Big Questions in Science series, (2 of 9). Class taught at AUC (University of Amsterdam) during the 2012-2013 fall semester.

1. Physics, Astronomy, Chemistry
Sebastian de Haro, fall 2012

2. 4a Our cosmic origins
3a, 3b Time and relativity
4b, 5a Quantum mechanics
5b Chemistry
1b Classical physics
Big Questions in Science, spring 2012. SdH, AUC
fall 2012. SdH, AUC 2

3.  Class discussion:
 List some of the essential properties of science as
an academic activity (also properties that
distinguish it from other activities).
Big Questions in Science, fall 2012. SdH, AUC 3

4.  The following elements will have appeared in
your definitions of science discussed in class:
 Logic, rigor.
 Scientific method.
 Falsifiability .
 Experimental verifiability.
Big Questions in Science, fall 2012. SdH, AUC 4

5.  One goal of the course is to demystify some of the
ideas about science that you may find in popular
books or media:
 Science is messy, with lots of guesswork, serendipity.
 Theories are not falsified by one single observation.
 Scientific products are presented in the strictly logical,
rigorous way. But the actual scientific process
(including research and scientific discussions) is
usually rather different.
Big Questions in Science, fall 2012. SdH, AUC 5

6.  Four generic properties I would like to emphasize, in
addition to the ones already mentioned:
Big Questions in Science, fall 2012. SdH, AUC 6

7. Key driving force behind scientific research:
human curiosity. We want to know what
nature around us looks like, both in the
worlds of the smallest, of the largest, and in
the intermediate scale of complexity.
Other important driving forces:
http://inhabitat.com/new-mars-curiosity-science-laboratory-will-be-nuclear-powered-not-solar-powered/
economic interests, technological
http://outreach.atnf.csiro.au/
advance, societal and political needs,…
Big Questions in Science, fall 2012. SdH, AUC
http://ebooks.adelaide.edu.au/h/hooke/robert/micrographia/plates/scheme34.png
7
http://www.umsl.edu/~fraundorfp/stm97x.html

8. If artists represent (or interpret) aspects of reality that usually cannot be grasped by
analytic means, scientists aim to represent its objective, quantitative features. Both
artists and scientists need lots of creativity!
The scientific enterprise requires abstraction from reality: retaining the aspects that
are relevant to a particular question or research, searching for universal patterns,
laws, and principles that can be reproduced and tested.
Big Questions in Science, fall 2012. SdH, AUC 8
http://en.wikipedia.org/wiki/Las_Meninas http://www.blogmuseupicassobcn.org/2009/06/weve-got-something-special-to-celebrate-a-brand-new-addition-to-the-museu-picasso/?lang=en

9. http://science.nasa.gov/science-news/science-at-nasa/2004/13jul_solarblast/
Experiment and observation. Experiments allow scientists
to test their hypotheses or gather new information about
nature in a controlled setting. Changing the experimental
conditions allows to establish or disprove causal links.
Big Questions in Science, fall 2012. SdH, AUC 9

10. Science and philosophy: “Traditionally these are questions for philosophy,
a love-hate relationship but philosophy is dead. Philosophy has not
kept up with modern developments in
science, particularly physics. Scientists have
become the bearers of the torch of discovery
in our quest for knowledge. The purpose of
this book is to give the answers that are
suggested by recent discoveries and theoretical
advances. They lead us to a new picture of the
universe and our place in it that is very different
from the traditional one, and different even from
the picture we might have painted just a decade
or two ago. Still, the first sketches of the new
concept can be traced back almost a century.”
(The Grand Design).
Big Questions in Science, fall 2012. SdH, AUC 10

11. Big Questions in Science, fall 2012. SdH, AUC 11

12. Big Questions in Science, fall 2012. SdH, AUC 12

13.  Method does not guarantee full truth or even
empirical adequacy.
 Dogmatism about ‘method’ can kill creativity:
 Rutehrford wouldn’t let Bohr publish his result.
 Bohr wouldn’t Heisenberg publish his result.
 Heisenberg said the Higgs was not the way the
world works.
 Methodologies change.
 Look at actual examples!
Big Questions in Science, fall 2012. SdH, AUC 13

