This rather difficult to understand principle was formulated, first of all, as an argument for explaining some complex relationships between phenomena occurring in the world, including for explaining the very fact of its origin and development. The initial hypothesis for its explanation is the assertion that the world appears to us exactly as we see it, because we arose and are present in it as an observer. From the point of view of natural science, the anthropic principle is intended to explain what relationships should develop between fundamental physical and chemical parameters in order to contribute to the emergence of intelligent life.
The term "anthropic principle" was first used in 1973 by the British physicist B. Carter. However, after its publication, many scholars noted that a similar idea had been formulated earlier in somewhat different interpretations. In particular, it was first voiced as an anthropic principle in cosmology back in 1955 in the USSR on scientific conference on extragalactic astronomy. Among the scientists who proposed this idea were the Soviet scientists G. M. Idlis, A. L. Zelmanov, and the American R. Dicke.
But it was Carter's work that became the subject of general attention and laid the foundation for a detailed scientific understanding of this principle and its role in cognition. At the same time, the scientific community did not find a single point of view on the possibility of applying the idea in practical science. It was only in 1988 that a conference was held in Venice, at which for the first time the main subject of consideration was the anthropic principle, and which attracted the attention of a very wide range of interested people - from physicists to religious philosophers. Thereafter this topic became the subject of discussion in numerous scientific forums, and one way or another, even at conferences on narrow scientific issues, the discussion touched on the question of what the anthropic principle states. Today, its application is extended to a very wide range of problems - from theology to extrapolar cosmology.
B. Carter in his famous article identified two variants of the manifestation of the principle - strong and weak. The weak version assumes that there are some constants which a person can observe only because he is present there. And vice versa: there are values of world constants that are different from what we are used to, where there is no observer (human) at the moment. Intuitive-everyday perception of this principle is somewhat expressed by the common saying: "it's good where we are not."
From the understanding of the strong version of the manifestation of the principle, the conclusion necessarily followed - the universe potentially has parameters that allow the mind to develop.
The anthropic principle in a strong manifestation was well formulated by J. Wheeler, arguing that "observers are necessary for gaining the Universe of being."
The difference between the strong and weak variants is that the strong characterizes the world at all stages of its existence, and the weak characterizes only those where the mind can only hypothetically originate.
The practical expression of the anthropic principle is the assumption that the reality we observe and its laws are not the only ones, and therefore there is a possibility of the existence of realities with other laws. At one time, the principle of anthropicity in this interpretation manifested itself at the discovery of non-Euclidean geometry, where the laws of classical do not apply. The manifestation of anthropicity can also be assumed in the situations described by Einstein: the dependence of the flow of time on speed.
Physicists who have studied options for the hypothetical existence in time and space of other Universes have come to the following conclusions:
In the course of constant changes that occur in the Universe, its parameters are also constantly changing, and therefore such a combination of these parameters may develop in which the appearance of intelligent life becomes inevitable;
The same can happen within the framework of one universe, in those places where its properties will be in a favorable ratio;
It is impossible to deny the hypothesis of the existence of some "multiverse" on the grounds that we do not observe it.
Thus, an attempt is made to expand the field by using the anthropic principle, taking it beyond the established laws of nature and the usual methodologies for their explanation.
The anthropic principle has received increasing attention in recent decades in a science such as cosmology, which is distinguished by its tendency to ask questions that go far beyond the science itself. The fundamental monograph by Barrow and Tipler recorded interest in such theories and was published in a number of leading biological, physical, philosophical, religious, theological and popular science publications. What is the reason for such increased attention?
Why is everything the way it is?
This is the first reason for the popularity of such a phenomenon as the anthropic principle in cosmology. Many see in it the answer to the eternal question: why is everything (nature in particular) arranged the way it is now, and not some other way? The Anthropic Principle states that the universe has all the properties that we observe by default. This happens for the reason that in another Universe with other properties of the observable there would be no observer himself, so simply no one could ask such questions about the structure of the universe. This leads to the conclusion that there is some "hidden principle" that organizes our Universe in a certain way. The anthropic principle is considered as the main attempt to explain the scientific-mysterious structure of the world.
