The Big Bang theory

This is the cutest post I have ever seen. You kind of remind me of...



I guess what you are trying to get at is perhaps discussing what happened prior to the big bang, the conditions that enabled the arrow of time and the universe as we experience and there are a number of cosmological theories. I am fond of Alan Guth' multiverse theory of inflation and to try and briefly explain it, it is the idea that the universe is infinitely expanding because the density of the gravitational field remains at a constant. This stretching is called 'repulsive gravity' namely that there is a negative pressure that pushes against a positive three-dimensional field though the energy is almost at 0, working in uniformity to subsequently push exponential expansion far greater than its capacity for decay; during the process of decay in certain region, conditions like that of the big bang form pockets of new universes, thus making our universe one of multiple universes in an eternal stretch of fields.

In relation to the big bang, everything is possible. I would say every hipotesis is correct, because the singularity is a mathematicaly impossibility. So the tool to perceive the universe we call reason, has no place here. So let us fantasize awayyyyyyy....

Quoting The outlaw Josey Wales

...what came first the chicken or the egg and of course the egg evolved...

Chicken or the egg? Neither. It was the fish! :D

Quoting oranssi

I would say every hipotesis is correct, because the singularity is a mathematicaly impossibility.

The idea of a singularity is absurd. That everything, essentially, came from nothing – defies all logic. I would like to hear why it is mathematically impossible?

Reply to Thinker I'm not an Astrophysic or theoretical physic, but from what I understand, the laws of physics we know nowadays don't apply in the initial singularity of the bigbang. Applying the quantum mechanics knowledge and unifying it to the general relativity gives an equation with an impossible result, like 0=infinite. I saw it in a Michiu Kaku documentary that I tried but cannot find.

Also, why do we expect that logic can explain everything? I see logic just as another instrument to perceive the things around us. Might be other mechanisms that Nature might evolve in 100 million years to perceive the Universe. Who Knows?

Quoting Thinker

The idea of a singularity is absurd. That everything, essentially, came from nothing – defies all logic. I would like to hear why it is mathematically impossible?

The idea of a singularity says no such thing. It is simply a point where the mathematics no longer yields a meaningful result. The tangent function for instance has regular singularities. That is not a statement that something is coming from nothing.

Quoting noAxioms

The idea of a singularity says no such thing.

Is a singularity a infinite density and temperature at a finite time in the past?

Quoting Thinker

Is a singularity a infinite density and temperature at a finite time in the past?

No, A singularity is a point where equations do not yield meaningful results. The singularity is a reference to the physical one of which you speak, and no, density and temperature are effectively meaningless at that point. There is no temperature without space to define motion. There is no meaningful density without nonzero mass and the universe has a net total mass/energy of zero. It is only at other points where there is variance and velocity that these measurements become meaningful.

My knowledge of inflation theory is limited. I do not know if there is meaningful classic distance and temperature during the inflation period, or if our inflation bubble is posited to initially be a dimensionless point. Most classic physical measurements do not have meaning during that first picosecond or so any more than they do beyond the event horizon of a black hole (another singularity).

Quoting noAxioms

Most classic physical measurements do not have meaning during that first picosecond or so any more than they do beyond the event horizon of a black hole (another singularity).

We have no idea a black hole is a singularity. Maybe it is a big drain hole into another universe? To say a black hole at its core is infinitely dense and hot is weak speculation at best. To suggest that infinite density and temperature ever existed (anywhere or time) is speculation as well. The drain hole sounds more plausible than infinitely dense.

Quoting Thinker

We have no idea a black hole is a singularity. Maybe it is a big drain hole into another universe? To say a black hole at its core is infinitely dense and hot is weak speculation at best. To suggest that infinite density and temperature ever existed (anywhere or time) is speculation as well. The drain hole sounds more plausible than infinitely dense.

Didn't say the center of it. I referred to the event horizon, a place where our classic rules of time and space do not work out to the usual values. Not sure if there are any infinities there, but the geometry rotates and time becomes negative and strange relations like that.
Sure, there's another singularity at the center, but that one really stretches the typical definitions of existence and again, doesn't seem to have a meaningful value that can be interpreted as temperature.

Quoting noAxioms

Sure, there's another singularity at the center, but that one really stretches the typical definitions of existence and again, doesn't seem to have a meaningful value that can be interpreted as temperature.

Ok - you have been there, so I will take your word for it.