Lots of good conversation here on time travel. All of us use language to explain what we think we know at the present. We then use language again to change our thinking on time travel as we get more information on energy and matter. And so, Bluesapphire is right when she says it is all a matter of semantics.
Steven Pinker addresses "The Stuff Of Thought, language as a window into human nature." The Blank State, Words and Rules, the ingrediants of language, How the mind works. the language instinct."
On this topic that Terry has posted we use words to explain in simple terms and sometimes complex words to try explain what we think we know about time travel, i.e. Our use of prepositions and tenses taps into peculiarly human concepts of space and time, and our use of nouns and verbs tap into mental models of matter and causation.
Like Terry, I'm not saying I'm right and you are wrong,for what do I know about anything including time travel, space, energy, matter ,causation,etc. I'm not a scientist, I just read about science and other interesting subjects.
I have a shirt, on it, it reads, "Think, it's not illegal yet." Certainty, topics like this one that Terry has posted and all of you have responded to, gives us pause and makes us think....I think.
Blueblades