100 ideas
| 22611 | Metaphysics can criticise interpretations of science theories, and give good feedback [Ingthorsson] |
| Full Idea: Metaphysics is capable of critical scrutiny of the way the empirical sciences make sense of their own theories, and can provide them with very useful feedback. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1.9) | |
| A reaction: I agree with this, but I don't think it is the main job of metaphysics, which has its own agenda, using science as some of its raw material. |
| 22609 | Philosophers accepted first-order logic, because they took science to be descriptive, not explanatory [Ingthorsson] |
| Full Idea: First-order predicate logic was accepted so easily by the philosophical community …because philosophy was already geared toward a neo-Humean view of both science and philosophy as primarily descriptive rather than explanatory. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1.8) | |
| A reaction: The point, I think, is that explanatory thinking needs second-order logic, where the properties (or powers) are players in the game, and not just adjuncts of the catalogue of objects. I find this idea mind-expanding. (That's a good thing). |
| 19482 | Current physics says matter and antimatter should have reduced to light at the big bang [New Sci.] |
| Full Idea: Our best theories of physics imply we shouldn't be here. The big bang ought to have produced equal amounts of matter and antimatter particles, which would have almost immediately annihilated each other, leaving nothing but light. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.05.23) | |
| A reaction: This is not, of course, a rejection of physics, but a puzzle about the current standard model of physics. |
| 19483 | CP violation shows a decay imbalance in matter and antimatter, leading to matter's dominance [New Sci.] |
| Full Idea: The phenomenon of charge-parity (CP) violation says that under certain circumstances antiparticles decay at different rates from their matter counterpart. ...This might explain matter's dominance in the universe, but the effect is too small. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.05.23) | |
| A reaction: Physicists are currently studying CP violations, hoping to explain why there is any matter in the universe. This will not, I presume, explain why matter and antimatter arrived in the first place. |
| 22629 | Basic processes are said to be either physical, or organic, or psychological [Ingthorsson] |
| Full Idea: Process philosophy is considered to include ideas of process as basically physical (Whitehead 1929), as basically organic (Bergson 1910), and as basically psychological (James 1890). | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 7.4) | |
| A reaction: I take Whitehead to be the only serious contender here. |
| 22633 | Indirect realists are cautious about the manifest image, and prefer the scientific image [Ingthorsson] |
| Full Idea: The indirect realist regards the manifest image with scepticism and contrasts it to the scientific image. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 8.13) | |
| A reaction: This is why indirect realism is the best view for a realist who largely accepts the authority of science, Philosophers can wallow in the manifest image all they like (and most of them seem to love it), but truth is in the scientific image. |
| 22606 | Neo-Humeans say there are no substantial connections between anything [Ingthorsson] |
| Full Idea: Neo-Humean metaphysics holds the view that there are no substantial connections between anything in this world. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1) | |
| A reaction: A very illuminating comment. This exactly fits Lewis's great 'mosaic' of facts. The challenge is to say what 'substantial' relations there might be, but I'm quite happy to have a go at that. |
| 22631 | Properties are said to be categorical qualities or non-qualitative dispositions [Ingthorsson] |
| Full Idea: It is said that that properties divide into two mutually exclusive types—non-dispositional qualities (sometimes called 'categorical properties’) vs. non-qualitative dispositions—of which the qualities are more fundamental than dispositions. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 8) | |
| A reaction: It is standardly understood that the qualitative categorical properties are more fundamental. Fans of powers (such as Ingthorsson and myself) either favour the dispositional properties, or reject the distinction. |
| 22632 | Physics understands the charge of an electron as a power, not as a quality [Ingthorsson] |
| Full Idea: Is the negative charge of an electron a quality or power? It is clear that physics describes the nature of charge only in terms of what its bearer can do. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 8.06) | |
| A reaction: The point is that an electron has properties, even though it has no observable qualities. Ingthorsson says the scientific concept of qualities is entirely about what something can do, and ot how it is perceived. |
| 22627 | Compound objects are processes, insofar as change is essential to them [Ingthorsson] |
| Full Idea: Compound objects are to be considered processes, if by ‘process’ we mean any entity for which change is essential for its continued existence. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 7) | |
