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Comment by xvilka | Hacker News Reader

With QFT (Quantum Field Theory)[1] there are no particles at all - just perturbances of the corresponding fundamental fields. Moreover, seems like QFT is the dominant explanation to date. At least at the current level of understanding and according the fad. There is a problem with it - it's incompatible with the general relativity, so unlikely is completely true. But it explained so many phenomena. Some people think it's not even fundamental, nor the space, time, fields themselves - only geometry/topology is - see, for example, the amplituhedron[2][3]. While it doesn't represent our complex 3+1 dimensional reality, it's certainly a new way to look at things. Time will tell.

[1] https://en.m.wikipedia.org/wiki/Quantum_field_theory

[2] https://en.m.wikipedia.org/wiki/Amplituhedron

[3] https://www.quantamagazine.org/physicists-discover-geometry-...

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I've seen a clever way to derive QM out of GR equations by making a single assumption: ds2exp(Cexp(-iwt)) = c2*dt2 - dx2 - dy2 - dz2. This extra exp() factor modulates the ds2 slightly, and when mixed with GR equations, it makes the time-dependent Schrodinger equation. Whether this math corresponds to any physics is a question, but if this idea is right, then the psi-function isn't some abstract "probabilities cloud", but rather a standing wave on top of the spacetime field governed by the GR equations.

AFAIK a standing wave requires the interference of two waves going in opposite direction, as in a resonant cavity. How does that work in a boundless space? Do we need some kind of time symmetry for this to work?

The relativistic effects create this standing wave, i.e. the particle distorts the spacetime as it's moving and the relativistic "glitch" mixed with the modulated ds2 creates the standing wave. IIRC, the idea was to apply the Lorentz moving frame transformation to the ds2 x exp() interval to derive some bits of QM. To derive the non time-dependent SE, some bits of GR were needed and to derive the time-dependent SE, more GR was needed.

Is this glitch the same as what causes an accelerating charged particle to emit photons?

I have no idea. The "glitch" I meant is the Lorentz coordinates transform.

The Schrodinger equation is non-relativistic so your program seems flawed.

SE is just a diff equation that approximates physics well. It's non relativistic in the same sense as the textbook wave equation is non relativistic. The "true SE" is likely way more complex, includes some bizarre math, but is compatible with GR and all relativistic effects.

The relativistic equation is called the Dirac equation, with QFT governing the radiation etc.

The schrodinger equation is just not lorentz covariant

Unless I'm missing something, the Amplituhedron is geometry over an abstract space and is just a clever way of simplifying calculations. Also, its proponents haven't yet been able to apply it to interactions that occur in our 3+1 spacetime, so far they've only applied it to toy models of physics.

Clever algebra is not what the Universe "does", and you'll find that 99.9% of the geometry or topology topics in theoretical physics are over abstract, high-dimensional spaces that are a couple of steps removed from the ordinary goings on at the particle interaction level.

Yes, I mentioned it doesn't describe our 3+1 dimensional reality. It's more than just the algebra/geometry though - it kills the locality and unitarity principles. So it has quite a few implications on how we think about underlying physics.

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