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I can tell you're deep into Physics as I am. To be honest I was presenting the "Standard Model" the way a professor would explain it to a student, who is trying

I can tell you're deep into Physics as I am. To be honest I was presenting the "Standard Model" the way a professor would explain it to a student, who is trying to explain QFT using the conventional beliefs held by most of the Physics community. I agree with everything you said, actually, except for this one sentence which you stated which I know is some kind of typo, because I doubt you think it's true: "Before a measurement takes place, the movement of electrons is predicted by a deterministic equation, there is no probability." That sentence goes against conventional wisdom so I doubt you meant it litterally. Anyway, if you want my own personal unproven belief (theory) here it is: (or a few aspects of it) I think our universe is a 3D (excluding time) manifold that is an event horizon in a larger higher dimensional space and what we call "Wave Collapse" is actually the point where an actual existing real particle does travel across our manifold. That is, anything that we can assign a position to in spacetime coordinates is also "on" this manifold. You can also call this manifold our "universe". So when something exists in what we call "Probability Wave" state that just means we haven't yet done something to pinpoint a particle "on" this (our) event horizon. Unless someone is a very good geometry mathematician they cannot really comprehend how our entire universe can be a "surface" in some a higher-dimensional space, and since it's unproven I generally don't bring it up on HN. I also believe all N-Dimensional spaces contain (N-1)-Dimensional constructs inside them. The example in our unsivers is 'black holes'. We see 2D (i.e (3-1)D) constructs where our physics fails and even have proven their informational content is proportional to surface area (Hawking+Susskind). Most people think black holes are 3D spheres, but they're really 2D surfaces to their "inhabitants". Similarly the higher dimensional universe in which our 3D space is embedded would see our universe similarly as some kind of construct where their own physics breaks down, and they are unable to "look" inside possibly, just like we can't see inside black holes. Also if we are an event horizon it disproves the big bang theory. The inhabitants of a black hole would notice their "universe" is expanding, and therefore conclude they came "from" some center point, but in reality BHs form from outside in, not inside out. So our universe came from outside itself not inside itself. It doesn't solve the 'first mover' problem, it just inverts it, but it does simplify it. All that to say, I appreciated your response and you're right I was putting the "professor hat" on when I described most of what I said on this thread, but the paragraph above should prove I'm capable of as much quackery as the next guy. lol.

tsimionescu 6y ago
Glad we mostly agree :) > I doubt you think it's true: "Before a measurement takes place, the movement of electrons is predicted by a deterministic equation, there is no probability." That sentence goes against conventional wisdom so I doubt you meant it litterally. I meant that very literally, and it is very important to understand. Quantum mechanics contains two fundamental postulates: 1. The Schrodinger equation: any quantum system can be described by the Schrodinger equation, which is a linear partial differential equation - i.e. it is completely deterministic. The solution of the Schrodinger equation is one or more wave functions - complex-valued functions which have some value for every point in space. 2. The Born rule: when a measurement is made of the state of a quantum system, the probability that a particular result will be observed is equal to the square of the amplitude of the wave function. To predict the state of the system after the measurement, the wave function must be updated to have the exact value of the measurement and no others. Without the Born rule, QM is completely deterministic, and predicts that particles have multiple positions. This prediction is actually correct until you measure anything. For an example, let's say you have a particle P0 whose wave function has some non-0 amplitude at far away locations A and B. Say you also have two other particles, Pa and Pb; Pa has amplitude almost 1 at point A and 0 elsewhere, while Pb has amplitude almost 1 at point B and 0 elsewhere. The positions of both Pa and Pb will be affected by the properties of P0. So, P0 was essentially in both places at once. However, if you add detectors for P0 at positions A and B, what you will notice two things: 1. If detector A detected P0, detector B will never see it, and vice-versa. The probability for each of them will correspond perfectly to the square of the amplitude that P0 had at that point. 2. If detector A detected P0, the position of Pb will no longer depend on any property of P0, and vice versa. So, the measurement changes the wave function of the P0, Pa and Pb system. The equation before the measurement is deterministic, and the equation after the measurement is also deterministic, but the switch from the first one to the second is probabilistic. By the way, an excellent resource on this topic is Sabine Hossenfelder's blog, for example this post: http://backreaction.blogspot.com/2019/10/what-is-quantum-measurement-problem.html http://backreaction.blogspot.com/2019/10/what-is-quantum-mea...
- WClayFerguson 6y ago
  We may be getting into semantics but QFT doesn't say electrons are even moving. It says there are no particles at all anywhere period full stop UNTIL the precise moment of measurement. This is the "Measurement Problem". The measurement CREATES the particle. The famous Bell experiment proved that the view of quantum mechanics as describing how particles "move" is incorrect, because the probability wave is not actually describing any movements of any actual particles. If you think of a single Hydrogen atom floating in space, no there is not an electron moving around it. There is no electron that exists at all "until" something interacts (according to Standard Model) with the wave function and causes the wave to collapse and "choose" a place in spacetime to materialize an "electron" in and only then is there an electron.

