed as the derivative of the path with respect to the time of motion and acceleration as the derivative of the velocity with respect to time or the second derivative of the path with respect to time. Thanks to this, he was able to accurately formulate the basic laws of dynamics and the law of universal gravitation. In the XVIII century. this was the greatest conquest of scientific thought.
Newton, like his predecessors, attached great importance to observations and experiments, seeing them as the most important criterion for separating false hypotheses from true ones. Therefore, he sharply opposed the assumption of the so-called "hidden qualities", with the help of which the followers of Aristotle tried to explain many phenomena and processes of nature. To say that each kind of thing is endowed with a special latent quality by which it acts and produces effects, Newton pointed out, is to say nothing.
In this regard, he puts forward a completely new principle for the study of nature, according to which to deduce two or three general principles of motion from phenomena and then to state how the properties and actions of all corporeal things follow from these obvious principles would be a very important step in philosophy, although the causes of these principles have not yet been discovered.
These principles of motion are the basic laws of mechanics, which Newton precisely formulates in his main work, The Mathematical Principles of Natural Philosophy, published in 1687.
First law which is often called the law of inertia, states that any body continues to be held in its state of rest or uniform rectilinear motion until and insofar as it is forced by applied forces to change this state. This law, discovered by Galileo, was able to show that as the impact of external forces decreases, the body will continue to move, so that in the absence of all external forces, it must remain either at rest or in uniform and rectilinear motion.
Of course, in real motions one can never completely get rid of the influence of friction forces, air resistance and other external forces, and therefore the law of inertia is an idealization in which one abstracts from a really complex picture of motion and imagines an ideal picture that can be obtained by passing to the limit, those. through a continuous decrease in the action of external forces on the body and the transition to a state where this effect becomes equal to zero.
Second Basic Law occupies a central place in mechanics: the change in the momentum is proportional to the applied acting force and occurs in the direction of the straight line along which this force acts.
Newton's third law: to action there is always an equal and oppositely directed counteraction, otherwise the interactions of two bodies against each other are equal and directed in opposite directions.
Newton believed that the principles of mechanics are established using two opposite, but at the same time interrelated methods - analysis and synthesis. Genuine hypotheses, capable of experimental verification, form the basis and starting point of all research in the natural sciences. Thanks to this, the study of mechanical processes was reduced to their exact mathematical description. For such a description, it was necessary and sufficient to specify the coordinates of the body and its velocity (or momentum mv), as well as the equation of its motion. All subsequent states of a moving body were precisely and unambiguously determined by its initial state.
Thus, by setting this state, it was possible to determine any other state of it, both in the future and in the past. It turns out that time has no effect on the change of moving bodies, so that in the equations of motion the sign of time could be reversed. Consequently, classical mechanics and the mechanistic picture of the world as a whole are characterized by the symmetry of processes in time, which is expressed in the reversibility of time.
Hence, the impression easily arises that no real changes occur during the mechanical movement of bodies. Given the equation of motion of the body, its coordinates and speed at some point in time, which is often called its initial state, we can accurately and unambiguously determine its state at any other point in time in the future or past. Let us formulate the characteristic features of the mechanistic picture of the world.
1. All states of the mechanical motion of bodies with respect to time turn out to be basically the same, since time is considered to be reversible.
2. All mechanical processes are subject to the principle of rigid determinism, the essence is the recognition of the possibility of an accurate and unambiguous determination of the state of a mechanical system by its previous state.
According to this principle, chance is excluded from nature. Everything in the world is strictly determined (or determined) by previous states, events and phenomena. When extending this principle to the actions and behavior of people, one inevitably comes to fatalism.
With a mechanistic picture, the world around us itself turns into a grandiose machine, all subsequent states of which are precisely and unambiguously determined by its previous states. This point of view on nature was most clearly and figuratively expressed by a French scientist. XVIII century Pierre Simon Laplace (1749-1827):
3. Space and time are in no way connected with the movements of bodies, they have an absolute character.
In this regard, Newton introduces the concepts of absolute, or mathematical, space and time.
Absolute space - in classical mechanics - three-dimensional Euclidean space, in which the principle of relativity and Galilean transformations is fulfilled. The term was introduced by Newton (together with the concept of absolute time) in the Principia Mathematica. For him, space and time act as a universal receptacle that has relations of order and exists independently of each other and of material bodies.
This picture is reminiscent of the ideas about the world of the ancient atomists, who believed that atoms move in empty space. Similarly, in Newtonian mechanics, space turns out to be a simple receptacle for bodies moving in it, which have no effect on it.
4. The tendency to reduce the patterns of higher forms of motion of matter to the laws of its simplest form - mechanical motion.
Mechanism, which tried to approach all processes without exception from the point of view of the principles and scope of mechanics, was one of the prerequisites for the emergence of the metaphysical method of thinking.
5. The connection of mechanism with the principle of long-range action, according to which actions and signals can be transmitted in empty space at any speed. In particular, it was assumed that gravitational forces, or forces of attraction, act without any intermediate medium, but their strength decreases with the square of the distance between the bodies. Newton left the question of the nature of these forces to be decided by future generations. All of the above and some other features predetermined the limitations of the mechanistic picture of the world, which were overcome in the course of the subsequent development of natural science.
1. Natural scientific views and methodology of Leonardo da Vinci.
3. Galeleo Galilei and the birth of experimental natural science.
4. Johannes Kepler and the discovery of the laws of celestial mechanics.
6. Successes and difficulties of the mechanical picture of the World.
Mechanical picture of the World.
1.Natural scientific views and methodology of Leonardo da Vinci.
The new science, and in particular physics, begins with Galileo and Newton.
But it, like the new culture, was not a direct continuation of the science and culture of the Middle Ages. At the turn of the 15th century. the old, medieval culture of the countries of Western and Central Europe was replaced by a new culture, the characteristic features of which were humanism, the restoration of interest in antiquity, the revival of ancient values, the rejection of scholasticism, faith in the capabilities of man and his mind.
This is the Renaissance. At this time, painting, sculpture, architecture, literature and new experimental natural science developed unusually rapidly. And among these titans of the Renaissance, one of the first should be called Leonardo da Vinci, "to whom the most diverse branches of physics owe the most important discoveries."
For Leonardo, art has always been a science. To engage in art meant for him to make scientific calculations, observations and experiments. The connection of painting with optics and physics, with anatomy and mathematics forced
Leonardo becomes a scientist. Leonardo especially appreciated mathematics.
Leonardo's mathematics is the mathematics of a constant value, it, of course, could not master the complex problems of motion. The simplicity of the mathematical apparatus and the complexity of the problems that he undertook in physics and technology, in some cases forced him to replace mathematical calculations with observation and measurement, led to the invention of many devices.
