75 ideas
| 21887 | Derrida focuses on other philosophers, rather than on science [Derrida] |
| Full Idea: We should focus on other philosophers, and not on science. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21888 | Philosophy is just a linguistic display [Derrida] |
| Full Idea: Philosophy is entirely linguistic, and is a display. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21896 | Philosophy aims to build foundations for thought [Derrida, by May] |
| Full Idea: Derrida points out that the project of philosophy consists largely in attempting to build foundations for thought. | |
| From: report of Jacques Derrida (works [1990]) by Todd May - Gilles Deleuze 1.04 | |
| A reaction: You would first need to be convinced that there could be such a thing as foundations for thinking. Derrida thinks the project is hopeless. I think of it more as building an ideal framework for thought. |
| 21893 | Philosophy is necessarily metaphorical, and its writing is aesthetic [Derrida] |
| Full Idea: All of philosophy is necessarily metaphorical, and hence aesthetic. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21892 | Interpretations can be interpreted, so there is no original 'meaning' available [Derrida] |
| Full Idea: Because interpretations of texts can be interpreted, they can therefore have no 'original meaning'. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 20925 | Hermeneutics blunts truth, by conforming it to the interpreter [Derrida, by Zimmermann,J] |
| Full Idea: Derrida worried that hermeneutics blunts the disruptive power of truth by forcing it conform to the interpreter's mental horizon. | |
| From: report of Jacques Derrida (works [1990]) by Jens Zimmermann - Hermeneutics: a very short introduction 3 'The heart' | |
| A reaction: Good heavens - I agree with Derrida. Very French, though, to see the value of truth in its disruptiveness. I tend to find the truth reassuring, but then I'm English. |
| 20934 | Hermeneutics is hostile, trying to overcome the other person's difference [Derrida, by Zimmermann,J] |
| Full Idea: Derrida described the hermeneutic impulse to understand another as a form of violence that seeks to overcome the other's particularity and unique difference. | |
| From: report of Jacques Derrida (works [1990]) by Jens Zimmermann - Hermeneutics: a very short introduction App 'Derrida' | |
| A reaction: I'm not sure about 'violence', but Derrida was on to somethng here. The 'hermeneutic circle' sounds like a creepy process of absorption, where the original writer disappears in a whirlpool of interpretation. |
| 21895 | Structuralism destroys awareness of dynamic meaning [Derrida] |
| Full Idea: Structuralism destroys awareness of dynamic meaning. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21934 | The idea of being as persistent presence, and meaning as conscious intelligibility, are self-destructive [Derrida, by Glendinning] |
| Full Idea: The tradition of conceiving being in terms of persisting presence, and meaning in terms of pure intelligibility or logos potentially present to the mind, finds itself dismantled by resources internal to its own construction. | |
| From: report of Jacques Derrida (works [1990]) by Simon Glendinning - Derrida: A Very Short Introduction 6 | |
| A reaction: [compressed] Glendinning says this is the basic meaning of de-construction. My personal reading of this is that Aristotle is right, and grand talk of Being is hopeless, so we should just aim to understand objects. I also believe in propositions. |
| 21883 | Sincerity can't be verified, so fiction infuses speech, and hence reality also [Derrida] |
| Full Idea: Sincerity can never be verified, so fiction infuses all speech, which means that reality is also fictional. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21882 | Sentences are contradictory, as they have opposite meanings in some contexts [Derrida] |
| Full Idea: Sentences are implicitly contradictory, because they can be used differently in different contexts (most obviously in 'I am ill'). | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21881 | We aim to explore the limits of expression (as in Mallarmé's poetry) [Derrida] |
| Full Idea: The aim is to explore the limits of expression (which is what makes the poetry of Mallarmé so important). | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 15787 | Maybe Ockham's Razor is a purely aesthetic principle [Lycan] |
| Full Idea: It might be said that Ockham's Razor is a purely aesthetic principle. | |
| From: William Lycan (The Trouble with Possible Worlds [1979], 02) | |
