A1 F2015 Science
Transcript of A1 F2015 Science
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Quotes & Cartoon of the Day
• “If an elderly but distinguished scientist says that something is possible, he is almost certainly right; but if he says that it is impossible, he is very probably wrong. “
• -- Arthur C Clarke
• “The most exciting phrase to hear in science, the one that heralds new discoveries, is not 'Eureka!' but 'That's funny...' “
• -- Issac Asimov
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
This Class
• The paperwork that got missed last time
• What is Science?
• Definition
• The Scientific Method
• Recognizing Science
• What is Astronomy?
• Astronomy and Astrology
• In-class exercise: Numbers, Correlation and Causality aka “Allstate ICE”
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
• It was a warm summer evening in ancient Greece….
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
About Science
“Science is a way of trying not to fool yourself. The first principle is that you must not fool yourself, and you are the easiest person to fool.”
— Richard Feynman
Image credit: Tamiko Thiel
1984
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Definition
• Feynman’s definition is nearly perfect.
• There are many possible definitions, but they have some things in common.
• Science is based on facts.
• Science involves independent verification of facts
• Facts are established through observation and experimentation
• Through measurement
• Science strives to model and predict, precisely, how the universe behaves
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
What is a “fact”?
• “In science, ‘fact’ can only mean ‘confirmed to such a degree that it would be perverse to withhold provisional assent.’ I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms. “
--Stephen Jay Gould
• In the context of this class a fact is something that has been repeatedly verified.
• a close agreement by observers about the same phenomenon
• Facts can be subject to revision.
• usually at the detail level
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
What is NOT a “fact”?
• An authority or “expert” stating that something is true
• unless evidence can be presented.
• A first-person report that cannot be in any way proven, even if a number of people report the same experience
• It may point in the direction of a verifiable fact, but it also may not.
• “The plural of anecdote is not proof” -- attributed to Penn Jillette
• In Addition...
• The fact that two things are correlated does not prove causality
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Some ways I think about Science
• The construction of predictive working models -- “theories” -- which accurately predict how the natural world “works”.
• And the body of knowledge that results
• “Cosmic Forensics” -- the systematic and careful collection of evidence in order to prove or disprove a notion about how the natural world works.
• A social contract -- a way of pursuing knowledge that minimizes (but cannot ever eliminate) the impact of human emotion, greed and fallibility.
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
One version of the Scientific Method
• Observation/Background research
• Formulation of a hypothesis
• Use hypothesis to predict phenomena or quantitative results.
• Performance of experimental tests or observations
• quantitative
• Revision of the hypothesis if needed and repetition of prediction/experiment
• independent investigators
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Negative Results
“No amount of experimentation can ever prove me right; a single experiment can prove me wrong.”
-- Albert Einstein
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Nomenclature: Hypothesis
• Hypothesis = a proposed explanation for a phenomenon
• can be little more than a guess
• a good hypothesis has predictive value/can be tested
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Nomenclature: Theory
• Theory:
• A coherent group of well-tested and supported hypotheses, or summary of a key hypotheses, commonly regarded as correct, that can be used as principles of explanation and prediction for a class of phenomena: e.g., Einstein's theory of relativity; the Big Bang Theory.
• accurately describes how reality works & accounts for all known facts.
• valid until evidence contradicts it
• not all hypotheses “grow up” to be theories, even if they are well-supported
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Theories & Models aren’t Reality itself
• subject to change or refinement when new facts are uncovered.
• exquisitely detailed, predictive model of reality.
• To argue that a theory IS reality is philosophy, not science
• This is a mistake many scientists make
• Newton’s Gravity & General Relativity -- a paradigm shift
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
The most important characteristic of a good hypothesis is _____.
A. that it addresses a current “hot topic”
B. that it predicts testable consequences
C. that it represents a huge leap forward
D. that it is almost certainly true
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Which of these is not a scientific hypothesis?
