How can space or the universe be both infinite and expanding at the same time?

It is a scientific fact that there is no end to the universe. Hence, it is infinite. But, according to new cosmology theories, space is constantly expanding too. So, if it is already infinite then how can it expand more?

By using the word “expanding,” we’re given the assumption that the universe must be expanding into something, from a central, fixed point. To explain it in a somewhat concise manner, you have to realize that space isn’t something that is just there and stellar objects are just moving throughout it. It actually bends and stretches.

To understand this phenomenon, let us consider a real-life example. Take raisin cookie dough; consider the dough as space, and raisins as the galaxies.  Now, if you stretch this dough, the raisins will move apart similarly to what happens in the space.  

Without any way to leave our little raisin, there is no way to see the “end” of the dough – so, if we assume that the universe is truly infinite, then it simply doesn’t have anything to “expand” into. Using a mathematical analogy, you have a series of whole integers that start with one to infinity. If you took every number and multiplied by any factor, the numbers in your series have stretched away from each other; yet the list hasn’t expanded. You still have a series that progresses from a number to infinity.

Big Bang Theory

The expansion of the universe is theorized by the Big Bang theory, which states that the development of the universe began from a big blast or bang, which broke the energy into matter and scattered particles of the matter. These particles became the stars and planets that form the universe. And it is hypothesized that these particles are moving away from each other into an unknown realm. The consequence of the big bang produced a lot of energy, which probably knows no ends, and it is that energy which is causing the particles to move away still, millions of years later. 

Similarly, expansion of the universe is nothing but a concept of energy change. When it expands, it pulls the galaxies away from one another. Due to this, the distance between them is increased, just like the cookie dough. 

Is The Expansion Invisible?

The unknown realm is what we are talking about here. The universe is expanding because the distance between the so-called particles is increasing, but where does this expansion end, no-one really knows.

Does the universe have any boundaries, or is it just expanding into itself, without any boundaries or limitations?  For now, it can be stated that the expansion of the universe is intrinsic, it does not expand into anything, and it does not need any space to expand into, it is just expanding. We know this because the distance between any two points in the universe, the points being the solid bodies that are planets and stars, is increasing day by day. Thus, suggesting that they are moving away from each other, the stretch of the universe. 

Following are some helpful materials that might answer some of your questions related to space and time.

Where to Buy
Expanding Universe. Photographs from the Hubble Space Telescope
Discovering the Expanding Universe
Marvel The Expanding Universe Wall Chart


Expanding Universe. Photographs from the Hubble Space Telescope

The Hubble telescope has changed the way we look at outer space. When it was invented, it helped scientists to solve major mysteries of cosmology. On its 25th anniversary, TASCHEN released this book with ultra HD pictures of space taken by the Hubble telescope.

This book debunks a lot of astronomy questions, like dark energy and black holes. These photographs are for the curious ones who want to see what space looks like and how it is expanding. Now, every space lover can have it and admire the space from their homes.

Discovering the Expanding Universe 

The book claims to be for the common layperson who wants to know and understand the secrets of the universe. It starts by explaining the beginnings of modern cosmology and Einstein’s theories that lead to modern concepts.

Marvel the Expanding Universe Wall Chart 

If you want to see the universe and how big it is, this chart is for you. It starts from a page and opens up to 12 feet, showing you how the universe expands in as realistic a manner as possible. It opens up to you the expansion of the universe.

The interesting thing about this wall chart is that it consists of more than 300 Marvel Comics characters put together to entertain you.