Science. What it is Why it s important to know about it Elements of the scientific method

Transcription

1 Science What it is Why it s important to know about it Elements of the scientific method

2 DEFINITIONS OF SCIENCE: Attempts at a one-sentence description Science is the search for the perfect means of attaining any end The whole of science is after all nothing but a refinement of everyday thinking. Science is organized knowledge Science is a method for the description, creation and understanding of human experience Science is distinguished by testing ideas with measurements the scientific method

3 The character of science Science is a social enterprise o I am among those who think that science has a great beauty. We should not allow it to be believed that all scientific progress can be reduced to mechanisms, machines, gearings, even though such machinery also has its own beauty. Marie Curie

4 Ignorance of science American high school students perform worse than 21 other countries Spending on research declines Fewer scientists are produced 50 % of the population dismiss evolutionary biology (Live from Moody, dinosaurs were on the Ark!) Rush Limbaugh is an authority on climate change

5 Fear of science and embracing magic Scientific developments under siege o Useful applications of nuclear power Eliminating E-Coli from vegetables with radiation Replacement for fossil fuels o Stem cell research Combating genetic diseases o Genetic engineering of crops Defeating food shortages The book Natural Cures They Don t Want You to Know About was a top ten seller for more than a year

6 Attitudes of the scientist Curiosity Open mind Interest in knowledge Courage of convictions Capability of abandoning beliefs in the light of new knowledge Skeptical Critical

7 Tools of the trade Ways of dealing with information and thinking scientifically: Laws and Theories HYPOTHESIS: an educated guess derived from various assumptions which can be tested using a range of methods; a proposition put forward for proof or discussion

8 LAW A rule which describes specified natural phenomena within the limits of experimental observation (LDST) Broadly applicable generalization that summarizes some aspect of the natural world (Tro) Ohm s Law, Gravity, Boyle s Law Scientific laws are precise, can be reduced to mathematical expressions Laws have limited regions of application - don't always work in all situations Laws do not provide understanding of why things happen Laws cannot be extrapolated

9 THEORY Confirmed explanation of phenomena; a hypothesis tested and confirmed with facts (scientific evidence) not previously known (CCTD) A scheme or system of ideas or statements held as an explanation or account of a group of facts or phenomena; a hypothesis that has been confirmed or established by observation or experiment, and is accepted as accounting for the known facts (OED) A model that describes the underlying cause of physical behavior. (Tro)

10 It s only a theory Is a theory ever fact - true? o o o o o Facts are observations while theories are explanations Difficult to say theory is correct even after predictions proved It is acceptable to say theory works well However, new results may falsify the theory Theory of relativity demonstrated limitations in Newtonian mechanics. Now relativity is being challenged by new results. Theories are modified to explain new observations Theories have predictive power o Prediction of existence of subatomic particles from quantum theory Theories provide understanding of why things happen

11 Pressure (atm) Law and Theory contrasted using gases Boyle s Law (17 th century) o Experimental observation of relationship between pressure and volume of a gas Kinetic theory of gases (19 th century) o Mathematical derivation of observed gas law using postulate that a gas consists of molecules which can be treated like small hard spheres in random motion. The behaviour of the gas is predicted using known mechanics of spheres P vs V Volume (L)

12 Scientific method more than one way to skin a cat

13 Observation vs imagination Imagination plays an increasingly important role in science. Inductive approach relies wholly on observation to develop a theory ( And God forbid we should offer the dreams of fancy for a model of the world ) Newton offered: hypotheses... have no place in experimental philosophy. Deductive relies on imagination. More important today. Hypothesis may originate purely in the realm of the imagination, using also some known mathematical relations. Kekule s dream about the structure of benzene

14 Technology and science Technology is human activity directed toward satisfaction of human needs by more effective use of environment Technology is obtaining a better living from resources - making gadgets and tools Technology is not a contemplative activity, except where it is used in the design of new things; the pondering is directed towards a specific practical goal, not contemplation for its own sake Technology also gives rise to science as its tools and things are invented Technology is older than science: early man made a club to get food, not because it seemed like an interesting thing to do

15 RELATIONS BETWEEN SCIENCE AND TECHNOLOGY The relationship between science and technology in history has not always been clear, and it has not been easy to say which influenced which. STEAM ENGINE DEVELOPMENT: Science had nothing to do with the invention of the steam engine Science benefited from its invention Perfecting the steam engine was not made by engineers/technologists but by a basic scientist (Carnot). His work on heat flow led to thermodynamics. Thus: technology developed a steam engine, which lead to scientific thought and discovery of new scientific relationships - thermodynamics.

16 Basic Research and Technology Faraday was a scientist who demonstrated that magnetism generated electricity. This led to development of electrical supply industry in which Faraday had no significant part. Edison exploited electromagnetism in development of new technology Basic research produces new knowledge that results in new technology in unpredictable ways over long time periods: magnetic domains from the study of magnetism for example, which resulted in new magnetic materials.

17 TENSION BETWEEN BENEFITS AND COSTS Risks and rewards Technology has meant a vast increase in the production and consumption of energy Technology has enabled massive growth in population greater competition for resources Technology has brought enormous benefits and problems Solutions to problems depend on greater investment in science, not turning the clock back