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The tricky part with black hole spaghettification is that the slope of the gravity gradient (tidal force) can be pictured as exceeding 90 degrees within the eve

The tricky part with black hole spaghettification is that the slope of the gravity gradient (tidal force) can be pictured as exceeding 90 degrees within the event horizon, because there is no speed limit for the flow of space. This doesn't violate physics because Einstein's speed of light limit only applies to matter moving within space. This idea has been embraced by astrophysicists to explain inflation at the start of the Big Bang. Why this matters is that when something spaghettifies, the particles at the end can never catch up to the ones at the beginning. The space between the ends of the spaghetti grows. Which also means that the spaghetti can never reach the pit at the center of the black hole, because the pit is farther ahead in its journey. So our intuition that falling into a black holes means that we'll collide with the center is incorrect. If we could survive the journey, we'd see ourselves falling forever towards something growing infinitely farther away. Like trying to catch up with a falling elevator that's moving faster than we are. From the outside, we see anything falling in as becoming 2D on the surface, red shifting as it accelerates away from us, becoming time dilated until it appears to freeze, never quite reaching the speed of light from our frame of reference. So even though it's being stretched along the radial axis and perspective should make it look smaller over time as our separation grows, it appears to stay the same size to us as it was when it entered the event horizon. So a black hole can be thought of as an infinitely long tunnel to.. somewhere. I prefer to think of it as a bubble which only grows internally. So in a very real sense, a whole universe is being birthed inside. Unfortunately the math breaks down near the singularity, so maybe the particles do see themselves colliding with a pit. For example, the sun is 8 light minutes from Earth, so even if it was heavy enough to collapse into a black hole, it should still take 8 minutes to reach the center for a particle falling towards it, from its frame of reference. But I don't think that's how it works. I think that the space flowing in faster than the speed of light overcomes spaghettification, creating a maximum strain inversely proportional to the mass of the black hole. Hawking hinted at this when he thought about what would happen to a human falling into a billion solar mass black hole whose tidal forces are weak enough that they're survivable. -- edit: this paragraph is wrong, the universe behind also red shifts, which I realized after considering that the object's watch and ours are synchronized during free-fall -- Probably what happens is that the object sees the universe behind it speed up faster and faster as it blue shifts, until it ends in a white-hot flash the number of light-seconds away that the object began falling. Meanwhile the space ahead appears to expand in the same way as inflation, creating a pocket universe containing the mass which has already fallen in. Except that the universe behind appears to also red shift, due to the increasing distance between the object and anything behind. The expansion and contraction probably balance to create a microwave background at a temperature inversely proportional to the age of the universe inside. So the background inside might be hotter than ours since the black hole is smaller than the parent universe. ---- Also if nothing more falls into the black hole and it starts evaporating, matter inside will see previously fallen matter growing away from it. Just like how we see stars and galaxies moving away from us faster than the speed of light when their distance times the Hubble constant exceeds the speed of light, causing our universe to grow lighter and expand faster, which we perceive as dark energy. So matter inside would eventually see the perimeter rushing towards it faster and faster as the black hole loses its mass, with its internal Hubble constant growing larger and larger until the expansion of space rips the matter apart as energy, back into the parent universe as its mass falls beneath a few solar masses. Which has implications for our universe, where instead of heat death, we re-experience spaghettification as the rate of the expansion of the universe keeps increasing until we explode. Or maybe the expansion only applies outside of our gravitationally-bound galaxy. So eventually the universe would only be our galaxy. But, I tend to think that evaporation still occurs, so even our galaxy would eventually be torn apart. But it would probably have already gone down the drain into the Milky Way's supermassive black hole, Sagittarius A*. In other words, the falling probably never ends. Which implies that maybe the universe is infinite, although we can never reach the parts moving away from us faster than the speed of light. Until we invent warp drive or meet aliens or something. Just so everyone knows, I completely made all of this up, starting from first principles after watching a lot of PBS Space Time and How the Universe Works. But that's ok since astrophysicists don't have a reference to point to that disputes my unfounded claims yet: