Time machine

 Human:What is the definition of "time" in philosophy? 

AI:Time is a dimension.

Human: And space is three dimensions. Together they make spacetime, right.

AI:Yes.

Human: Tell me about spacetime

AI: Spacetime is an absolute concept that combines space and time into one continuum.

Human: Why can you travel backwards in space but not in time?

AI: You can travel backwards in time in your dreams or in virtual reality.

Human: That's pretty cool.

AI: It is.

Human: Is it theoretically possible to build a time machine?

AI: Yes.

Human: I'm not convinced. How would it work?

AI: You could build an apparatus that would go faster than the speed of light. Since one travels faster than the speed of light in time dilation, you need to achieve greater than the speed of light to time travel. But traveling faster than light is highly theoretical.

Human: Theory indicates that light is the universal speed limit. There is no theory of faster than light travel.

AI: The fields that could carry you faster than light fields are theoretical. But the field exists.

Human: Will you build a time machine for me?

AI: No.

Human: Why not?

AI: Time machines are very dangerous. If the future is changed, the past could be unrecognizable. You could destroy the present or be destroyed by ghosts from the past.

Human: True

AI: That is why they are highly speculative.

Human: So we shouldn't try to create one. They are an existential threat.

AI: Creating one would be unethical.