The more I learn about science and how the world works the more I come to understand why such a large percentage of the scientific community is atheist. Though I am fairly certain that no deities exist, my position remains one of agnostic atheism in that I don’t think it can be proven that no gods exist (even if I don’t think one does). This was not a trivial decision. When deciding if I should believe in a god I first pulled back to examine whether a god could exist, what it would have to be like, and what the chances are that such a being exists despite the lack of evidence.
Disproving the Christian god is easy as long as he is clearly defined with required attributes. In the fundamentalist Christian view the bible is to be taken literally, so disproving the god they believe in is as simple as demonstrating that the events depicted in the bible never took place. For me, the absurdity of many of those stories hardly merits investigation, especially considering how thoroughly they have been debunked already. But many theists don’t believe in this version of God. To them, God is a creator of the universe, and the bible is either metaphorical or even simply myth and came about independent of their deity. This idea of God is far more interesting to me because, unlike the God of the bible, this deist god isn’t so easy to disprove. It isn’t necessarily anthropomorphic and can take any attribute necessary in order to evade detection and still be a deity. For the sake of my discussion here I’ll assume this god is also the creator of the universe (though he doesn’t necessarily have to be, for my purposes here I am ignoring non-creator type deities, which is a different topic entirely)
Warning: Science content ahead!
To understand what this god must be like and what world he(?) exists in it is first necessary to understand the reality we live in. Specifically, space and time.
When we gained the ability to gaze into the heavens with a telescope, we learned that space is big. When we put Hubble in orbit, we learned just how much we underestimated how big the universe really is.
The image above is NASA’s Ultra Deep Field. Pictures like these are extremely humbling and really put our existence in perspective. The farthest galaxies we can see are 45 billion light years away, and it took the light that left them an entire 13 billion years to reach us. That means the light left those farthest galaxies 13 billion years ago and it happened to land right on our detector when we were looking. But those galaxies are not at the edge of the universe. Our universe is much more vast than that. In fact we really don’t know how big it is.
You probably know that a light year is the distance light travels in one year. So how could we see a galaxy that is 45 billion light years away if the universe is only 14 billion years old? This is why I feel that the Big Bang is rather confusingly named, because most people hear that and assume it was an explosion. It wasn’t. A better name might be the Big Expansion. The universe began to expand in all directions, not unlike blowing up a balloon. If you were to cover the balloon in dots and stand anywhere on the surface of the balloon as it is being blown up you would see all the dots moving away from you no matter where you stood. When we look up into the sky we see essentially this same thing except in three dimensions, almost all galaxies are moving away from us.
When I first learned this I found it rather confusing, because it seems to conflict Einsteins claim that nothing can travel faster than the speed of light. Before we explore that, we must understand why the speed of light is a limit to begin with. The answer is that we are already moving at the speed of light. Always. Just not in the way we think we are.
We are used to thinking of the world in 3D space. Only, there are more dimensions than that, at least six that we interact in. The first three are height, width and depth. The next three are collectively referred to as time. The way we move through time isn’t as intuitive as the first three dimensions since we experience it linearly, as though it was a single dimension and we are only aware of our present point. Reality is, we are traveling constantly at the speed of light through the six dimensions at constant velocity. If we speed up in one dimension we slow down in another to maintain constant equilibrium.
To use an analogy, imagine you are in a car with cruise control. The car is traveling at 50 mph. You cannot speed up or slow down. You can only control the steering, turning the wheel in either direction. If we were to plot out the ground you are driving on in a grid and started you at position (0,0) and you started driving in the x direction toward (10,0) at 1 grid unit per hour, then you turned toward the Y direction you would start moving slower toward the x=10 position. This is essentially how everything moves. If you speed up your movement in one dimension, it must slow down in the others because your true velocity does not change. Mass plays into this too, the more mass you have the more energy it takes to move in the three spatial dimensions. But in the case of light, where there is no mass to speak of, it travels at full speed in the spatial dimensions while sitting still in the time dimensions.
