The Einstein-Rosen bridge is a geometrical property of a black hole that manifests itself in that on the other side of the black hole another set of dimensions has been attached to the one from our universe. This makes passage through this bridge and hence into another universe a mathematical possibility. Actually the geometrical property exists in all black holes; it is called an Einstein-Rosen bridge only for static or Schwarzschild holes though. . There are three basic properties of a black hole: its mass, its spin, and its charge. Once these three are known, the black hole is completely specified. This is in immense contrast to the sun for example, for which one would have to specify huge amounts of data to completely describe her. A static black hole, that is one of no spin and no charge, is called a Schwarzschild hole. A black hole whose spin and/or whose charge is non-zero is a Reissner-Nordström hole, which is our object of curiosity. We shall not consider a hole of both charge and spin as this gives the situation an extra twist of difficulty. The mathematics of the hole of non-zero spin to that of non-zero charge is very similar (the a2, representing the angular momentum per mass, terms would replaced by Q2, representing the charge). However there are important differences. First of all the immense electric field around a charged hole is so great that the individual atoms arriving at it would be ripped apart long before they would reach the hole, whereas this is not the case for a rotating black hole. Both have a gravitational field of equal magnitude which is powerful, but not in all cases powerful enough to annihilate ordinary matter at a distance. Another difference is that with the charged hole, one can safely assume a point singularity, that is one can assume that all the matter of the hole is contained in a geometric point and that space-time has completely bent around this point, whereas with a rotating black hole one gets ring singularity, hence a spinning disk. Since the nature of the electric field around a charged hole leaves all contemplations of inter-universal travel no fertile ground, we shall only consider a rotating black hole. The following information was derived from Patrick Bangert at this location.
Interstellar Internet – how do we make it work? This is something that has been bothering me lately. How will we extend internet once we leave Earth and start colonizing other planets and/or solar systems. We know that conventional communication methods won’t work due to the distances involved even within our solar system. For example radio messages sent to Mars will arrive there anywhere in between 3 and 30 minutes depending on the relative positions of our two planets in orbit. Go farther than that and any reasonable attempts to communicate via radio will be futile.
Common solution to this used by a lot of science fiction writers is the use of wormholes. Simply create a stable Einstein-Rosen Bridge, leave one mouth on earth, fly the other one to Mars and then string a fiber optic cable through it. Boom! Instant interstellar internet connection with as much bandwidth as you can manage to fit through. That’s of course assuming we can figure out how to create stable wormholes and keep them open indefinitely.
The other idea for FTL communication is the Ansible introduced by Ursula K. Le Guin and since then used by various other writers (most notably Orson Scott Card in his Ender cycle). It is usually assumed that device works on the principle of Quantum Entanglement but even that vary depending on who your read. Le Guin herself for example explain it away by using “simultaneity” – a yet undiscovered force like (but different from) gravity which keeps the Ansibles in sync and allows for instantaneous interstellar communication.
One problem with the Ansibles in Le Guin’s books was that they had rather lower bandwidth. So instead of a microphone/camera they were usually equipped with a built in keyboard. You would type on one end, and the message would show up on the other. Problem was that someone had to monitor the Ansible 24-7 and respond to messages.
It’s a silly set up, I know. If an Ansible can send character data it can send any data. Instead of keyboard fit one with an Ethernet port and you are in business. Why no one thought to do that? Because the concept was introduced back in 1966 when the internet did not exist yet. Things like packet switched networks were just being developed at that time and since Ursula K. Le Guin was not a computer scientist, and didn’t follow the bleeding edge advancements in our field, she couldn’t know what was coming.
Now we know, however and knowing is half the battle. So an original Ansible from her novels could easily be turned from a glorified telegram machine into a full blown network node. In fact, here is how it could work:
This article is purely theoretical physics, that may or may not be practical in the future.
Further Reading and Information Courtesy: My Brain, Astrophysics 101, UCLA.
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