Science & pseudoscience –Part of chapter 1

Including guest appearance by religion & popular (but incorrect) culture

Study pages 9-18 in chapter 1

(Pages 1-8 also interesting, but more related to astronomy than physics)

Goals & Outcomes• Appreciating science in general, and physics in

specific.

• Distinguishing scientific from non-scientific work, and therefore understanding what science is.

• Developing a working knowledge of the scientific method and how to apply it to real world situations.

• Judge whether a particular study is a science or a “pseudo-science” using the scientific method.

Learning Objectives

• Understand the Scientific method– Limitations to pure objectivity– Compare to non-scientific analysis & religion

• Understand the definitions of the word “theory” as used by scientists compared to non-scientists

• Understand what kinds of questions can and cannot be addressed by science

• Know some of the “tricks” of pseudoscience that make it so believable.

Scientific Method

5. Share results/ ideas with others (not in book)

Science is useless if nobody learns!

4. TEST IT - Careful experiments to determine if

observations disprove the hypothesis. Try to isolate the cause/effect -- Control groups, examine only one thing at a time, remove psychological effects.

3. Make a prediction about something new

2. Form hypothesis = model of nature

1. Make observations - Ask a question

Cyclical process – can (re-)start anywhere in the cycle.

6. If hypothesis fails: Revise or reject the hypothesis

If hypothesis didn’t fail:Look for new predictions Real world

Real biases

Personalities(Objectivity)

Calif. Elementary School Science Standards for scientific inquiry

• From California Science Standards, taken from throughout the K-12 standards

– What is science?• Scientific progress is made by asking meaningful questions

and conducting careful investigations.– Distinguish between hypothesis and theory as scientific terms.

– Recognize the usefulness and limitations of models and theories as scientific representations of reality.

– Ask question• Develop a testable question.

Calif. Elementary School Science Standards for scientific inquiry

• From California Science Standards, taken from throughout the K-12 standards

– Predictions:• Make predictions based on observed patterns and not random

guessing.

• Predict the outcome of a simple investigation and compare the result with the prediction.

• Formulate and justify predictions based on cause-and-effect relationships

Calif. Elementary School Science Standards for scientific inquiry

• From California Science Standards, taken from throughout the K-12 standards

– Testing hypotheses:• Collect data in an investigation and analyze those data to develop a

logical conclusion.• Repeat observations to improve accuracy and know that the results of

similar scientific investigations seldom turn out exactly the same because of differences in the things being investigated, methods being used, or uncertainty in the observation.

• Conduct multiple trials to test a prediction and draw conclusions about the relationships between predictions and results.

• Differentiate evidence from opinion and know that scientists do not rely on claims or conclusions unless they are backed by observations that can be confirmed.

• Evaluate the accuracy and reproducibility of data. • Identify and communicate sources of unavoidable experimental error.

Calif. Elementary School Science Standards for scientific inquiry

• From California Science Standards, taken from throughout the K-12 standards

– Communication:• Communicate observations orally and through drawings.

Draw pictures that portray some features of the thing being described.

• Record observations and data with pictures, numbers, or written statements.

• Record observations on a bar graph.

• Communicate the steps and results from an investigation in written reports and oral presentations.

• Identify and communicate sources of unavoidable experimental error.

Calif. Elementary School Science Standards for scientific inquiry

• From California Science Standards, taken from throughout the K-12 standards

– Revising scientific models:• Formulate explanations by using logic and evidence.

• Recognize whether evidence is consistent with a proposed explanation.

• Make new observations when discrepancies exist between two descriptions of the same object or phenomenon.

• Identify possible reasons for inconsistent results, such as sources of error or uncontrolled conditions.

• Know that when an observation does not agree with an accepted scientific theory, the observation is sometimes mistaken or fraudulent (e.g., the Piltdown Man fossil or unidentified flying objects) and that the theory is sometimes wrong (e.g., the Ptolemaic model of the movement of the Sun, Moon, and planets).

Calif. Elementary School Science Standards for scientific inquiry

• From California Science Standards, taken from throughout the K-12 standards

– Human influences:• Differentiate observation from inference (interpretation) and

know scientists’ explanations come partly from what they observe and partly from how they interpret their observations.

