The Philosophy of Time Travel

Is this about to be a forum for all manner of Heinlein discussion?

News Flash nerds – this one has already been solved. The latest episode of South Park shows how Cartman, who gets himself stuck in the future because of a botched scheme to freeze himself, is able to alter the past by using a future toy phone that allows one to crank call the past. It’s really that simple. So, if somethinng goes wrong for you in life write in your will for one of your kids to crank call you from the future and tell you not to make that mistake. How hard is that to figure out? Not at all. So much for a bunch of stupid philosophisizers and their "Time Suicide Paradox." Whatever.

Doing a fair bit of time travelling in my fiction, and I avoid all of the nasty paradoxes (paradi?) with the simple assumption that travelling backward in time is possible, but by doing so one ends up in a separate time line. You never alter your past, but you can alter the past of someone who thinks they are you (although this becomes a precondition of their timeline, and is therefore not an alteration.)

Does time travel violate Conservation of Energy?

I ask for this not to be analyzed using Einstein’s approach. Rather, will physics take the approach that time is "mostly" linear? Such that if an object were to travel through time, it’s energy/mass ceases to exist in time frame N and is added to the sum energy/mass of time frame N+10years or N-10years.

Or … as conservation of energy applies to closed systems, perhaps the scope of the system should be questioned. Would time travel encompass the dimension of time as well, such that no violations have taken place?

Now, perhaps I’m applying the wrong parallel here. Would this at all be similar to Schrödinger’s Cat? The existence of that object is something of a superposition, unknown without direct observation as it moves through time. Perhaps even moving through time such that TWO of them exist in the same time reference – could that not be equal to the superposition observed at the subatomic level?

Let’s assume you decide to travel into the future. If there was such a thing as free will, it should be impossible to have any discernable destination. For instance, you decide to travel forward in time to meet your great-great-grandchildren. In order for them to exist in a future that you can travel to, a necessary timeline would have to take place whereupon certain individuals met and had children, etc. etc. This would imply fate as key events must take place for the voyage to occur. Without fate it would be impossible to have any destination as an infinite number of potential outcomes are possible.

Now, if free will does exist and you are able to travel into the future, there is no guarantee that two individuals traveling to the future would necessarily land in the "same future." This follows the multiple world concept (somewhat akin to the movie "The One" starring Jet Li).

Traveling into the past would seem "logically cleaner" as events have already transpired and you should be able to jump into them. However, the Observer Effect will inevitably alter the outcome of time as it would be impossible to be present in the past without having some influence.

Unless, the world were governed by fate. In that case, you could travel back in time because you were "supposed to" and the past has already compensated for you being there. While you may perceive that you are altering things, the circular loop of time that you are involved in will show that event has always taken place and fate requires that you DO travel back in time to do it. This would allow you to actually return to your own time reference without having created any anomalies, because it has always happened that way.

Free will, throws a monkey wrench into the system because conceivably you could alter the past in such a way as to negate the fact that you ever existed. Or alter the past such that time travel was never discovered which means you never went to the past which means you could never have disrupted things. BLAAAAAAHHHH (runs away with hair on fire waving arms in the air). Or, avoiding the self-negating paradox, free will causes the same problem as traveling into the future – how do you return to your "present" if your existence in the past introduces variables and options that will inevitably create numerous pathways through time?

Thus, it seems to me, that for time travel to exist – it is a requirement that 1) FATE exists and man has no FREE WILL or 2) somehow the multiple world/dimension thing exists and we simply move through those worlds based on choices (which isn’t that far from actually being fate anyway).

Now … ummmm … if my other requirement for time travel (that fate is necessary) is true. What would that mean for religion?

• time travel is impossible because it will violate religious principles
• time travel refutes religion
• religion is MORE real because God’s will creates a pathway of fate

Perhaps man is fated to endure a cycle of genesis and revelation over and over and over again. This would actually create very compelling evidence for religion – although it would fly in the face of contemporary perceptions of free will.

this post is less involved in the ‘free will – fate’ part of the above article, but more on the idea of time travel and the effects thereof.

travelling to the past is theoretically rather easy, as you can see where you will be going. any foray into the past will have no effect on the ‘future’ (or percieved present), as anything you do will, from your perspective, already have happened. this means, while it is impossible to change an event in any way, you may act as you damn well please, as it won’t have the slightest difference.

travelling to the future is somewhat more difficult. the future as we see it from the present is indeterminate – we don’t know what it will be like. unfortunately the simple act of observing any particular future will have the efect of making it the true future. travelling back from this future will have the same effect as travelling into the past from the present – the latest (most progressed) point in time will be determined and unchangeable: your actions to make it happen differently will have no effect at all.

that’s the time travel bit out of the way, now for what it means. a lot of people get worried about this sort of thing, as it seems to eradicate free will. however, my above description (if it is correct) shows that while each individual has free will, once you bring time travel into the the picture, whether back or forwards then back again, it doesn’t mean squat. the unchanging ‘future’ does seem to imply fate, howeveronly in the big picture. yes, nothing you do can change it, seeming to indicate fate for the whole human race, but what you do is completely up to you.

perhaps what this means is that each of us is fated somehow, at present indeterminately, until someone goes into the future to find out what happens to us. when (read ‘if’ if it makes you more comfortable) this happens, our ‘fate’ will be determined, however everything we do up until then will be a product of our own free will.

