In addition, quoting from ''The Big Bang and the Expansion of the Universe'', space and time were created in the Big Bang. At the beginning of the universe, the space was completely filled with matter. The matter was originally very hot and very dense and then expanded and cooled to eventually produce the stars and galaxies we see in the universe today. Although space may have been concentrated into a single point at the Big Bang, it is equally possible that space was infinite at the Big Bang. In both scenarios the space was completely filled with matter which began to expand.

For the rest you may visit http://www.atlasoftheuniverse.com/bigbang.html.

No.it;s not i guess, because space is not absolute. space and time are mixed together as a single quantity called spacetime. if space became infinite in none of a second that means it does not care about time which is a contradiction to modern theories.

i think nothing can be said with surety what happened at the time of origin until we have a complete theory that gives a better understanding.  

Dr. Dogas,

I am an agriculturist and I have not the appropriate theoretical background to answer your question. Please allow me to express some thoughts which you may find (or not) interesting.

To my knowledge, from a wide point of view, Big-Bang is a widely accepted theory but only a theory. This theory, as each other theory, has merit and reflects an attempt of humankind to go further.

In this point, please see the interesting question of Prof. Ruiz Espejo ''How far do the experimental sciences arrive?'', here, in RG net and the relative discussion, which, in my opinion, have a relation with your question.

Personally, I believe that the aforementioned theory will remain theory, reminding humans that the limits exist.

Kind Regards

I came across an interesting relevant article to the main question of the thread titled ''The Big Bang Wasn't The Beginning, After All'', by Ethan Siegel, from which I quote: Three specific things you would expect from the Big Bang didn't happen. In particular:

1. The Universe doesn't have different temperatures in different directions, even though an area billions of light-years away in one direction never had time (since the Big Bang) to interact with or exchange information with an area billions of light-years in the opposite direction.

2. The Universe doesn't have a measurable spatial curvature that's different from zero, even though a Universe that's perfectly spatially flat requires a perfect balance between the initial expansion and the matter-and-radiation density.

3. The Universe doesn't have any leftover ultra-high-energy relics from the earliest times, even though the temperatures that would create these relics should have existed if the Universe were arbitrarily hot.

For more you may look at https://www.forbes.com/sites/startswithabang/2017/09/21/the-big-bang-wasnt-the-beginning-after-all/#6a741cf855df.

In addition, quoting from ''The Big Bang and the Expansion of the Universe'', space and time were created in the Big Bang. At the beginning of the universe, the space was completely filled with matter. The matter was originally very hot and very dense and then expanded and cooled to eventually produce the stars and galaxies we see in the universe today. Although space may have been concentrated into a single point at the Big Bang, it is equally possible that space was infinite at the Big Bang. In both scenarios the space was completely filled with matter which began to expand.

For the rest you may visit http://www.atlasoftheuniverse.com/bigbang.html.