At this stage, the scientific community does not have a clear understanding of the origin of the universe. For example, the Big Bang model is just a hypothesis model. It is widely circulated because it can explain most phenomena. In fact, the Big Bang model There are also phenomena that cannot be solved by the explosion model. The current scientific community is working hard to improve this model or establish a new universe model. The authenticity of the Big Bang model has yet to be determined!

Regarding your questions, first of all, they are based on the recognition of the Big Bang model of the universe. Marx said that time is one-dimensional, without beginning or end; The most small and innocent. These seem to be contrary to the Big Bang. (But Marx is not necessarily old, right?)

If you have to answer your questions, they are just personal opinions.

1. The singularity is unstable. Any slight disturbance will destroy this balance, and disturbances are almost everywhere. There is constant thermal motion in our current world. The energy of the singularity at the origin of the universe is so large and yet so small (infinitely small) that it must be an extremely low-entropy (highly ordered) state. According to the laws of thermodynamics, it is an extremely unstable state. (The key is that all physical laws may fail in the singularity state, so this explanation may not be correct.)

2. The universe is currently in an expansion state. The expansion and contraction of the universe depend on the critical density of the universe. Specifically You can go to the website to take a closer look, I won’t go into details here. But to give us a hint, the initial energy of the universe may have come from the collapse of the universe. In other words, the universe is experiencing a state of expansion-gt; collapse-gt; expansion-gt; collapse...

3. Two opinions (two ideas are more appropriate). The first one can be found out by looking at the answer to question 2; the second one says that there was neither time nor space before the singularity.

I hope everyone can correct each other.

Give me some information. It is actually Baidu Encyclopedia, which should contain the mainstream views in the scientific community.