14 ideas
21110 | An understanding of the most basic physics should explain all of the subject's mysteries [Krauss] |
Full Idea: Once we understood the fundamental laws that govern forces of nature at its smallest scales, all of these current mysteries would be revealed as natural consequences of these laws. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 08) | |
A reaction: This expresses the reductionist view within physics itself. Krauss says the discovery that empty space itself contains energy has led to a revision of this view (because that is not part of the forces and particles studied in basic physics). |
21105 | In 1676 it was discovered that water is teeming with life [Krauss] |
Full Idea: Van Leeuwenhoek first stared at a drop of seemingly empty water with a microscope in 1676 and discovered in was teeming with life. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: I am convinced that this had a huge influence on Leibniz's concept of monads. He immediately became convinced that it was some sort of life all the way down. He would be have been disappointed by the subsequent chemical reduction of life. |
13768 | Validity can preserve certainty in mathematics, but conditionals about contingents are another matter [Edgington] |
Full Idea: If your interest in logic is confined to applications to mathematics or other a priori matters, it is fine for validity to preserve certainty, ..but if you use conditionals when arguing about contingent matters, then great caution will be required. | |
From: Dorothy Edgington (Conditionals [2001], 17.2.1) |
13770 | There are many different conditional mental states, and different conditional speech acts [Edgington] |
Full Idea: As well as conditional beliefs, there are conditional desires, hopes, fears etc. As well as conditional statements, there are conditional commands, questions, offers, promises, bets etc. | |
From: Dorothy Edgington (Conditionals [2001], 17.3.4) |
13764 | Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? [Edgington] |
Full Idea: Are conditionals truth-functional - do the truth values of A and B determine the truth value of 'If A, B'? Are they non-truth-functional, like 'because' or 'before'? Do the values of A and B, in some cases, leave open the value of 'If A,B'? | |
From: Dorothy Edgington (Conditionals [2001], 17.1) | |
A reaction: I would say they are not truth-functional, because the 'if' asserts some further dependency relation that goes beyond the truth or falsity of A and B. Logical ifs, causal ifs, psychological ifs... The material conditional ⊃ is truth-functional. |
13765 | 'If A,B' must entail ¬(A & ¬B); otherwise we could have A true, B false, and If A,B true, invalidating modus ponens [Edgington] |
Full Idea: If it were possible to have A true, B false, and If A,B true, it would be unsafe to infer B from A and If A,B: modus ponens would thus be invalid. Hence 'If A,B' must entail ¬(A & ¬B). | |
From: Dorothy Edgington (Conditionals [2001], 17.1) | |
A reaction: This is a firm defence of part of the truth-functional view of conditionals, and seems unassailable. The other parts of the truth table are open to question, though, if A is false, or they are both true. |
22001 | The real will of the cooperative will replace the 'will of the people' [Marx] |
Full Idea: Under collective property, the so called will of the people disappears in order to make way for the real will of the cooperative. | |
From: Karl Marx (Grundrisse [1876], p.563), quoted by Peter Singer - Marx 10 | |
A reaction: [from an 1874 note on Bakunin's 'Statism and Anarchy'] So how do you settle on the 'real' will of a cooperative? The travesty is when a ruling elite decide that, without consultation. An institution is needed. This is still a social contract. |
21109 | Space itself can expand (and separate its contents) at faster than light speeds [Krauss] |
Full Idea: Special Relativity says nothing can travel 'through space' faster than the speed of light. But space itself can do whatever the heck it wants, at least in general relativity. And it can carry distant objects apart from one another at superluminal speeds | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 06) | |
A reaction: Another of my misunderstandings corrected. I assumed that the event horizon (limit of observability) was defined by the stuff retreating at (max) light speed. But beyond that it retreats even faster! What about the photons in space? |
21104 | General Relativity: the density of energy and matter determines curvature and gravity [Krauss] |
Full Idea: The left-hand side of the general relativity equations descrbe the curvature of the universe, and the strength of gravitational forces acting on matter and radiation. The right-hand sides reflect the total density of all kinds of energy and matter. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: I had assumed that the equations just described the geometry. In fact the matter determines the nature of the universe in which it exists. Presumably only things with mass get a vote. |
21107 | Uncertainty says that energy can be very high over very short time periods [Krauss] |
Full Idea: The Heisenberg Uncertainty Principle says that the uncertainty in the measured energy of a system is inversely proportional to the length of time over which you observe it. (This allow near infinite energy over very short times). | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: Apparently this brief energy is 'borrowed', and must be quickly repaid. |
21106 | Most of the mass of a proton is the energy in virtual particles (rather than the quarks) [Krauss] |
Full Idea: The quarks provide very little of the total mass of a proton, and the fields created by the virtual particles contribute most of the energy that goes into the proton's rest energy and, hence, its mass. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 04) | |
A reaction: He gives an artist's impression of the interior of a proton, which looks like a ship's engine room. |
21112 | Empty space contains a continual flux of brief virtual particles [Krauss] |
Full Idea: Empty space is complicated. It is a boiling brew of virtual particles that pop in and out of existence in a time so short we cannot see them directly. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 10) | |
A reaction: Apparently the interior of a proton is also like this. This fact gives a foot in the door for explanations of how the Big Bang got started, from these virtual particles. And yet surely space itself only arrives with the Big Bang? |
21108 | The universe is precisely 13.72 billion years old [Krauss] |
Full Idea: We now know the age of the universe to four significant figures. It is 13.72 billion years old! | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 05) | |
A reaction: It amazes me how many people, especially in philosophy, would be reluctant to accept that this is a know fact. I'm not accepting its certainty, but an assertion like this from a leading figure is good enough for me, and it should be for you. |
21111 | It seems likely that cosmic inflation is eternal, and this would make a multiverse inevitable [Krauss] |
Full Idea: A multiverse is inevitable if inflation is eternal, and eternal inflation is by far the most likely possibility in most, if not all, inflationary scenarios. | |
From: Lawrence M. Krauss (A Universe from Nothing [2012], 08) |