Big Bang Theory?

Question

"BIG BANG THEORY" is one of the largely accepted probability for the birth of our universe. But what would have been the situation before the big bang took place?

What substance/what matter was there which eventually caused "big bang"?

If there was anything then, how long was it there ?

Answer 1

Time is just another coordinate of spacetime, so it has to unfold together with the other dimensions. Time is created with the rest of space; there was simply no "before". There was no "instant" of creation and there was no "location" for the primordial explosion either. The center was everywhere. It still is.

A geometrical analogy might help: Think of the surface of a sphere and imagine latitude is "time". There's nothing north of the North Pole, is there?

This analogy with a sphere has other nice features. In particular, the North Pole is not very different from nearby points; it's just an artifact created from the way we measure things. So too, the "instant" of creation is not well defined; it depends on the speed and location of the vantage point from which the (theoretical) mesurement is made. All of this is without even considering the quantum aspects which nobody really understands (yet?). Does this blow you mind? Well, it should. It blows everybody's mind.

Concerning, the "stuff" the Universe was made from, the answer is also weird... The key remark is that gravitation has more negative energy when everything is packed tight. Think about everyday experience: energy is released when an object is dropped, so there's less energy (more "negative energy") when the Earth and the object are closer together. At the scale of the entire Universe, the numbers are mind-boggling: The positive energy in the Universe today (the energy of radiation and matter according to E=mc^2) seems to balance exactly the negative energy of gravitation. Therefore, it looks like the Universe could have been created from zero energy, from absolutely nothing!

Come to think of it, it MUST have been so, or else how would you explain the "manufacture" of the original stuff itself? This framework makes the Universe explainable (in principle, at least) without violating physical laws. Ultimately, we can hope to be left with only one question: "Why?" or "What caused it?" That last question, however, is not a scientific one (no matter how interesting it might be).

Answer 2

A good question, though more for the physics/astronomy crowd...
The BB is a "theory", which BTW, is the highest honor you can bestow upon a scientific idea.

But the question is: what happened B4 the BB? This is where other theories come in. It's not the job of the BB theory to explain what happened B4 the BB - so, not knowing this yet is not a criticism of the BB theory.

Also, it should be obvious that invoking some kind of god to explain things will get us nowhere.

So, what are the hypotheses about pre-BB conditions?
1) Some say the question is meaningless - that there was nothing B4 the BB, that both space and time as we know them started at the BB.
2) Some say the BB was just the latest in a series of BB/Big Crunch cycles that have been going on forever.
3) Some say that there are many other dimensions of space-time that exist outside the realm of what we can observe and that our BB was just an explosion of our dimensions
4) Maybe the BB that formed our universe was one of many events that form other universes that we don't know about, either because they are in other dimensions, or other times, or other places...

I don't know - maybe take some LSD and try to come up with some other ideas...

Answer 3

How annoying when people just quote that much Wiki and don't even answer the question...

The question was what "existed" BEFORE the BB, not the exact process of it happening.

Of course no one KNOWS the answer to these questions... I'm no astrophysicist but I like to read. Some think the universe is in a neverending state of expanding and contracting, and what we call the big bang is just the beginning of this latest expansion phase.

Or, maybe our universe is just a bunch of matter that was sucked into a giant black hole in an even larger universe and all that is here is what was spat out of the other side (that being the "big bang").

Or maybe the big bang occured when we were all sneezed out of the nose of a being called the Great Green Arkleseizure. (much love and respect to the Great Douglas Adams)

Answer 4

First of all you should remember that the Big Bang is only a theory. It best fits what we know about the universe.

As to what was before the Big Bang, that is totally and absolutely unknown. There are ideas and concepts, but not a single shred of hard evidence to support any of them.

Answer 5

Its a good question and exact answer unknown so far.
It is more of a energy-matter transformation but then this is not the final answer. We really do not know the origin of matter and universe.
thnks

Answer 6

We cannot know because if you view this theory as a tail then up till that point we can guess or try to follow the "road" but then it stops and we get nothing no more clues to follow or anything.

