FEBRUARY 24th, 2016
By LANA CARBON
Being a comic book nerd my entire life, I have long been interested in the subjects of time traveling and multiple dimensions. Ever since the iconic DC comics story of Crisis on Infinite Earths and Marvel’s entire What If…? line of comics, I have wondered about what lies beyond what we know of our lives as we are living them currently. The new show DC’s Legends of Tomorrow takes us through a temporal adventure which feeds my curiosity of timelines and the effect little changes can make.
I’m sure I’m not the only one. Who else hasn’t wanted to see their future, meet someone from the distant past or wondered what would have happened had you only made a different decision at some point in your life? I have been reading quite a few interesting articles lately about the topic and this started making me think deeply about the concept; when I began discussing it with John, we thought it would make an interesting blog post.
Now please keep in mind that we are in no means scientists and don’t claim to fully understand the processes of quantum physics, string theory or science in general. As such, we would greatly appreciate comments, corrections and clarifications to any topics we include in our thoughts here. Our only request is to keep any comments understandable to us non-scientific types.
Time Travel - Is It Possible?
Putting aside the fact that we are constantly traveling into the future at the rate of an amazing one hour every hour (boring) or that we can technically see into the past every night while we are looking at the stars (e.g. the light we see from the North Star today originally shone 323 years ago), will it ever be possible to physically make jumps through time? This topic has been studied by the greatest minds of all time including Albert Einstein and Stephen Hawking.
I don’t pretend to understand the effects that gravity and speed have on altering the rate in which time passes but according to my limited readings, it has something to do with Einstein’s Theory of General Relativity (that has recently hit the world wide news again with the gravitational waves from the collision of two black holes of which we now have physical evidence). What I did pick up from reading about this is that the closer to the speed of light we achieve, the slower time passes. The same can be said for proximity to sources of massive gravitational pull…like black holes. The downfalls here are that the faster something travels, the more mass it gains and the more energy necessary to maintain its speed (maintaining light speed would take the equivalence of half a galaxy’s energy) and the singularity of a black hole would merely crush us in its gravitational pull. Don’t lose hope yet though…enter Kerr Rings and the Einstein-Rosen Bridge (better known as wormholes). While both are theoretically possible, they are highly unstable and even if we could travel through them, the portal may close and never re-open1.While being stranded in time makes for a great story, I would argue that the reality of it would be nowhere nearly as entertaining.
The Problems with Traveling to the Past
One theory that stands out to me is from Stephen Hawking, who does believe in the existence of wormholes and the ability to travel through time to the future… but not into the past.
“This kind of time machine would violate a fundamental rule that governs the entire universe - that causes happen before effects, and never the other way around. I believe things can’t make themselves impossible. If they could then there’d be nothing to stop the whole universe from descending into chaos. So I think something will always happen that prevents the paradox.”
"In the end, I think a wormhole like this one can’t exist. And the reason for that is feedback. If you’ve ever been to a rock gig, you’ll probably recognise this screeching noise. It’s feedback. What causes it is simple. Sound enters the microphone. It’s transmitted along the wires, made louder by the amplifier, and comes out at the speakers. But if too much of the sound from the speakers goes back into the mic it goes around and around in a loop getting louder each time. If no one stops it, feedback can destroy the sound system.”
“The same thing will happen with a wormhole, only with radiation instead of sound. As soon as the wormhole expands, natural radiation will enter it, and end up in a loop. The feedback will become so strong it destroys the wormhole. So although tiny wormholes do exist, and it may be possible to inflate one someday, it won’t last long enough to be of use as a time machine.”
“Any kind of time travel to the past through wormholes or any other method is probably impossible, otherwise paradoxes would occur. So sadly, it looks like time travel to the past is never going to happen. A disappointment for dinosaur hunters and a relief for historians"
- Quotes by Stephen Hawking2
If this is indeed the case and travel to the future is possible, would we ever be able to verify the truth? Considering it would be a one-way trip because once in the future, it would become the present and the present would then be the past and if we can’t travel to the past, we couldn’t return to the present to let people know we went to the future.
