and Atoms Stars IST 2420 and IST 1990
Class 2 Winter 2006 Instructor: David Bowen
Course web site: www.is.wayne.edu/drbowen/aasw06 IST 1990 Moodle: techtools.culma.wayne.edu/moodle
1/18/05 Atoms and Stars, Class 2 1
Handouts
Class 2 Notes Midterm Questions, revised (Question 29 added) Initial the signin sheet IST 1990 photos
1/18/05 Atoms and Stars, Class 2 2
Due tonight
Report for Lab 1. A lab report has two parts, turned in as a single assignment (stapled):
o Data Sheet o Analysis
Your hypothesis fails if the experiment is inconsistent
o "Nature is the final arbiter" (judge) Q19
Hypotheses and experimental improvements not easy or automatic creativity needed
1/18/05 Atoms and Stars, Class 2 3
How Do We Know What Science Is?
Who says what the scientific method is?
o We listen to what scientists say they do, and watch them doing it
For example, Huxley (1863) and Copi (1986).
Exception: Frances Bacon present "at the birth" ~ 1600
Science is an open community, but to be taken seriously, you must take its methods and concerns seriously
o Galileo, Newton, Einstein and others were "mainstream" at first, revolutionary later
No exact definition of science that everyone agrees to, so looking at examples is a good method
1/18/05 Atoms and Stars, Class 2 4
Overview
Scientific Method (as opposed to content): We will do more here than typical science course Here, Atoms and Stars is about origins of modern Physical Science ("science") 1500 1700 AD in Europe
o Development of Greek philosophy in the area of science, and how it was overthrown by science
1/18/05 Atoms and Stars, Class 2 5
Overview (cont'd)
Scientific Method (cont'd): Modern Physical Science has roots going back to prehistory
o Its development still represents something new
Is this slow incremental change (roots) or a sudden change (development)?
o Both ("tipping point") o Analogy pile of sand in a dump truck
1/18/05 Atoms and Stars, Class 2 6
Overview
During development of science, much transmission by and (circa 1700) interaction with religion. Religion will come up.
1/18/05 Atoms and Stars, Class 2 7
Overview
My views (so you can evaluate what I say):
o Scientist, advocate of science - secure and reliable information to support action o At any time, science has limits, so it cannot be a complete basis for living: current shortcomings are human nature & interactions, place in world, purpose
Science skeptics be careful: science limits always expanding
o Member of church (Quakers, or Society of Friends), have taught Sunday School, been clerk, secretary, given counsel within the church.
A liberal church - I am liberal within that church.
o Also a Ph.D. physicist (technical qualification)
1/18/05 Atoms and Stars, Class 2 8
Overview
o You have right here to your beliefs, to state those beliefs, to question, to reject science
Grading on your understanding of the course material, including the basis for trusting science Science makes truth claims - what is the basis for believing those claims?
o I believe science and religion are compatible
Not all religious beliefs compatible with all science. But science is interconnected
Once you reject some science, hard to stop
1/18/05 Atoms and Stars, Class 2 9
Overview
Two pillars of science Q27:
o Data / observations / experiments
These make science reliable
o Hypotheses / laws / theories
These make science valuable Use in popular culture Vs. scientific usage Q29
In popular culture, "theory" usually means a passing thought, a possibility "just a theory" In science, a theory is an accepted and thoroughly tested explanation for a wide range of data the top of the line
1/18/05 Atoms and Stars, Class 2 10
Overview
#1: Data / observations / experiments
o Direct, not secondhand o Must be repeatable by anyone who cares to try
Often suggested by a hypotheses / law / theory, but must be repeatable even if you disagree Anything important is repeated Some things (speed of light) repeated for 100+ years
Improved technique triggers another round of measurements
1/18/05 Atoms and Stars, Class 2 11
Overview
#1: Data / observations / experiments (cont'd)
o If data from different scientists disagree, discrepancy must be checked and resolved not taken seriously until then o Results cannot depend on beliefs or preferences such effects must be checked and resolved o Often data suggested by a theory, but data stand even if theory fails
1/18/05 Atoms and Stars, Class 2 12
Overview
#1: Data / observations / experiments (cont'd)
o Must be recorded, not restricted or secret, with procedure (what you did, including preparation) and results (what you saw / measured)
So that others can repeat and verify your results
o Journals and raw notes kept, will be reviewed if questions arise
Skip to 22?