As for the views of Leonardo da Vinci on space and time, they were the same as those of Aristotle.
Very characteristic of the mechanics of Leonardo da Vinci is the desire to delve into the essence of oscillatory motion. He approached the modern interpretation of the concept of resonance, speaking of an increase in the amplitude of oscillations when the natural frequency of the system coincides with the frequency from outside.
A large place in the works of Leonardo was occupied by hydraulics. He began to study hydraulics as a student and returned to it throughout his life. Leonardo designed and partially completed the construction of a number of canals. He almost closely approached the formulation of Pascal's law, and in the theory of communicating vessels he practically anticipated the ideas of the 17th century.
Leonardo was the first and dealt a lot with flight issues. The first studies, drawings and drawings on aircraft date back to about 1487. Metal parts were used in his aircraft; the man was located horizontally, setting the mechanism in motion with his arms and legs.
He built a model glider and prepared to test it. The desire to protect a person during these tests led him to the invention of a parachute.
In the time of Leonardo da Vinci, the geocentric system of the Ptolemaic world reigned supreme. Leonardo repeatedly pointed out its failure. We can assume that Leonardo, regardless of
Copernicus came close to understanding the heliocentric system of the world.
Leonardo inquisitively observed nature, and for this reason alone he could not help but be interested in questions of geology, paleontology and agronomy.
Thus was born his theory of fossils. Leonardo is not afraid to abandon the biblical ideas about catastrophes and floods on Earth. He argues that finding fossilized shells and plants in mysterious places has nothing to do with biblical statements, but is caused by the slow movement of land and sea.
It is difficult to enumerate all the engineering problems that Leonardo's inquisitive mind worked on. He invented many types of machines for spinning, weaving and other purposes. Among his surviving records there is a description of a compass with a mobile center, an excavator, a device for a diver, and various types of drilling tools. Especially many inventions were made by Leonardo in the field of military and military engineering.
In 1502 - 1503. Leonardo da Vinci writes a letter to the Turkish Sultan, where he offers him several of his inventions and projects, including the project of a bridge across the Golden Horn Bay, which would connect Galata with
Istanbul and under which sailing ships could sail.
During the same period, Leonardo da Vinci drafted a bridge across
Bosphorus. This ball would be a huge bridge about 24 meters wide, high from the water
41 meters and a length of 350 meters, with 233 meters going over the sea, the rest
117 meters - above land. These were exceptionally bold projects and ideas that were implemented much later.
Many artists of that time, despite the strict ban of the church, studied human anatomy. Leonardo was initially interested in anatomy as an artist. He studied the muscles of the body in various positions of the arms and legs, but soon significantly expanded the scope of anatomical research: he became interested in the heart, circulatory system, and lungs; he was the first to give a correct description of the spinal column and approached the modern understanding of the role of the lungs in the body. The significance of Leonardo's anatomical work for the development of medicine is indisputable. It should be noted that Leonardo da Vinci considered the activity of the organism, its various organs, various movements from the point of view of mechanics.
One can only wonder and admire the versatility of interests and the inquisitive mind of this thinker.
Summing up the scientific activity of this giant, I would like to draw attention to his methodological views.
“Experience is the interpreter of nature. He never deceives, only our judgments are mistaken, which expect from him what he is not able to give. We must make experiments, changing the circumstances, until we extract general rules from them.
Highly appreciating the role of experience, the role of practice, Leonardo da Vinci was not a narrow practitioner, he was well aware of the need for theory:
“He who is fond of practice without science is like a helmsman who enters a ship without a rudder or compass: he is never sure where he is sailing. Always practice must be built on good theory. Science is the commander, and practice is the soldiers. Such is the methodology of knowledge of Leonard da Vinci, which has retained its value to this day.
2. Heliocentric system of the World of Nicolaus Copernicus.
The geocentric system of Ptolemy, despite the expressed doubts about its correctness and correct guesses about the movement of the Earth, lasted in science for 14 centuries. And only with the beginning of geographical discoveries, with the transition from the feudal Middle Ages to the new time, it became necessary to replace the theory of Ptolemy with a new one.
In 1506 Copernicus, having received an education (mathematics, canon law, medicine, astronomy), returned from Italy to his homeland in Poland and within 10 years formalized his ideas, born during the years of study and wandering, in the form of a scientific theory - the heliocentric system of the World. In this system
Copernicus reduced the Earth to the role of an ordinary planet, he placed the Sun in the center of the system, and all the planets, together with the Earth, moved around the Sun in circular orbits. For 16 years, Copernicus has been conducting astronomical observations of the Sun, stars and planets. In 1532, on the eve of his sixtieth birthday, he completed his life's work, On the Revolutions of the Celestial Spheres. In February 1543, the immortal creation of N. Copernicus “on the rotations of the celestial spheres” was published. But Copernicus himself saw his book only a few hours before his death (May 24, 1543). The essay “On the rotations of the celestial spheres” consists of 6 books. The first book contains all the logical and physical arguments in favor of the motion of the Earth. The second book contains elements of spherical astronomy and ends with a catalog containing the coordinates of 1025 stars. The third book contains the theory of the motion of the sun, the fourth book the theory of the motion of the moon. The most important is the fifth book, which gives a complete development of the heliocentric theory of planetary motions with all the mathematical proofs. In the sixth book, the apparent motion of the planets is set forth.
The great importance of the heliocentric system created by Copernicus
The world was discovered after Kepler discovered the true laws of the elliptical motion of the planets, and I. Newton, on their basis, the law of universal gravitation; when Le Verrier and Adams, based on the data of this system, predicted the existence and theoretically determined the location of an unknown planet (Neptune), and Galle, pointing a telescope at the point in the sky indicated by them, discovered an unknown planet. At present, the teachings of Copernicus have not lost their significance. it revealed the true picture of the World and made a revolutionary revolution "in the development of the system of scientific worldview."
3. Galileo Galilei and the birth of experimental natural science.
Galileo Galilei - the great Italian scientist, one of the founders of classical mechanics, was born on February 15, 1564, in the family of a poor Pisan nobleman. Galileo received his first education in a monastery.
At the age of seventeen, he entered the University of Pisa, first at the Faculty of Medicine, and then transferred to the Faculty of Law, where he thoroughly studied mathematics and philosophy. In 1589 Galileo was appointed professor of mathematics at the University of Pisa. During these years
Galileo is engaged in a refutation of Aristotle's teachings about the proportionality of the speed of falling to the weight of the body. To refute this doctrine, he takes two bodies, identical in shape and size (cast iron and wooden balls).
Finding relationships between the speed of fall and the time of fall, between the distance traveled and the time of fall, Galileo refuted the centuries-old delusion and proved the constancy of the acceleration of free fall. But at the university, mechanics and astronomy had to be expounded in the spirit of
Aristotle and Ptolemy. In 1592 he became a university professor in
Padua, where he worked for 18 years (until 1610). By the end of the Padua period
Galileo begins to openly oppose the Ptolemaic system -
Aristotle.