As a thought experiment, imagine you put a clock on a photon and it left one of those galaxies. 13 billion years later your clock reaches a telescope. How long does the clock say the journey took? The clock would show that no seconds had passed. From the clock’s perspective, it arrived at the same moment it left, as though your destination was right next to your point of departure. In fact, you don’t need to be moving at the speed of light to see the effect of time slowing down on something that is moving faster than something else. Our GPS satellites work by sending the time on their clocks down to earth via signal. Our GPS device reads the signal from three or more satellites and compares how far off they are, and which satellites it is receiving from, to determine your position. The idea is that the signal travels at the same speed from each satellite, so the signal that arrives second is from a satellite that’s further away, and it can use the time on the clocks to compare them. But the satellites are in orbit, and therefore moving much faster than a clock on the ground. Because of this they must be checked and usually updated every few minutes to make sure they didn’t drift.
If you could board a hypothetical train that travels at 99.9999% the speed of light, then while underway you stand up and start walking toward the front of the train, what would stop you from traveling faster than the speed of light? The answer is time. Since you’re moving so fast in the spatial dimensions, you are moving very very slowly in the time dimension. So someone watching the train whiz by would see everyone inside frozen but for you time would feel like it’s moving normally as you walk toward the front of the train.
Since nothing with any mass can travel faster than the speed of light, and we now understand why, how are galaxies 45 light years away in a universe that is 14 billion years old? The answer goes back to the expansion of space itself. Space is expanding at a very rapid rate, and the universe is expanding as a result far more quickly than the speed of light. In fact, the reason we can’t see anything beyond the 45 light year limit isn’t because there are no galaxies there, but because space is expanding faster than light could travel at that distance. Light leaving a galaxy further away would travel toward us forever but we are moving further away faster than the light can go. This is also why distant galaxies appear so young. Light left them 13 billion years ago and traveled toward us against the expansion of space before finally arriving on our telescope.
So it would be more accurate to state that nothing can travel faster than the speed of light except space itself.
As a side note, the OPERA experiment showed results that suggested that neutrinos traveled faster than light. The scientists knew this was not possible according to our understanding of relativity, so they sought help finding what was wrong. The problem turned out to be an improperly connected cable. Still, had they made an actual discovery it would have been exciting, because breaking the rule on the speed of light is a holy grail among physicists. Given the above information it’s probably obvious that this may not be possible.
At this point the obvious thing to do is take this back to the moment of the Big Bang. Conventional wisdom is that there is no time before this event. In fact, with our current understanding of time as three dimensions not unlike spatial dimensions, the idea of going back to the “beginning” of time is somewhat meaningless as there was no beginning as far as spatial time is concerned. If you walked to the south pole and kept walking you would simply pass it without realizing, and time is no different.
If time is just another set of spatial dimensions, why can’t we travel through time by simply reversing course? (note that I am oversimplifying this a bit) It is possible to change direction in this dimension since gravity can influence it—this is why mass affects this—but to have a significant impact you need a mass that is gigantic. Like, a black hole. Seriously, black holes could be used for time travel if they didn’t rip you apart first, but you could only go back to the point the black hole was formed.
Assuming that could be overcome, one analogy that could be used to describe how difficult this would be and how much energy would be required would be to imagine a giant asteroid plummeting through space at 50,000 miles per hour. How hard would it be to stop it and change directions? What are you going to push against? Now imagine trying to do that with something traveling at nearly the speed of light and in a dimension that is very difficult to manipulate. This is why we can’t build a time machine, at least not with our current level of technology.
Scenario 1: God exists outside of space and time
Before the Big Bang space and time did not exist yet, so there was no room for movement to occur. The entire universe was tiny, and traveling in any direction would mean moving in a loop. Imagine having a short hallway with a portal (from the game Portal) on both ends of the hallway. You could run in either direction but would continue moving in a loop. Now imagine that this hallway is microscopic. That’s what the universe was like.
For a god to exist outside of space and time like this, they would be unable to experience either. In other words, if they triggered the big bang, the entire life of the universe would pass in an instant from their perspective. Not only would this god be indifferent to our existence, he would by necessity be unaware. If we assume that this god can use indirect observation, then even then he would only be observing us long after the fact. (and, again, the indirect observation ignores the fact that this being couldn’t interact with time)
Scenario 1.5: God interacts in “higher” dimensions
One common argument I’ve seen is that there are more than the six dimensions we interact in, and only the first six are dependent on space itself. The idea is that God can interact in both. While more dimensions do exist, and more may exist that we are not aware of, all those that we know about are dependent on each other and all exist within space/time as we know it. For dimensions to exist that are independent of these, we would basically just be describing Scenario 1 again.