Philosophical motive of cosmology
Is there a unity between man and nature (the universe)? The anthropic principle touches upon this eternal philosophical theme, and also asks the question of the nature of such a unity (if it exists). The answers to this question have always been diametrically opposed and often expressed in a paradoxical and shocking form. Many authors generally bypass the anthropic principle, and some even criticize and speak in a negative spirit.
Influence of Copernicus and Bruno
The anthropic principle, according to one of its authors, Carter, is based on a reaction against the blind excessive following of Copernicus. This scientist at one time argued that we should not believe that we occupy a central and privileged position in the world, without having good reasons for this. Strictly speaking, it would be more correct to call this principle after Giordano Bruno. Copernicus deprived the Earth of its right to a special position in the Universe, but endowed the Sun with such a status. A worldview based on the equivalence of all points and places in the world came to us from Bruno's ideas, for example, about the "plurality of universes." Copernicus expanded this ideological principle to a dogma, which is very doubtful and consists in the fact that our position is not a priori privileged. The anthropic cosmological principle considers this theory untenable, since the Universe develops and is not homogeneous in space, and also because favorable conditions are a direct prerequisite for our appearance (temperature, pressure, and so on). It follows that our position, although not privileged, is necessarily central. What is it? The anthropic principle of the Universe states that it is precisely the complex processes of organizing intelligent structures (of a person) that are nothing but a connection with the properties of the expansion and evolution of our Universe.
Development of the theory
The anthropic principle has a long ideological history, the origins of which are lost in the depths of history and culture. The idea of the unity of the Universe and man was developed in many religious and philosophical teachings. In the philosophy of the East, for example, this idea took the form of the "dissolution" of the individual in the surrounding world. In other directions, on the contrary, the principle of anthropocentrism was more popular (for example, in Aristotle) or the “pre-established harmony” of Leibniz. In the twentieth century, the problem of the unity of the universe and man began to attract the attention of scientists more and more. The anthropic principle was originally developed thanks to Wallace's research, in which one can find an attempt to revive teleology and anthropocentrism. Also, from his works, one can draw the most important moment and the main idea that a person is the crown of organic conscious life and could not develop just like that, by chance. Wallace wrote that a huge number of universes could well exist in infinite space.
Modern formation
The anthropic principle developed by leaps and bounds at the turn of the sixties. It was at this time that the macroscopic and microscopic structure of the Universe became clear, without understanding which it would be difficult to talk in detail about how man appeared and why. A connection was noted between the long and rapid expansion of the Universe and the conditions that allow the development of reason and civilization. A well-known astronomer like Idlis analyzed the problems concerning the origin of life from an astronomical point of view. It was concluded that the expansion of the Universe favors the evolutionary processes taking place in it, which ultimately led to the conclusion that we are not observing arbitrary regions of the Megagalaxy, but only those whose special structure has become suitable for the development and emergence of life in it. The anthropic cosmological principle undoubtedly absorbed all these conclusions.
Weak principle theory
The strong and weak anthropic principle are the fundamental and classical formulations derived by the scientist Carter in 1973, thanks to a controversy with his colleague Dicke. What it is? The weak principle says that our position in the Multiverse is privileged because it is consistent with our existence as direct observers. We are talking about explaining the isolation of the era in which intelligent beings live, the existence of which does not contradict the fundamental laws of nature, as well as the nature of evolution. The weak anthropic principle in cosmology states that if we lived in a different era, we would simply be absent in a series physical causes, which would not coincide and, as a result, could not be fixed. Thus, this fundamental law recognizes nature as a given and all its properties, stating our privileged position in the universe.
Strong principle theory
The strong anthropic principle states that the fundamental parameters of the universe must be such that observers can exist at a certain stage of evolution. The specificity of the Multiverse lies in a very fine "adjustment" of a number of numbers and physical constants in order to form and sustainably exist the basic elements of a highly organized world (nuclei, atoms, galaxies, stars, and so on). Even a minimal deviation would lead to a loss of stability and the loss of a link in evolution, which could be critical. The strong and weak anthropic principles are interconnected with each other; one cannot be considered in isolation from the other. With this approach, it can be argued that, since the "observer" exists, the Universe is a priori the way it is. Otherwise, there would be no one to observe it, and therefore it would not exist at all due to the absence of an observer and witness to its existence.