Having made a telescope with a magnification of 32 times and directed it to the sky, Galileo discovered the irregularities of the moon; The Milky Way turned out to be composed of many stars, the number of which grew with the increase in the increase in the tube; Jupiter has four moons. All this did not correspond to the teachings of Aristotle on the opposition of the earthly and the heavenly, but confirmed the Copernican system.
In 1612, Galileo publishes "Discourses on bodies in water and those that move in it", this work was directed against the mechanics of Aristotle. It is followed by Galileo's letter on sunspots. This was also a refutation of Aristotle, but it could not go unnoticed by the church, the church accuses Galileo of proving the motion of the Earth and the immobility of the Sun; they are trying to achieve a ban on the teachings of Copernicus. In 1615, Galileo went to Rome to defend himself and prevent the prohibition of the teachings of Copernicus. But March 5
1616 the teaching of Copernicus “as false and completely contrary to the Holy
Scripture” was forbidden, Galileo received an unspoken order from the Holy Inquisition to be silent. In 1623, he again travels to Rome to achieve the abolition of restrictions on his scientific activities, but he failed to achieve the official abolition of restrictions. Despite the restrictions, Galileo is preparing for publication his main work "Dialogue on the two main systems of the world: Ptolemaic and Copernican." In February 1632, the book was published, it included all the works of Galileo, everything that was created by him from 1590 to 1625. The goal of the scientist is to present not only astronomical, but also mechanical arguments in favor of the truth of the doctrine.
Copernicus.
The rotation of the Earth, according to Ptolemy, should have scattered the bodies on it; bodies during the fall would have to move not vertically, but obliquely, since they will lag behind the moving
Earth; birds and clouds should have been carried away to the west. Refuting these arguments, Galileo comes to the discovery of the law of inertia. The discovery of this law eliminated the centuries-old delusion put forward by
Aristotle, on the need for a constant force to maintain uniform motion. The modern wording of this law is as follows:
Any body retains a state of rest or uniform and rectilinear motion until the impact from other bodies takes it out of this state. Galileo defined the mechanical principle of relativity: no mechanical experiments carried out inside a closed inertial system can determine whether the system is at rest or moving uniformly and rectilinearly.
Conversations of interlocutors about various astronomical discoveries
(irregularities of the Moon, spots on the Sun, phases of Venus, satellites of Jupiter) confirms the idea of the validity of the theory of Copernicus.
The success of the "Dialogue" was amazing, like-minded people enthusiastically greet Galileo with the opening of a new era in the study of nature.
Opponents, in turn, started a rumor that under the mask of a defender
Aristotle and Ptolemy brought out by the Pope himself. The persecution of Galileo began; in September, the command of the papal inquisition was given to Galileo to appear in
Rome, but due to Galileo's illness, they give a small respite. In February 1633
Galileo arrives in Rome, during interrogation he denied that he shared
Copernican doctrine after the Inquisition declared it heretical.
Galileo stood firmly on the fact that in the discussion about the heliocentric system of the World, both writing and speaking were not forbidden, and the book itself was released with the permission of the censors. After interrogation, Galileo was arrested and imprisoned in the shackles of the Inquisition. June 22, 1633 in the church
Mary, with a large gathering of people, the last act of judgment over Galileo took place. According to the verdict, his book was banned, and he himself was subject to imprisonment, the duration of which was left to the discretion of the Holy Office. The humiliating act of judgment and renunciation greatly undermined the health of the sick Galileo, but despite not everything, Galileo mentally saw his future work “Conversations and Mathematical Proofs”, in which the ideas of the “Dialogue” were further developed. "Conversations" were completed in 1637. The book summarizes everything that Galileo did in the field of mechanics. In 1642 Galileo died. One of the great thinkers, a great astronomer, mechanic, physicist, mathematician, has passed away.
Galileo is considered one of the founders of experimental natural science and new science. It was he who formulated the requirements for a scientific experiment, consisting in the elimination of side circumstances, in the ability to see the main thing. By experiment, Galileo refuted the teachings of Aristotle about the proportionality of the speed of falling to the weight of the body, showed that air has weight and determined its density. He was the first to point a telescope at the sky for scientific purposes, thereby expanding the scope of knowledge. Thought experiments of Galileo are built on the idealization of the movement of balls, carts and other material objects horizontally and on an inclined plane. The thought experiment later became widespread in physics and became the most important method of cognition; it was used by Maxwell when creating the theory of the electromagnetic field.
Thought experiments have allowed many scientists (Maxwell, Boltzmann,
Carnot and others) to establish regularities in chaotic thermal motion and thermodynamics. Thus, both the principle of relativity of Galileo, which was further developed in the theory of relativity, and the thought experiment, introduced into science by him and became a necessary method of modern physics, testify to the extremely high methodological level at which the great Italian scientist stood in his research.
4. Johann Kepler and the discovery of the laws of celestial mechanics.
Johannes Kepler was born on December 27, 1571, his father, Heinrich Kepler, a ruined nobleman, served as a simple soldier, his mother, the daughter of a village innkeeper, could not read and write. At birth, the boy miraculously survived. When he was four years old, his parents abandoned him, at the age of 13 he died for the third time, but life did not leave him.
After graduating from the monastery school in 1579, Kepler transferred to a three-year theological school, after which he remained at the Tübingen Seminary, and after that at the University of Tübingen. At the university, he became acquainted with the teachings of Copernicus, becoming his ardent supporter. While working as a teacher of mathematics and philosophy at the Graz College, he, along with teaching, began to engage in scientific work in astronomy, as well as draw up calendars and horoscopes. Kepler was forced to study astrology in order not to die of hunger, to feed his family and conduct research in astronomy.
During his life, Kepler wrote many works. His first book, published in 1597, came out under the interesting title The Cosmographic Mystery. Kepler set the task of finding the numerical relationships between the orbits of the planets. Trying various combinations of numbers, he came up with a geometric scheme by which it was possible to find the distances of the planets from the Sun.
Kepler sent his work to the Danish astronomer Tycho Brahe and G. Galileo.
Because of persecution by the Catholic Church, life at home has become unbearable, and Kepler travels to Prague. There he was appointed imperial mathematician and was to work under Tycho Brahe, the imperial astronomer. In 1601, Tycho Brahe dies, and in the hands of Kepler was the journal of thirty years of observations of the "king of astronomy."
