64 ideas
12223 | It is a fallacy to explain the obscure with the even more obscure [Hale/Wright] |
Full Idea: The fallacy of 'ad obscurum per obscurius' is to explain the obscure by appeal to what is more obscure. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §3) | |
A reaction: Not strictly a fallacy, so much as an example of inadequate explanation, along with circularity and infinite regresses. |
17925 | Showing a disproof is impossible is not a proof, so don't eliminate double negation [Colyvan] |
Full Idea: In intuitionist logic double negation elimination fails. After all, proving that there is no proof that there can't be a proof of S is not the same thing as having a proof of S. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) | |
A reaction: I do like people like Colyvan who explain things clearly. All of this difficult stuff is understandable, if only someone makes the effort to explain it properly. |
17926 | Rejecting double negation elimination undermines reductio proofs [Colyvan] |
Full Idea: The intuitionist rejection of double negation elimination undermines the important reductio ad absurdum proof in classical mathematics. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) |
17924 | Excluded middle says P or not-P; bivalence says P is either true or false [Colyvan] |
Full Idea: The law of excluded middle (for every proposition P, either P or not-P) must be carefully distinguished from its semantic counterpart bivalence, that every proposition is either true or false. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) | |
A reaction: So excluded middle makes no reference to the actual truth or falsity of P. It merely says P excludes not-P, and vice versa. |
12230 | Singular terms refer if they make certain atomic statements true [Hale/Wright] |
Full Idea: Anyone should agree that a justification for regarding a singular term as having objectual reference is provided just as soon as one has justification for regarding as true certain atomic statements in which it functions as a singular term. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §9) | |
A reaction: The meat of this idea is hidden in the word 'certain'. See Idea 10314 for Hale's explanation. Without that, the proposal strikes me as absurd. |
17929 | Löwenheim proved his result for a first-order sentence, and Skolem generalised it [Colyvan] |
Full Idea: Löwenheim proved that if a first-order sentence has a model at all, it has a countable model. ...Skolem generalised this result to systems of first-order sentences. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 2.1.2) |
17930 | Axioms are 'categorical' if all of their models are isomorphic [Colyvan] |
Full Idea: A set of axioms is said to be 'categorical' if all models of the axioms in question are isomorphic. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 2.1.2) | |
A reaction: The best example is the Peano Axioms, which are 'true up to isomorphism'. Set theory axioms are only 'quasi-isomorphic'. |
10631 | If 'x is heterological' iff it does not apply to itself, then 'heterological' is heterological if it isn't heterological [Hale/Wright] |
Full Idea: If we stipulate that 'x is heterological' iff it does not apply to itself, we speedily arrive at the contradiction that 'heterological' is itself heterological just in case it is not. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.2) |
17928 | Ordinal numbers represent order relations [Colyvan] |
Full Idea: Ordinal numbers represent order relations. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.2.3 n17) |
17923 | Intuitionists only accept a few safe infinities [Colyvan] |
Full Idea: For intuitionists, all but the smallest, most well-behaved infinities are rejected. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.3) | |
A reaction: The intuitionist idea is to only accept what can be clearly constructed or proved. |
17941 | Infinitesimals were sometimes zero, and sometimes close to zero [Colyvan] |
Full Idea: The problem with infinitesimals is that in some places they behaved like real numbers close to zero but in other places they behaved like zero. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 7.1.2) | |
A reaction: Colyvan gives an example, of differentiating a polynomial. |
17922 | Reducing real numbers to rationals suggested arithmetic as the foundation of maths [Colyvan] |
Full Idea: Given Dedekind's reduction of real numbers to sequences of rational numbers, and other known reductions in mathematics, it was tempting to see basic arithmetic as the foundation of mathematics. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 1.1.1) | |
A reaction: The reduction is the famous Dedekind 'cut'. Nowadays theorists seem to be more abstract (Category Theory, for example) instead of reductionist. |
17936 | Transfinite induction moves from all cases, up to the limit ordinal [Colyvan] |
