No livro de L'Engle, um tesserato é um objeto de cinco dimensões. Não é um objeto físico, mas uma abstração usada para explicar um atalho através do espaço-tempo. Três dimensões lineares, além de uma dimensão de tempo, mais uma quinta dimensão para dobrar as outras quatro para reduzir os tempos de viagem.
Meg sighed. "Just explain it to me."
"Okay," Charles said. "What is the first dimension?"
"Well --- a line: ---"
"Okay. And the second dimension?"
"Well, you'd square the line. A flat square would be in the second dimension"
"And the third?"
"Well, you'd square the second dimension. Then the square wouldn't be flat any more. It would have a bottom and sides, and a top."
"And the fourth?”
"Well, I guess if you want to put it into mathematical terms you"d square the square. But you can't take a pencil and draw it the way you can the first three. I know it's got something to do with Einstein and time. I guess maybe you could call the fourth dimension Time."
"That's right," Charles said. "Good girl. Okay, then, for the fifth dimension you"d square the fourth, wouldn't you?"
"I guess so."
"Well, the fifth dimension's a tesseract. You add that to the other four dimensions and you can travel through space without having to go the long way round. In other words, to put it into Euclid, or old-fashioned plane geometry, a straight line is not the shortest distance between two points."
Fora do trabalho de L'Engle, um tesserato é a extensão natural de um cubo para quatro dimensões, não cinco.