With our current understanding of physics it is not possible to send anything into the past (although GR mathematically allows it).

Could an intelligent alien species with a 100,000+ year head start on us possibly do such a thing with a wormhole or similar to create a CTC? With the CTC always online it would allow them to send a message backward in time and correct or change things on the fly (one time line) which would wreak havoc possibly on their existence so I imagine it’d be heavily guarded.


closed as primarily opinion-based by bilbo_pingouin, Elmy, StephenG, Mołot, Confounded by beige fish. Feb 12 at 11:51

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ Welcome to worldbuilding, please take the tour and visit the help center to understand what we expect from our users. Your question can be hardly answered: first of all, now everyone knows what a CTC is, then, how can we know what a civilization can come up in 100k years? People in the 60es were not able to predict the smartphones, and it was 50 years ago. Any answer to your question would be based on opinions, so not a good fit for this community, If possible try to rework your question. $\endgroup$ – L.Dutch Feb 12 at 10:03
  • $\begingroup$ What a science 100,000 years in advance of ours may or may not be able to do is quite simply opinion based (wild guesses). $\endgroup$ – StephenG Feb 12 at 10:53
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    $\begingroup$ Meaningful answers to this question will be possible 100,000+ years from now. $\endgroup$ – Mołot Feb 12 at 11:22
  • $\begingroup$ Like @B.fox I believe the answer is in your question. Given its premises, yes they would. Any sensible civilization with time travel will take steps to protect its past. This is irrespective of whatever their culture or technology will be. $\endgroup$ – a4android Feb 13 at 12:30

You essentially answer your own question in your own question. With our current understanding of the physics involved, GR, time travel seems on the table given some interpretations.

If travsersable wormholes may exist, and they are horizon-less and singularity-less, then travel between points of space-time is possible. Closed timelike curves would also be useful in this regard.

What happens when you traverse these things is entirely up to your subjective interpretation, i.e., whether or not there is a horizon or singularity, or something else entirely, to deal with upon crossing.


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