| A reaction: This doesn't seem to matter much, except to challenge those who say that reality consists of processes, and therefore not of substances. |
| 22613 | Most materialist views postulate smallest indivisible components which are permanent [Ingthorsson] |
| Full Idea: Most materialist ontologies of the past postulate that the world ultimately consists of smallest indivisible component parts that persist because they must; they are permanent. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 2.1) | |
| A reaction: Van Inwagen is notable for this view. Ingthorsson says the theory is to explain medium-sized change, while denying that anything comes to be out of nothing. Theology may lurk in the background. Simple persistance won't explain compound persistance. |
| 22612 | Endurance and perdurance just show the consequences of A or B series time [Ingthorsson] |
| Full Idea: Endurance and perdurance are not explanations, but are merely characterisations of persistance with the constraints imposed by either an A or a B view of time. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 2.1) | |
| A reaction: This is 3-D asnd 4-D objects. A simple and illuminating observation. I love reading broad brush books that make all these simple connections between what seem isolated theories in philosophy. These links are the heart of the subject. |
| 22625 | Science suggests causal aspects of the constitution and persistance of objects [Ingthorsson] |
| Full Idea: There are very obvious causal aspects to the constitution and continued existence of compound entities, especially in light of the scientific image of the world. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 6) | |
| A reaction: I like this a lot. He aims to explain constitution and persistance, rather than just describing or characterising them, and causal binding seems the obvious thought. There are still intermittent and distributed objects, like a dismantled clock. |
| 22620 | If causation involves production, that needs persisting objects [Ingthorsson] |
| Full Idea: If causation involves production, then things must endure rather than perdure, because perdurance is incompatible with production, if creation ex nihilo is ruled out. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 4.10) | |
| A reaction: That is, objects must persist over time. Cannot an account of production be given in terms of time-sliceS (or whatever)? 3-D perdurantists obviously have an account of change. He says it also needs the A-series view of time. |
| 22636 | Every philosophical theory must be true in some possible world, so the ontology is hopeless [Ingthorsson] |
| Full Idea: Possible worlds ontology appears to be plentiful enough to allow every philosophical theory to be true in some world or other, and that is why I cannot consider it an ontologically serious theory. It admits everything and forbids nothing | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 9.6) | |
| A reaction: Nice. Be careful what you wish for. The theory would have to be consistent (unless we also accept impossible worlds). |
| 22638 | Worlds may differ in various respects, but no overall similarity of worlds is implied [Ingthorsson] |
| Full Idea: Even if possible worlds could differ in many different respects, there is no useful way to combine these different respects into one measure of overall comparative similarity. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 9.7) | |
| A reaction: [idea of Michael Moreau 2010] This is an objection to the use of 'close' possible worlds in causation theories. The idea is true in general of the concept of similarity. It makes sense of specific 'respects', but not really of two whole objects. |
| 3061 | Anaxarchus said that he was not even sure that he knew nothing [Anaxarchus, by Diog. Laertius] |
| Full Idea: Anaxarchus said that he was not even sure that he knew nothing. | |
| From: report of Anaxarchus (fragments/reports [c.340 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 09.10.1 |
| 19737 | A system can infer the structure of the world by making predictions about it [New Sci.] |
| Full Idea: If we can train a system for prediction, it can essentially infer the structure of the world it's looking at by doing this prediction. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.12.12) | |
| A reaction: [AI expert] This seems to be powerful support for the centrality of mathematical laws of nature in achieving understanding of the world. We may downplay the 'mere' ability to predict, but this idea says that the rewards of prediction are very great. |
| 19736 | Neural networks can extract the car-ness of a car, or the chair-ness of a chair [New Sci.] |
| Full Idea: Early neural nets were really good at recognising general categories, such as a car or a chair. Those networks are good at extracting the 'chair-ness' or the 'car-ness' of the object. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.12.12) | |
| A reaction: [Interview with Yann LeCun, Facebook AI director] Fregean philosophers such as Geach think that extracting features is a ridiculous idea, but if even a machine can do it then I suspect that human beings can (and do) manage it too. |
