Time may well be illusory. Or, it may have no direction. Equally, the space-time continuum, relative as it is to homo sapiens sapiens, also, as a practical matter, is illusory &, well, relative. We notice these things, i. e., we think about them, because we can and because we need to believe that anything that may affect us needs to be analyzed, ad nauseum, or even more so. Astro-Physicists and Cosmologists need something to occupy their TIME; they need to feel secure about their place in the biggest possible picture human society . Also, and perhaps more telling, if we should ever understand any and all branches of physics; if we should ever be able to fully utilize these things which are now only topics for discussion and conjecture, the stuff of science fiction (or more of it) could be within our reach. Imagine if space-time continuum actually meant something we could manipulate, if only in small ways (whatever those might be...). Admittedly, this is mostly speculation. But, thinking about it, that is how many of our realities arrived. They grew out of speculations. And, surely, as philosophers, we speculate daily. Jumping outside of the space---this is what we are all about...
The only things we can never know are those about which we have no curiosity. A totality of the circumstances...or something like that.

This morning, I was getting coffee from my favored quick stop. I saw an individual whom I recognized as having made some news, locally, with research into the notion of time travel. I asked him how his work was going: had he figured out the old space-time continuum conundrum? He said he (and unnamed collaborators) were getting close; mentioned something vague about an upcoming press conference; and also said the Australians were making headway but were 'way behind what we are doing'. Now, I'm not one to pooh pooh scientific progress: I like to think I might know it when I see it...sometimes even occasionally predicting a thing or two, myself. But, this man has been kicking this around for a number of years. He is animated when talking about time travel, one might say: driven. I know no one else who knows him and most people of repute, with whom I have spoken, roll their eyes some when his name is mentioned. I'll not mention his name here, inasmuch as my revelation about him is not glowing and might even be considered insultatory.

But, allow me to be clear. He was knowledgeable regarding the likes of Sean Carroll; the late Stephen Hawking and others. I sincerely hope he is on to something (whether on his own or with collaboration). Think of it: time travel! Wouldn't that be grand? Sure. But, I won't take any bets on it. Just yet. Oh, he did mention that he had little time for philosophers---thought that they spent far too much time arguing with one another; that their professed search for truth was a con. They ARE a fussy lot sometimes. But, aren't we all?

It's the speed at which space is created by bending it out of itself. It's an expanding bubble created by relevance.