Full Idea: Transfinite inductions are inductive proofs that include an extra step to show that if the statement holds for all cases less than some limit ordinal, the statement also holds for the limit ordinal. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1 n11) |
10624 | The incompletability of formal arithmetic reveals that logic also cannot be completely characterized [Hale/Wright] |
Full Idea: The incompletability of formal arithmetic reveals, not arithmetical truths which are not truths of logic, but that logical truth likewise defies complete deductive characterization. ...Gödel's result has no specific bearing on the logicist project. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], §2 n5) | |
A reaction: This is the key defence against the claim that Gödel's First Theorem demolished logicism. |
8784 | Neo-logicism founds arithmetic on Hume's Principle along with second-order logic [Hale/Wright] |
Full Idea: The result of joining Hume's Principle to second-order logic is a consistent system which is a foundation for arithmetic, in the sense that all the fundamental laws of arithmetic are derivable within it as theorems. This seems a vindication of logicism. | |
From: B Hale / C Wright (Logicism in the 21st Century [2007], 1) | |
A reaction: The controversial part seems to be second-order logic, which Quine (for example) vigorously challenged. The contention against most attempts to improve Frege's logicism is that they thereby cease to be properly logical. |
8787 | The Julius Caesar problem asks for a criterion for the concept of a 'number' [Hale/Wright] |
Full Idea: The Julius Caesar problem is the problem of supplying a criterion of application for 'number', and thereby setting it up as the concept of a genuine sort of object. (Why is Julius Caesar not a number?) | |
From: B Hale / C Wright (Logicism in the 21st Century [2007], 3) | |
A reaction: One response would be to deny that numbers are objects. Another would be to derive numbers from their application in counting objects, rather than the other way round. I suspect that the problem only real bothers platonists. Serves them right. |
17940 | Most mathematical proofs are using set theory, but without saying so [Colyvan] |
Full Idea: Most mathematical proofs, outside of set theory, do not explicitly state the set theory being employed. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 7.1.1) |
17931 | Structuralism say only 'up to isomorphism' matters because that is all there is to it [Colyvan] |
Full Idea: Structuralism is able to explain why mathematicians are typically only interested in describing the objects they study up to isomorphism - for that is all there is to describe. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 3.1.2) |
10629 | If structures are relative, this undermines truth-value and objectivity [Hale/Wright] |
Full Idea: The relativization of ontology to theory in structuralism can't avoid carrying with it a relativization of truth-value, which would compromise the objectivity which structuralists wish to claim for mathematics. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.2 n26) | |
A reaction: This is the attraction of structures which grow out of the physical world, where truth-value is presumably not in dispute. |
10628 | The structural view of numbers doesn't fit their usage outside arithmetical contexts [Hale/Wright] |
Full Idea: It is not clear how the view that natural numbers are purely intra-structural 'objects' can be squared with the widespread use of numerals outside purely arithmetical contexts. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.2 n26) | |
A reaction: I don't understand this objection. If they refer to quantity, they are implicitly cardinal. If they name things in a sequence they are implicitly ordinal. All users of numbers have a grasp of the basic structure. |
17932 | If 'in re' structures relies on the world, does the world contain rich enough structures? [Colyvan] |
Full Idea: In re structuralism does not posit anything other than the kinds of structures that are in fact found in the world. ...The problem is that the world may not provide rich enough structures for the mathematics. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 3.1.2) | |
A reaction: You can perceive a repeating pattern in the world, without any interest in how far the repetitions extend. |
8788 | Logicism is only noteworthy if logic has a privileged position in our ontology and epistemology [Hale/Wright] |
Full Idea: It is only if logic is metaphysically and epistemologically privileged that a reduction of mathematical theories to logical ones can be philosophically any more noteworthy than a reduction of any mathematical theory to any other. | |
From: B Hale / C Wright (Logicism in the 21st Century [2007], 8) | |
A reaction: It would be hard to demonstrate this privileged position, though intuitively there is nothing more basic in human rationality. That may be a fact about us, but it doesn't make logic basic to nature, which is where proper reduction should be heading. |
