Physics 203 H' Padamsee

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Physics 203H. Padamsee
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Why should we study Physics?

• Our culture values science for its stream of
  inventions, for the improvement of human life.
• -Examples?
• Television, Computers, CD players, Cell phones
• But science is not only important to us for its
  technological consequences.
• It brings us great intellectual satisfaction.
• Science opens new vistas.
• The universe is immense, full of galaxies, like
  our Milky Way,
• Stars like our Sun, and planets like our Earth
• We are intrigued by questions

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Examples

• What is our world made of?
• What are stars made of?
• What is the universe made of?
• Where did the earth, moon, sun and stars come
  from?
• What is the origin of the universe?

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• What is our place in the universe?
• Are there other worlds like our own?
• Are there life forms other than our own?
• Is there intelligent life out there?
• Can you think of others?

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When we expand our thinking to the universe and
our place in it, we wonder

• What brings about the incessant changes?
• Can we understand the workings of the universe?
• Is Nature governed by natural laws, rather than
  by divine command?
• Can we hope to fathom those laws?
• Such questions lie at the very heart of
  scientific thought

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• We will explore the first arena of science
  which
• emerged to show that
• -The Universe is indeed fundamentally
  orderly.
• -Nature is governed by natural laws.
• William Shakespeare proclaims in Troilus and
  Cressida
• The heavens themselves,
• The planets and this center,
• Observe degree, priority, and place,
• Insisture, course, proportion, season, form,
• Office, and custom, in all line of order.

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• This was the ultimate triumph of Newtonian
  mechanics.
• Newton penetrated the laws of motion in the
  universe
• on the earth and in the heavens. e.g.
• how and why does an apple fall from the tree to
  the ground?
• what is the cause of the regular tides?
• how and why does the moon go around the earth?
• how and why does the earth go around the sun?

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Before Newton

• It was generally thought that the laws which
  operate in the heavens are different from the
  laws that operate on the earth.
• Our literature and our art reflect the belief
  that
• God separated Heaven and Earth at Creation.

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• And God said let there be a firmament in the
  midst of the waters, and let it divide the waters
  from the waters. And God made the firmament, and
  divided the waters which were under the firmament
  from the waters which were above the firmament.
  
• 
  -Genesis

Von Carolsfeld
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Newtonian mechanics was the FIRST SYNTHESIS

• Between two distinct areas
• Astronomy and Dynamics (physics of motion)
• He successfully explained,
• and in quantitative detail
• The motions of the heavenly bodies
• the sun, the moon, the planets, the comets and
  the stars.
• What was truly wonderful was that with these same
  laws he could explain motion on earth,
• e.g. the free fall of the legendary apple,
• the rise and fall of the tides.

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• Poet Alexander Pope captured the overwhelming
  impact of Newtons accomplishments
• Nature and Natures laws lay hid in the night
• God said, Let Newton be! And all was light.

Newton By William Blake
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• Newtons success generated intellectual optimism
  as never experienced before.
• -The universe is fundamentally orderly,
• Nature is governed by laws.
• -The same laws that operate on Earth operate
• everywhere in the universe.
• He forged confidence in the power of reason.
• -The human mind is capable of discovering those
  laws.
• -Our intellect is capable of understanding all
  natural
• phenomena.

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• Newtons mechanics and approach became the
  prototype of the method for future scientific
  inquiry
• -The model to emulate throughout the
  development of science.
• -Science rose to one of the principal
  activities of society.
• -Science was accepted as a force in the
• advancement of civilization.
• I want to know how God created this world. I am
  not interested in this or that phenomenon. I
  want to know His thoughts, the rest are details
  Einstein

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• Newton himself was more modest about his
  accomplishment!
• One of his most remarkable statements was
• If I have seen further than other men,
• it is because I stood on the shoulders of
  giants.
• Who were these giants?
• Galileo, Kepler, Brahe
• Ptolemy, Hipparchus, Apollonius
• Aristarchus, Archimedes, Euclid
• Aristotle , Plato, Pythagoras, Thales..

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• Threads of this course
• What did they discover? How did they do it?
• To appreciate Newtons accomplishments we must
  understand of how he and his predecessors reached
  the insights.
• In doing so we will appreciate and understand not
  only of mechanics but all of physics, and indeed
  all scientific thought.

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Plan for Course Topics
5 Heaven 6 Motion in the Heavens 7. Revolution
1. Earth 2. Elements in Motion 3. Rise of
Empiricism
8. Laws of Motion in the Heavens
4. Laws of Motion on Earth
9. A new Heaven
10. A New earth
10. Rise of the Mechanical Universe
11. Synthesis

Universal Gravitation - Consequences
12. Unity of Physics
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Plan for Course Topics
Earth, Elements
The Greek Universe
Chaps 1
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Old and New Periodic Tables of Elements
Chap 2
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Transition from Greek to Renaissance
Chap 3
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Galileo Motion on Earth
Horizontal Motion
Free Fall
Chap 4
Including simple numerical aspects Appendix 1
Parabolic Motion
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Plan for Course Topics
5 Heaven 6 Motion in the Heavens 7. Revolution
1. Earth 2. Elements in Motion 3. Rise of
Empiricism
8. Laws of Motion in the Heavens
4. Laws of Motion on Earth
9. A new Heaven
10. A New earth
10. Rise of the Mechanical Universe
11. Synthesis