In 1609, Kepler's book The New Astronomy, or
Celestial physics with comments on the movement of the planet Mars according to observations
Quiet Brahe. For eight years he worked on calculations, seventy times he had to repeat each calculation, but, in spite of everything, he formulated the first two laws of planetary motion:
1. All planets move in ellipses, in one of the focuses of which is the Sun.
2. The radius vector drawn from the Sun to the planet describes equal areas in equal time intervals.
Need and misfortune continue to haunt him, in 1611 his wife and son died, and he was left with two children in his arms. Material need forced him to leave Prague, and he went to Linz, where he took the place of a mathematics teacher. In 1615, he receives news of his mother being accused of witchcraft. He spends all his strength and resourcefulness to save his mother from the fire, in 1621 he achieves her release. Even after such blows of fate, the strength of the spirit does not leave him, and he publishes a new work, "The Harmony of the World", containing the third law of celestial mechanics: the squares of the periods of the planets are related as the cubes of the semi-major axes of their orbits.
Kepler's other most famous works are: "Rudolf Tables"
- astronomical planetary tables, on which Kepler worked for 20 years. They were named after Emperor Rudolph 2. These tables served sailors and astronomers, calendar compilers and astrologers, and only in
19th century were replaced by more accurate ones. With my work in mathematics
Kepler made a great contribution to the theory of conic
Sections, in the development of the theory of logarithms, contributed to the development of integral calculus and the invention of the first computer.
In 1618 the Thirty Years' War begins. The treasury is still empty Kepler lives by odd jobs, making numerous trips to
Regensburg with troubles about issuing a salary. During one of these trips, Kepler fell ill and died. In 1774, the St. Petersburg Academy of Sciences bought a large part of the Kepler archive.
This remarkable man and great scientist in his homeland, in
Vejle and Regensburg, erected a monument and opened museums. Kepler is destined to immortality as a reward for his perseverance and ingenuity, with which he renewed his attempts to unravel the mysteries of Nature, for the laws of planetary motion he discovered.
In 1996, 425 years have passed since the birth of one of the greatest astronomers in the world, Johannes Kepler.
5. Mechanics and methodology of Isaac Newton.
In 1987, 300 years have passed since the publication of the outstanding work of Cambridge University Professor Isaac Newton
"The Mathematical Principles of Natural Philosophy".
In his fundamental work, which contains 700 pages in Russian translation, the brilliant English physicist, astronomer and mathematician outlined the system of laws of mechanics, the law of universal gravitation, gave a general approach to the study of various phenomena based on the "method of principles", i.e. The work was not only of great scientific, but also of great methodological significance. For Newton, the legacy of his predecessors was very important:
"If I have seen further than others, it is because I have stood on the shoulders of giants."
Galileo and Kepler should be mentioned first of all among these giants.
At 27, he became a professor at the University of Cambridge.
In his work on optics, Newton posed a very important and difficult question: "Are not rays of light very small particles emitted by luminous bodies?" And the expiration hypothesis, and then the corpuscular theory, unconditionally recognized by his followers and supported by the authority of Newton, which dominated optics in the 18th century. Many did not agree with this theory. on its basis it was impossible to explain the interference and diffraction of light. In the theory of light, Newton wanted to combine corpuscular and wave representations. On this occasion,
Newton had two interesting thoughts:
1. On the possible transformation of bodies into light and back. In 1933-1934. the facts of the transformation of an electron and a positron into gamma quanta were first discovered
(photons) and the birth of an electron and a positron in the interaction of a photon with charged particles. This is a fundamental discovery of modern elementary particle physics.
2. On the influence of bodies on the propagation of light.
The pinnacle of Newton's scientific creation is the "Beginnings ..". Approximately two and a half years of hard work cost Newton the preparation of the first edition of "Beginnings ..". The book consisted of three parts: the first two set out the laws of motion of bodies, the third part was devoted to the system
Peace. For the first edition, Newton wrote his own preface, where he speaks of the tendency of contemporary natural science to "subordinate the phenomena of nature to the laws of mathematics." Next, Newton formulates the purpose of the work and the tasks of physics: “We offer this essay as the mathematical foundations of physics. The whole difficulty of physics lies in recognizing the forces of nature by the phenomena of motion, and then, using these forces, to explain all other phenomena, ”he managed to cope with this difficult task. As the first law of mechanics, Newton took the law of inertia discovered by Galileo, formulating it more strictly. The core of mechanics is the second law, which relates the change in the body's momentum to the force acting on it, i.e. the change in the momentum of the body per unit time is equal to the force acting on it and occurs in the direction of its action. In the third law of mechanics, it was reflected that the action of bodies always has the character of interaction and that the forces of action and reaction are equal in magnitude and opposite in direction. The fourth law was the law of universal gravitation. Having stated the position on the universal nature of the forces of gravity and their identical nature on all planets, showing that “the weight of a body on any planet is proportional to the mass of this planet”, establishing the experiment of the proportionality of the mass of the body and its weight (gravity),
Newton concludes that the gravitational force between bodies is proportional to the masses of these bodies.
Even before Newton, many scientists believed that the gravitational force is inversely proportional to the square of the distance, but only Newton was able to logically substantiate and convincingly prove this universal law using the laws of dynamics and experiment. The establishment of proportionality between mass and weight meant that mass is not only a measure of inertia, but also a measure of gravity.
In the third part of the book, the scientist outlined the general system of the World and celestial mechanics, the theory of compression of the Earth at the poles, the theory of tides, the movement of comets, perturbations in the movement of planets, etc., based on the law of universal gravitation. The theory of gravitation caused philosophical discussions and needed further proof. The first was the question of the shape of the Earth. According to Newton's theory, the Earth was compressed at the poles, according to the theory
Descartes - extended. Disputes were resolved as a result of measuring the arc of the earth's meridian in the equatorial zone (Peru) and in the north (Lapland) by two expeditions of the Paris Academy of Sciences. The theory turned out to be true
Newton.
Newton's works reveal his methodology and worldview of research. Newton was convinced of the existence of matter, space and time, of the existence of objective laws of the world accessible to human knowledge. With his desire to reduce everything to mechanics, Newton supported mechanistic materialism (mechanism). Despite his great achievements in the field of natural science, he deeply believed in God and took religion very seriously. He believed that “the wisdom of the Lord is revealed equally in the structure of nature and in sacred books. To study both is a noble deed.” Newton was the author of "Commentary on the Book of the Prophet Daniel", "Apocalypse", "Chronology". From this we can conclude that for Newton there was no conflict between science and religion, in his worldview both coexisted.
Newton himself characterizes his method of cognition as follows:
“To derive two or three general principles of motion from phenomena, and then to state how the properties and effects of all corporeal things follow from these manifest principles, would be a very important step in philosophy, even if the causes of these principles were not yet discovered.” By principles, Newton means the most general laws underlying physics. This method was later called the method of principles, Newton outlined the requirements for research in the form of 4 rules:
1. Must not accept other causes in nature than those that are true and sufficient to explain the phenomena.
2. It is necessary to attribute the same causes to the same phenomena.
3. The properties of bodies subjected to investigation, which are independent and unchanging during experiments, must be taken as the general properties of material bodies.
