Man's quest for making sense of his surroundings has led him to innovate many things which includes giving names to celestial bodies, writing manuscripts about it and naming the entire thing as Universe. but is it really called universe?, some hold the opinion that it should be called multiverse, not Universe. do they have a point?, likely. from hunter, gatherer tribes sheltered in caves, armed with pointed rocks for protection from wild animals, looking at the night sky with full of celestial bodies bewildered - To the modern man who made satellites, sent them to outer space to orbit around the planets which enabled countries, Governments & corporations, manage their operations to the highest degree of accuracy, The whole journey has been Phenomenal.
The transition from Barbarism to tillage involved a lot of thinking, Thinkers, Philosophers & Scientists from all ages have explained how the whole thing exists & operates. from Geo-centric theory to Helio-centric theory, from flat earth to elliptical Spheroid many learned men have speculated about the size & shape of the whole thing and the Earth (the human's home) at large with mathematical precision. We (Human) seem to have largely agreed upon the shape of earth to be Round though there are other theories that suggest that the earth is not perfectly round. when viewed a files miles above from the surface of the earth all anyone can see is Peaks & Valleys, Oceans & Mountains, stream of water flowing from one place to another, Giant trees, cities and a few flat lands made by man through Tillage.
How arrogant of man to place a perfect round shaped object on his desk, call it a globe, explain it to the people around him that this is the whole Earth. from evolutionary stand point a living creature (Human beings included) will make sense of the world better as it gets stronger. the ones which co-operate with the strong are protected and the ones which repel the strong perish. this has been the rule of Nature. so the knowledge about the whole thing, the celestial bodies and Earth comes either from the Strong which survived the nature's test or the secondary strong which have co-existed with the Strong. Does it mean that the weak have to suffer? Can't they wonder about the outer space, the celestial bodies and make their own speculation about them. that's where the imagination comes into picture. As Albert Einstein rightly said "Knowledge is limiting because it is only learning about the existing set of rules. while imagination lets us thrive to know all that is there was and ever will be.
In our Academics we hardly speak of 4th dimension of the Physical world but scientists who use imagination as their tool proposed theories such as String Theory, M-Theory according to which physical space exists in 10-11 Dimensions (https://en.wikipedia.org/wiki/M-theory) which is not widely accepted by the majority off-course. Even the senses with which we comprehend the surroundings are thought to be 5, but deep studies tell us there are as many as 21 Senses (https://toistudent.timesofindia.indiatimes.com/news/features/humans-have-21-senses/3216.html). the starting point of this knowledge is also imagination.
Finally the thought of comprehending & calculating the universe comes from the hypothesis that it is Finite. but when it is Infinite how would one be able to describe the whole thing mathematically. it is very harmful to comprehend the outer space based on the finite hypothesis. Let everyone's imagination run wild and make sense of the world around them in their own Way. Because it is not Universe, it is Multiverse.
Note: Since the article is about calling it multiverse not universe, I used the word the whole thing in place of Universe.