Amazing. All those brilliant physicists out there, and you’re the only one who can do the math.
The math is why physicists feel compelled to invent “dark matter” and “dark energy” from whole cloth...for the physics equations can’t show an accelerating universe without such artificial constructs.
...but anyone who believes in Einstein’s work should disregard “dark matter” and “dark energy” as superfluous constructs because sharply edged space/time boundaries to our Universe explain why matter accelerates as it approaches the edges.
And that explanation needs no such nonsense like “dark matter” to explain unseen gravity.
Or put another way, anyone who believes in “dark matter” and/or “dark energy” is essentially saying that Einstein was wrong about curved space/time.