Truth, Beauty and the Meaning of Understanding Nature

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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 1010 meters Elementary particle
phenomena about 1018 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
(15th16th centur-ies), Johannes Kepler, Galileo
Galilei (16th17th centuries) Isaac Newton
(16421727) Natures of space and time, laws of
motion, universal gravitation GalileanNewtonian
world view Controlled experiments, mathematical
description and analysis 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
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It required a severe struggle (for Newton) to
arrive at the concept of independent and absolute
space, indispensable for the development of
theory. Newtons 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 GalileanNewtonian
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 com-munication 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
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