1/18/05 Atoms and Stars, Class 2 13
Overview
#2. Hypotheses / laws / theories
o Hypothesis: first step - a guess, explain the data o Law is older term, theory is newer term (less assured) o Accepted theory must:
Be capable of being disproven (falsifiability) Explain all (vast majority) data
Discrepancies must be addressed and eventually resolved
1/18/05 Atoms and Stars, Class 2 14
Overview
#2. Hypotheses / laws / theories (cont'd)
o Accepted theory must (continued):
Have direct evidence - not accepted just because rival theory fails
If two theories agree with data, must look for and do critical experiments that decide between them If two theories are inconsistent, this must be eventually be fixed
Be productive - predict new, unsuspected measurements, new phenomena, new results, which must be tested and which must agree
o Simpler theory preferred to more complicated
1/18/05 Atoms and Stars, Class 2 15
Overview
Typical sequence of advance (focus comes first and is assumed here) Q28:
1. Observation / Measurement 2. Description 3. Understanding (theory)
o Often this is first association (statistical) then causal
4. Control or technology (especially last 50 years)
Science is progressive: Q20
o Start in small area, expand
1/18/05 Atoms and Stars, Class 2 16
Overview
Science is progressive (cont'd)
o Later theory / experiment can change earlier theory
Example: Einstein's 1915 General Theory of Relativity changed ideas about his 1905 Theory of Special Relativity However, old results still correct but range extended
o Scientific knowledge provisional subject to change
1/18/05 Atoms and Stars, Class 2 17
Overview
Science is progressive (cont'd)
o Scientific knowledge can change rapidly at the frontier
Later experiments can show errors in the first ones Extending theory beyond data can introduce errors
Science is not:
o Fair theories do not have a right to be considered someone must want to do this
1/18/05 Atoms and Stars, Class 2 18
Overview
Science is not:
o Democratic no votes, nor formal consensus, theories can come "back to life" (string theory) o Not based on authority Newton and Einstein can be (were) wrong
Most scientists follow these rules but (with many scientists) there are many individual exceptions
1/18/05 Atoms and Stars, Class 2 19
Overview
Most scientists follow these rules but (with many scientists) there are many individual exceptions (continued)
o Science is social scientists help & check each other Q23 o Scientific arguments can be fierce
Issue about women and aggressive argument Our heroes the people who overthrew the established order Instant success: prove someone else wrong
o Scientists often become advocates of a theory
Social interaction corrects this
1/18/05 Atoms and Stars, Class 2 20
Overview
Scientists are skeptical about truth claims
o Many strongly-held beliefs have been shown to be wrong, e.g. common ideas about space o Many purely rational arguments have been shown to be wrong e.g. Aristotle o Experiments keep science correct and reliable
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Atoms and Stars, Class 2
21
Review of Essay Assignment
Due February 8 (three weeks) on diskette Topic: We have studied the process by which an earlier theory is replaced by a later one: (a) Aristotle's view that nature abhors a vacuum was replaced by the sea of air hypothesis and (b) the caloric theory of heat was replaced by Rumford's kinetic theory of heat. Following Copi's seven step account of the scientific method, explain how one of these transitions took place. Draw on material from the reading, class discussion, and the laboratory experiments. Also describe what this tells us about the scientific method.
1/18/05 Atoms and Stars, Class 2 22
Essay Assignment (cont'd)
3 to 4 pages, 12-point Times Roman, double-spaced, 1" margins top and bottom, 1" left and right. Content: 40%. Reading and understanding course materials, applying them to topic, consistent point of view
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Atoms and Stars, Class 2
23
Essay Assignment (cont'd)
Form: 40%. Title page, Introduction (roadmap), Body (organized, transitions between topics, detail to support general points), Conclusion (review content, draws to an end) Mechanics: 20%. Spelling, grammar, punctuation. Use spell-check and grammarcheck (note on passive) or dictionary.
1/18/05 Atoms and Stars, Class 2 24
Common Writing Problems
Functional grammar
o Rules of grammar have a purpose to transmit meaning o Rules of grammar are always changing o Different grammars for different groups o Get far too from the group's grammar and you are not understood (must change with changes) o The further you get from the group's grammar, the harder it is to understand you o Being able to use good standard grammar is like dressing well for a job interview
1/18/05 Atoms and Stars, Class 2 25
#1 Reason for Writing
To organize your own thinking
#1 Way to Good Writing
Have something you want to say
More Examples and Details
www.is.wayne.edu/olgt then link to Writing Guide, or The Everyday Writer Writing Center in 2310 UGL / 313-577-2544
1/18/05 Atoms and Stars, Class 2 26
Organization
Many possibilities for organization
o Historical o Logical o Specific to general, or general to specific o Combination
Signal transitions from one topic to another
o Paragraphs help here
1/18/05 Atoms and Stars, Class 2 27
Quick-and-Easy Organization
Write body first One you have figured out what you are going to say (the Body), write the Introduction and Conclusion afterwards Body should have general statements and specific examples and quotes
Skip to 36?
