Is spacetime wholly a mathematical construct and not a real thing?

Speaking of what I understood, spacetime is three dimensions of space and one of the time. If we now look at the general relativity, spacetime is generally counted as a 'tissue'. So my question is whether spacetime is real or just a mathematical construct to understand different things. And if that is a mathematical thing, what does that mean with its distortion / bowing?

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What's a good score slash number of points for an artical to be worthy of trust? The Left has become totally unhinged. They no longer care what is Right for our Great Countrty!