• Know that when an observation does not agree with an accepted scientific theory, the observation is sometimes mistaken or fraudulent (e.g., the Piltdown Man fossil or unidentified flying objects) and that the theory is sometimes wrong (e.g., the Ptolemaic model of the movement of the Sun, Moon, and planets).

• Differentiate evidence from opinion and know that scientists do not rely on claims or conclusions unless they are backed by observations that can be confirmed.

Hallmarks of Science(Good scientific theories / good science)

There are 3 big ideas about “science” vs. other kinds of thinking.

1. Have TESTABLE predictions

TESTABLE means you must be able to prove the idea WRONG

2. Seek NATURAL explanations of observations

Why natural? Those can be disproved! (blue circle)

These first two usually split science and religion.

3. Pick the simplest model that explains observations. (Occam’s razor)

4. Make sure experiment is repeatable

Good science doesn’t need to be CORRECT. Very few good scientific ideas ARE right, they often need modifications. Examples:

• quantum physics, theory of relativity, “law of gravity.”

What’s in a name? Theories

Guess – any old random idea to explain observations

Hypothesis – an idea that can be tested

Theory – a hypothesis that has been tested a LOT & has passed them all, explaining many aspects of nature.

It can be wrong, but according to current research, that isn’t likely.

Usually only needs minor modifications, if any.

Everyday English uses “guess,” “theory,” and “hypothesis” as synonyms.

Scientists do not.

A scientific Theory, like evolution, is NOT just a guess.

Evolution is the only good model that is backed by tests, data, and evidence. It is the only scientific model of life.

California Elementary School Science Standards for evolution

• From California Science Standards, grade 7– Biological evolution accounts for the

diversity of species developed through gradual processes over many generations.

Religion vs. ScienceNo scientist claims a theory is definitely correct/perfect.

Theories can always be disproven later. (Gravity.)

All scientific matters can be tested. Not all religious ideas can be tested.

Science does NOT contradict religion

Science:

• how processes appear to be related.

• rules that nature follows

• NOT why these rules work.

Science is testable

It’s religion if you can’t do an experiment to prove it wrong. Faith

Religion isn’t always testable. That doesn’t mean it’s wrong!

(Pseudo) Anti-Sciencepseudo = false

Common and popular examples:

•Creationism(Intelligent design)

•Astrology

•Palm reading, Tarot cards

---------------- Religion with science words(NOT science; don’t teach it in science class)

---------------- Predicting future by birth date

20 million people = same birthday; 4 births per sec.10,000 babies born in US every day.(1 per 8 seconds)

- Semi-legit! Acting mixed with spoken & body language interpretations! Personality reading!

Astrology, Palm Reading, etc. tend to make very general predictions which YOU then match to observations of your life. Or they ask leading questions, and they follow your lead.

Fortune Tellers / Psychics

I’m on a soapbox for this slide…Anti-Science in popular American culture

• No scientific study has linked vaccines to having autism.– There used to be one science study, but it was recently disproven

– Many scientific studies link lack-of-vaccines to getting sick.

– In first half of 2008, measles more than tripled in the USA.

– Most cases were kids who didn’t get a vaccine, fearing autism.

– Measles can kill you. It is contagious.

–VACCINES SAVE LIVES!– See http://www.sciencebasedmedicine.org/?p=384

• Almost all (90+%) science indicates global warming is human-caused and will cause environmental and financial damage over the next 100 years.– My generation can’t / won’t fix the problem.

– Your generation will have to.

By definition, a scientific theory can also be a fact

0

0 1. True

2. False

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

41 42 43 44 45 46 47 48 49 50 51 52 53 54 55

What is Physics?• Physics seeks to find the overall GENERAL set

of rules that nature follows.– See pages 16-17 for details

• Compare to other sciences and related field:– Biology: rules for living things

– Chemistry: rules for atoms and molecules

– Geology: rules for planets

– Astronomy: rules for everything not on Earth

– Engineering: building things from these rules

• Physics really is the most important science. (Astronomy is next, in my opinion. )

SummaryScience

Testable

No conflict with religion

How can we test that? How can we know?

Physics is the most important science. And it’s phun!

Homework: DUE NEXT CLASS:

End-of-chapter 1 questions 11, 12, 13

If you don’t/won’t have a book, copy the questions from me or a classmate after class.