Answer 7

sounds like a great question that I am sure its answer is NOT in the Bible since it offers no data....

demand evidence

for example [ braxton_paul ] calls it just a theory--course gravity is just a theory and I bet he thinks it exists...

theory in science is a very special term...course most people treat it as an idea

Good Luck

Answer 8

The earliest phases of the Big Bang are subject to much speculation. In the most common models, the universe was filled homogeneously and isotropically with an incredibly high energy density, huge temperatures and pressures, and was very rapidly expanding and cooling. Approximately 10−35 seconds into the expansion, a phase transition caused a cosmic inflation, during which the universe grew exponentially.[22] After inflation stopped, the universe consisted of a quark-gluon plasma, as well as all other elementary particles.[23] Temperatures were so high that the random motions of particles were at relativistic speeds, and particle-antiparticle pairs of all kinds were being continuously created and destroyed in collisions. At some point an unknown reaction called baryogenesis violated the conservation of baryon number, leading to a very small excess of quarks and leptons over antiquarks and anti-leptons—of the order of 1 part in 30 million. This resulted in the predominance of matter over antimatter in the present universe.[24]

The universe continued to grow in size and fall in temperature (and hence the typical energy of each particle was decreasing). Symmetry breaking phase transitions put the fundamental forces of physics and the parameters of elementary particles into their present form.[25] After about 10−11 seconds, the picture becomes less speculative, since particle energies drop to values that can be attained in particle physics experiments. At about 10−6 seconds, quarks and gluons combined to form baryons such as protons and neutrons. The small excess of quarks over antiquarks led to a small excess of baryons over antibaryons. The temperature was now no longer high enough to create new proton-antiproton pairs (similarly for neutrons-antineutrons), so a mass annihilation immediately followed, leaving just one in 1010 of the original protons and neutrons, and none of their antiparticles. A similar process happened at about 1 second for electrons and positrons. After these annihilations, the remaining protons, neutrons and electrons were no longer moving relativistically and the energy density of the universe was dominated by photons (with a minor contribution from neutrinos).

A few minutes into the expansion, when the temperature was about a billion Kelvin and the density was about that of air, neutrons combined with protons to form the universe's deuterium and helium nuclei in a process called Big Bang nucleosynthesis.[26] Most protons remained uncombined as hydrogen nuclei. As the universe cooled, the rest mass energy density of matter came to gravitationally dominate that of the photon radiation. After about 380,000 years the electrons and nuclei combined into atoms (mostly hydrogen); hence the radiation decoupled from matter and continued through space largely unimpeded. This relic radiation is known as the cosmic microwave background radiation.[27]

Over time, the slightly denser regions of the nearly uniformly distributed matter gravitationally attracted nearby matter and thus grew even denser, forming gas clouds, stars, galaxies, and the other astronomical structures observable today. The details of this process depend on the amount and type of matter in the universe. The three possible types of matter are known as cold dark matter, hot dark matter and baryonic matter. The best measurements available (from WMAP) show that the dominant form of matter in the universe is cold dark matter. The other two types of matter make up less than 20% of the matter in the universe.
The universe today appears to be dominated by a mysterious form of energy known as dark energy. Approximately 70% of the total energy density of today's universe is in this form. This dark energy causes the expansion of the universe to accelerate, observed as a slower than expected expansion at very large distances. Dark energy in its simplest formulation takes the form of a cosmological constant term in Einstein's field equations of general relativity, but its composition is unknown and, more generally, the details of its equation of state and relationship with the standard model of particle physics continue to be investigated both observationally and theoretically.

The Big Bang theory depends on two major assumptions:

The universality of physical laws
The cosmological principle—the universe is homogeneous and isotropic
These ideas were initially taken as postulates, but today there are efforts to test each of them. For example, the first assumption has been tested by observations showing that largest possible deviation of the fine structure constant over much of the age of the universe is of order 10-5.[28] Also, General Relativity has passed stringent tests on the scale of the solar system and binary stars while extrapolation to cosmological scales has been validated by the empirical successes of various aspects of the Big Bang theory.[29]

If the large-scale universe appears isotropic as viewed from Earth, the cosmological principle can be derived from the simpler Copernican principle, which states that there is no preferred (or special) observer or vantage point. To this end, the cosmological principle has been confirmed to a level of 10-5 via observations of the CMB.[30] The universe has been measured to be homogeneous on the largest scales at the 10% level.


more on big bang and references:
http://en.wikipedia.org/wiki/Big_Bang

Answer 9

and here lies another flaw in the big bang theory that cannot be explained

Answer 10

Here is another most asked question. Please search within the answers already provided.