| A reaction: I don't buy this, if it meant to be dismissive of the relevance of the principle to truth. A deep question might be, what is so aesthetically attractive about simplicity? I'm inclined to think that application of the Razor has delivered terrific results. |
| 15784 | The Razor seems irrelevant for Meinongians, who allow absolutely everything to exist [Lycan] |
| Full Idea: A Meinongian has already posited everything that could, or even could not, be; how, then, can any subsequent brandishing of Ockham's Razor be to the point? | |
| From: William Lycan (The Trouble with Possible Worlds [1979], 02) | |
| A reaction: See the ideas of Alexius Meinong. Presumably these crazy Meinongians must make some distinction between what actually exists in front of your nose, and the rest. So the Razor can use that distinction too. |
| 4756 | Derrida says that all truth-talk is merely metaphor [Derrida, by Engel] |
| Full Idea: Derrida's view is that every discourse is metaphorical, and there is no difference between truth-talk and metaphor. | |
| From: report of Jacques Derrida (works [1990]) by Pascal Engel - Truth §2.5 | |
| A reaction: Right. Note that this is a Frenchman's summary. How would one define metaphor, without mentioning that it is parasitic on truth? Certainly some language tries to be metaphor, and other language tries not to be. |
| 21877 | True thoughts are inaccessible, in the subconscious, prior to speech or writing [Derrida] |
| Full Idea: 'True' thoughts are inaccessible, buried in the subconscious, long before they get to speech or writing. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction | |
| A reaction: [My reading of some Derrida produced no quotations. I've read two commentaries, which were obscure. The Derrida ideas in this db are my simplistic tertiary summaries. Experts can chuckle over my failure] |
| 21889 | 'I' is the perfect name, because it denotes without description [Derrida] |
| Full Idea: 'I' is the perfect name, because it denotes without description. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21878 | Names have a subjective aspect, especially the role of our own name [Derrida] |
| Full Idea: We can give a subjective account of names, by considering our own name. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21879 | Even Kripke can't explain names; the word is the thing, and the thing is the word [Derrida] |
| Full Idea: Even Kripke can't explain names, because the word is the thing, and also the thing is the word. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 15792 | Maybe non-existent objects are sets of properties [Lycan] |
| Full Idea: Meinong's Objects have sometimes been construed as sets of properties. | |
| From: William Lycan (The Trouble with Possible Worlds [1979], 09) | |
| A reaction: [Lycan cites Castañeda and T.Parsons] You still seem to have the problem with any 'bundle' theory of anything. A non-existent object is as much intended to be an object as anything on my desk right now. It just fails to be. |
| 15795 | Treating possible worlds as mental needs more actual mental events [Lycan] |
| Full Idea: A mentalistic approach to possible worlds is daunted by the paucity of actual mental events. | |
| From: William Lycan (The Trouble with Possible Worlds [1979], 09) | |
| A reaction: Why do they have to be actual, any more than memories have to be conscious? The mental events just need to be available when you need them. They are never all required simultaneously. This isn't mathematical logic! |
| 15796 | Possible worlds must be made of intensional objects like propositions or properties [Lycan] |
| Full Idea: I believe the only promising choice of actual entities to serve as 'worlds' is that of sets of intensional objects, such as propositions or properties with stipulated interrelations. | |
| From: William Lycan (The Trouble with Possible Worlds [1979], 12) | |
| A reaction: This is mainly in response to Lewis's construction of them out of actual concrete objects. It strikes me as a bogus problem. It is just a convenient way to think precisely about possibilities, and occasionally outruns our mental capacity. |
| 15794 | If 'worlds' are sentences, and possibility their consistency, consistency may rely on possibility [Lycan] |
| Full Idea: If a 'world' is understood as a set of sentences, then possibility may be understood as consistency, ...but this seems circular, in that 'consistency' of sentences cannot adequately be defined save in terms of possibility. | |
| From: William Lycan (The Trouble with Possible Worlds [1979], 09) | |
| A reaction: [Carnap and Hintikka propose the view, Lewis 'Counterfactuals' p.85 objects] Worlds as sentences is not, of course, the same as worlds as propositions. There is a lot of circularity around in 'possible' worlds. |
| 21890 | Heidegger showed that passing time is the key to consciousness [Derrida] |