10622 | The neo-Fregean is more optimistic than Frege about contextual definitions of numbers [Hale/Wright] |
Full Idea: The neo-Fregean takes a more optimistic view than Frege of the prospects for the kind of contextual explanation of the fundamental concepts of arithmetic and analysis (cardinals and reals), which he rejected in 'Grundlagen' 60-68. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], §1) |
8783 | Logicism might also be revived with a quantificational approach, or an abstraction-free approach [Hale/Wright] |
Full Idea: Two modern approaches to logicism are the quantificational approach of David Bostock, and the abstraction-free approach of Neil Tennant. | |
From: B Hale / C Wright (Logicism in the 21st Century [2007], 1 n2) | |
A reaction: Hale and Wright mention these as alternatives to their own view. I merely catalogue them for further examination. My immediate reaction is that Bostock sounds hopeless and Tennant sounds interesting. |
12225 | Neo-Fregeanism might be better with truth-makers, rather than quantifier commitment [Hale/Wright] |
Full Idea: A third way has been offered to 'make sense' of neo-Fregeanism: we should reject Quine's well-known criterion of ontological commitment in favour of one based on 'truth-maker theory'. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §4 n19) | |
A reaction: [The cite Ross Cameron for this] They reject this proposal, on the grounds that truth-maker theory is not sufficient to fix the grounding truth-conditions of statements. |
12224 | Are neo-Fregeans 'maximalists' - that everything which can exist does exist? [Hale/Wright] |
Full Idea: It is claimed that neo-Fregeans are committed to 'maximalism' - that whatever can exist does. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §4) | |
A reaction: [The cite Eklund] They observe that maximalism denies contingent non-existence (of the £20 note I haven't got). There seems to be the related problem of 'hyperinflation', that if abstract objects are generated logically, the process is unstoppable. |
12226 | The identity of Pegasus with Pegasus may be true, despite the non-existence [Hale/Wright] |
Full Idea: Identity is sometimes read so that 'Pegasus is Pegasus' expresses a truth, the non-existence of any winged horse notwithstanding. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §5) | |
A reaction: This would give you ontological commitment to truth, without commitment to existence. It undercuts the use of identity statements as the basis of existence claims, which was Frege's strategy. |
12229 | Maybe we have abundant properties for semantics, and sparse properties for ontology [Hale/Wright] |
Full Idea: There is a compatibilist view which says that it is for the abundant properties to play the role of 'bedeutungen' in semantic theory, and the sparse ones to address certain metaphysical concerns. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §9) | |
A reaction: Only a philosopher could live with the word 'property' having utterly different extensions in different areas of discourse. They similarly bifurcate words like 'object' and 'exist'. Call properties 'quasi-properties' and I might join in. |
18443 | A successful predicate guarantees the existence of a property - the way of being it expresses [Hale/Wright] |
Full Idea: The good standing of a predicate is already trivially sufficient to ensure the existence of an associated property, a (perhaps complex) way of being which the predicate serves to express. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §9) | |
A reaction: 'Way of being' is interesting. Is 'being near Trafalgar Sq' a way of being? I take properties to be 'features', which seems to give a clearer way of demarcating them. They say they are talking about 'abundant' (rather than 'sparse') properties. |
10626 | Objects just are what singular terms refer to [Hale/Wright] |
Full Idea: Objects, as distinct from entities of other types (properties, relations or, more generally, functions of different types and levels), just are what (actual or possible) singular terms refer to. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.1) | |
A reaction: I find this view very bizarre and hard to cope with. It seems either to preposterously accept the implications of the way we speak into our ontology ('sakes'?), or preposterously bend the word 'object' away from its normal meaning. |
17943 | Probability supports Bayesianism better as degrees of belief than as ratios of frequencies [Colyvan] |
Full Idea: Those who see probabilities as ratios of frequencies can't use Bayes's Theorem if there is no objective prior probability. Those who accept prior probabilities tend to opt for a subjectivist account, where probabilities are degrees of belief. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 9.1.8) | |
A reaction: [compressed] |
17939 | Mathematics can reveal structural similarities in diverse systems [Colyvan] |