1/18/05 Atoms and Stars, Class 2 28
Sentences
A sentence:
o Verb (action) o Subject (did the action) o Complete thought o (starts with capital, period at end)
(Y/N) Because he hit the ball. (Y/N) John hit the ball.
1/18/05 Atoms and Stars, Class 2 29
Sentences
Is it a sentence? Consider it all by itself. Common sentence problem #1:
o Sentence fragment something that starts with a capital and ends with a period but is not a sentence
Because he hit the ball. John ran to first base. Fix by joining to main thought with a comma (,)
Because he hit the ball, John ran to first base.
1/18/05 Atoms and Stars, Class 2 30
Sentences
Is it a sentence? Consider it all by itself. Common sentence problem #2:
o Run-on sentence two or more sentences written as one
John hit the ball he ran to first base. Fix by breaking into two sentences
John hit the ball. He ran to first base.
Or by joining with semicolon (;) to show causality
John hit the ball; he ran to first base
1/18/05 Atoms and Stars, Class 2 31
Number (singular/plural)
Both subject and verb have number
o If these are not the same, signals conflict
Members join the club A member joins the club "One s"
Without a reason, do not change number from sentence to sentence
o (Bad) People should take care of their health. You should take your vitamins.
1/18/05 Atoms and Stars, Class 2 32
Tense (past, present, future)
Without a reason, do not change tense from sentence to sentence
Citations
"Scientific investigation is not, as many people seem to suppose, some kind of modern black art." (Huxley, 1) Cite the source even if you are paraphrasing
1/18/05 Atoms and Stars, Class 2 33
Punctuation
Apostrophe (`)
o Contraction o Possession (`s or s')
Some words inherently possessive, no ` (e.g. theirs)
o Never for pluralization
Lists
o Separate list items with commas (last one is optional) o If any list has a comma inside, separate items with semicolon
1/18/05 Atoms and Stars, Class 2 34
Wrong Word
Some words are commonly confused memorize or use list or dictionary
o its Vs it's o whose Vs who's o their Vs there o too Vs to o accept Vs except o Many, many more
End of writing section, on to something else
1/18/05 Atoms and Stars, Class 2 35
Readings
Huxley, "We Are All Scientists"
o Induction. Apples, Math compared to Red Shift o Deduction. Teapot and spoons Q5 o Must put a supposed theory or hypothesis to every test
(DB) Popper: science must be "falsifiable" single failure can be doom to a theory
o Hypothesis is normal
DB: science prefers:
o simple law before complicated one o universal law before specific
1/18/05 Atoms and Stars, Class 2 36
Readings (cont'd)
Copi, "Science and Hypothesis"
o o o o Recent, long after the birth of modern science Often uses Sherlock Holmes to illustrate Seven steps Science has
Practical benefit Value in itself as knowledge
o Scientists focus on a problem
Hypothesis to focus on pertinent facts Used to gather more facts "Aha" serious hypothesis - creative
1/18/05 Atoms and Stars, Class 2 37
Readings (cont'd)
Copi, "Science and Hypothesis"
o Finding consequences of hypothesis
DB: If none, "not science"
o Consequences must be tested o Application to problems
DB: Today, can lead to technology. Transistor, microchip, programmable computer, laser
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Atoms and Stars, Class 2
38
Readings (cont'd)
Copi, "Science and Hypothesis"
o Example of caloric theory of heat to kinetic Q22 o Caloric a substance, add it to matter, temperature goes up o Count Rumford worked on cannons
Boring generated very large amount of heat, could not believe you could mix in that much caloric What could you add a lot of? Motion, led to...
1/18/05 Atoms and Stars, Class 2 39
Readings (cont'd)
Copi, "Science and Hypothesis"
o Kinetic theory of heat o Sir Humphrey Davy compared theories, devised test
Two pieces of ice, keep them frozen, rub together. Caloric could not get in Did this, they melted, demonstrating kinetic theory
o Later, Joule more tests, also measurements
1/18/05 Atoms and Stars, Class 2 40
Before the Greeks...
Universe: about 15 billion years old Earth: about 5 billion years old
o Molten at first o Cooled off, land formed about 4 BYA
First life formed in seas about 3.7 BYA Earliest human-like animals (humanoids) evolved in southern Africa about 5 MYA
1/18/05
Atoms and Stars, Class 2
41
Before the Greeks...(Q21)
McClellan and Dorn, Science and Technology in World History Jared Diamond, Guns, Germs and St...