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The Schwarzschild Radius (R) is proportional to the mass M of the structure in question, and not its density. Let's suppose that the R(sun)=2 km for the sake of argument. And further let's suppose that if an amount of matter equal to our sun - M(sun) - is confined within a 2 km radius, it can never escape the confines of the black hole it is now within (by definition).
In the very early universe, say after .001 second, the main inflationary phase has ended. At this point the radius of the universe is on the order of perhaps 300+ km in radius. Every volume is much more dense than the sun. This doesn't matter, because the Schwarzschild radius of the entire universe is quite large and does not confine the hot expanding matter/energy of the young universe. Since the universe is expanding, but the total mass is essentially constant, density is dropping rapidly.
But at some point as the average denisty is dropping, subspaces containing matter equal to M(sun) approaches a size equal to R(sun). After all, today the average mass of a volume of space with a radius of 2 km is much much less than the M(sun).
So why didn't almost every bit of matter disappear into many black holes when this happened? I know that many black holes DID form during this period and these are now the centers of most galaxies. But it seems like almost every bit of matter should have ended up confined to one black hole or another, and therefore there would be little left of the universe for us to see today. Why isn't that the case? I would expect that we would live within a black hole of 2 km in size and seen nothing of the rest of our galaxy.
But we aren't. What happened?
In the very early universe, say after .001 second, the main inflationary phase has ended. At this point the radius of the universe is on the order of perhaps 300+ km in radius. Every volume is much more dense than the sun. This doesn't matter, because the Schwarzschild radius of the entire universe is quite large and does not confine the hot expanding matter/energy of the young universe. Since the universe is expanding, but the total mass is essentially constant, density is dropping rapidly.
But at some point as the average denisty is dropping, subspaces containing matter equal to M(sun) approaches a size equal to R(sun). After all, today the average mass of a volume of space with a radius of 2 km is much much less than the M(sun).
So why didn't almost every bit of matter disappear into many black holes when this happened? I know that many black holes DID form during this period and these are now the centers of most galaxies. But it seems like almost every bit of matter should have ended up confined to one black hole or another, and therefore there would be little left of the universe for us to see today. Why isn't that the case? I would expect that we would live within a black hole of 2 km in size and seen nothing of the rest of our galaxy.
But we aren't. What happened?