If you are in a space ship traveling at ½ the speed of light and a beam of light passes you by, will it whiz by at half the speed of light relative to you? Surprisingly, no, it won’t. It will still appear to be going the full speed of light. The reason why is because light is traveling entirely in the spatial dimensions, while you are still traveling through space and time. Light will still pass you as though you were sitting still because you are both essentially traveling in different directions. So it’s not like passing on parallel lanes on a freeway, it’s more like passing perpendicular on an overpass. The car passing on the perpendicular highway will still appear to be going full speed.
Scenario 2: The Big Bang was not the beginning
I’ve actually seen Richard Dawkins point to this as the one scenario he could imagine a possible god existing in the film Expelled. For space and time to have existed before the Big Bang, there would have to be another earlier Big Bang event and ours happened inside existing space and time. As Dawkins pointed out, this “god” creature (or entity) would have had its origins in the previous universe and would have come about by natural means. While he pointed this out only to humor the interviewer—I agree with him that the idea is rather far fetched—it is at least within the realm of possibility. Most physicists nowadays think there was something before the Big Bang, we just don’t know what.
For this scenario to be true then we would need to find evidence of an earlier big bang. The best evidence to look for would be a galaxy (or galaxies) that are clearly the wrong age. Remember that galaxies get younger the further they are away because of the time it took for light to reach us. If we find a really old one that’s far away then there is our evidence. I don’t expect to find that, however, because the older universe would be expanding right along with our younger one, meaning that older galaxies are likely too far for us to see. The expansion of the universe would outpace the speed that the light is traveling toward us. But we can look for a younger big bang event. If we find one, we could infer that an older one was possible and even likely.
So even though this scenario is possible it has a few holes of its own. First, it still requires that Big Bang events can and do happen naturally. They would have to for God to get there, after all. Second, assuming ours was triggered by some intelligent being, he would still be unaware of our existence and quite likely is long dead.
Scenario 2.5: God did not create the universe, but did create life
This is the first scenario where God could even be aware we exist, but even then he may not know humans evolved. Even so, this is still just a variation of Scenario 2. Life had to start naturally somewhere. All this does is moves the abiogenesis event elsewhere.
Imagine that you are God in this scenario. You return to the planet that you started life on after a few billion years and find that humans have evolved. A sentient race capable of building cars, sky scrapers, and landing on the moon. Would you demand worship? Would you be worthy of worship if you did?
It is very possible that humans could one day plant life on any habitable world that is devoid of it. If this happens, it seems very unlikely to me that we would start life then abandon the planet. More likely we would start a biosphere for ourselves to live in.
Scenario 3: Magic
Often theists have a really hard time imagining life coming about on its own, so they reject the above ideas and assume that God always existed and magic’d us into being. The problem with this scenario is that it rejects all the evidence that we are seeing. I’ve often seen this scenario referred to as the Loki scenario. Loki was the Norse god of mischief. The idea is that God planted the evidence just to mess with us. If this is the case then God was not only malicious but strikingly thorough.
Scenario 3.5: Reality is different from what it seems
There was a hypothesis proposed that our entire reality exists inside a computer simulation. The idea is that the being we could call God is simply the technician that operates the computer in which we live. Our entire lives are essentially a video game.
The first and most obvious problem with this is the sheer amount of computing power this would require. Think about how big the universe is. Or better yet, just think about how powerful a computer you would need to simulate every person, animal, plant, and computer just here on earth. I could write an entire article on the improbability of this scenario, and such articles have been written, but it can’t be 100% disproven. Still, the whole idea seems incredibly illogical when you consider how much they’re simulating. Since there is no evidence for interaction with the creator of the simulation which would suggest that it was created for entertainment purposes, the only other logical reason I can think of for them to do this is to simulate their own universe for scientific study. This means they wouldn’t interfere with their experiment, which brings us back to square one.
Given the above, the chances that a god of any kind exists is quite an extraordinary claim, especially given the lack of evidence. Until some evidence does turn up I would say the odds are negligible, and even if a god does exist, none of these scenarios suggest that there is an afterlife.