| Full Idea: Heidegger showed us the importance of transient time for consciousness. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21880 | 'Tacit theory' controls our thinking (which is why Freud is important) [Derrida] |
| Full Idea: All thought is controlled by tacit theory (which is why Freud is so important). | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction | |
| A reaction: This idea is said to be the essential thought of Derrida's Deconstruction. The aim is liberation of thought, by identifying and bypassing these tacit metaphysical schemas. |
| 21886 | Meanings depend on differences and contrasts [Derrida] |
| Full Idea: Meaning depends on 'differences' (contrasts). | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21930 | For Aristotle all proper nouns must have a single sense, which is the purpose of language [Derrida] |
| Full Idea: A noun [for Aristotle] is proper when it has but a single sense. Better, it is only in this case that it is properly a noun. Univocity is the essence, or better, the telos of language. | |
| From: Jacques Derrida (works [1990]), quoted by Simon Glendinning - Derrida: A Very Short Introduction 5 | |
| A reaction: [no ref given] His target seem to be Aristotelian definition, and also formal logic, which usually needs unambiguous meanings. {I'm puzzled that he thinks 'telos' is simply better than 'essence', since it is quite different]. |
| 21884 | Capacity for repetitions is the hallmark of language [Derrida] |
| Full Idea: The capacity for repetitions is the hallmark of language. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21935 | The sign is only conceivable as a movement between elusive presences [Derrida] |
| Full Idea: The sign is conceivable only on the basis of the presence that it defers, and moving toward the deferred presence that it aims to reappropriate. | |
| From: Jacques Derrida (works [1990]), quoted by Simon Glendinning - Derrida: A Very Short Introduction 6 | |
| A reaction: [Glendinning gives no source for this] I take the fundamental idea to be that meanings are dynamic, when they are traditionally understood as static (and specifiable in dictionaries). |
| 21933 | Writing functions even if the sender or the receiver are absent [Derrida, by Glendinning] |
| Full Idea: Writing can and must be able to do without the presence of the sender. ...Also writing can and must he able to do without the presence of the receiver. | |
| From: report of Jacques Derrida (works [1990]) by Simon Glendinning - Derrida: A Very Short Introduction 6 | |
| A reaction: In simple terms, one of them could die during the transmission. This is the grounds for the assertion of the primacy of writing. It opposes orthodox views which define language in terms of sender and receiver. |
| 21894 | Madness and instability ('the demonic hyperbole') lurks in all language [Derrida] |
| Full Idea: Madness and instability ('the demonic hyperbole') lurks behind all language. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21931 | 'Dissemination' is opposed to polysemia, since that is irreducible, because of multiple understandings [Derrida, by Glendinning] |
| Full Idea: The intention to oppose polysemia with dissemination does not aim to affirm that everything we say is ambiguous, but that polysemia is irreducible in the sense that each and every 'meaning' is itself subject to more than one understanding. | |
| From: report of Jacques Derrida (works [1990]) by Simon Glendinning - Derrida: A Very Short Introduction 5 | |
| A reaction: The key point, I think, is that ambiguity and polysemia are not failures of language (which is the way most logicians see it), but part of the essential and irreducible nature of language. Nietzsche started this line of thought. |
| 21885 | Words exist in 'spacing', so meanings are never synchronic except in writing [Derrida] |
| Full Idea: Words only exist is 'spacings' (of time and space), so there are no synchronic meanings (except perhaps in writing). | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21891 | The good is implicitly violent (against evil), so there is no pure good [Derrida] |
| Full Idea: Even the good is implicitly violent (against evil), so there can be no 'pure' good. | |
| From: Jacques Derrida (works [1990]), quoted by Barry Stocker - Derrida on Deconstruction |
| 21167 | Gravity is unusual, in that it always attracts and never repels [New Sci.] |
| Full Idea: Gravity is an odd sort of force, not least because it only ever works one way. Electromagnetism attracts and repels, but with gravity there are only positive masses always attract. | |
| From: New Scientist writers (Why the Universe Exists [2017], 05) | |
