Monday, December 12, 2011

Gravity follow up Question

I received a really great question concerning gravity after my previous article about Space-time, Quantum Mechanics, and the Cosmological argument for God.


The question was raised:


In addressing "why there is something rather than nothing" your article states:
"Likewise, the related question of why there is something rather than nothing (within the universe) can also be explained. The answer is gravity. Entropy x gravity = clumping. This clumping of matter is what creates stars and planets. Gravity, in other words, is why we have something rather than nothing in the universe."


Honest questions here:
*Why is there something available to be clumped? You say gravity is the reason for there being something rather than nothing, but if there was nothing for gravity to act upon, there would still be nothing.
*And isn't gravity a function of mass (mass of a something)?

Maybe you just shorthanded your treatment of this question. What am I missing in understanding this?


I don't think you're missing anything. As you correctly state, gravity is a function of mass, but let's not forget a function of energy also. 

Why is there something available to be clumped? Because of the big bang. At least that's how I have come to understand it from reading physics books. All the energy in the universe (as far as I can tell) spontaneously popped into existence via the quantum fluctuation, or singularity. Next, as the MIT physicist Alan Guth has posited, inflation takes over and this hot dense plasma is spread out across a great distance via inflation. Gravity then begins to collect the gas clouds of mainly helium and hydrogen and eventually the mass of this gas gets so dense that it ignites a nuclear reaction from the sheer pressure of the mass being compressed. This chain reaction creates a stellar furnace of super giant primordial stars.

Eventually, as any astrophysicist would tell you, these super stars go super nova and explode and create new elements baked in their fiery furnaces. All the natural elements we have identified thus far are known to come from stars. Every piece of matter that exists today was baked up in a star then distributed back out into space in that stars subsequent death. 

Gravity, meanwhile, continues to clump the stuff of stars together along with the other gases and dust swirling about. Soon after, gravity forms nebulae. Eventually the right type of star goes super nova and collapses in on itself forming a black hole. With enough nearby gas, dust, and debris a galaxy can form. Like our own Milky Way galaxy, eventually planetary systems are formed, and all of this spins around the massive black hole at the center.


Meanwhile, the with the recent discovery of dark energy, physicists have a good idea of what is driving the universe to expand exponentially. 

At least, this is how I understand the evolution of our universe to be like from reading physics books. However, I am by no means an authority on the subject.

My point about gravity being the answer to why there is something rather than nothing is this. If there was no gravity, then there would be nothing acted upon. No effect in other words on the stuff after the big bang. Basically the hot plasma after expansion, minus gravity, would never clump and dark energy would continue to force all that energy apart while entropy would erase it from existence. Nothing would ever come to be. 


This causes me to feel that theologians are asking the wrong question about the origin of something with regard to nothing. Because even with all the energy left over from the big bang, without gravity, we would still have nothing. We wouldn't even exist to ask the question. 

So the answer of why there is something rather than nothing is quite clearly: because gravity.

The answer of where did this something come from is: the big bang.


How did stuff form after the big bang? Physicists suppose it has something to do with Symmetry breaking.

The answer of what caused the big bang is currently unknown. Or, perhaps I should say, not fully understood. 


Most physicists think it was likely a quantum fluctuation (of some kind). Yet the field of quantum mechanics is fairly young and it is not completely understood either. Luckily this is why various branches of cosmology and physics exist--so we can continue to investigate the unknown elements of our universe perchance discover why it is the way it is and how it came to be. 

I feel that I must now point out that although we don't currently understand everything about the nature of reality, scientists are making steady progress at increasing our understanding of the over all picture of reality. 


Gradually they are pulling the curtain which veils reality and hides her from us further and further back revealing hitherto unforeseen truths. With each new discovery our understanding of the overall picture of reality grows ever more complete. 


Although I can only speak for myself, it seems to me that if religion were true, according to the claims religion makes for itself, then it would be the vehicle to revealing all the truths of reality. Since this is not the case, it makes me highly skeptical of anything religion has to say with regard to reality--the world--the universe--or myself.

Now, it stems to reason, that if you assume something "caused" the big bang--although this assumption is illogical knowing that causation cannot exist outside of temporal space-time--even if we wish to ignore the erroneous nature of the question and simply rephrase it--the question would probably have to push back to where did that initial energy fluctuation come from? 

That is still a question currently undergoing investigation. Physicists are currently working on figuring that out--from many different angles--so it is too early to tell with any certainty. 


Which brings me to the second part.

Many physicists, including Stephen Hawking and Michio Kaku, posit that gravity exists multidemensionally. At least, the math seems to suggest it (as I am not a physicist I am inclined to take their word for it--esteemed as they are).


If so, then gravity would exist whether or not our particular universe did.


As I hopefully showed in the article, the logic behind the Cosmological argument is Newtonian. But modern physics and cosmology goes far above and beyond that type of reasoning. Especially where gravity is concerned. 


Modern cosmology suggests that there is a minute vacuum energy to the quantum foam of space. This vacuum energy has recently been tested by Swedish physicists who used a virtual mirror to push a virtual particle out of the vacuum energy and it immediately formed into a tangible light particle. That is amazing. They literally tapped on vacuum energy, the closest thing to nothing there is, with a oscillating magnetic field and got a light photon out of it. 

Basically they made light from nothing. That's just cool. Although it doesn't provide ready answers--it is a step in the right direction. Slowly, but surely, we are piecing together the puzzle of how the cosmos came to be.

I think I should mention that gravity is also mysterious. It may even be multi-demensional (according to several physics theories). We have only been able to measure it indirectly. But new instruments are being developed which will have the required sensitivity to measure gravitational radiation in the near future (see the Michio Kaku video below). As I understand it, its frequency will tell us a lot about the nature of gravity and how the universe functions/behaves. So I am eagerly anticipating that discovery.


It seems to me, and this gets back to my initial point, if there really were a theistic deity of a power and magnitude such as the type which theologians claim, then this power has to interact with reality (otherwise what good is such a power if it remains forever unknown? It might as well not even exist--if that's the case). If there is a God, such as the one theists posit, it can be assumed that it interacts with the universe and so should also have observable effects. The fact that we don't see any, would, it seems to me, suggest there is no such being.


Advocatus Atheist

Advocatus Atheist