| 16419 | No one has yet devised a rationality test [New Sci.] |
| Full Idea: The financial sector has been clamouring for a rationality test for years. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.10.29) | |
| A reaction: Many aspects of intelligence tests do actually pick out what I would call rationality (which includes 'rational intuition', a new favourite of mine). But they are mixed in with rather mechanical geeky sort of tests. |
| 16417 | About a third of variation in human intelligence is environmental [New Sci.] |
| Full Idea: Possibly a third of the variation in our intelligence is down to the environment in which we grew up - nutrition and education, for example. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.10.29) | |
| A reaction: This presumably leaves the other two-thirds to derive from genetics. I am a big believer in environment. Swapping babies between extremes of cultural environment would hugely affect intelligence, say I. |
| 16418 | People can be highly intelligent, yet very stupid [New Sci.] |
| Full Idea: You really can be highly intelligent, and at the same time very stupid. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.10.29) | |
| A reaction: This is closely related to my observation (from a lifetime of study) that a talent for philosophy has a very limited correlation with standard notions of high intelligence. What matters is how conscious reasoning and intuition relate. Greek 'phronesis'. |
| 19484 | Psychologists measure personality along five dimensions [New Sci.] |
| Full Idea: Psychologists have long thought that measuring on a scale of just five personality dimensions - agreeableness, extroversion, neuroticism, conscientiousness and openness to new experiences - can capture all human variations in behaviour and attitude. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.06.13) | |
| A reaction: Researchers are considering a sixth - called 'honesty-humility' - which is roughly how devious people are. The five mentioned here seem to be a well entrenched orthodoxy among professional psychologists. Is personality more superficial than character? |
| 22607 | Time and space are not causal, but they determine natural phenomena [Ingthorsson] |
| Full Idea: Time and space are significant determinants of natural phenomena, and yet are not (typically) regarded as causal determinants | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1.4) | |
| A reaction: I like the word 'determinants'. Metaphysics largely concerns what determines what. I'm struggling to think of examples of this (which he does not give). Decay takes time, but isn't determined by time. Is a light cone a determinant? |
| 22605 | Humeans describe the surface of causation, while powers accounts aim at deeper explanations [Ingthorsson] |
| Full Idea: Humeans attempt to describe causation without any deeper ontological commitments, while powers based accounts attempt to explain why causation occurs in the way it is described. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1) | |
| A reaction: Exactly the view I have reached. The Humean view is correct but superficial. A perfect example of my allegiance to Explanatory Empiricism. |
| 22608 | Casuation is the transmission of conserved quantities between causal processes [Ingthorsson] |
| Full Idea: Causal process theories state that causation needs to be understood in terms of causal processes and their interactions, in which conserved quantities are transmitted between causal processes. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1.5) | |
| A reaction: Sounds a bit circular, but the idea of transmission of something is obviously the main point. I like this idea a lot (because it is so naturalistic), but rarely find it taken seriously. Energy is usually the quantity picked out. |
| 22621 | Causation as transfer only works for asymmetric interactions [Ingthorsson] |
| Full Idea: The transference model of causation only works for asymmetric interactions. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 4.11) | |
| A reaction: This is usually the transfer of energy. I liked the theory until I read this. |
| 22614 | Interventionist causal theory says it gets a reliable result whenever you manipulate it [Ingthorsson] |
| Full Idea: The core of agency and interventionist theories of causation is that c counts as the cause of e iff E reliably appears and disappears when you manipulate C. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 2.1) | |
| A reaction: [C is the type of c; E is the type of e] James Woodward champions this view. Ingthorsson objects that the theory offers no explanation of the appearances and disappearances. You can't manipulate black holes… |
| 22639 | Causal events are always reciprocal, and there is no distinction of action and reaction [Ingthorsson] |
| Full Idea: I accept the reciprocity of interactions, and abandon the Agent vs.Patient distinction, so we can no longer talk of the contribution of each as ontologically different types of cause. In interactions, neither action nor reaction can be separated. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 10.3) | |