4. Laws found inductively from experience must be considered true as long as they are not contradicted by other observations.
Since the principles are established by studying the phenomena of nature, they are at first hypotheses, from which, by logical deduction, consequences are obtained that are verified in practice.
Therefore, the method of Newton's principles is a hypothetical-deductive method, which in modern physics is one of the main ones for building physical theories. Newton's method was highly appreciated in the methodological statements of many scientists, including A. Einstein and
S.I. Vavilov, but many scientists also believed that principles and hypotheses are derived directly from experience. Consequently, a theory is deduced directly from experience by means of formal logic, which has only the goal of connecting some experimental data with others.
A lot of questions and disputes in the history of physics have been caused by the views
Newton on space and time. Newton proceeds from the fact that in practice people cognize space and time by measuring the spatial relationships between bodies and the temporal relationships between processes.
Newton calls the concepts of space and time worked out in this way relative. He admits that in nature there exist absolute space and time independent of these relations, as empty receptacles of bodies and events. Space and time, according to Newton, do not depend on matter and material processes, which is not consistent with the ideas of physics of the 20th century. Since Newton's matter is inert and incapable of self-motion, and the empty absolute space is indifferent to matter, he recognizes the "first impulse", that is, God, as the primary source of motion.
Newton - this brilliant genius - indicated, according to Einstein, the ways of thinking, experimental research and practical constructions, created brilliant methods and mastered them perfectly, was exceptionally inventive in finding mathematical and physical proofs, was placed by fate itself at a turning point in the mental development of mankind . Modern physics has not discarded Newton's mechanics, it has only set the limits of its applicability.
6. Successes and difficulties of the MKM
MKM was formed under the influence of metaphysical materialistic ideas about matter and forms of its existence. The fundamental ideas of this picture of the World are classical atomism and mechanism.
The core of the MCM is Newtonian mechanics, in any physical theory there are quite a lot of concepts, but there are basic ones in which the specificity of this theory, its basis, its ideological aspect is manifested. These concepts include: matter, motion, space, time, interaction. Matter is a substance consisting of the smallest, further indivisible, absolutely solid moving particles (atoms), i.e. in the MKM, discrete concepts of matter were adopted. And therefore, the most important concepts in mechanics were the concepts of a material point and an absolutely rigid body, a material point is a body whose dimensions can be neglected under the conditions of a given problem. An absolutely rigid body is a system of material points, the distance between which remains unchanged.
Space. Aristotle denied the existence of empty space, linking space, time and movement. Atomists, on the other hand, recognized atoms and empty space in which atoms move.
Newton considers two forks of space: the relative one, which people get acquainted with by measuring the spatial relations between bodies, and the absolute one is an empty receptacle of bodies, it is not connected with time and its properties do not depend on the presence or absence of material objects in it. It is three-dimensional, continuous, infinite, homogeneous, isotropic. Spatial relations are described in the MCM by Euclid's geometry.
Time. Newton considers two types of time: relative and absolute. Relative time is known in the process of measurement.
“Absolute, true, mathematical time in itself and in its very essence, without any relation to anything external, flows evenly and is otherwise called duration.” Thus, time is an empty receptacle of events, not dependent on anything, it flows in one direction (from the past to the future), it is continuous, infinite and everywhere the same (homogeneous).
Traffic. Only mechanical movement was recognized in MKM, i.e. change in the position of the body in space over time. It was believed that any complex movement can be represented as the sum of spatial displacements (the principle of superposition). The motion of any body was explained on the basis of Newton's three laws.
It should be noted that in mechanics the question of the nature of forces was not of fundamental importance. For its laws and methodology, it was enough that force is a quantitative characteristic of the mechanical interaction of bodies. She simply sought to reduce all natural phenomena to the action of forces of attraction and repulsion, encountering insurmountable difficulties along the way.
The most important principles of MCM are the principle of relativity of Galileo, the principle of long-range action and the principle of causality. The principle of relativity
Galileo claims that all inertial reference systems (ISRs) are completely equal (equivalent) from the point of view of mechanics. The transition from one inertial frame to another is carried out on the basis of transformations
Galileo.
In MCM, it was assumed that the interaction is transmitted instantly and the intermediate medium does not participate in the transmission of the interaction.
This position bears the principle of long-range action.
As you know, there are no causeless phenomena, you can always distinguish cause and effect, cause and effect are interconnected and influence each other. An effect may be the cause of another phenomenon. “Every phenomenon that occurs is connected with the previous one on the basis of the obvious principle that it cannot arise without a producing cause.” In nature, there may be more complex relationships:
1. The same effect may have different causes, for example, the conversion of saturated vapor into liquid due to an increase in pressure or due to a decrease in temperature.
2. In thermal motion, for example, the speed, kinetic energy, momentum of an individual particle change without changing the macro parameters
(temperature, pressure, volume) characterizing the system as a whole. As a result of the development of thermodynamics and statistical physics, a number of important laws were discovered, including the conservation and transformation of energy for thermal processes (the first law of thermodynamics) and the law of the increase in entropy in isolated systems (the second law of thermodynamics).
Thermodynamics is a branch of physics that studies the laws governing the transition of energy from one form to another. The first law of thermodynamics states: The heat communicated to the system is spent on changing its internal energy and on the system doing work against external forces.
From the point of view of the first law of thermodynamics, any processes can take place in the system, so long as the law of conservation and transformation of energy is not violated.
All real processes are irreversible, since the presence of friction forces necessarily leads to the transition of an ordered motion into a disordered one. To characterize the state of the system and the direction of the flow of processes, a special state function, entropy, was introduced in physics. It turned out that the entropy of a closed system cannot decrease.
The closure of the system means that the processes in it proceed spontaneously, without external influence. In the case of reversible processes (and they do not exist in reality), the entropy of a closed system remains unchanged, in the case of irreversible processes, it increases. Thus, in reality, the entropy of a closed system can only increase, this is the law of the increase in entropy (one of the formulations of the second law of thermodynamics). This law is of great importance for the analysis of processes in closed macroscopic systems. The statistical nature of this law means that it is more fundamental than dynamic laws.
In modern physics, probabilistic-statistical ideas are widely used (statistical physics, quantum mechanics, evolution theory, genetics, information theory, planning theory, etc.). Undoubtedly, their practical value is also: product quality control, checking the operation of an object, assessing the reliability of the unit, organizing mass service. But neither thermodynamics nor statistical physics have been able to radically change the concept of
MKM, destroy it: MKM has changed and expanded its boundaries.