"Ensemble" of Universes
The anthropic principle in modern cosmology is associated with such a concept as the "ensemble" of the Universes. It postulates many variations of universes in which (as a result of scholastic processes) all combinations of parameters (both variables and fundamental constants) are realized without exception. The anthropic principle states that in this entire set there will be universes that have developed favorable circumstances for the birth of intelligent life at a certain stage of evolution. And our Universe just belongs to this type. Such a view of the anthropic principle in philosophy leads to a sound explanation of the effect of the finest "adjustment" of all parameters in our world and in space as a whole. Already in 1957, the physicist Everett developed his “many-worlds” concept in quantum mechanics, which states that at every moment of time there are and are realized all possible options development of the state of a particular system. The untropic principle in cosmology states that the physical Universe has an infinite number of so-called "branches" - copies of isolated worlds. At the same time, the observer can only be in one and does not know about the existence of other worlds. The stability of the Universe and the anthropic principle become much more understandable from a scientific and physical point of view if Everett's concept is applied to them.
Unique Universe
If the anthropic principle is correct, then there can be no self-selection, since nature does not have a “choice” as such. That is why theologians, religious scientists and philosophers became interested in this theory. The anthropic principle has many parallels with the "design argument": the subtle and complex "fitting" of all parts of the universe may well indicate the existence of some intelligent creator. The "principle of participation" developed not so long ago by the scientist J. Wheeler says that the observer is just as necessary for the emergence of the Universe, as well as vice versa. The universe exists through the presence of observations, which are carried out by intelligent beings at a certain stage of evolution.
Physical questions
But why did nature, out of all the possible array of solutions, choose exactly the one that led to the creation of us? Why were the initial conditions like this? According to the "anthropic statement", the theory of which appeared in the early eighties, there is a stage of "inflating" the Universe - its rapid expansion, inflation. At this time, there are processes of smoothing out any initial homogeneities and, as a consequence, the depreciation of these preconditions. The anthropic cosmological principle states that the current state of the Universe does not depend on the initial conditions and is an "attractor" for evolutionary trajectories. Thus, with the help of such a theory as the anthropic principle in cosmology, it became possible to describe the substrate parameters - the density of matter, the presence of spin elementary particles, the nature of the distribution of matter in the universe, and so on.
Carter identified two different formulations: weak AP and strong AP. Weak AP he formulated in this way: "Our position in the Universe is necessarily privileged in the sense that it must be compatible with our existence in the Universe." Strong AP says: "The universe (and, therefore, the fundamental parameters on which it depends) must be such that observers are allowed to exist in it at some stage of evolution." The difference between weak and strong AP is as follows. Weak AP is applied to parameters that depend on the present age of the Universe. Strong AP is applied to parameters that do not depend on age. When using weak AP, we are talking about the position of a person in the time scale. An example is the prediction of the relationship between Ho and atomic constants (section 4.3). As we have seen, in this case the AP leads to the relation
where To is the present age of the Universe.
The age of the Universe T is not its constant characteristic, it changes over time, it can be more or less. If the age is T Є Ts , the universe remains lifeless; if T є T , life in the Universe is also impossible. This means that the observer can exist only during the period of time when the age of the Universe is To ~ Ts . This imposes a constraint on the position of the observer in the timeline - a constraint that is a consequence of the natural laws of nature. There is no privilege for the observer here. It simply can appear only when the necessary conditions are ripe, and exists as long as the conditions allow its existence. Out of this context, the wording that our position is privileged (and necessarily privileged) gives reason to perceive it as a kind of tribute to anthropocentrism.
Since strong AP is applied to parameters that do not depend on the age of the Universe, it imposes a restriction not on the position of a person in time, but on the parameters inherent in the Universe itself. In this sense, the constraints are stronger, hence the name: strong AP. Since there is life and an observer in the Universe, the conditions must allow its existence, regardless of when and how it arises. For if they do not allow it, then the observer can never arise. For example, if the dimension of the physical space is N - 3, a person will not be able to exist in such a Universe, regardless of its age. In order for a person to appear in the Universe at some stage, it is necessary that N = 3. This is exactly what the strong AP claims.