Universal Gravitation - Consequences
12. Unity of Physics
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Heavens

• Motion in the heavens, Chap 5
• Modelling the heavens, Chap 6

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Laws of Heavenly Motion

• Copernican Revolution, Chap 7
• Keplers Laws, Chap 8

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A New Heaven
Chap 9
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Plan for Course Topics
5 Heaven 6 Motion in the Heavens 7. Revolution
1. Earth 2. Elements in Motion 3. Rise of
Empiricism
8. Laws of Motion in the Heavens
4. Laws of Motion on Earth
9. A new Heaven
10. A New earth
10. Rise of the Mechanical Universe
11. Synthesis

Universal Gravitation - Consequences
12. Unity of Physics
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A New Earth

• Circumnavigating the globe
• Latitude and longitude
• Precision in time-reckoning
• Linkage of space and time

Chap 10
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Rise of the Mechanical Universe

• The clockwork universe
• What is the mechanism that runs the universe?

Chap 10
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Universal GravitationNewtonian Synthesisof
Celestial and Terrestrial Motion
Including simple numerical aspects
Chap 11
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Modern Physics Updates

• Einsteins theories of relativity and
• The meaning of gravity

Chap 11- 12
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• Frequent Connections to
• Modern Physics Topics

Examples Chemical Elements, Atoms, Nucleus New
Elements Quarks, Leptons Expanding Universe The
Big Bang
View the exciting ideas of modern physics in the
context of the grand traditions they continue.
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• Demonstration Experiments
• Examples
• Inertia
• Gravity

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• View Physics from Multiple Perspectives
• - Evolutionary Perspective
• Not just the laws and the science but also
• -How do we know?
• -how did a particular scientist discover a
  law
• - Human perspective
• Stories of breakthroughs and brilliants insights
  by fascinating people
• -stories about the scientists too
• - Cultural perspective
• The scientists lived in interesting times,
• their theories developed within a cultural
  back-drop
• Connections to art and poetry

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• Why should we discuss art in a course about
  science?
• Both science and art express a desire to see
  beyond the seen
• They both share in the careful observation of
  things,
• and reflections about their nature.
• Example Symmetry and Broken Symmetry

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Like Art, Science is a Creative Activity

• We are guided by certain aesthetic principles
• -Simplicity
• -Beauty
• -Order
• -Unity
• Nature is governed by simple laws
• If there are two explanations,
• we are attracted to the simpler one
• the one which involves
• fewer effects, fewer assumptions.
• The epic poet Dante Alighieri wrote in the 14th
  century
• All that is superfluous displeases God and
  nature. All that displeases God and nature is
  evil.

Nature is pleased with simplicity, and affects
not the pomp of superfluous causes Isaac Newton.
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Nature is Beautiful

• The modern physicist Herman Weyl declared
• My work always tired to unite the true with the
  beautiful, but when I had to chose one or the
  other, I usually chose the beautiful.

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Theories of Nature must be Elegant
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Order, Symmetry and Mathematics in the Operations
of Nature
Section topics for tomorrow !

• Mathematics helps us to express that order
• We can see more with mathematics than we can see
  with words and thoughts
• Emphasis simple numerical aspects, we will teach

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How can it be that mathematics, a product of
human thought independent of experience, is so
admirably adapted to the objects of reality?
Einstein There is no branch of mathematics
however abstract which may not someday be applied
to the phenomena of the real world
Lobachevsky..(one of the inventor of
non- Euclidean geometry) The mathematician does
not study pure mathematics because it is useful
he studies it because he delights in it, and he
delights in it because it is beautiful. 1-1/3
1/5- 1/7 1/9 - 1/11 p/4 !
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• There is Unity Underlying the Apparent Diversity.
• Is there one fundamental substance out of which
  the universe is made?

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Different areas of science are always coming
together

• Heaven and Earth
• The laws that govern the motion of heavenly
• bodies are the same as those that govern the
• motion of earthly objects
• (Main topic of this course)

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Unity

• The unification of distinct areas of physics
  leads to an explosion in the growth of knowledge
  and understanding

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• Is there a grand unifying theory that explains
  all physical phenomena?

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New Ways of Looking at the World
Crossing Boundaries Physics Art
No great artist sees things as they really are.
If he did, he would cease to be an artist.
Oscar Wilde
Rene Magritte
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All themes recur throughout the course
My aim in this course is to show The most
beautiful thing we can experience is the
mysterious. It is the source of all true art and
science. He to whom this emotion is a stranger,
who can no longer pause to wonder and stand
wrapped in awe, is as good as dead. - Albert
Einstein

• -Look for the recurring themes
• Recognize them.
• Think about them.
• Write about them.
• -Questions about content?

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Paper must be written according to guidelines
issued.
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Sample Question, Only for System Try OutP203
relates to various cultures. Where have you
travelled?

• A. Greece
• B. Egypt
• C. Italy
• D. England

Note This question does not test P203 knowledge,
we will do that next time. First Quiz is a
freebie.. Please make sure you have you H-ITT
Clicker ! Write down your name and clicker number
and give it to your TA. Your grade depends on it
!
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