The Big Bang and faith...
"It takes more faith to suggest the universe comes from nothing, that nothing created the energy in the universe. What started the big bang?"
Let me start out by making my purpose clear: this is not a forum post to encourage people to believe in the Big Bang and presenting the evidence for that. Other people have done that countless times, and if need be I'll make another post about that, suffice it to say if you do not accept the expansion of a multibillion year old universe, you are free to join the ranks of the less than half a percent of cosmologists that agree with your pseudoscience. (EDIT I would also like to make clear that this is not an argument for why god does not exist, as I do not feel such thing can be argued scientifically. I simply wish to make the point that the universe does not necessitate any supernatural entity, and that claiming any such entity exists is necessarily a fancy way of invoking the the god of the gaps.
What this post is for, then, is to address some questions that arise when people start talking about the Big Bang. I find that almost inevitably, we fall into the trap of trying to use intuition and "common sense" to answer questions of theoretical physics. The last time we tried to use intuition to argue matters of physics we came to the conclusions that more massive objects fall faster and that the sun and all other planets revolve around the earth. Clearly, intuition won't be very helpful here.
"What came before the Big Bang?" Many of you already know this, but to tell the truth, it's a meaningless question. We, as humans, are victim to the condition that if we can ask a question, we feel it must have some sort of answer. I posit these equally meaningful questions: "What tastes better than blue?" "What's colder than absolute zero?" "What's darker than true black?" The Big Bang was the expansion of spacetime. Not just space, but *spacetime*. This intricate weaving of our four overt dimensions unraveled following the events of the Big Bang. Time and space are defining qualities of our universe, and so long as the universe has existed, time, too, has existed.
Asking "what came before the big bang?" is akin to asking "what came before time?" It's important to realize that "before" refers to a point necessarily in time, specifically, when we say "X happened before Y," we mean "event Y occurred at a point T in time and event X occurred at point in time prior to T." To ask "What came before the big bang" is akin to asking "What event occurred in the point in time prior to time?" You are asking for a point in time yet conceptualizing a state where time does not exist. It's a meaningless question.
What are the other ramifications of this? Well, oddly enough, it means the universe has always existed.
Let's break down the semantics: "always" is a word referring to "at all points in time" or "for all time." As we established earlier, so long as the universe has existed, time has existed. Meaning, at all points in time, the universe has necessarily existed (time being a requisite constituent of our particular universe). The universe has always existed. Baffling, huh? Our human language is so inadequate for talking about the universe, where so many things fly in the face of the every-day experience our common sense evolved around.
So inevitably, the question of causality arises. Cause and effect is perhaps the thing we, as macroscopic beings, take for granted the most. If I leave my keys on my desk, I can be fairly sure that when I come back two hours later, they will still be on my desk. But this is hardly always the case, or even necessarily the case. If I were a tiny-man in a tiny-room and left an electron on my tiny-desk, I could go and come back, and, for no reason, the electron could be under the desk, in the next room, upside down, etc. The smaller our length-scale becomes, the more prominent these effects-- quantum effects-- become.
Here again we are fundamentally crippled by our feebly evolved brains. We crank things back until we get to a point where we are left to conclude that there was no space and no time, subsequently no free energy, and then it just burst into creation! For many people, this implies god. There is no law of "cause and effect" in science. The most fundamental principle of all physics is the law of conservation of energy. But how do we explain this apparent contradiction? Spacetime and free energy coming into existence seems to violate this grossly? Even then, *how* did they come into existence? Wasn't there a requisite *cause*?
We are forced to evaluate a situation wherein there is no space and no time. The mistake many people make is equating this to "nothing." Simply because our beloved four dimensions didn't exist doesn't mean there was "nothing" at all, anywhere. In fact, "nothing" is such a perverted and heuristic concept that it should be wholly abandoned when speaking of physics. "Nothing" is a term that means different things to different people, but it never truly means nothing. For cosmologists like Stephen Hawking, "nothing" simply means no spacetime geometry. For particle physicists, "nothing" can mean a vacuum, an area of space devoid of matter. In the latter case, we know that there can still exist much in a vacuum: electromagnetic and gravitational waves, dark matter, dark energy. Similarly, in the former case, lack of spacetime geometry does not mean absolutely nothing exists. It's here that we fall back on the most fundamental principles governing our universe: quantum physics.
The quantum fluctuations we (being creatures locked into spacetime) can measure directly are those that are a function of space and a function of time. It's difficult for us to imagine that any such fluctuation could occur without space and without time, yet dimensionality is but a simple property of our observable universe. There is no law that dictates that quantum fluctuations require space and time, and in fact, the manner in which quantum fluctuations evade our concepts of space and time seem to indicate that they are fundamentally divorced somehow. Indeed, this is the greatest problem in modern physics: grand unification, attempting to reconcile quantum physics with relativity. Can it be done? Possibly, but one thing is clear: relativity, our concepts of space and time, do not function on the scales that quantum physics does.
This fluctuation that is neither a function of space nor a function of time with a given energy potential is a plausible means of, for lack of a better word, "triggering" the big bang. What about the conservation of energy then? We have free energy and we have spacetime, how is energy conserved? Simply put, our observations to date seem to indicate the warping of spacetime (gravity) as described by general relativity has a negative energy which precisely cancels out the existent matter and energy in the universe. If such is the case (which I believe is the currently accepted hypothesis), then the quantum act at the beginning of the universe merely converted energy into different forms, that is, the net energy of the universe is still zero, and the law of conservation of energy is upheld.
Is this necessarily the case? No. As with all matters of current physics, things are still undergoing experimentation (please see the research of Vilenkin, Linde, Guth). Many physicists have a flurry of ideas as to what could constitute the "beginning" of the universe, but all of them far from involve the invoking of any sort of omnipotent being. The point I simply wish to make is this: we know of several ways the universe could have come about naturally that are wholly in accordance with the laws of physics. There are natural alternatives to this act of "Genesis" of the universe.
And when there are natural, plausible, alternatives, that are currently being tested in laboratories and continue to develop, they are always more reasonable than explanations invoking the supernatural. If I lose my wallet, it could definitely be true (and I'd have no way of disproving it) that elves jumped into my pocket and stole it, but the more reasonable answer is indeed the natural one, that I simply misplaced it, or even that quantum tunneling occurred and it's in the next room over. To believe the universe came to it's current state by the act of a supernatural force is an intellectual copout and the equivalent of believing elves took my wallet. Never has a supernatural effect been observed in any sort of scientific lab setting, and it definitely does not require "faith" to believe that something does NOT violate all the existent laws of the universe.
Allow me to close with a quote Professor Alan Guth:
"It's not a coincidence that the Bible starts with Genesis. Most people really want to know where we came from and where everything around us came from. I like to strongly push the scientific answer. We have evidence. We no longer have to rely on stories we were told when we were young."
Nam et ipsa scientia potestas est.
Explaining the universe by invoking god is like solving an equation by multiplying both sides with infinity. It gives you a trivial solution and wipes away any real information about the original problem.