| A reaction: This leads to speculation about anti-gravity, but there is no current evidence for it. |
| 21176 | In the Big Bang general relativity fails, because gravity is too powerful [New Sci.] |
| Full Idea: At the origin of the universe gravity becomes so powerful that general relativity breaks down, giving infinity for every answer. | |
| From: New Scientist writers (Why the Universe Exists [2017], 09) |
| 21147 | Quantum electrodynamics incorporates special relativity and quantum mechanics [New Sci.] |
| Full Idea: The theory of electromagnetism that incorporates both special relativity and quantum mechanics is quantum electrodynamics (QED). It was developed by Dirac and others, and perfected in the 1940s. The field is a collection of quanta. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: This builds on Maxwell's earlier classical theory. QED is said to be the best theory in all of physics. |
| 21155 | Photons have zero rest mass, so virtual photons have infinite range [New Sci.] |
| Full Idea: Photons, the field quanta of the electromagnetic force, have zero rest mass, so virtual photons can exist indefinitely and travel any distance, meaning the electromagnetic force has an infinite range. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) |
| 21161 | In the standard model all the fundamental force fields merge at extremely high energies [New Sci.] |
| Full Idea: The standard model says that the fields of all fundamental forces should merge at extremely high energies, meaning there is also a unified, high-energy field out there. | |
| From: New Scientist writers (Why the Universe Exists [2017], 03) | |
| A reaction: Not quite sure what 'out there' means. This idea is linked to the quest for dark energy. Is this unified phenomenon only found near the Big Bang? |
| 21146 | Electrons move fast, so are subject to special relativity [New Sci.] |
| Full Idea: Electrons in atoms move at high speeds, so they are subject to the special theory of relativity. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: Presumably this implies a frame of reference, and defining velocities relative to other electrons. Plus time-dilation? |
| 21148 | The strong force is repulsive at short distances, strong at medium, and fades at long [New Sci.] |
| Full Idea: Experiments show that the nuclear binding force does not follow the inverse square law, but is repulsive at the shortest distances, then attractive, then fades away rapidly as distance increases further. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: So how does it know when to be strong? Magnetism doesn't vary according to distance, and light obeys the inverse square law, because everything is decided at the output. - See 21151 for an explanation. It interacts after departure. |
| 21151 | Gluons, the particles carrying the strong force, interact because of their colour charge [New Sci.] |
| Full Idea: In QCD the particles that carry the strong force are called gluons. ...Gluons carry their own colour charges, so they can interact with each other (unlike photons) via the strong nuclear force (which limits the range of the force). | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: So the force varies in strength with distance because the degree of separation among the spreading gluons varies? The force has one range, which is squashed when close, effective at medium, and loses touch with distance? |
| 21152 | The strong force binds quarks tight, and the nucleus more weakly [New Sci.] |
| Full Idea: The strong force holds quarks together within protons and neutrons, and residual effects of the strong force bind protons (whch repel one another) and neutrons together in nuclei. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: So the force is much stronger between quarks (which can't escape), and only 'residual' in the nucleus, which must be why smashing nuclei open is fairly easy, but smashin protons open needs higher energies. |
| 21142 | Classifying hadrons revealed two symmetry patterns, produced by three basic elements [New Sci.] |
| Full Idea: Classifying hadrons according to charge, strangeness and spin revealed patterns of eight and ten particles (SU(3) symmetery). The mathematics then showed that these are built from a basic group of only three members. | |
| From: New Scientist writers (Why the Universe Exists [2017], 01) |
| 21150 | Three different colours of quark (as in the proton) can cancel out to give no colour [New Sci.] |
| Full Idea: Just as mixing three colours of light gives white, so the three colour charges of quarks can add up to give no colour. This is what happens in the proton, which always contains one blue-charge quark, one red and one green. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) |