| A reaction: His point is that we are misled by real world happenings, where one component is usually more powerful than the other (such as ball dropped onto a pillow). Modern science endorses his view. Mumford and Anjum seem to agree, and so do I. |
| 22615 | One effect cannot act on a second effect in causation, because the second doesn't yet exist [Ingthorsson] |
| Full Idea: Hobbes implies that a Kim-style event e1 existing at t1 cannot possibly act on an effect e2 at t2, because that effect does not exist until the Agent has worked its effect on the Patient to provoke a change, thus bringing the effect into existence. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 3.08) | |
| A reaction: [Hobbes Elements of Phil 1656 II.IX.1] Ingthorsson says that the Hobbes view is the traditional 'standard' view, that objects (and not events) are the causal relata. A strong objection to events as the causal relata. Realists need objects. |
| 22616 | Empiricists preferred events to objects as the relata, because they have observable motions [Ingthorsson] |
| Full Idea: It is the empiricists' refusal to deal with anything other than observable events that motivated the shift in conception of efficient causation …to influence by an event on another event (one motion on another) rather than by an object on an object. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 3.10) | |
| A reaction: I suppose events supply the necessary activity, whereas objects seem to be too passive for the job - because that's how they look. Ingthorsson persuades that objects are the correct causal relata, for those of us who believe in powers. |
| 22617 | Science now says all actions are reciprocal, not unidirectional [Ingthorsson] |
| Full Idea: It is now accepted as a fact of modern science that unidirectional actions do not exist, and that all interactions are instead thoroughly reciprocal. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 3.10) | |
| A reaction: Ingthorsson says this undermines the standard traditional view (Hobbes etc) of Agent and Patient, with A having active powers and P having passive powers. All influences are mutual, it seems. Passive powers are active structures? |
| 22619 | Causes are not agents; the whole interaction is the cause, and the changed compound is the effect [Ingthorsson] |
| Full Idea: By abandoning the standard view that causes are ‘extrinsic motive Agents’, an idea from pre-Newtonian physics, we are free to conceive of the interaction as a whole as the cause, and the change in the compound whole of interacting things as the effect. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 4.06) | |
| A reaction: Ingthorsson persuasively presents this as the correct account, as understood by modern science. It is not cause-then-effect. It is kerfuffle, then aftermath. |
| 22635 | People only accept the counterfactual when they know the underlying cause [Ingthorsson] |
| Full Idea: I doubt that anyone will accept any counterfactual as true unless they believe they know the underlying causality. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 9.3) | |
| A reaction: Correct. Almost any example will support it. Compare coincidences and true causes. |
| 22634 | Counterfactuals don't explain causation, but causation can explain counterfactuals [Ingthorsson] |
| Full Idea: I cannot identify any prima facie reason to think that causation can be explained in counterfactual terms, but plenty to think that causation can explain counterfactuals. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 9.1) | |
| A reaction: Love it. Treating causation as counterfactual dependency is hopelessly superficial. What is the reality that is involved? He cites the second law of motion. |
| 22637 | Counterfactual theories are false in possible worlds where causation is actual [Ingthorsson] |
| Full Idea: if there are worlds where there are causal powers and/or lawful connections, then they are worlds in which the counterfactual theory of causation is false, because there causes produce the effects, regardless of any possible world. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 9.6) | |
| A reaction: A nice modern instance of turning the tables. Come to think of it, possible worlds theories are just asking for that. Are there possible worlds in which there are no other possible worlds? Or the possible worlds are inaccessible? |
| 22624 | A cause can fail to produce its normal effect, by prevention, pre-emption, finks or antidotes [Ingthorsson] |
| Full Idea: Counterexamples involving prevention and/or interference have come to be roughly divided into four main categories: (i) prevention, (ii) pre-emption, (iii) finks and (iv) antidotes. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 5.3) | |
| A reaction: These are the reasons why necessity is denied in causation. i) is in the initial circumstances, ii) is another cause getting there first, iii) is a defusing action in the agent, iv) is a defusing action in the patient. No necessity if one is possible. |
| 22622 | Any process can go backwards or forwards in time without violating the basic laws of physics [Ingthorsson] |
| Full Idea: Because it makes no difference to exchange the time variable t with its contrary -t, in the fundamental laws of physics, any process can be described as going either backwards or forwards in time, without violating those laws. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 4.13) | |