14. Technology
Future reality
Model
Presuppositions
Experiment
Axioms
Mathematics Reality
Logic
Presuppositions (ethical,
Observation
epistemic, ontological)
• Science aims at representing reality in a model that allows to Past reality
explain the present and predict the future (retrodict or understand
the past). Technology, experiment, and observation play an
important role in connecting models with reality.
• The model itself rests on experimental data, a number of specific
axioms, as well as a broader set of assumptions. The particular
logic employed depends on the particular field. Big Questions in Science, fall 2012. SdH, AUC 14

15. A brief history of the universe
Turning points in the
history of the universe
organized around the
universe’s timeline.
Main era’s in the
evolution of the
universe.
http://planck.cf.ac.uk/science/timeline/universe Big Questions in Science, fall 2012. SdH, AUC 15

16.  Documentary film Powers of Ten (9 min)
Big Questions in Science, fall 2012. SdH, AUC 16

17.  In groups of two: go to http://htwins.net/scale2
and look up, for ten different length scales
( , etc.), ten corresponding items in
the universe. Go also to the negative powers!
Pay particular attention to earth science &
biology.
 Switch off the sound!
 We will make a (linear) map of the universe.
 You can cross-check your data with estimates
that you find on the internet.
Big Questions in Science, fall 2012. SdH, AUC 17

18. Metric prefixes
Prefix Symbol 1000m 10n Decimal Short scale Long scale Since[n 1]
1000000000000000
yotta Y 10008 1024 septillion quadrillion 1991
000000000
1000000000000000
zetta Z 10007 1021 sextillion trilliard 1991
000000
1000000000000000
exa E 10006 1018 quintillion trillion 1975
000
peta P 10005 1015 1000000000000000 quadrillion billiard 1975
tera T 10004 1012 1000000000000 trillion billion 1960
giga G 10003 109 1000000000 billion milliard 1960
mega M 10002 106 1000000 million 1960
kilo k 10001 103 1000 thousand 1795
hecto h 10002/3 102 100 hundred 1795
deca da 10001/3 101 10 ten 1795
10000 100 1 one –
deci d 1000−1/3 10−1 0.1 tenth 1795
centi c 1000−2/3 10−2 0.01 hundredth 1795
milli m 1000−1 10−3 0.001 thousandth 1795
micro μ 1000−2 10−6 0.000001 millionth 1960
nano n 1000−3 10−9 0.000000001 billionth milliardth 1960
pico p 1000−4 10−12 0.000000000001 trillionth billionth 1960
femto f 1000−5 10−15 0.000000000000001 quadrillionth billiardth 1964
0.000000000000000
atto a 1000−6 10−18 quintillionth trillionth 1964
001
0.000000000000000
zepto z 1000−7 10−21 sextillionth trilliardth 1991
000001
0.000000000000000
yocto y 1000−8 10−24 septillionth quadrillionth 1991
000000001
Big Questions in Science, fall 2012. SdH, AUC 18

19. The Big Questions Connecting Circle
Big Questions in Science, fall 2012. SdH, AUC 19

20. Different length scales
distributed on the Big
Questions Connecting
Circle. Big Questions in Science, fall 2012. SdH, AUC 20

21. Examples of scientific theories distributed on
the Big Questions Connecting Circle. Big Questions in Science, fall 2012. SdH, AUC 21

22. Examples of sciences distributed on the
Big Questions Connecting Circle. Big Questions in Science, fall 2012. SdH, AUC 22

23.  Presocratic science: study of matter and
astronomy
 Atomism and Plato’s Timaeus: mathematics
 Greek science: First Theories of Everything
Big Questions in Science, fall 2012. SdH, AUC 23

