__________________________________________________________________________
SELECTED READINGS FOR ESSAY 3 (V)
SELECTED READINGS FOR ESSAY 3 (V)
__________________________________________________________________________
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Conclusions
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The first thing I have tried to show in this essay is that it is impossible to universally define what a beautiful theory is. In fact, twentieth-century physics illustrates that the idea of what is beautiful within physics and in a particular theory is subject to change. Some models have being raised in order to explain such changes. The philosopher of science James McAllister, refuting Thomas Kuhn, has proposed that ‘‘aesthetic criteria’’ of empirically successful theories tend to be appreciated as the norm of beauty. This process, dubbed ‘‘aesthetic induction’’ by McAllister, establishes the ‘‘aesthetic canon’’ employed for evaluating other empirically unverified theories.[source] In my opinion, instead, the beauty of a physical theory is not determined by the experimental success of such canonical theories. Let us take, for instance, electromagnetism. It is a theory that has been empirically confirmed an infinite number of times since its formulation, nevertheless, string theorists assess its beauty in a very precise sense: the unity of electricity and magnetism. (The same holds true for general relativity, quantum mechanics and particle physics.) But this interpretation, favoured by string theorists and other supporters of the unification program, is not always shared by physicists from other subdisciplines. In my view, what a group of physicists tend to see as beautiful in a specific theory and at a given time depends on certain manifest properties of the theory and on its position in the space of competing theories. Relying on this, practitioners will try to take advantage of present interpretations of well established theories as well as force new reinterpretations. The idea of this strategy is to maximise the chances of imposing their own explanatory model. In general, the evaluation is carried out on the basis of historical, theoretical, and sociological grounds.
*******You can read this blog for free! Please, do not copy its content.*******
From this perspective, if string theorists consider a particular theory to be beautiful it is because it is prevalently interpreted as containing the idea of unity (for example, the electroweak model). On the other hand, if current interpretations of a theory do not explicitly highlight its unifying aspect, string theorists will try to interpret it as such. For supporters of the unification program, the entire history of physics, or at least its main achievements, ought to be understood as a long march towards the beautiful unification of all the forces in a final theory. As Steven Weinberg puts it:
In short: in order to promote their own creation, string theorists have interpreted past theories in such a way as to stress the importance of unity.
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But, superstring theory has not been always thought to be a beautiful theory. In the third section I suggested that until the early nineties a crucial ingredient was missing: a propagandist Neo-Platonic discourse praising the mystical connection between the material world and our mathematical constructs. It was claimed that we were on the right track to the ultimate explanation of everything, ready to discover the fundamental equations in which God had written the elegant book of nature. Just to quote one final example, consider what John Barrow wrote in one of the most popular books on the theory of everything:
Under the pressure of this motivating ‘‘external’’ discourse, string theory became around the turn of the century a popular beautiful theory. This appreciation reached its apex of popularity during the first years of the twenty-first century; since then it has considerably waned.
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If the beauty of superstring theory can be understood as having concrete historical and sociological roots, why then do so many people talk about the “sense of beauty” in physics as something indescribable or too complicated to be conveyed to the non-expert? First of all, I must observe that the metaphysical discourse concerning physics and beauty is monopolized by the leaders, those who have been authorised by the community to write popular books and give public talks on the subject. These are the persons who are always interviewed by journalists working for scientific magazines and famous newspapers. In addition, this attitude has been promoted by an elitist approach to the history of physics. Poincaré, Einstein, Schrödinger, Dirac, Weinberg, Witten, and so on, these are the “Greats” who have grasped the beauty of nature and expressed it in beautiful equations. Even Thomas Kuhn once wrote: ‘‘Something must make at least a few scientists feel that the new proposal is on the right track, and sometimes it is only personal and inarticulate aesthetic considerations that can do that.’’[source] (Italics added.) This prejudice is reiterated again and again. But, after some experience within the field, I can assert that the anonymous string theorist, he or she who silently builds the beautiful edifice but never appears in the newspapers, does not know what is meant by mathematical beauty. The large majority of the members of the community (including junior and senior professors, postdocs, and graduate students), have never felt this unexplainable sensation that connects the ‘‘human mind’’ with the ‘‘glorious beauty’’ of nature. When they look for mathematical solutions to a particular problem, they are not guided by beauty, and, when they explain their results to other colleagues, beauty is never proposed as an argument. Hence, I think that if they publicly repeat this belief, it is simply because they have been educated within this hegemonic discourse and because the authority of the theory depends on it. The discourse on beauty has been important in two aspects: to attract new members to the field and to shield the theory from attacks coming from, but not limited to, the experimental tradition.
