4 ms·
My version of this is as follows. Every theory starts with a collection of objects that it postulates exist in the world or system being studied. According to
by abdullahkhalids 4y ago
My version of this is as follows. Every theory starts with a collection of objects that it postulates exist in the world or system being studied. According to a child's theory of the world, ghosts exist and could be lurking in the dark. In an adult's theory of the world, ghosts don't exist.
In basic classical physics the world is made up of the following objects:
1. Point particles i.e. every mass must be modeled as a particle located at exactly one point in space at every instant of time, and having no dimensions.
2. Waves, like sound waves and water waves. These were masses that moved with some symmetry and carried energy from one place to another.
More advanced classical physics is able to postulate that the world also includes masses that are not point particles, but spread out over space. Moreover, it postulated that these particles and waves moved due to the influence of
3. Electromagntic and gravitational fields.
This is why, when quantum phenomena was encountered, people tried to put mass objects into these buckets 1 and 2 of particles and waves
Except when quantum theory was developed in 1920s/1930s, it postulated that the world was made up of only one type of "mass" object.
* Quantum fields, which are somewhat similar to water waves, but actually fundamentally very different types of mathematical objects.
The change in these fields continues to be driven by electromagnetism. That's all there is to it. There is no notion of "particles" within quantum theory.
But somehow my fellow physicists have continued to be confused for a century and keep harking on about this concept of wave/particle duality, which has little explanatory value and even less predictive value.
- ravi-delia 4y agoObviously you're correct, but you have to admit that the universe pulled a funny one here. "Particles" aren't the emergent property of quantum fields the way you'd hope. Unlike other classical phenomena, where you can sum up all the wave behavior and see where the classical illusion comes from, fields just kinda describe amplitudes over possible particle positions. We shift from configuration to configuration precisely as governed by the fields, but its over a configuration space of particles! What the hell!? Who wouldn't be confused? I honestly won't be happy until QFT has a good explanation as to why it feels the need to pretend perfect inviolable particles exist (the universe, of course, is under no obligation to oblige, but I am under no obligation to die happy).
- namaria 4y agoY'all squinting too hard looking into formulas. The artifacts we use to calculate results of experiments are not the fabric of the cosmos.
- abdullahkhalids 4y agoI am sure GP is aware of the difference between reality and the map of reality. But creating maps are shown to not correspond to reality and others that do a pretty good job for parts of reality do say something about what the fabric of the cosmos could and could not be. The most striking example of this is Bell's experiments which wipe out entire classes of fabrics.
- namaria 4y agoSure, understanding the logic behind validating reality models is very useful. Surely, you also can see that pretending like valid reality models are more then useful, but a representation of the very nature of existence, is just a flight of fancy. We don't know what is reality, why is reality, and the bulk of it lies eternally beyond us, towards past and future. Sure we can figure out reality, it's all about tunnels baby! Says the ant.
- zmgsabst 4y agoSure — but equally so is the response to Bell’s inequality that we must live in a non-deterministic world… even though that’s a purely extraneous assumption (ie, we’re non-local either way). Yet, for longer than I’ve been alive physicists have blathered about this “quantum truth” that’s purely an artifact of extraneous assumptions, so far as anyone can show me.
- akimball 4y agoIs it extraneous to interpret schrödinger psi as a probability amplitude? If not, then all fundamental interactions are stochastic.
- 4y ago