| 21143 | Quarks in threes can build hadrons with spin ½ or with spin 3/2 [New Sci.] |
| Full Idea: Quarks in threes can build hadrons with spin ½ (proton, duu; neutron, ddu; lambda, dus), or with spin 3/2 (omega-minus, sss). | |
| From: New Scientist writers (Why the Universe Exists [2017], 01) |
| 21145 | The four fundamental forces (gravity, electromagnetism, weak and strong) are the effects of particles [New Sci.] |
| Full Idea: There are four fundamental forces: gravity, electromagnetism, and the weak and strong nuclear forces. Particle physics has so far failed to encompass the force of gravity. The forces that shape our world are themselves the effect of particles. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: Philosophers must take note of the fact that forces are the effects of particles. Common sense pictures forces imposed on particles, like throwing a tennis ball, but the particles are actually the sources of force. The gravitino is speculative. |
| 21153 | The weak force explains beta decay, and the change of type by quarks and leptons [New Sci.] |
| Full Idea: The beta decay of the neutron (into a proton, an electron and an antineutrino) can be described in terms of the weak force, which is 10,000 times weaker than the strong force. It allows the quarks and leptons to change from one type to another. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: This seems to make it the key source of radioactivity. Perhaps it should be called the Force of Change? |
| 21154 | Three particles enable the weak force: W+ and W- are charged, and Z° is not [New Sci.] |
| Full Idea: The quantum field theory of the weak force needs three carrier particles. The W+ and W- are electrically charged, and enable the weak force to change the charge of a particle. The Z° is uncharged, and mediates weak interactions with no charge change. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) |
| 21156 | The weak force particles are heavy, so the force has a short range [New Sci.] |
| Full Idea: The W and Z particles are heavy, and so cannot travel far from their parents. The weak force therefore has a very short range. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) |
| 21164 | Why do the charges of the very different proton and electron perfectly match up? [New Sci.] |
| Full Idea: Why do the proton and electron charges mirror each other so perfectly when they are such different particles? | |
| From: New Scientist writers (Why the Universe Exists [2017], 04) | |
| A reaction: We seem to have reached a common stage in science, where we have a wonderful descriptive model (the Standard Model), but we cannot explain why what is modelled is the way it is. |
| 21170 | The Standard Model cannot explain dark energy, survival of matter, gravity, or force strength [New Sci.] |
| Full Idea: The standard model cannot explain dark matter, or dark energy (which is causing expansion to accelerate). It cannot explain how matter survived annihilation with anti-matter in the Big Bang, or explain gravity. The strength of each force is unexplained. | |
| From: New Scientist writers (Why the Universe Exists [2017], 06) | |
| A reaction: [compressed] P.141 adds that the model has to be manipulated to keep the Higgs mass low enough. |
| 21140 | Spin is a built-in ration of angular momentum [New Sci.] |
| Full Idea: Spin is a built-in ration of angular momentum. | |
| From: New Scientist writers (Why the Universe Exists [2017], 01) | |
| A reaction: As an outsider all I can do is collect descriptions of such properties from the experts. The experts appear to be happy with the numbers inserted in the equations. |
| 21149 | Quarks have red, green or blue colour charge (akin to electric charge) [New Sci.] |
| Full Idea: Quarks have a property akin to electric charge, called their colour charge. It comes in three varieties, red, green and blue. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) |
| 21158 | Fermions, with spin ½, are antisocial, and cannot share quantum states [New Sci.] |
| Full Idea: Particles with half-integer spin, such as electrons, protons or quarks (all spin ½) have an asymmetry in their wavefunction that makes them antisocial. These particles (Fermions) cannot share a quantum state. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: This is said to explain the complexity of matter, with carbon an especially good example. |
| 21165 | Spin is akin to rotation, and is easily measured in a magnetic field [New Sci.] |
| Full Idea: Spin is a quantum-mechanical property of a particle akin to rotation about its own axis. Particles of different spins respond to magnetic fields in different ways, so it is a relatively easy thing to measure. | |