*******You can read this blog for free! Please, do not copy its content.*******
If I refuse the common idea that theoretical physicists may be effectively guided in their work by a ‘‘sense of beauty,’’ does it mean that I reject the significance of the assumption that the laws of nature are beautifully simple? Absolutely not! Contemporary physicists, including experimentalists, are persuaded that they are the inheritors of an old tradition begun in ancient times by Plato, or at least by Galileo almost four hundred years ago: “Sometimes in discussions among physicists, when it turns out that mathematical beautiful ideas are actually relevant to the real world, we get the feeling that there is something behind the blackboard, some deeper truth foreshadowing a final theory that makes our ideas turn out so well.”[source] That is, they believe that the fundamental laws of nature are written in mathematical characters and that their task is to discover them. Of course, this conviction is imprecise and from the historical point of view it is incorrect. Many theoretical physicists would be astonished to discover that the mathematization of natural phenomena was still a controversial issue during the nineteenth century and is only recently that it has become a common practice. However, the assumption has been very successful and modern physics stands on it. In conclusion, to Gabriele Veneziano’s question: “And what would happen if the simplicity of nature were a myth?” (“E se poi la semplicità della natura fosse un mito?”) I reply: of course it is a myth, but if you removed it the whole beautiful edifice of modern science would collapse.[source]
*******You can read this blog for free! Please, do not copy its content.*******
*******You can read this blog for free! Please, do not copy its content.*******
*******You can read this blog for free! Please, do not copy its content.*******
The first thing I have tried to show in this essay is that it is impossible to universally define what a beautiful theory is. In fact, twentieth-century physics illustrates that the idea of what is beautiful within physics and in a particular theory is subject to change. Some models have being raised in order to explain such changes. The philosopher of science James McAllister, refuting Thomas Kuhn, has proposed that ‘‘aesthetic criteria’’ of empirically successful theories tend to be appreciated as the norm of beauty. This process, dubbed ‘‘aesthetic induction’’ by McAllister, establishes the ‘‘aesthetic canon’’ employed for evaluating other empirically unverified theories.[source] In my opinion, instead, the beauty of a physical theory is not determined by the experimental success of such canonical theories. Let us take, for instance, electromagnetism. It is a theory that has been empirically confirmed an infinite number of times since its formulation, nevertheless, string theorists assess its beauty in a very precise sense: the unity of electricity and magnetism. (The same holds true for general relativity, quantum mechanics and particle physics.) But this interpretation, favoured by string theorists and other supporters of the unification program, is not always shared by physicists from other subdisciplines. In my view, what a group of physicists tend to see as beautiful in a specific theory and at a given time depends on certain manifest properties of the theory and on its position in the space of competing theories. Relying on this, practitioners will try to take advantage of present interpretations of well established theories as well as force new reinterpretations. The idea of this strategy is to maximise the chances of imposing their own explanatory model. In general, the evaluation is carried out on the basis of historical, theoretical, and sociological grounds.
*******You can read this blog for free! Please, do not copy its content.*******
From this perspective, if string theorists consider a particular theory to be beautiful it is because it is prevalently interpreted as containing the idea of unity (for example, the electroweak model). On the other hand, if current interpretations of a theory do not explicitly highlight its unifying aspect, string theorists will try to interpret it as such. For supporters of the unification program, the entire history of physics, or at least its main achievements, ought to be understood as a long march towards the beautiful unification of all the forces in a final theory. As Steven Weinberg puts it:
One of the primary goals of physics is to understand the wonderful variety of nature in a unified way. The greatest advances of the past have been steps toward this goal: the unification of terrestrial and celestial mechanics by Isaac Newton in the 17th century; of optics with the theories of electricity and magnetism by James Clerk Maxwell in the 19th century; of space-time geometry and the theory of gravitation by Albert Einstein in the years 1905 to 1916; and of chemistry and atomic physics through the advent of quantum mechanics in the 1920s.[source]*******You can read this blog for free! Please, do not copy its content.*******
In short: in order to promote their own creation, string theorists have interpreted past theories in such a way as to stress the importance of unity.