Full Idea: Mathematics can demonstrate structural similarities between systems (e.g. missing population periods and the gaps in the rings of Saturn). | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 6.3.2) | |
A reaction: [Colyvan expounds the details of his two examples] It is these sorts of results that get people enthusiastic about the mathematics embedded in nature. A misunderstanding, I think. |
17938 | Mathematics can show why some surprising events have to occur [Colyvan] |
Full Idea: Mathematics can show that under a broad range of conditions, something initially surprising must occur (e.g. the hexagonal structure of honeycomb). | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 6.3.2) |
17934 | Proof by cases (by 'exhaustion') is said to be unexplanatory [Colyvan] |
Full Idea: Another style of proof often cited as unexplanatory are brute-force methods such as proof by cases (or proof by exhaustion). | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1) |
17933 | Reductio proofs do not seem to be very explanatory [Colyvan] |
Full Idea: One kind of proof that is thought to be unexplanatory is the 'reductio' proof. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1) | |
A reaction: Presumably you generate a contradiction, but are given no indication of why the contradiction has arisen? Tracking back might reveal the source of the problem? Colyvan thinks reductio can be explanatory. |
17935 | If inductive proofs hold because of the structure of natural numbers, they may explain theorems [Colyvan] |
Full Idea: It might be argued that any proof by induction is revealing the explanation of the theorem, namely, that it holds by virtue of the structure of the natural numbers. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.1) | |
A reaction: This is because induction characterises the natural numbers, in the Peano Axioms. |
17942 | Can a proof that no one understands (of the four-colour theorem) really be a proof? [Colyvan] |
Full Idea: The proof of the four-colour theorem raises questions about whether a 'proof' that no one understands is a proof. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 9.1.6) | |
A reaction: The point is that the theorem (that you can colour countries on a map with just four colours) was proved with the help of a computer. |
17937 | Mathematical generalisation is by extending a system, or by abstracting away from it [Colyvan] |
Full Idea: One type of generalisation in mathematics extends a system to go beyond what is was originally set up for; another kind involves abstracting away from some details in order to capture similarities between different systems. | |
From: Mark Colyvan (Introduction to the Philosophy of Mathematics [2012], 5.2.2) |
10630 | Abstracted objects are not mental creations, but depend on equivalence between given entities [Hale/Wright] |
Full Idea: The new kind of abstract objects are not creations of the human mind. ...The existence of such objects depends upon whether or not the relevant equivalence relation holds among the entities of the presupposed kind. | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.2) | |
A reaction: It seems odd that we no longer have any choice about what abstract objects we use, and that we can't evade them if the objects exist, and can't have them if the objects don't exist - and presumably destruction of the objects kills the concept? |
8786 | One first-order abstraction principle is Frege's definition of 'direction' in terms of parallel lines [Hale/Wright] |
Full Idea: An example of a first-order abstraction principle is Frege's definition of 'direction' in terms of parallel lines; a higher-order example (which refers to first-order predicates) defines 'equinumeral' in terms of one-to-one correlation (Hume's Principle). | |
From: B Hale / C Wright (Logicism in the 21st Century [2007], 1) | |
A reaction: [compressed] This is the way modern logicians now treat abstraction, but abstraction principles include the elusive concept of 'equivalence' of entities, which may be no more than that the same adjective ('parallel') can be applied to them. |
12227 | Abstractionism needs existential commitment and uniform truth-conditions [Hale/Wright] |
Full Idea: Abstractionism needs a face-value, existentially committed reading of the terms occurring on the left-hand sides together with sameness of truth-conditions across the biconditional. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §5) | |
A reaction: They employ 'abstractionism' to mean their logical Fregean strategy for defining abstractions, not to mean the older psychological account. Thus the truth-conditions for being 'parallel' and for having the 'same direction' must be consistent. |
12228 | Equivalence abstraction refers to objects otherwise beyond our grasp [Hale/Wright] |
Full Idea: Abstraction principles purport to introduce fundamental means of reference to a range of objects, to which there is accordingly no presumption that we have any prior or independent means of reference. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §8) | |