| From: New Scientist writers (Why the Universe Exists [2017], 04) | |
| A reaction: I wish I knew what 'akin to' meant. Maybe particles are not rigid bodies, so they cannot spin in the way a top can? It must be an electro-magnetic property. Idea 21166 says spin has two possible directions. |
| 21157 | Particles are spread out, with wave-like properties, and higher energy shortens the wavelength [New Sci.] |
| Full Idea: Particles obeying the laws of quantum mechanics have wave-like properties - moving as a quantum wave-function, spread out in space, with wavelengths that get shorter as their energy increases. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: Thus X-rays are dangerous, but long wave radio is not. De Broglie's equation. |
| 21163 | The mass of protons and neutrinos is mostly binding energy, not the quarks [New Sci.] |
| Full Idea: Most of a proton's or neutrino's mass is contained in the interaction energies of a 'sea' of quarks, antiquarks and gluons that bind them. ...You might feel solid, but in fact you're 99 per cent binding energy. | |
| From: New Scientist writers (Why the Universe Exists [2017], 04) | |
| A reaction: This is because energy is equivalent to mass (although gluons are said to have energy but no mass - puzzled by that). This is a fact which needs a bit of time to digest. Once you've grasped we are full of space, you still have understood it. |
| 21168 | Gravitional mass turns out to be the same as inertial mass [New Sci.] |
| Full Idea: There are two types of mass: gravitational mass quantifies how strongly an object feels gravity, while inertial mass quantifies an object's resistance to acceleration. There proven equality is at the heart of General Relativity. | |
| From: New Scientist writers (Why the Universe Exists [2017], 05) | |
| A reaction: It had never occurred to me that these two values might come apart. Doesn't their identical values demonstrate that they are in fact the same thing? Sounds like Hesperus/Phosphorus to me. The book calls it 'mysterious'. |
| 21138 | Neutrons are slightly heavier than protons, and decay into them by emitting an electron [New Sci.] |
| Full Idea: The proton (938.3 MeV) is lighter than the neutron (939.6 MeV) and does not decay, but the heavier neutron can change into a proton by emitting an electron. (If you gather a bucketful of neutrons, after ten minutes only half of them would be left). | |
| From: New Scientist writers (Why the Universe Exists [2017], 01) | |
| A reaction: Protons are more or less eternal, but some theories have them decaying after billions of years. Smashing protons together is a popular pastime for physicists. |
| 21144 | Top, bottom, charm and strange quarks quickly decay into up and down [New Sci.] |
| Full Idea: Quarks can change from one variety to another, and the top, bottom, charm and strange quarks all rapidly decay to the up and down quarks of everyday life. | |
| From: New Scientist writers (Why the Universe Exists [2017], 01) | |
| A reaction: Hence the universe is largely composed of up and down quarks and electrons. The other quarks seem to be more important in the early universe. |
| 21141 | Neutrinos were proposed as the missing energy in neutron beta decay [New Sci.] |
| Full Idea: When a neutron decays into a proton and an electron (one example of beta decay), the energy of the two particles adds up to less than the starting energy of the neutron. Pauli and Fermi concluded that a neutrino (an electron antineutrino) is emitted. | |
| From: New Scientist writers (Why the Universe Exists [2017], 01) | |
| A reaction: I'm wondering how much they could infer about the nature of the new particle (which was only confirmed 26 years later). |
| 21169 | Only neutrinos spin anticlockwise [New Sci.] |
| Full Idea: Neutrinos are the only particles that seem just to spin anticlockwise. | |
| From: New Scientist writers (Why the Universe Exists [2017], 06) | |
| A reaction: See 21166. Anti-neutrino spin is the opposite way. Which way up do you hold the neutrino when pronouncing that it is 'anticlockwise? |
| 21166 | Standard antineutrinos have opposite spin and opposite lepton number [New Sci.] |
| Full Idea: In the conventional standard model neutrinos have antiparticles - which spin in the opposite direction, and have the opposite lepton number. | |
| From: New Scientist writers (Why the Universe Exists [2017], 05) |
| 21171 | The symmetry of unified electromagnetic and weak forces was broken by the Higgs field [New Sci.] |
| Full Idea: In the very early hot universe the electromagnetic and weak nuclear forces were one. The early emergence of the Higgs field led to electroweak symmetry breaking. The W and Z bosons grew fat, and the photon raced away mass-free. | |