*******You can read this blog for free! Please, do not copy its content.*******
But, superstring theory has not been always thought to be a beautiful theory. In the third section I suggested that until the early nineties a crucial ingredient was missing: a propagandist Neo-Platonic discourse praising the mystical connection between the material world and our mathematical constructs. It was claimed that we were on the right track to the ultimate explanation of everything, ready to discover the fundamental equations in which God had written the elegant book of nature. Just to quote one final example, consider what John Barrow wrote in one of the most popular books on the theory of everything:
Our attraction to that quality which we have come to call “beauty,” and which we associate with the detection of innate unity and harmony in the face of superficial diversity, has led us to expect that the unity of the Universe should be expressed in certain particular ways.[source]*******You can read this blog for free! Please, do not copy its content.*******
Under the pressure of this motivating ‘‘external’’ discourse, string theory became around the turn of the century a popular beautiful theory. This appreciation reached its apex of popularity during the first years of the twenty-first century; since then it has considerably waned.
*******You can read this blog for free! Please, do not copy its content.*******
If the beauty of superstring theory can be understood as having concrete historical and sociological roots, why then do so many people talk about the “sense of beauty” in physics as something indescribable or too complicated to be conveyed to the non-expert? First of all, I must observe that the metaphysical discourse concerning physics and beauty is monopolized by the leaders, those who have been authorised by the community to write popular books and give public talks on the subject. These are the persons who are always interviewed by journalists working for scientific magazines and famous newspapers. In addition, this attitude has been promoted by an elitist approach to the history of physics. Poincaré, Einstein, Schrödinger, Dirac, Weinberg, Witten, and so on, these are the “Greats” who have grasped the beauty of nature and expressed it in beautiful equations. Even Thomas Kuhn once wrote: ‘‘Something must make at least a few scientists feel that the new proposal is on the right track, and sometimes it is only personal and inarticulate aesthetic considerations that can do that.’’[source] (Italics added.) This prejudice is reiterated again and again. But, after some experience within the field, I can assert that the anonymous string theorist, he or she who silently builds the beautiful edifice but never appears in the newspapers, does not know what is meant by mathematical beauty. The large majority of the members of the community (including junior and senior professors, postdocs, and graduate students), have never felt this unexplainable sensation that connects the ‘‘human mind’’ with the ‘‘glorious beauty’’ of nature. When they look for mathematical solutions to a particular problem, they are not guided by beauty, and, when they explain their results to other colleagues, beauty is never proposed as an argument. Hence, I think that if they publicly repeat this belief, it is simply because they have been educated within this hegemonic discourse and because the authority of the theory depends on it. The discourse on beauty has been important in two aspects: to attract new members to the field and to shield the theory from attacks coming from, but not limited to, the experimental tradition.
*******You can read this blog for free! Please, do not copy its content.*******
If I refuse the common idea that theoretical physicists may be effectively guided in their work by a ‘‘sense of beauty,’’ does it mean that I reject the significance of the assumption that the laws of nature are beautifully simple? Absolutely not! Contemporary physicists, including experimentalists, are persuaded that they are the inheritors of an old tradition begun in ancient times by Plato, or at least by Galileo almost four hundred years ago: “Sometimes in discussions among physicists, when it turns out that mathematical beautiful ideas are actually relevant to the real world, we get the feeling that there is something behind the blackboard, some deeper truth foreshadowing a final theory that makes our ideas turn out so well.”[source] That is, they believe that the fundamental laws of nature are written in mathematical characters and that their task is to discover them. Of course, this conviction is imprecise and from the historical point of view it is incorrect. Many theoretical physicists would be astonished to discover that the mathematization of natural phenomena was still a controversial issue during the nineteenth century and is only recently that it has become a common practice. However, the assumption has been very successful and modern physics stands on it. In conclusion, to Gabriele Veneziano’s question: “And what would happen if the simplicity of nature were a myth?” (“E se poi la semplicità della natura fosse un mito?”) I reply: of course it is a myth, but if you removed it the whole beautiful edifice of modern science would collapse.[source]
*******You can read this blog for free! Please, do not copy its content.*******
__________________________________________________________________________
SELECTED READINGS FOR ESSAY 3 (V)
SELECTED READINGS FOR ESSAY 3 (V)
__________________________________________________________________________
*******You can read this blog for free! Please, do not copy its content.**************You can read this blog for free! Please, do not copy its content.*******