The development of physics until the middle of xlxc proceeded mainly within the framework of Newtonian views, but more and more new discoveries, especially in the field of electrical and magnetic phenomena, did not fit into the framework of mechanical concepts, i.e. The MKM became a brake on new theories, and the need for a transition to new views on matter and motion was brewing. It was not the MCM itself that turned out to be untenable, but its original philosophical idea - mechanism. In the bowels of the MKM, elements of a new - electromagnetic - picture of the World began to take shape.
All that has been said about the mechanical picture of the World can be summed up in the following conclusions:
1. Impressive advances in mechanics led to mechanism and the idea of the mechanical essence of the World became the basis of the worldview. Indivisible atoms formed the basis of Nature. Living beings are "divine machines" operating according to the laws of mechanics. God created the World and set it in motion.
2. Molecular physics developed within the framework of the MCM. The idea of heat was formed in two directions: as the mechanical movement of particles and as the movement of weightless, imperceptible "fluids" (caloric, phlogiston).
On the basis of electrical magnetic "fluids", mechanics sought to explain electrical and magnetic phenomena, on the basis of fluid
"life force" tried to understand the work of living organisms.
3. Analysis of the operation of heat engines led to the emergence of thermodynamics, the most important achievement of which was the discovery of the law of conservation and transformation of energy. But in the MKM, all types of energy were reduced to the energy of mechanical motion. The macrocosm and the microcosm obeyed the same mechanical laws. Only quantitative changes were recognized. This meant the absence of development, that is, the world was considered metaphysical.
Bibliography:
1. Diaghilev F.M. "Concepts of modern natural science"
2. Solopov E.F. "Concepts of modern natural science"
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A series: Lecture notes
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Mechanical picture of the world
Man received the first knowledge about nature in primitive society. This was knowledge revealed as a result of systematic observation of the same phenomena and the same properties of objects or obtained as a result of life experience (wood does not sink, stone sinks, hot fire, cold ice, etc.). The knowledge of the ancient people was unscientific, they were not systematized in any way and had no theoretical basis, but concerned only everyday observations and everyday experience.
In the countries of the Ancient East (Mesopotamia, Egypt), knowledge had a broader form, there were sciences, but they were woven together with mystical and religious aspects. The real birthplace of the natural sciences is Greece (VI-IV centuries BC). Greek science was rational (it did not resort to the help of religion and mysticism to explain the facts) and systemic (it began to classify phenomena and objects of study).
The development of science was facilitated by the special structure of the Greek city-states - with democratic standards of life and an abundance of social laws. A similar method of organization was applied in the field of knowledge: if human society obeys laws, then nature must obey its own laws. Features of the slave-owning mode of production gave four priority occupations in Greek society - politics, war, art, philosophy; Philosophy was understood as a nascent science. Contemplation and an abstract-speculative view of the world formed the two main principles of Greek science: thinking in concepts and the creation of comprehensive philosophical theories.
The scientific research of the Greeks had no practical significance, it was a movement of pure philosophical thought: the planimetry of Hipparchus, the geometry of Euclid, the aporias of the Eleatics, the Diogenesian search for the essence of man. The purpose of scientific knowledge was to study the process of transformation of the initial Chaos into the Cosmos. So the works of Thales, Anaximander, Heraclitus, Diogenes appeared. They recognized the human mind as the only tool of knowledge. The Greeks achieved great success in mathematics (Pythagoras, Euclid, Plato), in the doctrine of the atom (Democritus, Leucippus), in the doctrine of the indestructibility of matter (Empedocles), but Aristotle created natural science as a scientific program.
Aristotle was the author of numerous works on nature - "Physics", "On the Sky", "Meteorology", "On the Origin of Animals", etc. For the first time in the world, he drew attention to the laws of motion of physical bodies and thus gave rise to the branch of physics - mechanics. Traffic Aristotle defined as a change in the position of the body in space, Aristotle's space was filled with transparent matter, similar to air. He owns the saying “nature is afraid of emptiness”, that is, space is filled with the likeness of ether. Movement is created without a cause of movement; a self-propelled body has a source of movement in itself. He distinguished between natural and violent movement, local (for heavy bodies) and fiery (for light ones).
In reasoning, Aristotle introduced power concept, which includes three main types of force - traction, pressure and impact. Considering a complex rotational motion, he deduced the definition of the moment of force, and for the natural fall of the body he derived the law V = F / w, where V is the speed, F is the force of the body's tendency to its natural place, w is the air resistance. According to Aristotle's law, the speed of a body's fall depended on its mass. This view lasted until the time of Galileo. That is, heavy bodies, due to their mass, rush to the earth (natural place), and light bodies, because of their lightness, rush to the fiery ether, located behind a layer of air, high up to the sky, to fire.
He excluded celestial bodies from the "earthly" principles of motion: they move in a perfect circle and do not require force to move. Celestial bodies obey celestial laws (their movements are eternal and unchanging, have no beginning and end), inapplicable to earthly bodies, imperfect by nature. Imperfect terrestrial bodies can move only with the application of an external force; other bodies serve as sources of motion for them.
Aristotle believed that movement exists forever and that the first movement in the world gave rise to the prime mover, by which he understood God. He understood physical interaction as the application of the force of the motive to the movable (that is, the action is purely one-sided).
Aristotle's ideas about mechanics lasted until the time of Galileo. Galileo created a new mechanics that rejected the principles of Aristotle. He established physical laws for the motion of bodies, introduced definitions for force, speed, acceleration, uniform motion, inertia, the concepts of average speed and average acceleration, for the first time compared the concept of force with the mathematical concept of a vector (when determining the nature of motion depending on the applied force, he proceeded from the direction of this force or the interaction of forces), formulated four axioms of mechanics (two about free fall, one about inertia and one about the relativity of motion):
1. Law of inertia. Free movement along a horizontal plane occurs at a constant speed in magnitude and direction.
2. A freely falling body is moving With constant acceleration, and the final velocity of a body falling from rest is related to the height that has been traveled so far.
3. The free fall of bodies can be considered as the movement on an inclined plane, and the law of inertia corresponds to the horizontal plane.
4. Inside a uniformly moving (so-called inertial) frame all mechanical processes proceed in the same way as inside a resting one.
He derived the principle of relativity in 1632 with the help of thought experiments, by abstraction. The principle assumes that the trajectory of a falling body deviates from the vertical due to air resistance and in airless space the body will fall exactly above the point from which the fall began.
Physical laws for the mechanical picture of the world were formulated by Isaac Newton.
I law, or law of inertia, discovered by Galileo: every body retains a state of rest or uniform rectilinear motion until it is forced to change it under the action of some forces.
II law: the change in the momentum of the body per unit time is equal to the force acting on it and occurs in the direction of its action. F = m and ·ā, where F is the driving force, ā is the acceleration, and m and is the inertial mass.