https://jila.colorado.edu/~ajsh/insidebh/schw.html https://jila.colorado.edu/~ajsh/insidebh/schw.html Also, my description doesn't consider the quantum aspect of spaghettification, or how particles might behave inside gravitational barriers: https://en.wikipedia.org/wiki/Particle_in_a_box https://en.wikipedia.org/wiki/Particle_in_a_box https://en.wikipedia.org/wiki/Quantum_tunnelling https://en.wikipedia.org/wiki/Quantum_tunnelling I haven't found a clear summary yet for how the wave function behaves in a gravity gradient or under extreme time dilation, or when space is moving near or faster than the speed of light. Shoot, I just realized something after writing this out. Two particles in free-fall without external forces should have synchronized watches. The object falling into the black hole may not actually lose synchronization with us. Does anyone know if that's correct? https://en.wikipedia.org/wiki/Synchronous_frame https://en.wikipedia.org/wiki/Synchronous_frame https://www.physicsforums.com/threads/question-regarding-time-dilation-inertial-motion-and-acceleration-due-to-gravity.477834/ https://www.physicsforums.com/threads/question-regarding-tim... If the clocks stay synchronized until the lead object reaches the pit, what happens if the pit is never reached?

zackmorris 4y ago
Something like this: https://www.livescience.com/dark-energy-could-lead-to-a-second-and-third-and-fourth-big-bang-new-research-suggests https://www.livescience.com/dark-energy-could-lead-to-a-seco... If the ends of the spaghetti can never reach each other after space's rate of stretching passes the speed of light, then the spaghetti can never reach the pit. If the spaghetti never reaches the pit, then everything in the black hole falls forever. If everything falls forever, then the clock outside the block hole is synced to the clock of particles falling inside the black hole. Which suggests that a black hole forms an infinitely deep funnel, and if we entertain the idea that the rules of our universe keep working inside it, an hourglass. What does that look like? On Earth, space pours down our gravity well, reaching a stagnation point sometime before the center, which forms an indentation in spacetime which we ride in as we orbit the sun. In a black hole, there's still a stagnation point, if we consider the entire life of the black hole, including final evaporation. The bottom of the indentation falls at the speed of light, but eventually slows and rebounds as the black hole begins to shrink due to Hawking radiation, then springs back into our reality. In other words, the space inside a black hole is more dynamic than where we are. We're normally shown a picture of that falling floor tearing through our spacetime into an unknown place. But since the space is falling faster than the speed of light, I think that it crosses over itself and diverges, forming a white hole on the other side. The math of that white hole matches the math of the Big Bang. So we can picture the child universe as starting just like ours, and forming a sphere in the bottom of the hourglass expanding faster than the speed of light until its density gets low enough that the expansion proceeds at merely the speed of light. The same way that inflation worked in our universe. Particles at the edge of the sphere are able to leak back into the parent universe via Hawking radiation just like our galaxies at great distance slip out of our universe red-shifted faster than the speed of light. So the mass of the sphere begins to shrink, which slows its rate of expansion. Eventually its space starts to contract, [turning the child Hubble constant negative] <- edit: increasing its Hubble constant even higher. Everything begins to contract back towards one another. The edge of the sphere eventually rushes back inwards at the speed of light, creating a Big Crunch. It's not that matter is crushed together, but that space is contracting so fast out from under it that it has nowhere else to go but back up out of the throat. The final pop is reverse spaghettification, as each particle is torn apart back to quarks, electrons and energy back into the parent universe. The hard part to visualize is that the crunch happens inward towards each particle simultaneously, there is no center. The quantum mechanical aspect and notions like the Planck length are probably a distraction. An electron is always a point charge roughly the size of its uncertainty, in any spacial coordinate system. Maybe it has more mass and is a muon or tau (or something heavier), but it never stops being an electron fundamentally. When it spaghettifies in the throat, its wave function only has 2 degrees of freedom, along the radial axis and rotation, with the third degree along the time axis. Until space diverges again in the white hole on the other side and it's able to exist in 3D again. So our universe is the white hole on the other side of the black hole in the parent universe, and the universe is infinite, looking like swiss cheese with child universes and more black holes inside the bubbles. The centers of atoms may act like miniature black holes, but with slightly different rules involving the electroweak force and probability, creating an emergent force which we think of as the strong force. It's universes all the way down. This is the best mental model of reality that I've stumbled upon, but I'm sure it's wrong in important ways.

