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Ideas for 'Parmenides', 'Identity and Existence in Logic' and 'New Scientist articles'

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6 ideas

27. Natural Reality / B. Modern Physics / 2. Electrodynamics / a. Electrodynamics
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.
27. Natural Reality / B. Modern Physics / 2. Electrodynamics / d. Quantum mechanics
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.
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]
27. Natural Reality / B. Modern Physics / 5. Unified Models / b. String theory
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'.
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.
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)