A reaction: There's the rub! They make it sound like a virtue, that we open up yet another heaven of abstract toys to play with. As fictions, they are indeed exciting new fun. As platonic discoveries they strike me as Cloud-Cuckoo Land. |
12231 | Reference needs truth as well as sense [Hale/Wright] |
Full Idea: It takes, over and above the possession of sense, the truth of relevant contexts to ensure reference. | |
From: B Hale / C Wright (The Metaontology of Abstraction [2009], §9) | |
A reaction: Reference purely through sense was discredited by Kripke. The present idea challenges Kripke's baptismal realist approach. How do you 'baptise' an abstract object? But isn't reference needed prior to the establishment of truth? |
10627 | Many conceptual truths ('yellow is extended') are not analytic, as derived from logic and definitions [Hale/Wright] |
Full Idea: There are many statements which are plausibly viewed as conceptual truths (such as 'what is yellow is extended') which do not qualify as analytic under Frege's definition (as provable using only logical laws and definitions). | |
From: B Hale / C Wright (Intro to 'The Reason's Proper Study' [2001], 3.2) | |
A reaction: Presumably this is because the early assumptions of Frege were mathematical and logical, and he was trying to get away from Kant. That yellow is extended is a truth for non-linguistic beings. |
21181 | Relativity and Quantum theory give very different accounts of forces [Hesketh] |
Full Idea: General Relativity and quantum mechanics are the two great theories in physics today but they give two very different ideas for how forces work. | |
From: Gavin Hesketh (The Particle Zoo [2016], 01) | |
A reaction: Relativity says it is space curvature, and quantum theory says it is particle exchange? But is there a Relativity account of the strong nuclear force? |
21183 | Thermodynamics introduced work and entropy, to understand steam engine efficiency [Hesketh] |
Full Idea: The Laws of Thermodynamics introduced the concepts of entropy and work; put simply, how much useful energy you can really get out of a steam engine. | |
From: Gavin Hesketh (The Particle Zoo [2016], 03) | |
A reaction: The point of science by this stage was to introduce measurable and quantifiable concepts |
21191 | Photons are B and W° bosons, linked by the Higgs mechanism [Hesketh] |
Full Idea: The photon is actually a mix of two deeper things, the B and the W°, tied together by the Higgs mechanism. | |
From: Gavin Hesketh (The Particle Zoo [2016], 06) | |
A reaction: The B (for 'Boson') transmits a force associated with the 'winding symmetry'. (I record this without properly understanding it.) |
21199 | Spinning electric charge produces magnetism, so all fermions are magnets [Hesketh] |
Full Idea: The muon, like all fermions, spins - and because a spinning electric charge generates a magnetic field all fermions act like tiny bar magnets. | |
From: Gavin Hesketh (The Particle Zoo [2016], 11) |
21180 | Electrons are fundamental and are not made of anything; they are properties without size [Hesketh] |
Full Idea: As far as we can tell, electrons (and quarks) are fundamental. They are not small lumps of material, because we could always ask what the material is. The electron just ...is. They are collections of properties, with no apparent size. | |
From: Gavin Hesketh (The Particle Zoo [2016], 01) | |
A reaction: This idea from physics HAS to be of interest to philosophers! The bundle theory is discredited for normal objects and for minds, and so is the substrate idea for supporting properties. But rigorous physics accepts a bundle theory. |
21189 | Electrons may have smaller components, bound by a new force [Hesketh] |
Full Idea: Quarks, leptons or bosons may actually be made up of something even smaller, bound together by a conjectural new force. | |
From: Gavin Hesketh (The Particle Zoo [2016], 05) | |
A reaction: Electrons are a type of lepton. Compare Idea 21180, from the same book. If electrons are not fundamental, what matters is not some 'stuff' they are made of, but a different force that would bind the ingredients. |
21182 | Quantum mechanics is our only theory, and is very precise, and repeatedly confirmed [Hesketh] |
Full Idea: Quantum mechanics is the only working description of the universe that we have. It is amazingly precise, and so far every experimental test has verified its predictions. | |
From: Gavin Hesketh (The Particle Zoo [2016], 02) | |
A reaction: I take it from this that quantum mechanics is simply TRUE. Get over it! It will never turn out to be wrong, but may be subsumed within some more fine-grained or extensive theory. |
21184 | Physics was rewritten to explain stable electron orbits [Hesketh] |
Full Idea: Explaining the stable electron orbits would require a complete rewriting of the physics of subatomic particles. | |
From: Gavin Hesketh (The Particle Zoo [2016], 03) | |