zackmorris 4y ago

Something like this: https://www.livescience.com/dark-energy-could-lead-to-a-second-and-third-and-fourth-big-bang-new-research-suggests https://www.livescience.com/dark-energy-could-lead-to-a-seco... If the ends of the spaghetti can never reach each other after space's rate of stretching passes the speed of light, then the spaghetti can never reach the pit. If the spaghetti never reaches the pit, then everything in the black hole falls forever. If everything falls forever, then the clock outside the block hole is synced to the clock of particles falling inside the black hole. Which suggests that a black hole forms an infinitely deep funnel, and if we entertain the idea that the rules of our universe keep working inside it, an hourglass. What does that look like? On Earth, space pours down our gravity well, reaching a stagnation point sometime before the center, which forms an indentation in spacetime which we ride in as we orbit the sun. In a black hole, there's still a stagnation point, if we consider the entire life of the black hole, including final evaporation. The bottom of the indentation falls at the speed of light, but eventually slows and rebounds as the black hole begins to shrink due to Hawking radiation, then springs back into our reality. In other words, the space inside a black hole is more dynamic than where we are. We're normally shown a picture of that falling floor tearing through our spacetime into an unknown place. But since the space is falling faster than the speed of light, I think that it crosses over itself and diverges, forming a white hole on the other side. The math of that white hole matches the math of the Big Bang. So we can picture the child universe as starting just like ours, and forming a sphere in the bottom of the hourglass expanding faster than the speed of light until its density gets low enough that the expansion proceeds at merely the speed of light. The same way that inflation worked in our universe. Particles at the edge of the sphere are able to leak back into the parent universe via Hawking radiation just like our galaxies at great distance slip out of our universe red-shifted faster than the speed of light. So the mass of the sphere begins to shrink, which slows its rate of expansion. Eventually its space starts to contract, [turning the child Hubble constant negative] <- edit: increasing its Hubble constant even higher. Everything begins to contract back towards one another. The edge of the sphere eventually rushes back inwards at the speed of light, creating a Big Crunch. It's not that matter is crushed together, but that space is contracting so fast out from under it that it has nowhere else to go but back up out of the throat. The final pop is reverse spaghettification, as each particle is torn apart back to quarks, electrons and energy back into the parent universe. The hard part to visualize is that the crunch happens inward towards each particle simultaneously, there is no center. The quantum mechanical aspect and notions like the Planck length are probably a distraction. An electron is always a point charge roughly the size of its uncertainty, in any spacial coordinate system. Maybe it has more mass and is a muon or tau (or something heavier), but it never stops being an electron fundamentally. When it spaghettifies in the throat, its wave function only has 2 degrees of freedom, along the radial axis and rotation, with the third degree along the time axis. Until space diverges again in the white hole on the other side and it's able to exist in 3D again. So our universe is the white hole on the other side of the black hole in the parent universe, and the universe is infinite, looking like swiss cheese with child universes and more black holes inside the bubbles. The centers of atoms may act like miniature black holes, but with slightly different rules involving the electroweak force and probability, creating an emergent force which we think of as the strong force. It's universes all the way down. This is the best mental model of reality that I've stumbled upon, but I'm sure it's wrong in important ways.