Newton's second law connects the change in the body's momentum (momentum) with the force acting on it and is the core of mechanics. The law was revolutionary for its time, but inapplicable in modern physics, since Newton believed that mass does not depend on speed. Newton considered mass as a measure of inertia, and acceleration and inertia as equal in magnitude counteractions directed in opposite directions, that is, the more massive the body, the less acceleration can be given to it.
III law: The action and reaction forces are equal in magnitude and opposite in direction.
IV law, formulated by Newton is the law of universal gravitation: the force of gravity is inversely proportional to the square of the distance:
F gr = γ · m gr · M gr /r 2 , where γ is the gravitational constant.
He deduced the law from the assumption that the same force acts on the Moon moving in the Earth's orbit and on the stone falling to the Earth: the Moon gravitates towards the Earth and the force of gravity constantly deviates from rectilinear motion and is kept in its orbit. From this assumption, he calculated the gravitational force constant, or gravitational constant. According to modern calculations, the gravitational constant is:
G \u003d (6.673 ± 0.003) 10 -11 nm 2 kg -2.
Newton was of the opinion mechanistic materialism(that is, he sought to explain the laws of physics based on the objective existence of matter, space and time), although he was a religious man in the spirit of his era and even wrote a theological essay in his declining years. In an attempt to define more precisely the methods of his approach to scientific research, Newton deduced four fundamental principles:
1. It should not accept other causes in nature beyond those that are true and sufficient to explain the phenomena (repeating the famous principle of Occam's razor).
2. The same causes should be attributed to the same phenomena.
3. The properties of bodies subjected to investigation, which are independent and unchanging during experiments, must be taken as the general properties of material bodies.
4. Laws inductively derived from experience must be considered true as long as they are not contradicted by other observations.
This method is called today hypothetical-deductive and is used in modern physics.
Newton left an indelible mark not only in mechanics. Of great importance were his research in the field of optics, which immediately received worldwide recognition and became fundamental for several centuries. Newton believed that light consists of the smallest particles, which he called corpuscles, so the corpuscular theory of light arose. The theory did not explain some phenomena - for example, the interference and diffraction of light, since these are wave processes.
Newton understood the incompleteness of the corpuscular theory and was going to combine it with the wave theory, which, in fact, happened only in the 20th century, when the wave theory that replaced the corpuscular theory was also unable to explain all the phenomena.
Newton also made an application for the theory of the possibility of turning bodies into light and light into bodies, which was discovered by scientists for ultra-small particles only in the 20th century, and the theory of the influence of bodies on the propagation of light, which was experimentally proven by Einstein and formed the basis of the general theory of relativity. The great merit of the followers of Newton was the introduction of the methods of integral-differential calculus into physics and the creation of a mechanical picture of the world.
The mechanical picture of the world was based on a materialistic theory based on classical atomism, the ancestor of which was Democritus. For its time, it was undoubtedly an advanced and scientific picture of the world. It was based on the works of Galileo and Newton. The previously prevailing natural-philosophical picture of the world was based on observation as the only method of studying the world.
The mechanical picture of the world brought the experiment to the fore. Experiments began to be accompanied by a mathematical apparatus, accurate calculations, and the invention of the telescope and microscope made it possible to look into worlds that were out of proportion to the environment. Newton developed the laws of classical mechanics for the physics of the surrounding world, Kepler - the laws of celestial mechanics for the Universe, Leeuwenhoek led biology to microscopic forms, etc.
The development of classical mechanics went in two directions:
1) as a generalization of Galileo's laws and Kepler's studies;
2) as a transition to new methods of quantitative analysis of mechanical motion. Matter in this system seemed divisible only to the level of an atom, space - empty (obviously, for the possibility of moving indivisible atoms), time - empty and unidirectional (from the present to the future), movement - mechanical (changing the position of the body in space over time); all interactions were reduced to the three laws of mechanics and the law of universal gravitation, to the action of forces of attraction and repulsion.
To principles of the mechanical picture of the world include the principles of relativity, long-range action, causality.
The principle of relativity was first formulated by Galileo and said that all inertial frames of reference are equal and the transition from one system to another occurs with the help of special transformations developed by Galileo. In the inertial systems of Galileo, time flows the same everywhere, and the mass of the body is unchanged. Constant time with a constant mass corresponds to a constant speed, and if all these parameters are unchanged, then the forces in both systems are the same and all mechanical phenomena proceed in the same way. The conclusion that Galileo made on the basis of reasoning and calculations is the following: rest cannot be distinguished from uniform rectilinear motion by any experiments (corresponding, of course, to the mechanical picture of the world).
Long range principle was developed within the framework of mechanistic materialism with indivisible atoms and empty space: interaction is transmitted instantly, and the intermediate medium does not participate in the transmission of interaction. An empty medium, of course, could not take any part in the transmission of interaction, and bodies were considered as material points that, under the influence of an applied force, instantly moved in a void.
Principle of Causality was developed by the mathematician Laplace and said: every occurring phenomenon is connected with the previous one on the basis of the obvious principle that it cannot arise without a producing cause. The opposite opinion is an illusion of the mind.
Laplace's principle was called Laplacian determinism and assumed the existence of connections between phenomena on the basis of unambiguous laws; it was fixed in mechanistic physics as the principle that any fundamental connection between phenomena can be expressed by a physical law, the existence of complex connections was not understood by this picture of the world. There is matter, there is mechanical movement, there is a reason for it, there is a consequence. It remains to pass the law.
These principles turned into nothing when it became clear that the space between bodies is not empty, that the bodies themselves are not material points at all, but have mass, that phenomena are complex, irreducible to one cause and one effect.
Mechanical materialism took from Greek philosophy the idea of the materiality of the world and its divisibility to the ultimate threshold - atoms. Matter was considered discrete, and the concepts of a material point and an absolutely rigid body came to the fore. By definition, material point was a mathematically abstract body, the dimensions of which can be neglected, and absolutely rigid body, respectively, a system of material points, the distance between which always remains unchanged. Roughly speaking, a material body is a real body divided to the limit, that is, an atom, and an absolutely solid body is an object devoid of all its qualities and properties.
At the same time, the existence of an ideal model of all things (the idea of Plato) was rejected, because then one would have to admit the existence of a single plan for the construction of the material world, and this was tantamount to introducing the idea of God into the natural sciences.
Space in mechanistic materialism was considered only as an extension that can be measured. Unlike the world of objects, where the presence of matter was obvious, space was considered a container of emptiness in which material objects could move.
The space was distinguished by the fact that it was devoid of atomic structure. It was absolute, that is, mathematically empty. It existed outside of time and was necessary to move bodies or atoms.
