Did the Universe's Components Emerge Simultaneously?

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In summary, the universe is believed to consist of three main principles: space-time, physical matter/energy, and the physical laws that govern them. However, we do not currently know the order in which these three things came into existence. There are various theories, such as Loop cosmology, that suggest that time and space may have existed before the "big bang" and that the universe may have undergone a rebound or bounce, instead of a traditional big bang. This area of research is known as quantum cosmology and is continuously evolving with new theories and models being proposed.
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JeremyL
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I have read in various places that the universe essentially consists of three principles: space-time, physical matter/energy, and the physical laws that govern the first two.

Do we know the order in which these three things came into existence?

I'm confused by the role of the physical laws. Are these laws necessary for the universe to exist? Do stars form into a barred spiral galaxy structure solely because of the physical laws that govern them?
 
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JeremyL said:
...

Do we know the order in which these three things came into existence?
...

The simple answer is NO, we do not.

I speculate that within your lifetime, or anyway the lifetimes of some of us here, we may be able to rule out the possibility that any of those three things first came into existence at the time of the "BB" or start of expansion. That is, we may have a model, supported by observational evidence, in which time runs back to conditions before "BB" without the model breaking down.

We already have several models that go back before start of expansion. One or more of them are worked out in enough detail that one can try to make testable predictions: e.g. the way expansion starts may leave an imprint on the microwave background which can be looked for, as a test, given the kind of observational instruments one can expect to be launched in the next decade or two.

As an illustrative example, perhaps the simplest such model (involving minimal extra assumptions) is Loop cosmology, in which gravity is quantized and turns out to repel at extreme density so there is a BOUNCE. A universe like ours, collapsing, reaches such high density that it rebounds and enters a natural period of inflation.

So in that model, which can be both run in computer simulations and solved using equations, there is no beginning of time, spatial geometry, matter, or physical law. The smooth rebound that replaces the "big bang" is only the start of expansion, not of the other more profound awesome stuff you mentioned. Yes something happened 13.7 billion years ago, but the really Big Questions are put off---shoved back in time for possible later consideration. I guess you could say that instead of being "postponed" the Big Questions are "pre-poned."

The general research area here is called "quantum cosmology" QC. (Quantizing the cosmological model tends to make the singularity go away---apparently it was an artificial result of not using quantum theory---and often makes time continue on back further into the past, in one way or another.)

Although the research papers are mostly too technical, some readers might want to check out the titles, and some of the summaries at the beginning, so I will give a recent QC search link. This will get both Loop QC AND OTHER QC, and is restricted to papers appearing 2009-present.
http://inspirehep.net/search?ln=en&...m=&d2y=&sf=&so=a&rm=citation&rg=10&sc=0&of=hb

The search currently gets 288 recent QC papers which is too many but I have it ordered by the number of times papers were cited by other research, so you tend to get the most read and referred-to ones first. Looking over the first 20 or so will give an idea of what is happening in the QC field nowadays.
Most of the top 20 listed will have some kind of REBOUND replacing the big bang, something that has gotten a growing number of researchers interested lately.
 
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FAQ: Did the Universe's Components Emerge Simultaneously?

What is the universe?

The universe is the entirety of space, time, matter, and energy that exists. It includes all planets, stars, galaxies, and other forms of matter and energy.

How did the universe begin?

The most widely accepted theory for the origin of the universe is the Big Bang theory. This theory suggests that the universe began as a singularity, a tiny, infinitely dense and hot point, approximately 13.8 billion years ago. It then expanded and cooled, eventually forming the structures we see today.

What is the purpose of the universe?

The purpose of the universe is a philosophical and subjective question that has been debated for centuries. Some believe that the universe has a specific purpose, while others believe it is random and without purpose. As scientists, we focus on understanding the laws and forces that govern the universe, rather than its purpose.

Is the universe infinite?

We do not currently have a definitive answer to this question. According to the Big Bang theory, the observable universe has a finite size, but it is constantly expanding. Some theories suggest that the universe may be infinite, but this is still a topic of debate and further research.

Are there other universes?

There are various theories and hypotheses about the existence of other universes, also known as the multiverse. Some theories suggest that there may be an infinite number of universes, while others propose the existence of a limited number of parallel universes. However, there is currently no concrete evidence to support the existence of other universes.

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