tsimionescu 6y ago

Glad we mostly agree :) > I doubt you think it's true: "Before a measurement takes place, the movement of electrons is predicted by a deterministic equation, there is no probability." That sentence goes against conventional wisdom so I doubt you meant it litterally. I meant that very literally, and it is very important to understand. Quantum mechanics contains two fundamental postulates: 1. The Schrodinger equation: any quantum system can be described by the Schrodinger equation, which is a linear partial differential equation - i.e. it is completely deterministic. The solution of the Schrodinger equation is one or more wave functions - complex-valued functions which have some value for every point in space. 2. The Born rule: when a measurement is made of the state of a quantum system, the probability that a particular result will be observed is equal to the square of the amplitude of the wave function. To predict the state of the system after the measurement, the wave function must be updated to have the exact value of the measurement and no others. Without the Born rule, QM is completely deterministic, and predicts that particles have multiple positions. This prediction is actually correct until you measure anything. For an example, let's say you have a particle P0 whose wave function has some non-0 amplitude at far away locations A and B. Say you also have two other particles, Pa and Pb; Pa has amplitude almost 1 at point A and 0 elsewhere, while Pb has amplitude almost 1 at point B and 0 elsewhere. The positions of both Pa and Pb will be affected by the properties of P0. So, P0 was essentially in both places at once. However, if you add detectors for P0 at positions A and B, what you will notice two things: 1. If detector A detected P0, detector B will never see it, and vice-versa. The probability for each of them will correspond perfectly to the square of the amplitude that P0 had at that point. 2. If detector A detected P0, the position of Pb will no longer depend on any property of P0, and vice versa. So, the measurement changes the wave function of the P0, Pa and Pb system. The equation before the measurement is deterministic, and the equation after the measurement is also deterministic, but the switch from the first one to the second is probabilistic. By the way, an excellent resource on this topic is Sabine Hossenfelder's blog, for example this post: http://backreaction.blogspot.com/2019/10/what-is-quantum-measurement-problem.html http://backreaction.blogspot.com/2019/10/what-is-quantum-mea...

WClayFerguson 6y ago
We may be getting into semantics but QFT doesn't say electrons are even moving. It says there are no particles at all anywhere period full stop UNTIL the precise moment of measurement. This is the "Measurement Problem". The measurement CREATES the particle. The famous Bell experiment proved that the view of quantum mechanics as describing how particles "move" is incorrect, because the probability wave is not actually describing any movements of any actual particles. If you think of a single Hydrogen atom floating in space, no there is not an electron moving around it. There is no electron that exists at all "until" something interacts (according to Standard Model) with the wave function and causes the wave to collapse and "choose" a place in spacetime to materialize an "electron" in and only then is there an electron.