66 ideas
21239 | Philosophers are marked by a joint love of evidence and ambiguity [Merleau-Ponty] |
17979 | Research shows perceptual discrimination is sharper at category boundaries [Murphy] |
18690 | Induction is said to just compare properties of categories, but the type of property also matters [Murphy] |
17980 | The main theories of concepts are exemplar, prototype and knowledge [Murphy] |
17969 | The classical definitional approach cannot distinguish typical and atypical category members [Murphy] |
17973 | The theoretical and practical definitions for the classical view are very hard to find [Murphy] |
17970 | Classical concepts follow classical logic, but concepts in real life don't work that way [Murphy] |
17971 | Classical concepts are transitive hierarchies, but actual categories may be intransitive [Murphy] |
17972 | The classical core is meant to be the real concept, but actually seems unimportant [Murphy] |
17975 | There is no 'ideal' bird or dog, and prototypes give no information about variability [Murphy] |
17976 | Prototypes are unified representations of the entire category (rather than of members) [Murphy] |
18691 | The prototype theory uses observed features, but can't include their construction [Murphy] |
17983 | The prototype theory handles hierarchical categories and combinations of concepts well [Murphy] |
17985 | Prototypes theory of concepts is best, as a full description with weighted typical features [Murphy] |
17986 | Learning concepts is forming prototypes with a knowledge structure [Murphy] |
17974 | The most popular theories of concepts are based on prototypes or exemplars [Murphy] |
17977 | The exemplar view of concepts says 'dogs' is the set of dogs I remember [Murphy] |
17987 | The concept of birds from exemplars must also be used in inductions about birds [Murphy] |
17982 | Exemplar theory struggles with hierarchical classification and with induction [Murphy] |
17981 | Children using knowing and essentialist categories doesn't fit the exemplar view [Murphy] |
17984 | Conceptual combination must be compositional, and can't be built up from exemplars [Murphy] |
17978 | We do not learn concepts in isolation, but as an integrated part of broader knowledge [Murphy] |
18687 | Concepts with familiar contents are easier to learn [Murphy] |
18688 | Some knowledge is involved in instant use of categories, other knowledge in explanations [Murphy] |
18689 | People categorise things consistent with their knowledge, even rejecting some good evidence [Murphy] |
21167 | Gravity is unusual, in that it always attracts and never repels [New Sci.] |
21176 | In the Big Bang general relativity fails, because gravity is too powerful [New Sci.] |
21147 | Quantum electrodynamics incorporates special relativity and quantum mechanics [New Sci.] |
21155 | Photons have zero rest mass, so virtual photons have infinite range [New Sci.] |
21161 | In the standard model all the fundamental force fields merge at extremely high energies [New Sci.] |
21146 | Electrons move fast, so are subject to special relativity [New Sci.] |
21148 | The strong force is repulsive at short distances, strong at medium, and fades at long [New Sci.] |
21152 | The strong force binds quarks tight, and the nucleus more weakly [New Sci.] |
21151 | Gluons, the particles carrying the strong force, interact because of their colour charge [New Sci.] |
21150 | Three different colours of quark (as in the proton) can cancel out to give no colour [New Sci.] |
21142 | Classifying hadrons revealed two symmetry patterns, produced by three basic elements [New Sci.] |
21143 | Quarks in threes can build hadrons with spin ½ or with spin 3/2 [New Sci.] |
21154 | Three particles enable the weak force: W+ and W- are charged, and Z° is not [New Sci.] |
21156 | The weak force particles are heavy, so the force has a short range [New Sci.] |
21164 | Why do the charges of the very different proton and electron perfectly match up? [New Sci.] |
21170 | The Standard Model cannot explain dark energy, survival of matter, gravity, or force strength [New Sci.] |
21145 | The four fundamental forces (gravity, electromagnetism, weak and strong) are the effects of particles [New Sci.] |
21153 | The weak force explains beta decay, and the change of type by quarks and leptons [New Sci.] |
21157 | Particles are spread out, with wave-like properties, and higher energy shortens the wavelength [New Sci.] |
21158 | Fermions, with spin ½, are antisocial, and cannot share quantum states [New Sci.] |
21165 | Spin is akin to rotation, and is easily measured in a magnetic field [New Sci.] |
21149 | Quarks have red, green or blue colour charge (akin to electric charge) [New Sci.] |
21140 | Spin is a built-in ration of angular momentum [New Sci.] |
21163 | The mass of protons and neutrinos is mostly binding energy, not the quarks [New Sci.] |
21168 | Gravitional mass turns out to be the same as inertial mass [New Sci.] |
21138 | Neutrons are slightly heavier than protons, and decay into them by emitting an electron [New Sci.] |
21144 | Top, bottom, charm and strange quarks quickly decay into up and down [New Sci.] |
21141 | Neutrinos were proposed as the missing energy in neutron beta decay [New Sci.] |
21169 | Only neutrinos spin anticlockwise [New Sci.] |
21166 | Standard antineutrinos have opposite spin and opposite lepton number [New Sci.] |
21171 | The symmetry of unified electromagnetic and weak forces was broken by the Higgs field [New Sci.] |
21175 | String theory might be tested by colliding strings to make bigger 'stringballs' [New Sci.] |
21177 | String theory offers a quantum theory of gravity, by describing the graviton [New Sci.] |
21178 | String theory is now part of 11-dimensional M-Theory, involving p-branes [New Sci.] |
21179 | Supersymmetric string theory can be expressed using loop quantum gravity [New Sci.] |
21162 | Only supersymmetry offers to incorporate gravity into the scheme [New Sci.] |
21172 | The evidence for supersymmetry keeps failing to appear [New Sci.] |
21173 | Supersymmetry says particles and superpartners were unities, but then split [New Sci.] |
21159 | Supersymmetry has extra heavy bosons and heavy fermions [New Sci.] |
21160 | The Higgs field means even low energy space is not empty [New Sci.] |
21174 | Dark matter must have mass, to produce gravity, and no electric charge, to not reflect light [New Sci.] |