Time and movement in the mechanical picture of the world are absolute concepts. Although Newton considered two kinds of time- relative, which is perceived by people in the measurement process, and absolute- that is, mathematical, which exists independently of external causes, does not affect anything, is uniform in nature and differs only in duration, the mechanical picture of the world has learned only absolute mathematical time.
If space was considered an absolutely empty receptacle for moving bodies and atoms, then time was the same empty receptacle for ongoing events. The movement of time went in one direction - from the past to the future.
Movement in the mechanical world was the mechanical movement of material points or absolutely rigid bodies. Complex movements in mechanics were described as the sum of simple movements from one point in space to another. The laws discovered by Newton were used to describe these movements. Mechanics introduced the concept of mass and force into science, and the mass was considered constant for a particular body and expressed its inertia, and force was understood as the cause of a change in mechanical motion and the cause of deformation. Any movement according to Newton's laws could be described in terms of applying a given force to a certain mass.
Later Descartes introduced the concept of momentum (the product of mass and speed). Descartes perceived the world around him as a mathematical given: he considered matter as a simple extension with geometric characteristics that exists because there is movement. Descartes formulated the physical concepts of force impulse and the law that states that the momentum of a force, equal to the product of the applied force and the time of its action F dt, gives the constancy of the momentum m V, that is, m V = F dt.
In this definition, the only value that can change is duration (with constant mass, uniform speed and force). Perceiving the material world as a mathematical model, Descartes developed a well-known coordinate system (X, Y, Z), which received his name.
In classical mechanics, the concept interactions (modern science divides the weak, strong, electromagnetic and gravitational) was based on the well-known laws of Newtonian mechanics and the law of universal gravitation, operating with the concepts of forces of attraction and repulsion, that is, in fact, the issue of interaction was not considered by classical mechanics.
In the mechanical picture of the world, it was not needed: all types of movements could be reduced to a simple change in the position of the body in space. Interactions were understood as the application of the forces of one body to another to change the trajectory of movement or to bring this body out of rest. Mechanics did not know any kind of movement other than mechanical (translational) and rotational (as movement in a circle), and the only interaction that was considered deeper was the force of gravity discovered by Newton.
gravity described as a mechanical movement, but derived from the movement of the megaworld. According to the law of universal gravitation, if the mass of one of the bodies and the force of gravity are known, the mass of the second body can also be determined. From the gravitational law, Newton derived the identity of the gravitational mass and the mass of inertia. Einstein called this principle the fundamental law of nature and laid the foundation for the general theory of relativity.
The following excerpt from the book Concepts of modern natural science (T. V. Karpova, 2010) provided by our book partner -
Page 39 of 42
Mechanical picture of the world
The mechanical picture of the world was formed as a result of the scientific revolution of the 16th–17th centuries. G. Galileo, I. Kepler, R. Descartes, P. Laplace, I. Newton and many other scientists contributed to its formation.
The ideas and laws of mechanics, which became the most developed branch of physics, formed the basis of new ideas of the science of the world. In fact, it is mechanics that is the first fundamental physical theory. The basis of the mechanical picture of the world was atomism, which the whole world, including man, understood as a collection of a huge number of indivisible particles - atoms moving in space and time in accordance with a few laws of mechanics. This is a corpuscular representation of matter.
The laws of mechanics, which regulated both the movement of atoms and the movement of any material bodies, were considered the fundamental laws of the universe. Therefore, the key concept of the mechanical picture of the world was the concept of motion. Bodies have an internal innate property to move uniformly and rectilinearly, and deviations from this movement are associated with the action of an external force (inertia) on the body. Mass is the measure of inertia. Gravity is a universal property of bodies.
Solving the problem of the interaction of bodies, Newton proposed the principle of long-range action. According to this principle, the interaction between bodies occurs instantly at any distance, without any material intermediaries.
The concept of long-range action is based on the understanding of space and time as special media containing interacting bodies. Newton proposed the concept of absolute space and absolute time. Absolute space was represented as a big "black box", a universal receptacle for all material bodies in nature. But even if all these bodies suddenly disappeared, absolute space would still remain. Similarly, in the image of a flowing river, absolute time was represented. It became the universal duration of all processes in the Universe. Both absolute space and absolute time exist completely independently of matter.
In the mechanical picture of the world, any events were rigidly predetermined by the laws of mechanics. Randomness, in principle, was excluded from the picture of the world.
Life and mind in the mechanical picture of the world did not have any qualitative specifics. Therefore, the presence or absence of a person in the world did not change anything. If a person once disappeared from the face of the Earth, the world would continue to exist, as if nothing had happened.
Based on the mechanical picture of the world in the XVIII - early XIX century. terrestrial, celestial and molecular mechanics were developed. Technological development proceeded at a rapid pace. This led to the absolutization of the mechanical picture of the world, and it began to be regarded as universal.
At the same time, empirical data began to accumulate in physics that contradicted the mechanical picture of the world. So, along with the consideration of nature as a system of material points, which fully corresponded to the corpuscular ideas about matter, it was necessary to introduce the concept of a continuous medium. It was needed to explain light phenomena. This is how the concept of ether appeared in physics - a particularly thin and absolutely continuous light matter. These were no longer corpuscular, but continual ideas about matter.
In the 18th century, the doctrine of imponderable substances appeared. Within its framework, the concepts of electric and magnetic fluids, caloric, phlogiston were introduced. They were also special varieties of solid matter. This was required by the mechanistic nature of classical science, which extended the principles and approaches of mechanics to other branches of science.
Thus, although the mechanical approach to these phenomena was not fully justified, the experimental facts were artificially adjusted to fit the mechanical picture of the world.
In the 19th century, a crisis occurred in physics, which was caused by research and discoveries in the field of electricity and magnetism. Then it became clear that the contradictions between the experimental data and the mechanical picture of the world became too sharp. Physics needed a significant change in their views of the world.
| Table of contents |
|---|
| The system of natural sciences and the natural-scientific picture of the world. |
| Didactic plan |
| Foreword |
| Thematic review |
| Basic natural sciences |
| The scientific method of knowing nature |
| Elements of the scientific method of cognition |
| Pseudoscience |
| Fundamental and applied sciences. Technology |
| Scientific knowledge in the Ancient East |
| The emergence of science in ancient Greece |
| ancient science |
| Mathematical program of Pythagoras - Plato |
| Atomistic program of Leucippus and Democritus |
| Aristotle's continuum program |
| The development of science in the Hellenistic era |
| Scientific knowledge in the Middle Ages |
| The main features of the medieval worldview and science |
| The Renaissance: a revolution in worldview and science |
| The discoveries of Copernicus and Bruno - the foundation of the first scientific revolution |
| Galileo Galilei and his role in the development of classical science |
| The further course of the scientific revolution |
| Isaac Newton and the completion of the scientific revolution |
| Classical science of modern times |
