# Protocol between an information sharing black and white hole pair

Premise: Imagine a "sender" construct that has the ability to create it's own micro black hole and send information as light into it. On the receiving end, a "receiver" construct would contain it's own white hole paired to that black hole to receive the information (essentially transferring at a apparent faster-than-light rate).

Situation: For simplicity, imagine one sender and two receivers in the shape of a 3 light year equilateral triangle. I want to send information to one of the two receivers.

Problem: If I want the sender to open a black hole and the specific receiver to open a white hole, the sender needs to contact the receiver and go through some type of "handshake" that tells the receiver to open that white hole because information is coming. However, for that handshake to work, information needs to be transferred and because there's no black hole connection established yet the information would need to be send via 3rd dimension like starlight and thus would take three years to even reach the receiver, which defeats the purpose of apparent faster-than-light data transfer in the first place.

Question: How can this connection problem be solved assuming (our best) current understanding of physics?

Restriction: Looking for an answer that does not include the sender maintaining a black hole open to every single receiver indefinitely.

• Can you make a phone call to someone with their cell turned off? No. Same here. On top of that how are the white and black holes connected? It's not like you have a medium to broadcast into to let the other end know to connect (without using real space and time constraints) Nov 2, 2015 at 16:04
• Bowlturner's comment makes perfect sense. While the cellphone isn't on a call, it's still connected to the network (ie sending/receiving status messages). To push the analogy a little, it's like your phone connecting to the cellphone towers via carrier pigeon, until a pigeon turns up to say you have a call incoming from a caller on frequency x, at which point you turn on your phone and tune in to your caller's frequency. Admittedly that's an oversimplification of the cellphone network, but.. Nov 2, 2015 at 16:21
• @JoeBloggs your analogy makes perfect sense, that's how I was perceiving my situation. Bowlturner's statement is assuming the phone is off off, at which point it's not still connected to the network at all until it's turned on and then it would be in the state in which you described, and possible to make or receive a call. Nov 2, 2015 at 16:25
• I think I changed contexts partway through my comment there. Bowlturners comment makes perfect sense, however Bowlturner's comment isn't exactly applicable to your question. analogy here. :) Nov 2, 2015 at 16:28
• How much energy does it take to open the blackhole/whitehole? I don't have any references, but I remember the cost of changing the topology of the universe was equal to the change in energy caused by the sudden new "shortest path" between points at different potential energies. If so, opening and closing holes is expensive! Nov 2, 2015 at 16:28

Simple answer? It can't. You can't violate the speed of light in a classical paradigm without also getting funky with either Time (which I'm pretty sure works) or special relativity (which I'm also pretty sure works)

However: Since you're positing that you can send signals at FTL speeds using paired black/white holes (which is breaking physics to start with) you can pretty much do what you like with the handshake protocol using your already existing holar pairs. Extend the same technology to be able to send temporary perturbations at FTL speeds but to be unable to send intelligible information without a built receiver, then have the receiver listening for perturbation when not actively connected. That resolves the issue, but doesn't meet all of the constraints of your question (namely that superluminal signalling can't be used unless subluminal signalling is used)

If you don't like that: It's probably best to have a hub and spoke arrangement. All black holes are permanently paired to one white hole, and one half of two pairs of these are sent off into space, with all the others remaining on Earth. Earth then acts as an exchange, passing information from one sender to another receiver, and thus enabling communication from any point to any point without having to have all points permanently connected to all points. It also gives Earth a lot of political power.

Cue intrigue...

• Further addition to "can't": small black and white holes are no joke: youtube.com/watch?v=8nHBGFKLHZQ
– Dane
Nov 2, 2015 at 15:47
• No laws of physics broken- I used the term "perceived FTL" (edited to "apparent FTL"), the idea being something disappearing in a black hole and emerging at a white hole travels a shorter path from point A to point B than if it traversed there around space. From an outside observer seems to have traveled faster than light but really just took a shorter path. See: bit.ly/1P62S9Y Nov 2, 2015 at 15:54
• I meant 'breaking physics' in more of a 'white holes, being completely hypothetical to start with, have no known way to make/break such a connection.' That's the bit that you're building into this world, and as such you're making the rules about how that connection forms. Also worth noting: If such a wormhole can be established and then broken and re-established, then your wormholes can be used to violate causality and cause an actual FTL event. In fact I'm pretty sure that relativity says that's the case anyway. Either way, not really important for the narrative of your world. Nov 2, 2015 at 16:11
• Ah, fair enough. That companion information along with your answer makes a lot more sense. I'll have to reconsider my premises and try to ask again another time. Nov 2, 2015 at 16:22
• Hey, it's a perfectly good question if you are willing to accept that one small break in physics. There are a lot of major SF novels and series that blatantly ignore (and make no allusions to) the laws of physics. If everything asked on here made perfect sense then this would be called physics.stackexchange. Nov 2, 2015 at 16:24

This reminds me of a recent news article about scientists proving that quantum entanglement is real even at larger distances.

If it is possible to send one of a pair of entangled particles through this type of tunnel, capture it and keep it at the receiving end, you could then signal to the receiving party that they should open the white hole to receive data, by changing the "spin" of the particle in a certain sequence.

Otherwise, the entangled particles would either have to be taken along by who or whatever was originally sent to set up the receiving stations, or sent after them in the same way once the technology to create and use the entangled pairs was invented. This might take many years if not included in the original mission.

Small amounts of data could be transferred in binary form using just the entangled pair, and that might have been the primary communication method until the receiving stations are ready, but I suppose you'd want the black hole/white hole tunnel for bigger stuff.

• This is a wonderful misconception about quantum teleportation. Information can't be transmitted using entangled particles unless the person at the receiving end already knows what the message is going to be, at which point you've just sent a regular message. Nov 2, 2015 at 16:14
• The article I linked to seems to suggest that the researchers do claim to have made steps towards sharing measurements. But you are right, I did misunderstand the concept (just looked it up) Nov 2, 2015 at 16:33
• Yeah, it's a weird one. We can transmit information, and we can show that it was done instantly, but sadly we can only show it if we've already transmitted the information slowly. Gotta love quantum mechanics. Even more fun is quantum cryptography. It's nowhere near as cool as it sounds, but it's pretty mindbending nonetheless. Nov 2, 2015 at 16:36