5 ms·
Being able to send messages faster than the speed of light grants the ability to send messages to yourself in the past. [0] If you can send messages to yourself
by nwallin 5y ago
Being able to send messages faster than the speed of light grants the ability to send messages to yourself in the past. [0] If you can send messages to yourself in the past all manner of causality goes out the window.
First of all, it gives you the ability to solve NP-complete problems trivially.
Step 1: you receive a message from yourself from the future. It explains the problem, gives you a potential solution. Let's say you ask yourself to solve boolean satisfiability, gives you the problem statement, and then a potential solution. You check the solution: If the possible solution is correct, you send yourself an identical message. If the solution is not correct, you send the next possible permutation of the answer. So if you sent yourself the possible solution TTFTFTTTFTFFTTTFTF, you send yourself TTFTFTTTFTFFTTTFTT. If there are no further possible permutations, then you send yourself a statement saying that the problem is not solvable. You've created a time paradox; a future in which you send yourself an incorrectly solution is logically inconsistent. The only consistent universes are the ones where you send yourself the correct solution or not-solvable, and all other universes (starting with the one where you sent yourself the message FFFFFFFFFFFFFFFFFF) collapse into the valid one.
https://en.wikipedia.org/wiki/Tachyonic_antitelephone https://en.wikipedia.org/wiki/Tachyonic_antitelephone
- drran 5y ago> Being able to send messages faster than the speed of light grants the ability to send messages to yourself in the past. No, it doesn't. Even if we will be able to communicate instantly (0 delay = infinite faster than speed of light), we will not be able to send a message to the past (negative delay).
- nl 5y agoIt does. Read the numerical example on https://en.m.wikipedia.org/wiki/Tachyonic_antitelephone https://en.m.wikipedia.org/wiki/Tachyonic_antitelephone
- drran 5y ago1) It's not applicable for this kind of drive. Isn't? 2) It's an unsolved problem, which waits for a correct solution. 3) Next time, please read what you are posting, please.
- nwallin 5y ago1) It's applicable for any kind of ... thing ... which lets you send a message faster than the speed of light. It doesn't matter if you build this kind of drive into a USPS truck, or if it's a special closet in an unused bedroom, or a carrier pigeon that flies really fast, or a garden gnome that you hand an envelope to and he's just not there when you go to look for him until he then pops up and says "speedy delivery!" and hands you an envelope from yourself from the future. 2) It's an unsolved problem because it's built on a foundation which is also an unsolved problem -- namely faster than light travel/communication. If -- if -- we solve the problem that it's built on, all indications are that sending a message to your past will become possible. That being said, I expect that it's impossible because I expect that FTL travel/communication is impossible.
- nl 5y agoThese responses are correct. I'll add: 3) yes I read it. It's an example Einstein created, so possibly worth responding to the points made there rather than attacking me for "not reading it".
- drran 5y agoIf you read it and understood it, can you show us how to apply this formula to the warp drive, please? I cannot ask Einstein, obviously.
- nl 5y agoIt exactly applies to a warp drive. Just saying "warp drive" doesn't have magical qualities - it's exactly what Einstein was talking about. So you put in the numbers in the same way as that numerical example on Wikipedia, and it shows the same thing. Edit: the only exception I can think of is if causality can be reversed.