24. Thales: water, predicted solar eclipse.
Anaximander: apeiron,
Earth cylindrical, suspended in void.
Anaximenes: air (rarefaction,
condensation).
Heraclitus: fire
Empedocles: four elements
Democritus and Leucippus: atoms,
Flat earth.
Big Questions in Science, fall 2012. SdH, AUC 24

25. 585 BC Thales
of Miletus
Big Questions in Science, fall 2012. SdH, AUC 25

26.  Time and length scales
 Great adventure: curiosity
 Abstraction
 Methods:question, observation, knowledge,
innovation
 From mythos to logos
 Greek science: matter, geometry.
Big Questions in Science, fall 2012. SdH, AUC 26

27.  Theaetetus via Plato and Euclides: the five
Platonic solids
Big Questions in Science, fall 2012. SdH, AUC 27

28. Tetrahedron, octahedron, icosahedron
Cube (rectangle)
(equilateral triangles)
Set minimal length to 1.
No ! Use Pythagoras theorem other lengths follow
Big Questions in Science, fall 2012. SdH, AUC 28

29.  The numbers (1,2,3) are given by musical
octave and fifth. Generate the Dorian musical
scale:
1:2 octave 6 89 12
2:3 perfect fifth 1 2
D E F# G A B C# D
3:4 perfect fourth
4:5 major third 4/3 harmonic mean
5:6 minor third
3/2 arithmetic mean
Big Questions in Science, fall 2012. SdH, AUC 29

30.  Properties of elementary triangles linked with
harmonies of music.
 Platonic solids built up of such triangles.
Properties of triangles give properties of
solids and will ‘explain’ properties of matter.
Big Questions in Science, fall 2012. SdH, AUC 30

31. Earth Fire Air Water
Symmetry among
these three: all share
same elementary
triangles
Big Questions in Science, fall 2012. SdH, AUC 31

32. Earth Fire Air Water
condensation
rarification, condensation evaporation
Big Questions in Science, fall 2012. SdH, AUC 32

33. Big Questions in Science, fall 2012. SdH, AUC 33

34.  Largest volume when inscribed in sphere.
 Contains other Platonic solids.
Big Questions in Science, fall 2012. SdH, AUC 34

35.  Numbers as universal language, at the root of
all natural processes.
 Symmetry leads to ‘conserved quantities’:
 Stable earth: isosceles triangle symmetric.
 Interchangeability fire, air, water.
 Link between numbers, physiology, and arts:
quantity and quality.
 Adds concept of ‘measure’, ‘form’ to
Ionian/atomistic ideas.
Big Questions in Science, fall 2012. SdH, AUC 35

36.  Although speculative, basic principle is a
chemistry of four elements.
 Reactions explained from mathematical
combinations allowed by geometry.
 Problem of ‘asymmetry’ always present:
‘likely account’. Hypothesis open to critique.
Big Questions in Science, fall 2012. SdH, AUC 36

37.  “Our illustrator of the atomic model [in a
school text-book of physics] would have done
well to make a careful study of Plato before
producing his particular illustration”
(Heisenberg, cited by Guthrie).
 Heisenberg first thought about atoms while
reading Plato’s Timaeus.
 Pythagoras highly influential at dawn of two
scientific revolutions: Kepler and
Sommerfeld.
Big Questions in Science, fall 2012. SdH, AUC 37

38.  Rational explanation
 Logic, argumentation
 Empirical (though not ‘experimental’)
 Universe finite and knowable
 Important factors:
 Development of culture
 Overseas trading, different civilizations
 Openness to intellectual innovation
Big Questions in Science, fall 2012. SdH, AUC 38

39. Periodic table: classification scheme of the chemical elements based on simple physical principles.
Big Questions in Science, fall 2012. SdH, AUC 39

40. Physical forces: seemingly distinct forces can be reduced to simpler forces and mathematical principles.
Big Questions in Science, fall 2012. SdH, AUC 40