A reaction: This really looks like a simple and major landmark moment. You can ignore a single anomaly, but not a central feature of your entire theory. |
21187 | Virtual particles can't be measured, and can ignore the laws of physics [Hesketh] |
Full Idea: We can never measure these virtual (transitory) particles directly, and it turns out that they don't even have to obey the laws of physics. | |
From: Gavin Hesketh (The Particle Zoo [2016], 05) | |
A reaction: These seems to be the real significance of the Uncertainty Principle. Such particles 'borrow' huge amounts of energy for very short times. |
21185 | Colour charge is positive or negative, and also has red, green or blue direction [Hesketh] |
Full Idea: Colour charge is 'three-dimensional'. As well as the charge having a positive or negative sign, it can also have a direction, and for convenience these three different directions (pointing like a weather vane) are labelled 'red', 'green' and 'blue'. | |
From: Gavin Hesketh (The Particle Zoo [2016], 04) |
21194 | The Standard Model omits gravity, because there are no particles involved [Hesketh] |
Full Idea: Gravity is not included in the Standard Model because we simply cannot study it using particles. | |
From: Gavin Hesketh (The Particle Zoo [2016], 09) | |
A reaction: I'm guessing that Einstein describes how gravity behaves, but not what it is. |
21195 | In Supersymmetry the Standard Model simplifies at high energies [Hesketh] |
Full Idea: Supersymmetry suggest that the Standard Model becomes much simpler at high energies. | |
From: Gavin Hesketh (The Particle Zoo [2016], 10) |
21197 | Standard Model forces are one- two- and three-dimensional [Hesketh] |
Full Idea: The forces in the Standard Model are built on gauge symmetries, with a one-dimensional charge (like electromagnetism), a two-dimensional charge (the weak force), and a three dimensional charge (the strong force). | |
From: Gavin Hesketh (The Particle Zoo [2016], 10) | |
A reaction: See also Idea 21185. |
21188 | Quarks and leptons have a weak charge, for the weak force [Hesketh] |
Full Idea: For the weak force there must be a corresponding 'weak charge', and all the fermions, all the quarks and leptons carry it. | |
From: Gavin Hesketh (The Particle Zoo [2016], 05) | |
A reaction: So electrons carry a weak charge, as well as an electromagnetic charge. Like owning several passports. |
21186 | Quarks rush wildly around in protons, restrained by the gluons [Hesketh] |
Full Idea: Inside a proton the quarks are rushing around like caged animals, free to move until they push against the bars to try to escape, when the gluons pull them back in. | |
From: Gavin Hesketh (The Particle Zoo [2016], 04) |
21192 | Neutrinos only interact with the weak force, but decays produce them in huge numbers [Hesketh] |
Full Idea: Neutrinos only interact with the weak force, which means they barely interact at all, but because the weak force is crucial in the decays of so many other particles, neutrinos are still produced in huge numbers. | |
From: Gavin Hesketh (The Particle Zoo [2016], 08) | |
A reaction: They only interact with the W and Z bosons. |
21196 | To combine the forces, they must all be the same strength at some point [Hesketh] |
Full Idea: If all the forces are to combine, at some point they must all be the same strength, and Supersymmetry (SuSy) makes this happen. | |
From: Gavin Hesketh (The Particle Zoo [2016], 10) | |
A reaction: This sounds like an impressive reason for favouring supersymmetry - as long as you have an a priori preference for everything combining. |
21190 | 'Space' in physics just means location [Hesketh] |
Full Idea: 'Space' in physics really just means location. | |
From: Gavin Hesketh (The Particle Zoo [2016], 06) | |
A reaction: Location can, of course, only be specified relative to something else. Space is really an abstraction, but at least it means there is some sort of background to locate all the fundamental fields. |
21193 | The universe is 68% dark energy, 27% dark matter, 5% regular matter [Hesketh] |
Full Idea: The most precise surveys of the stars and galaxies tell us that the universe is made up of 68% dark energy, 27% dark matter, and just 5% regular matter (the stuff of the Standard Model of particle physics). | |
From: Gavin Hesketh (The Particle Zoo [2016], 09) | |
A reaction: Regular matter - that's me, that is. |
21198 | If a cosmic theory relies a great deal on fine-tuning basic values, it is probably wrong [Hesketh] |
Full Idea: If a theory has to rely on excessive 'fine-tuning', a series of extremely unlikely events in order to produce the universe we see around us, then it is extremely unlikely that this theory is correct. | |
From: Gavin Hesketh (The Particle Zoo [2016], 10) | |
A reaction: He says the Standard Model has 26 parameters which are only known by experiment, rather than by theory. So instead of saying '...so there is a God', we should say '...so our theory isn't very good'. |