| A reaction: A few philosophers read a lot into this, but I don't. The inverse scenario may not breach the laws of physics, but it does involve time going backwards, which I think we can skip for now. Entropy would be interesting. Can information flow backwards? |
| 22618 | In modern physics the first and second laws of motion (unlike the third) fail at extremes [Ingthorsson] |
| Full Idea: While the first and second laws of motion are known to fail in the domain of very fast-moving and massive objects (i.e. where relativity deviates from classical mechanics) as well as in the quantum realm, the third law is still assumed to hold good. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 4.04) | |
| A reaction: This implies a universal status for the third law (equal and opposite reactions), which the other two lack. Ingthorsson sees this as crucial for our understanding of causation. |
| 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. |
| 19950 | Entropy is the only time-asymmetric law, so time may be linked to entropy [New Sci.] |
| Full Idea: All our physical laws are time-symmetric, ...so things can run forwards or backwards. But entropy is an exception, saying that disorder increases over time. Many physicists therefore suspect that the flow of time is linked to entropy. | |
| From: New Scientist writers (New Scientist articles [2013], 2017.02.04) |
| 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) |
| 19478 | Light moves at a constant space-time speed, but its direction is in neither space nor time [New Sci.] |
| Full Idea: A light ray always moves at one unit of space per unit of time - a constant diagonal on the graph. ...But the direction that light rays travel in is neither space nor time, and is called 'null'. It is on the edge between space and time. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.06.15) | |
| A reaction: Don't understand this, but it sounds fun. |
| 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? |
| 19474 | Quantum states are measured by external time, of unknown origin [New Sci.] |
| Full Idea: When we measure the evolution of a quantum state, it is to the beat of an external timepiece of unknown provenance. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.06.15) | |
| A reaction: It is best not to leap to philosophical conclusions when studying modern physics. Evidently time has a very different status in quantum mechanics and in relativity theory. |
| 19473 | The Schrödinger equation describes the evolution of an object's wave function in Hilbert space [New Sci.] |
| Full Idea: A quantum object's state is described by a wave function living in Hilbert space, encompassing all of its possible states. We see how the wave function evolves in time, moving from one state to another, using the Schrödinger equation. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.06.15) | |
| A reaction: [These idea are basic explanations for non-scientific philosophers - please forgive anything that makes you wince] |
| 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) |
| 22630 | If particles have decay rates, they can't really be elementary, in the sense of indivisible [Ingthorsson] |
| Full Idea: We may wonder whether the fact that physics has calculated (and for some, confirmed) the decay rate of elementary particles can be a reason to think that they cannot really be ‘elementary’ in the philosophical sense of ‘indivisible’. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 7.6) | |
| A reaction: I don't think anything can ever conclusively be labelled as 'elementary', but this idea offers a reason for doubting whether a candidate particle is so basic. Does decay imply having parts? |
| 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) |
| 19954 | It is impossible for find a model of actuality among the innumerable models in string theory [New Sci.] |
| Full Idea: String theory has more than 10-to-the-500th solutions, each describing a different sort of universe, so it is nigh-on impossible to find the one solution that corresponds to our geometrically flat, expanding space-time full of particles. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.11.07) |
| 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) |
| 19953 | In string theory space-time has a grainy indivisible substructure [New Sci.] |
| Full Idea: String theory suggests that space-time has a grainy substructure - you can't keep chopping it indefinitely into smaller and smaller pieces. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.11.07) | |
| A reaction: Presumably the proposal is that strings are the true 'atoms'. |
| 19476 | String theory needs at least 10 space-time dimensions [New Sci.] |
| Full Idea: String theory needs at least 10 space-time dimensions to be mathematically consistent. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.06.15) | |
| A reaction: Apparently because of 'Ads/CFT', it may be possible to swap this situation for a more tractable 4-dimensional version. |
| 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) |
| 19947 | Hilbert Space is an abstraction representing all possible states of a quantum system [New Sci.] |