Of course, if the above statements are understood literally, then it should be recognized that here cause and effect have changed places. In reality, the Universe is not like this, because a person exists in it, but a person exists in the Universe because exactly those conditions from the set of possible ones that turned out to be acceptable for the existence of life (and an observer) in it were realized in it. But since this has happened, and we exist, then the observable properties of the universe cannot be other than those required for life to become possible in it. Of course, one can judge the cause by the effect. But at the same time, one should not pass off the effect as the cause.
It is possible to formulate two extreme assumptions justifying the AP: 1) the mind in our Metagalaxy is an absolutely random phenomenon, which became possible only due to the unlikely but realized coincidence of many independent physical parameters; 2) the presence of biological and social forms motion is a natural consequence of the development of the Universe, and all its physical characteristics are interconnected and interdependent in such a way that they necessarily cause the appearance of intelligence.
The anthropic principle is the principle according to which all fundamental constants and the physical laws based on them are clearly defined, for the reason that only in such a Universe could an observer, that is, intelligent life, arise.
The question arises
With the development of science, scientists are increasingly observing the “feature” of our world, the physical laws of which are uniquely suited for the relatively stable existence of the Universe and the formation of intelligent life in it.
The fundamental world constants usually include the following parameters:
The values of these parameters are in a tiny range of values that allow the existence of intelligent life and the universe as a whole. Changing each of these constants would significantly change the laws of physics known to us, with disastrous consequences. Let's look at a few examples:
- If the masses of the protons participating in the strong interaction change, the strength of the interaction itself would also increase or decrease. In the first case, hydrogen could not form in the Universe, and the nuclei of many required for life chemical elements would fall apart. If the strong interaction were smaller, it would not be enough to form elements heavier than hydrogen.
- If the masses of the electrons participating in the weak interaction change, the weak interaction would also change. With a stronger weak force, much more helium would be produced in time, which would lead to excessive formation of heavy elements by stars. As a result, the impossibility of an explosion and the spread of formed heavy elements throughout the Universe, and hence the impossibility of the origin of life in a known form. If the weak force were much weaker, then the amount of helium would not be enough for a supernova explosion, which also does not allow the existence of life.
- By increasing the value of the gravitational constant, the stars would be hotter and less stable, which would not give enough time for the emergence of intelligent life. Otherwise, a small value of this parameter would lead to the formation of insufficiently hot stars and impossibility in them.
- Dimension of space. If we take into account the well-known law of universal gravitation, in a space with a greater dimension than three, planets would fall on the Sun, and electrons on the nucleus of an atom. In a two-dimensional space, however, massive bodies could not form a stable system bound by gravity, which is based on .
Also vital parameters are: the electromagnetic interaction constant, the level in the Universe, and even the half-life of beryllium-8, on which the formation of carbon and other chemical elements required for life depends.
All of the above facts indicate that the Universe is formed in such a way that intelligent life has a place to be in it. A large number of such coincidences became the foundation for the emergence of the so-called concept of "fine tuning of the Universe." The latter draws attention to the fact that the values of vitally important constants turn out to be precisely defined within the interval allowed for the formation of life. While the parameters that do not affect life so sharply can vary.
The Anthropic Principle and the Metaverse
The anthropic principle is designed to answer the question of the existence of a fine tuning of the Universe. There are two types of this principle:
- Weak. The Universe can conditionally be divided into regions, in each of which the fundamental constants have different values. However, we observe precisely such values, since only with such world constants could we be born as observers. Areas with other values of the parameters are hidden from observation for the reason that they do not allow the formation of life in them, that is, the observer.
- Strong. The Universe must have favorable conditions for the formation of intelligent life in it, since under other conditions it simply could not exist. A separate version of the strong principle is the so-called "anthropic principle of participation", according to which intelligent life is tightly connected with the existence of the Universe and is its integral part.
