# Big Bang Implosion

## Main Question or Discussion Point

Where there is explosion, there is usually a concomitant implosion. If the Planck length, L*, demarks an original radius for the cosmos, a collapse therefrom, symmetrical to the big bang expansion of spacetime occurs with the conservation of momentum. This "Big Crush" is omnipresent, sub-Planck length and suggests a connectiveness between all matter. Our reality may exist in mirror image, reflected through the primordial surface of separation, L*.

## Answers and Replies

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Danger
Gold Member
I'm afraid that I don't really understand any of that. (My fault, not yours; it's not something that I've been exposed to before.) The aspect that strikes me as being maybe a little off is that I don't think that the BB can technically be considered an explosion. It's more like a balloon inflating, since it's not exploding into a pre-existing volume. No mass or energy is being ejected from the source; the source itself is just expanding.

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JesseM
Loren Booda said:
Where there is explosion, there is usually a concomitant implosion. If the Planck length, L*, demarks an original radius for the cosmos
The Planck length isn't supposed to be the original radius of the cosmos, if the universe has flat or open curvature (and the simplest topology) then the cosmos was infinite at all times past the Planck time, and even if the universe is finite in size, I think all you can say is that as you approach the Planck time the density of matter/energy approaches the Planck density. See this thread for more on the significance of the Planck density/Planck length, and the last section of my first post on this thread about why you shouldn't picture the Big Bang as an explosion of matter in a preexisting space, and the difference between closed, flat and open curvature.
Loren Booda said:
a collapse therefrom, symmetrical to the big bang expansion of spacetime occurs with the conservation of momentum. This "Big Crush" is omnipresent, sub-Planck length and suggests a connectiveness between all matter.
If the density of matter/energy is high enough the universe could collapse in a "Big Crunch" at the end of time, but current observational evidence suggests it will expand forever. See this page for a little more info on how the density of matter/energy, as well as something called the "cosmological constant", determine the ultimate fate of the universe according to general relativity.
Loren Booda said:
Our reality may exist in mirror image, reflected through the primordial surface of separation, L*.
I don't understand this part at all--what is L*? What is it separating?

Phobos
Staff Emeritus