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Remember that QM is as accurate (more in some aspects) as GR.
QM and GR are both incomplete on their own. But together they seem to describe the universe as accurately as we're able to measure. They must be compatible.
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My bad. I was talking about the distance between the event horizons the moment before they combine into a single event horizon. Though, now that I say it that way, I suspect we have the same problem with the extreme curvature of spacetime making the notion of distance meaningless.
Distance is "meaningless" anyway. We don't agree on distance unless we're moving with exactly the same velocity. Distance is entirely relative. You're in USA at a different latitude to me. You are therefore spinning at a different rate to me. Our velocities are different. So we observe different distances to the moon, for example. Of course, the discrepancy is completely unmeasurable to us without serious equipment, but there is a discrepancy. So what does distance mean even in the classical universe?
It just becomes more meaningless as velocity increases, or space decreases. But it was already meaningless.
btw, "meaningless" is probably the wrong word. Not sure what the right word is though. But distance has meaning in your own frame of reference.
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Why?Because h_bar seems to capture something about angular momentum in it. The units are the same, but it comes up with the reduced constant in many QM equations, like Schroedinger's Equation. And that seems relevant.
Yeah this is well beyond me. But so long as the Planck constant remains constant, then all is well. idk which of the lengths is "right". It's interesting this is related to angular momentum though. That's usually a 3D thing, but the 2pi ratio is very much a 2D thing. You're turning a line into a circle (radius to circumference), but not into a sphere. Curious.
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We consider the fundamental constants to be meter, second, kilogram...
I understand why these "fundamental" constants are arbitrary. I also understand that once one arbitrary value is chosen, that affects others. Like the millilitre and kilo, a gram is the weight of a millilitre of water. Change a millilitre, and you need to change the gram, too, which in turn changes the kilo.
But the Planck isn't like this. The Planck is derived though equations, it's not arbitrary (at least when we talk of the constant rather than length). So there's something more fundamental about the Planck constant than the meter.
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So the exact value of the Planck Length may not be meaningful
Ok, but the exact value of the Planck constant certainly is meaningful.
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BTW, the wind car on Veritassium stirred up a whole lot of controversy in the physics world
I saw this vid, it's interesting that it caused a stir in the physics community. I'll look into this.
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No, my gut says there wont be a graviton, but there is room in the Standard Model to account for such a particle.
The graviton doesn't make sense to me. If such a particle exists, then surely these particles are produced whenever anything accelerates. To argue that the graviton only exists because of gravity is to argue that Einstein's equivalence principle is wrong.