In our Minkowski & newtonian model the apparent "spacetime geometry" is an illusion created by the newtonian gravity and increased inertia. To make a one-way membrane, one would need an infinite force, and such a force is not available. Thus, the event horizon cannot be one-way. Escaping from a black hole is very hard, but in principle, it is possible.
In our October 20, 2021 blog post we calculated that a 1 MeV photon passes through the horizon of a solar mass black hole in < 1.38 millisecond of the global Minkowski time. An "infinitely strong" event horizon would keep the test mass hovering above the horizon for an infinite time. Our result suggests that the real event horizon is not infinitely strong. If it is not infinitely strong, maybe it does allow photons to pass upward?
Conservation of energy dictates that the electron and the positron must annihilate; no need in gravity
An electromagnetic analogue of a black hole is a point charge, for example, an electron. We will discuss this ignoring quantum mechanics.
Let us imagine a device which lowers a positron toward an electron. The device can harvest ever more energy from the process and send the energy away. If the particles would not annihilate, then we could harvest infinite energy from the process.
Either there is no conservation of energy, or we end up with an object which possesses negative energy. Both alternatives are bad. Nature has saved us from this paradox by making the electron and the positron to annihilate.
gravity gravity
mass ---> <--- mass
● |-------------------____________| ●
energy harvesting
device
In gravity, the problem of infinite energy does not exist.
Let us assume that the original mass-energy of the system in the diagram, as seen by an outside observer, is E.
Suppose that the device harvests some amount of energy. The device sends the energy away to an outside observer. Let an outside observer receive W of energy. Now the gravity charge E of the system has become W less. If the outside observer receives the entire E of energy, then the gravity charge of the system is zero, and there no longer is any pull of gravity. Thus, the outside observer cannot receive more than E.
For a local observer in the system, it may appear that energies grow toward infinity, but that is not relevant for the physics of the system. The physics obey the gravity charges as measured by an outside observer.
The difference to the analogue of the electron and the positron is that the gravity system loses charge as it outputs energy.
Canceling gravity with an electric charge
In a blog post on January 12, 2022 we argued that one can cancel all effects of gravity with electric repulsion. If we have an electrically charged black hole, then a suitable electrically charged object can move down through the event horizon as if it were moving in empty space. It can as easily come up through the event horizon. The horizon is not a one-way membrane for such an object.
Having a one-way membrane breaks classical thermodynamics; Hawking radiation
Jacob Bekenstein and Stephen Hawking argued that a black hole contains a lot of entropy, and in classical thermodynamics, an object with lots of entropy should radiate energy, when it is seeking a lower entropy state.
A perfect crystal does not radiate because it is in the lowest entropy state. A block of glass radiates because atoms there slowly order themselves into crystals, releasing heat.
The black hole of general relativity is problematic because it contains a lot of entropy, but cannot radiate at all. It seems to break classical thermodynamics.
Stephen Hawking invented hypothetical Hawking radiation to remedy the problem. A black hole does radiate, after all. But the famous information paradox arose: how is the information in the entropy carried away in Hawking radiation?
In our Minkowski & newtonian model, photons probably can go up through the event horizon. They lose almost all of their energy in the redshift. That is why the black hole appears almost black.
The black hole information paradox
The temperature of a black hole appears almost zero for a faraway observer, whereas a local observer will feel extremely high temperatures.
To obey classical thermodynamics, there must be very many degrees of freedom in a black hole, so that the thermal energy in it has a very low temperature, as seen by a faraway observer.
It may be that our Minkowski & newtonian model solves the information paradox.
A black hole radiates away its entropy as thermal radiation. Since there are many degrees of freedom, the temperature of a solar mass black hole is extremely low, and the radiation is very weak. The information in the entropy is carried away in the thermal radiation. There is no information paradox.
A similar effect happens with a neutron star, too. A faraway observer sees it having a lower temperature than a local observer.
Could it be that particles inside a black hole collide and produce gravitons? Gravitons collide, too, and produce smaller gravitons. The kinetic energy and heat escape quickly into a huge space of gravitons. There are so many degrees of freedom in the space that the temperature becomes extremely low.
A similar process cannot happen in electromagnetism because the photon has no electric charge.
Maybe the thermal radiation from a black hole is very low-energy gravitons?
The final fate of a black hole
A black hole keeps radiating as long as its entropy is above the minimum possible level. It is like a block of glass which is cooling down in space.
Conservation laws suggest that the black hole will keep baryons and other matter inside. If matter remains inside the black hole, the final state is some kind of a "crystal" where matter has reached its minimum energy state. The final fate of a black hole is just like the final fate of a block of glass.
If all matter somehow decays into massless particles, then the final fate probably is a "black hole explosion", about which Stephen Hawking speculated in his 1974 note in the journal Nature.
Conclusions
General relativity has yet another problem: the one-way membrane in a black hole breaks rules of classical thermodynamics.
Stephen Hawking tried to remove the problem with Hawking radiation, but could not solve the information paradox.
We will investigate if our model solves both problems. Since our model is classical physics, thermodynamics should work in the right way.
The analogous problem with neutron stars is a good starting point.
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