| From: New Scientist writers (Why the Universe Exists [2017], 07) |
| 21178 | String theory is now part of 11-dimensional M-Theory, involving p-branes [New Sci.] |
| Full Idea: String theory has now been incorporated into Ed Witten's M-Theory, which is a mathematical framework that lives in 11-dimensional space-time, involving higher-dimensional objects called p-branes, of which strings are a special case. | |
| From: New Scientist writers (Why the Universe Exists [2017], 09) |
| 21179 | Supersymmetric string theory can be expressed using loop quantum gravity [New Sci.] |
| Full Idea: String theory, together with its supersymmetric particles, has recently been rewritten in the space-time described by loop quantum gravity (which says that space-time ust be made from finite chunks). | |
| From: New Scientist writers (Why the Universe Exists [2017], 09) |
| 21175 | String theory might be tested by colliding strings to make bigger 'stringballs' [New Sci.] |
| Full Idea: A future accelerator might create 'stringballs', when two strings slam into one another and, rather than combining to form a stretched string, make a tangled ball. Finding them would prove string theory. | |
| From: New Scientist writers (Why the Universe Exists [2017], 08) | |
| A reaction: This is the only possible test for string theory which I have seen suggested. How do you 'slam strings together'? |
| 21177 | String theory offers a quantum theory of gravity, by describing the graviton [New Sci.] |
| Full Idea: String theory works as a quantum theory of gravity because string vibrations can describe gravitons, the hypothetical carriers of the gravitational force. | |
| From: New Scientist writers (Why the Universe Exists [2017], 09) | |
| A reaction: Presumably the main aim of a quantum theory of gravity is to include gravitons within particle theory. This idea has to be a main attraction of string theory. Compare Idea 21166. |
| 21162 | Only supersymmetry offers to incorporate gravity into the scheme [New Sci.] |
| Full Idea: Peter Higgs says he is a fan of supersymmetry, largely because it seems to be the only route by which gravity can be brought into the scheme. | |
| From: New Scientist writers (Why the Universe Exists [2017], 03) | |
| A reaction: Peter Higgs proposed the Higgs boson (now discovered). This seems a very good reason to favour supersymmetry. A grand unified theory that left out gravity doesn't seem to be unified quite grandly enough. |
| 21159 | Supersymmetry has extra heavy bosons and heavy fermions [New Sci.] |
| Full Idea: Supersymmetry posits heavy boson partners for all fermions, and heavy fermions for all bosons. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: The main Fermions are electron, proton and quark. Do extra bosons imply extra forces? Peter Higgs favours supersymmetry. |
| 21173 | Supersymmetry says particles and superpartners were unities, but then split [New Sci.] |
| Full Idea: The key to supersymmetry is that in the high-energy soup of the early universe, particles and their superpartners were indistinguishable. Each pair existed as single massless entities. With expansion and cooling this supersymmetry broke down. | |
| From: New Scientist writers (Why the Universe Exists [2017], 08) |
| 21172 | The evidence for supersymmetry keeps failing to appear [New Sci.] |
| Full Idea: The old front-runner theory, supersymmetry, has fallen from grace as the Large Hadron Collider keeps failing to find it. | |
| From: New Scientist writers (Why the Universe Exists [2017], 07) |
| 21160 | The Higgs field means even low energy space is not empty [New Sci.] |
| Full Idea: The point about the Higgs field is that even the lowest-energy state of space is not empty. | |
| From: New Scientist writers (Why the Universe Exists [2017], 02) | |
| A reaction: So where is the Higgs field located? Even if there is no utterly empty space, the concept of location implies a concept of space more basic than the fields (about 16, I gather) which occupy it. You can't describe movement without a concept of location. |
| 21174 | Dark matter must have mass, to produce gravity, and no electric charge, to not reflect light [New Sci.] |
| Full Idea: Whatever dark matter is made of, it must have mass to feel and generate gravity; but no electric charge, so it does not interact with light. The leading candidate has been the weakly interacting massive particle (WIMP), much heavier than a proton. | |
| From: New Scientist writers (Why the Universe Exists [2017], 08) | |
| A reaction: Note that it must 'generate' gravity. The idea of a law of gravity which is externally imposed on matter is long dead. Heavy WIMPs have not yet been detected. |