I think I just confused myself.
…That being said, let’s forget about traveling forward in time for now.
Potential Outcomes of Successful Time Travel to the Past
Let’s put aside the ‘how’ for the time being (no pun intended) and assume that time travel is possible. What would the ramifications be of messing with the space-time continuum? This is where we pull off impressive terms like the Law of Causality. This is also known as Albert Einstein’s Theory of Cause and Effect. What if we were to create a scenario and imagine what might happen? The most obvious result of time travel is causing a time paradox.
One example of such a theory is known as the Hitler Paradox. By going back in time and killing Hitler before he could commit all of his atrocious acts, you would be erasing these deeds from history and hence the entire reason in which you traveled back to stop him in the first place. Therefore Hitler still continues on his familiar path because you didn’t go back to kill him. A secondary theory exists in relation to this one where the assassination is successful but the resulting changes actually make things worse (i.e. a more ruthless leader takes over and, through different choices, wins the war or without anyone invading, Stalin goes on the offensive and is the reason for World War II, etc.)
A more personal way to see the potential impact revolves around the time travel itself being somehow responsible for the death of one of your ancestors. While this is known as the Grandfather Paradox, I have changed it up just slightly to keep it original. For our purposes here let us use the example of accidentally hitting your grandmother with a car when she was still just a child.
Scenario 1 - Inconsistent Causal Loop (Similar to the Hitler Paradox)
With the woman who was to be your grandmother, dying before ever giving birth to your parent (the cause), her child (your parent) would never exist to give birth to you (the effect); meaning you would not have existed to travel back in time to hit this particular child (your grandmother) with a car. Events would occur as they always had.
Scenario 2 - Consistent Causal Loop AKA The Bootstrap Paradox
Before traveling back in time, your grandmother tells you the story of how she was nearly killed when she was hit by a car as a child. When you do make your temporal journey, you hit a girl with your car but the collision is only minor because you have your grandmother’s story fresh in your mind and are driving more slowly than usual. Your grandmother lives through the accident to not only become your ancestor but also to warn you time and again to slow down, therefore saving her life.
Scenario 3 - Post Selected Model AKA The Predestination Paradox
In this theory, potentially paradoxical events are avoided through probability fluctuations. What does this mean? Through highly unlikely circumstances, your grandmother would never be hit by the car. How this comes about could be nearly anything. Perhaps your car ran out of gas, or was hit by another vehicle, or even something less fantastical like someone calling her name causing her to turn back before the fatal moment. This theory leads into thoughts of predestined lives.
Scenario 4 - Parallel Universes
This time, when the girl is hit by the car, the timeline simply continues on from this point creating a completely divergent universe where a "you” will never exist. However, the person who ran over this child (you) were born in an alternate reality and hence carry on to live out your life. The rest of the world will maintain a similar (or parallel) course with only minor differences. However, if your grandmother or any of her descendants were famous, a world leader or important person in your own timeline, the changes in this new timeline could be quite substantial.
If anyone ever does figure out the science behind traveling through time, these paradoxes make me wonder if it would even be worth the trip. The majority of these scenarios lead to absolutely nothing happening any differently than it has already occurred. The last possibility that I mentioned would indeed change your own personal history but not that for any of your family and friends from your original timeline. At least this option provides a hint of hope while producing many more questions that would require equally elusive answers.
I must say, on a personal note, the last potential scenario of traveling into the past is my favourite theory. I like the idea of multiple versions of us all running around, living out our dreams. Of course, that probably means other versions of us might be exactly like us and then a few may even live in a nightmare world. The possibilities are seemingly endless. I do believe in multiple dimensions and wonder if time travelers are the ones responsible for them. Who knows…I like to imagine that maybe, just maybe, in some fantastic world out there we might even be super heroes.
For an Interesting Read