Truth, Beauty and the Meaning of Understanding Nature
Philosophical traditions (India, Greece) – about 2000 years old
Modern Science – about 400 years old
Scales of the Universe
Number of galaxies – about one hundred billion, 1011
Number of stars in a galaxy – about 1011
Age of the Universe – almost 15 billion years
Age of the solar system – about 4½ billion years
Light travel times:
• from Sun to Earth – about 8 minutes
• across the Solar system – about 5½ hours
• across the Milky Way – about 80,000 years
• across the Universe – about 10 billion years
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Radius of the Universe – about 1026 meters
Sizes of atoms – about 10–10 meters
Elementary particle phenomena – about 10–18 meters
Our place in the Universe
Life on earth – about 4 billion years old
Hominids appeared – 3 to 5 million years ago
Homo sapiens sapiens – about 1,00,000 years ago
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Beginnings of Greek Science
Thales of Miletus, 6th century BC
“…a new commonsense way of looking at the world of things…
the whole point of which is that it gathers together into a coherent
picture a number of observed facts without letting Marduk (the
Babylonian Creator) in….”
— Benjamin Farrington
“…the strongest impulse had come from the immediate reality of
the world in which we live and which we perceive by our senses.
This reality was full of life and there was no good reason to stress
the distinction between matter and mind or between body and
soul.”
— Werner Heisenberg
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Greek traditions, Schools
Anaximander, Pythagoras, Leucippus, Democritus, Plato, Aristotle,
Euclid…
Rationalism
Pythagoras, Plato, Aristotle… Rene Descartes, Wilhelm Leibnitz, Benedict
de Spinoza…
“…knowledge of Nature does not require observation and is attainable
through reason alone.”
— Plato
Centuries later, on Aristotle:
“He did not consult experience as he should have done, but having first
determined the question according to his will, he then resorted to experience
and led her about like a captive in a procession.”
— Francis Bacon
Empiricism
Thales, Democritus… Francis Bacon, John Locke, Bishop Berkeley, David
Hume…
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Beginnings of Modern Science
Nicolas Copernicus (15th–16th centur-ies), Johannes Kepler, Galileo
Galilei (16th–17th centuries)
Isaac Newton (1642–1727): Natures of space and time, laws of
motion, universal gravitation
Galilean–Newtonian world view:
mathematical description and analysis
Controlled
experiments,
“The distinctive quality of these great thinkers was their ability to
free themselves from the metaphysical traditions of their time and to
express the results of observations and experiments in a new
mathematical language regardless of any philosophical
preconceptions.”
— Max Born
5
“It required a severe struggle (for Newton) to arrive at the concept
of independent and absolute space, indispensable for the
development of theory. Newton’s decision was, in the contemporary
state of science, the only possible one, and particularly the only
fruitful one…. It has required no less strenuous exertions
subsequently to overcome this concept (of absolute space).”
— Albert Einstein
After Newton – over 18th century – progress in astronomy or
celestial mechanics, fluid dynamics, elastic media,…, static
electricity and magnetism.
Leonard Euler, Joseph Louis Lagrange, Pierre Simon de Laplace,
Charles Augustin de Coulomb
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End of 18th century, attempt by Immanuel Kant to explain the
success of Galilean–Newtonian approach
Knowledge of Nature – two components – the a priori, in advance
of experience; the a posteriori, the result of experience
Absolute space and time, Euclidean geometry, law of causality,
permanence of matter, conservation of mass – a priori principles
“…one is very easily deceived into regarding an acquired habit of
thought as a peremptory postulate imposed by our mind on any
theory of the physical world.”
— Erwin Schrödinger
Progress in physics beyond Kantian framework – ideas of space and
time, interactions among bodies, nature of geometry, permanence of
matter, conservation of mass…
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Input from evolutionary biology – Konrad Lorenz, Max Delbruck
Relationship between biological species as a whole, and individual
members of the species
Learning by species – phylogenetic learning versus learning by
individual – ontogenetic learning
Species learning – slow, guided by natural selection, retention of
abilities to recognize important physical features of world around us
at our scales of length and time
These abilities given ready made at birth to individual – seem a
priori
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“It appears therefore that two kinds of learning are involved in our
dealing with the world. One is phylogenetic learning, in the sense
that during evolution we have evolved very sophisticated
machinery for perceiving and making inferences about a real
world… whereas in the light of modern understanding of
evolutionary processes, we can say the individual approaches
perception a priori, this is by no means true when we consider the
history of mankind as a whole. What is a priori for individuals is a
posteriori for the species. The second kind of learning involved in
dealing with the world is ontogenetic learning, namely the lifelong
acquisition of cultural, linguistic and scientific knowledge.”
— Max Delbruck
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Scientific knowledge, understanding of Nature
Our senses fashioned over millions of years by evolution, in contact
with World of Middle Dimensions. Each sense limited. All
knowledge ultimately subjective. Through intellect and communication we seek objectivity.
Charming exchange – the intellect says:
“Ostensibly there is colour, ostensibly sweetness, ostensibly
bitterness, actually only atoms and the void.”
The senses retort:
“Poor intellect, do you hope to defeat us while from us you borrow
your evidence? Your victory is your defeat.”
— Schrödinger quoting from Democritus
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Nature of Science
“Nature is earlier than man, but man is earlier than
natural science”
— Heisenberg quoting von Weiszacker
“We know nothing of reality, for truth lies in an abyss”
— Democritus
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Relevance of Beauty
Use of mathematics in physical science
“Beauty in things exists in the mind which contemplates them”
— David Hume
“My work always tried to unite the true with the beautiful, but
when I had to choose one or the other, I usually chose the
beautiful”
— Hermann Weyl
“Mathematical beauty cannot be defined any more than beauty in
art can be defined, but which people who study mathematics
usually have no difficulty in appreciating”
— Paul Dirac
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Emotions upon the discovery of quantum mechanics –
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“I had the feeling that, through the surface of atomic phenomena, I
was looking at a strangely beautiful interior, and felt almost giddy
at the thought that I now had to probe this wealth of mathematical
structure nature had so generously spread out before me”
— Heisenberg
“The soul is awestricken and shudders at the sight of the beautiful,
for it feels that something is evoked in it that was not imparted to
it from without by the senses, but has always been already laid
down there in the deeply unconscious region”
— Plato, in ‘The Phaedrus’
A concluding thought
“What the imagination seizes as beauty must be truth – whether it
existed before or not”
— John Keats