I watched a great video on FTL Communication (mainly dealing with the problems with this Technology https://www.youtube.com/watch?v=BLqk7uaENAY&t=1445s)

I am worldbuilding an empire that needs FTL Communications. I understand the number one issue with this form of FTL is that you don't know what you are going to observe when you make an observation.

BUT in my world (which is sort of a Space Western with Wizards) there is a use of magic to affect probability directly forcing the spin to be up or down and allowing them to force the data across space faster than light.

My question is, if this was the case, how would be the best way to transmit information like this. Are there other technologies that I could do some research into to give me a basis of information to inspire me. Thanks!

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    $\begingroup$ Do you need FTL for your story? I presume yes. Then just have the tech. Hang a lamp shade and carry on. Thorough if it is going to be a significant plot point better have consistent rules as to how it operates. Be it million fold speed up or is it message in the bottle of an FTL ship. or have to have already delivered x entangled bits to have a conversation x bits long. $\endgroup$ Nov 22, 2022 at 1:47
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    $\begingroup$ "The number one issue with this form of FTL": What form of FTL? There is no form of FTL described in the question. $\endgroup$
    – AlexP
    Nov 22, 2022 at 2:02
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    $\begingroup$ "mainly dealing with the problems with this Technology" 🤔 I'm curious, did they mention the biggest problem with this tech, that it's fantasy (likely originating in some physicist taking the pee out of some poor ignorant reporter interviewing him, but that's just me guessing of course 🤗) that's completely impossible in the real world and not a real thing at all? 🤨 .. that doesn't mean you can't use it in a story of course, just be aware it's science fiction rather than science fact that's ever going to exist in the real world. $\endgroup$
    – Pelinore
    Nov 22, 2022 at 3:44
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    $\begingroup$ Entanglement does NOT give you FTL communication. That was a tedious homework assignment my first year in grad school (mumble) years ago. If magic lets it do so then it's up to you how the magic works. $\endgroup$
    – Boba Fit
    Nov 22, 2022 at 12:55
  • $\begingroup$ @BobaFit in my case a frustrating four days off and on as a non-physics student wading through copious bull articles trying to figure out through web-searches the basis for the whole idea and then understand what the double slit experiment actually is and what's happening in it .. very annoyed at the end when I worked out how bull the whole thing is 🤗 took so long because I had (media friendly) 'experts' in some of those articles seemingly telling me it was 'sort of' real, added a lot of chaff to the picture which obscured the real stuff, which was the main cause of the annoyance. $\endgroup$
    – Pelinore
    Nov 22, 2022 at 16:25

2 Answers 2



Put two particles in two boxes. Magically entangle them so Box A contains the receiver particle and Box B contains the transmitter particle, meaning the state of particle B will instantly change whenever we change the state of Particle A

Then put one box in Toronta and the other in Epsilon Centauri Prime, and have someone oscillate the transmitter particle between up and down spin. Have someone else record the spins of the receiver particle. It might look something like this:

up-down-up-up-down-down-down-down-down-up-down-. . .

Convert that to binary code

10110000010. . . .

Congratulations. You can now send binary messages faster than light. This is how real wireless messages are sent. So you can send anything, once you agree a way to decode the binary.

  • $\begingroup$ Now my question that I couldn't find answers to. How often can you switch? $\endgroup$
    – VedHanna
    Nov 22, 2022 at 23:46
  • $\begingroup$ @VedHanna As often as you want. If there is a practical limit then just add extra pairs of particles. $\endgroup$
    – Daron
    Nov 23, 2022 at 10:28

Ok, let's talk about magic. As always, you get to pick your magic. If there's magic, then you can open FTL magic mirrors between two spots in the universe. You could use said magic mirrors in conjunction with a double-slit experiment if you want, but the communication is already done. So where does the magic come in?

If you're insistent upon having pseudoscience magic involving quantum entanglement, then I would suggest that you allow them to use the principles of Sympathy and Contageon to magically entangle the particles, such that you can retroactively determine what the up/down states are when you send the message. You'd still need a pipeline of pre-entangled particles between the two locations.

Another possibility is that you could use prophecy at the generation point, possibly making the point that not revealing the message until it's actually sent prevents the prophecy waveform from prematurely collapsing.

Most cases of mixing of magic and quantum theory just involve using quantum technobabble to describe the magical behaviors. Have fun with it.


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