The phrase "an equally vast" is correct and usable in written English.
It can be used when comparing two things that are similar in size, extent, or degree.
Example: "The ocean is an equally vast expanse as the sky above it."
Alternatives: "a comparably vast" or "a similarly vast".
Hold up, though, because Matthew fortuitously appears to be inheriting an equally vast fortune at the same time (that's the second time he's done that, isn't it?).
With prices from $40 to $4,000 and an equally vast range of features, a digicam is as personal a gift as a car, a computer or underwear.
Like "Apocalypse," an equally vast Furnas painting, which was displayed in the window of Lever House, on Park Avenue, last fall, this one's dominant color would be a dark, visceral red that looked startlingly like blood.
By nominating a range of drugs as illegal, society has created a rod for its back; it has potentiated a criminal industry and assumed the vast expense of policing it, thereby creating an equally vast public problem where before there had been personal and medical problems only.
It comes sporting a 3G wireless connection like the Kindle, the same price as the Kindle, but also the two screens and an equally vast eBook store.
Conservatives who see an equally vast liberal conspiracy are dismissed even among their friends as trapped in ideological fever swamps from which they rarely escape.
It's a question that's amplified to a worldwide scale when he's confronted by cameras, sees himself on television, and is recognized and hailed as a public hero while enduring spasms of self-questioning and self-doubt that are sparked by an external — and equally vast — source of doubt: the federal government.
Nothing was beneath his regard, and no one exceeded his vision for art as a kind of alternative planet, equally vast in scope and scale.
Three years ago, for the opening of Tate Modern, one of Long's huge mudworks and a circular stone floor sculpture were housed in the same room as one of Monet's equally vast water-lily paintings in a section called Landscape/Matter/Environment.
At PCR, portraits are hung alongside landscapes and huge abstractions (the traces of dust on processing paper) take their place beside equally vast studies of ordinary things, like a weed standing tall in his unkempt garden.
But the government's construction plans have not dovetailed with its equally vast energy plans.