A. Protons carry an electric charge.
B. Undetectable particles are some of nature’s secrets.
C. Charged particles will change direction when moving in the Earth’s magnetic field.
D. All of the above
E. None of the above
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Larry Bird once said, “I've got a theory that if you give 100% all of the time, somehow things will work out in the end.”
From the standpoint of science, which of the following words would most accurately replace the word “theory” in this quote?
A. theory
B. belief
C. hypothesis
D. law
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
“The good thing about science is that it's true whether or not you believe in it.”
― Neil deGrasse Tyson
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
What isn’t Science?
• Belief systems
• religion, philosophy, coherent sets of beliefs
• certainty without proof, faith
• Superstition
• Testimonials/Anecdotes
• Pseudoscience
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Important
• A belief system is not science, but that does not mean that all scientists think it is “wrong” or lacking in value.
“I do not feel obliged to believe that the same God who has endowed us with sense, reason, and intellect has intended us to forgo their use. “
-- Galileo Gallilei
“Science investigates; religion interprets. Science gives man knowledge, which is power; religion gives man wisdom, which is control. Science deals mainly with facts; religion deals mainly with values. The two are not rivals.”
-- Martin Luther King, Jr.
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Pseudoscience
• Claim, belief, or practice presented as scientific, but lacking scientific status
• no valid scientific method
• lacks supporting evidence or plausibility
• cannot be reliably tested -- or has been tested and repeatedly failed!
• Per Wikipedia: “Often characterized by the use of vague, contradictory, exaggerated or unprovable claims, an over-reliance on confirmation rather than rigorous attempts at refutation, a lack of openness to evaluation by other experts, and a general absence of systematic processes to rationally develop theories.”
• Looks like science, but when you scratch the surface...
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Examples of Pseudoscience
• Astrology
• 2012 Apocalypse
• Von Daniken -- Ancient Astronauts
• Alchemy
• Homeopathy
• holistic approaches can be scientific
• Pyramid powers
• Intelligent Design
• Numerology
• Aura Analysis
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Why Astronomers Roll their eyes when you say “Horoscope”
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
(Modern) Astrology is not a Science
• In Antiquity there was overlap with what we now call Astronomy
• cataloguing & describing the content & motion of the night sky
• observation of correlations between the sky & things affecting humans
• The days are longer and the weather is warmer when certain constellations are visible
• Telescopes had not been invented
• nature of the stars and planets was a matter of speculation with relatively little ability to secure proof.
• Life was believed to begin with birth
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
(Modern) Astrology is not a Science
• HOWEVER
• No known scientific theory predicts any possible interaction between human affairs and the apparent location of the Sun, Moon and planets a
• Repeated attempts have been made to observe and verify correlations between astrological predictions and actual events and EVERY SINGLE ONE HAS FAILED TO FIND A MEASURABLE CORRELATION.
• The actual behavior of the sky has grown out of synch with the ancient tables and charts and attempts to update it have been rejected
• Are you an Ophiucus?
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Try this
• Find a dozen or so horoscopes online or at the newsstand. To what extent do the predictions for a given sign agree or disagree?
• For a couple of weeks, don’t read your horoscope but have someone save it aside for you. Journal how your day went each day. At the end of the week, see how well the journal entries compare to your horoscopes for the time period.
Astronomy 1 — Elementary Astronomy LA Mission College
Spring F2015
In-Class Exercise
Allstate & Astrology
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Lies, damned lies & statistics
• “Figures often beguile me, particularly when I have the arranging of them myself; in which case the remark attributed to Disraeli would often apply with justice and force: "There are three kinds of lies: lies, damned lies and statistics."”
• - Mark Twain's Own Autobiography: The Chapters from the North American Review
Astronomy 1 - Elementary Astronomy LA Mission College Levine F2015
Topic for Next Class
• What is Science?
• What isn’t Science
• What is Astronomy?