DNA is a complex structure that could not be formed under other conditions. Animated
The anthropic principle is based on the assumption that it can exist for some other values of the fundamental constants, that is, for other physical laws. Scientists have identified several options that fit the formulation of the anthropic principle:
- A single Universe, the parameters of the physical laws of which are constantly changing, in the course of its long or even infinite life. Under favorable conditions, that is, at certain values of physical constants, intelligent life is born - an observer.
- The Universe, which is divided into many independent and non-interacting regions, the physical parameters of which are different. In the area that satisfies the physical conditions sufficient for the origin of life, an observer appears.
- Multiverse. It refers to many other universes besides ours. They bear the name alternate universes or parallel worlds and have physical laws different from those known to us. Adherents of this version of the world order are such well-known scientists of our time as Stephen Hawking, Brian Green, Michio Kaku, Neil Tyson and others. The multiverse hypothesis is actively applied in the field.
- Universes of the anthropic principle of participation. That is, a number of Universes, perhaps with slightly different values of fundamental constants, which still include intelligent life.
Could it be that our existence is not a coincidence?
It is noteworthy that the anthropic principle contradicts the principle of Copernicus, who argued that the place where mankind originated and lives is not unique and special among a number of other places. A generalization of these two principles is the assertion that what is unique is not the place where humanity appeared or the values of fundamental constants, but the range of these values at which life has the right to exist.
The anthropic principle is one of the possible explanations for the mentioned fine tuning of the Universe. It seems impossible to verify the validity of this argument both now and in the future, since scientists will not be able to interact with other independent regions or universes, which means they will not be able to confirm their existence or disprove their existence.
In 1973, at the congress of scientists dedicated to the 500th anniversary of the birth of N. Copernicus, English physicist B. Carter put forward the so-called anthropic principle (AP), declaring the existence of a relationship between the parameters of the universe and the existence of mind in it. A formal impetus to the beginning of the discussion about the place of man in the universe was given by the discussion of the problem of coincidence big numbers– a strange numerical relationship between the parameters of the microcosm (Planck's constant, electron charge, nucleon size) and the global characteristics of the Metagalaxy (its mass, size, lifetime). This problem raised the question: how random are the parameters of our world, how interconnected are they, and what happens if they change slightly? An analysis of the possible variation of the main physical parameters showed that even their slight change leads to the impossibility of the existence of our Metagalaxy in an observable form and is incompatible with the appearance of life and intelligence in it.
The relationship between the parameters of the universe and the appearance of intelligence in it was expressed by Carter in two formulations - strong and weak.
“Weak AP” only states that the conditions existing in the Universe do not contradict the existence of man: “Our position in the Universe is necessarily privileged in the sense that it must be compatible with our existence as observers.”
“Strong AP” puts forward a more rigid relationship between the parameters of the Universe and the possibility and necessity of the appearance of intelligence in it: “The Universe must be such that the existence of observers is allowed in it at some stage of evolution.”
We can formulate two extreme assumptions justifying the AP:
1. Reason in our Metagalaxy is an absolutely random phenomenon, which became possible only due to the unlikely, but realized coincidence of many independent physical parameters
2. The presence of biological and social forms of movement is a natural consequence of the development of the Universe, and all its physical characteristics are interconnected and interdependent in such a way that they necessarily cause the appearance of intelligence.
To understand the Anthropic Principle, it is important to understand one essential circumstance: it was put forward without any connection with the problem of the existence of intelligent life or the study of the place of man in the Universe. Cosmologists and theoretical physicists involved in cosmology were interested in completely different problems: why does this or that cosmological parameter have a well-defined value? Why is the world arranged this way and not otherwise? Why is the universe the way we see it?
