I have no formal training in this field. What I do know I have garnered from reading various publications or watching videos. I understand that the balloon analogy isn't popular, partly because once you say balloon people have trouble not thinking about a balloon. What I intend here is to lay out a visualisation of the balloon analogy but with the twist of space being a flat plane before the Big Bang. If this model has been proposed before I apologise. Imagine a flat sheet, similar to a bed sheet, floating in the air that draws in when pressed upon by a force. This stays within Einstein's view of gravity causing space to curve around an object. It has no edges and extends into infinity. At the moment of the Big Bang, all matter in the Universe presses down on space and depresses it. Every entity that is gravitation bound to each other presses on the same area of space and goes into the same depression of space. There are many of these individual depressions and each one causes space to draw downward. At this point you should imagine space as similar to a folded sheet of paper into an accordion and viewed from the edge like this ( ------- becomes --vvv--). The top of the wave is the original surface of space while the bottom is the depression caused by matter. As you can see, this makes all matter appear close to each other. But, as you pull on the edges of the sheet, the distance between the gravitation bound entities get further away from each other. Also, the fact that each depression is not to the same depth can be assumed, meaning some areas should return to near flatness before others. An object, such as a photon, does not travel up the line of space and back down between two gravitation bound groups, but takes a straight path from one to the other. As space returns to flatness, this path becomes longer. So, more observed space is realised without the need for space to have stretched and instead it was gathered in and depressed. All matter would 'appear' to have been in a small area, with some (perhaps only massless) matter able to travel between the depressions directly while gravity cannot do so. Or, the force pulling space back to flat is slightly greater than the gravity. This is causing the expansion to happen more rapidly as gravity is reduced by greater distance between unbound areas and causing less resistance. Anyway, if I don't stop here, I will be going into a lot of speculation and hopefully I have already demonstrated the visual effect I sought to impart. I have edited the post before posting to remove any blatant speculation. I found it hard not to insert some in the course of writing. I did leave the gravity speculations as I can see those would need be directly addressed. If the entire post is viewed as speculation I apologise and will understand if it is removed.