| Full Idea: The elements of the abstract mathematical entity called Hilbert Space represent all the possible states of a quantum system | |
| From: New Scientist writers (New Scientist articles [2013], 1017.02.04) |
| 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. |
| 19948 | Einstein's merging of time with space has left us confused about the nature of time [New Sci.] |
| Full Idea: Our hunt for the most basic ingredients of reality has left us muddled about the status of time. One culprit for this was Einstein, whose theory of general relativity merged time with space. | |
| From: New Scientist writers (New Scientist articles [2013], 2017.02.04) |
| 19955 | Space-time may be a geometrical manifestation of quantum entanglement [New Sci.] |
| Full Idea: A promising theory (based on the 'Maldacena duality' - that string equations for gravity are the same as quantum equations for surface area) is that space-time is really just geometrical manifestations of quantum entanglement. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.11.07) | |
| A reaction: This is a speculation which might unite the incompatible quantum and general relativity theories. |
| 19475 | Relativity makes time and space jointly basic; quantum theory splits them, and prioritises time [New Sci.] |
| Full Idea: Relativity says space and time are on the same footing - together they are the fabric of reality. Quantum mechanics, on the other hand, treats time and space differently, with time occasionally seeming more fundamental. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.06.15) | |
| A reaction: Interesting. When talking about time, people glibly cite relativistic space-time to tell you that time is just another dimension. Now I can reply 'Aaah, but what about time in quantum mechanics? Eh? Eh?'. Excellent. |
| 19949 | Quantum theory relies on a clock outside the system - but where is it located? [New Sci.] |
| Full Idea: After general relativity, quantum mechanics reinstated our familiar notion of time. The buzzing of the quantum world plays out according to the authoritative tick of a clock outside the described system, ...but where is this clock doing its ticking? | |
| From: New Scientist writers (New Scientist articles [2013], 2017.02.04) |
| 22610 | It is difficult to handle presentism in first-order logic [Ingthorsson] |
| Full Idea: Contemporary philosophers are not comfortable with presentism, because it is difficult to deal with presentism in the language of first-order predicate logic. | |
| From: R.D. Ingthorsson (A Powerful Particulars View of Causation [2021], 1.8) | |
| A reaction: Presumable that logic relies on objects which endure through time, or at least have a past. Second-order logic is better able to deal with processes, which only exist in the present, but nevertheless have an integral past and future. ? |
| 19951 | Entropy is puzzling, so we may need to build new laws which include time directionality [New Sci.] |
| Full Idea: Smolin observes that if entropy increases, the early universe must have been highly ordered, which we cannot explain. Maybe we need to build time directionality into the laws, instead of making time depend on entropy. | |
| From: New Scientist writers (New Scientist articles [2013], 2017.02.04) | |
| A reaction: [compressed] |
| 19477 | General relativity predicts black holes, as former massive stars, and as galaxy centres [New Sci.] |
| Full Idea: Black holes are predicted by general relativity, and are thought to exist where massive stars once lived, as well as at the heart of every galaxy. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.06.15) | |
| A reaction: Since black holes now seem to be a certainty, that is one hell of an impressive prediction. |
| 19952 | Black holes have entropy, but general relativity says they are unstructured, and lack entropy [New Sci.] |
| Full Idea: Black holes have a temperature, and hence entropy. ...But if a black hole are just an extreme scrunching of smooth space-time, it should have no substructure, and thus no entropy. This is probably the most obvious incompleteness of general relativity. | |
| From: New Scientist writers (New Scientist articles [2013], 2015.11.07) |
| 16420 | 84.5 percent of the universe is made of dark matter [New Sci.] |
| Full Idea: Dark matter makes up 84.5 percent of the universe's matter. | |
| From: New Scientist writers (New Scientist articles [2013], 2013.10.29) |
| 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. |
| 17604 | We are halfway to synthesising any molecule we want [New Sci.] |
| Full Idea: Ei-ichi Negishi (Nobel chemist of 2010) says 'the ultimate goal is to be able to synthesise any molecule we want. We are probably about halfway there'. | |
| From: New Scientist writers (New Scientist articles [2013], 2010.10.16) |
| 17603 | Chemistry just needs the periodic table, and protons, electrons and neutrinos [New Sci.] |
| Full Idea: Ei-ichi Negishi (Nobel chemist of 2010) says 'I work with the periodic table in front of me at all times, and approach all challenges in terms of three particles, positively charged protons, negatively charged electrons, and neutral neutrinos'. | |
| From: New Scientist writers (New Scientist articles [2013], 2010.10.16) |