1. The dimension of the physical space "N". This is one of the most fundamental characteristics of our world. Why does space have three dimensions? Obviously, for "N<3» человек существовать не может. Возможно, что существуют двумерные и одномерные миры. Мы можем мысленно изучать их свойства, но наблюдать эти миры мы не можем. Остаются миры, в которых «N >= 3". What are the physical laws in these worlds? In our three-dimensional world for long-range interactions (which include gravitational and electromagnetic interactions), the interaction force of two point sources decreases inversely with the square of the distance between them - the law of universal gravitation and Coulomb's law. The expression for the force can be written as "F3 = a3/P3-1", where a3 is a proportionality factor that depends on the product of the interacting charges (or masses). Index 3 indicates that the formula is valid for three-dimensional space. This formula can be easily generalized to the case of an N-dimensional space:
"FN = aN/RN-1". An analysis of the nature of motion under the action of such a force (P. Ehrenfest, 1917) showed that for "N >= 4" in the two-body problem there are no closed stable orbits: the planet either falls on central body or goes to infinity. That is, in such worlds there are no analogues of planetary systems and atoms, and, consequently, life is impossible in them. Thus, the dimension of space turns out to be a vital factor. The only value of the "N" parameter that is compatible with the existence of life in the Universe is "N = 3". This, of course, does not explain why our world is three-dimensional, but it indicates why we observe such a world: in another world, we simply could not exist.
This applies not only to a person, but to any intelligent being (observer), which is a kind of complex structure built from atoms. Here it is not even necessary to be limited to consideration of the water-carbon form of life.
2. The average density of matter in the universe. In cosmology, there is the concept of critical density "pc". If the average density of matter in the Universe "p
The average density is related to the expansion rate of the Universe. If "r<
3.Coincidence of large numbers. There are several amazing relationships between the constants that characterize the universe. They even got the name "coincidence of large numbers." One of them relates the Hubble constant "H" to atomic constants. The question arises: how to explain this coincidence? Is it purely random or can it be predicted theoretically? It turns out that this is possible, but only for the inhabited Universe.
B. Carter formulated this position in the following way: it is possible theoretically (before observations) to predict “coincidences of large numbers”, if we use a certain Anthropological principle: what we can observe must be limited by the conditions necessary for our existence. In fact, in the previous examples, when referring to the habitable universe, we implicitly used this principle.
Let's see how it works in this example. In accordance with the anthropic principle, in the inhabited Universe, the relation Т0 ~ = ТS should be satisfied where Т0 is the modern age of the Universe (i.e., the age at the time of the existence of the observer), and ТS is the lifetime of stars. Indeed, if T0<<ТS, то к моменту Т0 в недрах звезд не успеют образоваться тяжелые элементы, необходимые для жизни. Если T0>>TS, then by this time all the nuclear fuel has already burned out, nuclear reactions in the interiors of stars will stop, and they will no longer supply the energy necessary for life. Therefore, the condition T0 ~ = ТS is necessary for the existence of life. And therefore it can be predicted that it should be fulfilled in our Universe.
Obviously, the structure of the Universe is extremely sensitive to the numerical values of these constants: it is preserved only within very narrow limits of their change. It is enough for the value of any of the constants to go beyond these narrow limits, as the structure of the Universe undergoes radical changes: it becomes impossible for the existence of one or more basic structural elements in it - atomic nuclei, the atoms themselves, stars or galaxies. In all these cases, life cannot exist in the Universe. Thus, the values of the fundamental constants determine the conditions necessary for the existence of life (and an observer) in the Universe. This is a rather unexpected result.
It means that in any habitable Universe (conceivable or actually existing) the fundamental physical constants cannot have other meanings than those known to us from experience. Therefore, using the Anthropic Principle, we can approximately predict the values of these constants without knowing anything about the results of their experimental determination.
These and similar examples exhaust the physical content of AP. Everything else is up to its interpretation. The attempt to move from prediction to explanation led to the development of the concept of an "ensemble of universes". The ensemble is characterized by all conceivable combinations of initial conditions and fundamental constants. In each universe of this ensemble, a certain set of parameters is realized. The existence of an observer is possible not for all, but only for some limited combinations of parameters that distinguish a cognizable subset in the ensemble of worlds. Obviously, our Universe belongs to this subset. You can also call it a subset of inhabited universes, and each universe of this subset is inhabited.
The ensemble of universes can be conceivable (“logically possible worlds” by G. Leibniz) or actually existing. At the same time, the worlds can be realized sequentially or exist in parallel. The ensemble of universes allows us to explain why we observe this or that property of the Universe. If this property is necessary for life, the answer might be: given property belongs to the typical properties inhabited universes, our universe is inhabited, so it also has this property.