I don’t know how it happened but I and my husband both saw a ‘solid’ ghost in our bedroom in the early morning hours 3 years ago. She was tucking me in bed, literally moving the covers around me. My husband felt her tapping the bed, woke up, saw her, (I saw her standing at the end of our bed and around our bedroom that night)and said, ‘what or WHO is that?’ to me. I said ‘I don’t know…’
well, long story short, she immediately moved across the room and vaporized into thin air.
We didn’t know who she was… for several years, until we returned to another state to bury my father. I told one of my brothers about it (we were talking about life after death and wondering if my father was okay) and we told him what she looked like: older style clothes, gloves, tiny waist, hair parted in the middle, short, serious, little black hat with round brim, a veil, gloves…. he said: ‘I know who that is! Have you ever seen a photo of our great grandmother when she was young?’ He showed us an old photo and it was HER!!! (without the hat…)

Anyway, I’m sane, my husband’s sane. We BOTH saw her. We both will never forget it!

I never saw her again, nor did my husband. BUT we both know that time travel must exist … or else how could she travel from that time to this… she was solid… she had piercing eyes… I know what I saw; my husband is a scientist; I’m a writer.

This blows our concept of ‘reality’ away: time is flexible; people are immortal; people can materialize and dematerialize; what is reality anyway… isn’t it a concept? Is reality really real?

I’m going to borrown heavily on this article for information. But John Cramer, a physicist as the University of Washington is going to push an experiment in quantum physics to test a paradox called "entanglement; also known as the Einstein-Podolsky-Rosen paradox.

If I’m reading this right (wyldling, please jump in with your physics guru-ness), engtangled photons will impact one another irregardless of their separation in time or space. "It’s all incredibly counterintuitive," Cramer acknowledged.

These physicists are going to use a detector to demonstrate the entangled properties of photons and how they affect one another. (This blog post has some good graphic depictions of how such an experiment takes place). Then, one of the photons will be sent through a long, fiber optic loop designed to delay one of the photons by 50 microseconds. In theory, if the first photon still demonstrates the entanglement upon detection, that will mean it was influenced by the other via retrocausality.

This will likely torture the Matrix’s Merovingian to come up with a replacement for his cause and effect speeches.

I am going to warn anyone who reads this, especially I they have any kind of a physics degree whatsoever, that what follows is purely out of my imagination, and so will require major debunking by anyone who cares to. (I almost hesitated to post it, but what’s a lowly level 5 Par-Nerdum got to lose anyway?)

I have seen several statements in previous posts that read something to the effect of “objects moving through time”. This sets me to thinking what a thing has to be in order for something to move through it. I have heard time be called ‘the fourth dimension’, and that seems to jive with the ‘moving through it’ statement, because if something is dimensional in nature, then you can move along its coordinates, even if it’s only a single line. But then I began to imagine that this is where the analogy has gone wrong. Some of the posts between VNutZ79 and wyldeling (who IS the answer grape btw!), and myself sort of got me thinking about matter and energy and how it relates to time. My thoughts start with a question. Does time exist in a perfect vacuum? And I mean vacuum, no particles, matter, energy or waves; magnetic or otherwise. Maybe time is the byproduct of the interaction between matter, energy and its movement through space. This might render it an untravelable (yet measurable) entity and not a dimension at all. I suppose there is no way to physically prove if time exists in a vacuum anyway.

If you were able to hang on to a light beam and travel at its speed, the formulas say that time would stop for you. If you and your light beam were slowed down by matter, magnetic waves, etc, does time begin to creep forward slightly for you because of this slowdown? Does this movement of time come from the reaction between the light and whatever force was slowing it down?

It’s now time for bed. Goodnight.

Have you also read the article about Modelling time travel in fiction at http://qntm.org/models? It discusses the same schools of thought at greater length. There again, have you read ‘The Time Traveller’s Wife’ by Andrea Niffenegger – now there’s an original concept! At least, it was to me.

My issue with the concept of time travel is viewing time as a medium in which one can travel backwards. I conceive of time as more of a relative measurement of things that move. I can see time stopping if all motion stopped, I can see time flowing at different rates due to approaching light speed, but I just can’t see travelling back in time. To me, travel back in time would imply rolling back all of the motion from now to then. All of the worries about time travel paradox I think are purely imaginary. Accidentally killing your parents could only result from making the universe go in the opposite direction.

I’m going to hypothesize out of my butt for awhile, since I have been too far removed from academia to know anymore which theories I’m blaspheming or alluding to.

Indeed, the Doppler Effect. However, I was thinking of something slightly different. (MARK! Why haven’t you coded a whiteboard into this site? Gosh, you’re so useless) This would be easier if I could draw something, so let me try describing it. Let’s view an object from the side, traveling from right to left with an observer on the left.

Traditionally, you would think of the doppler effect because the light is traveling exactly in line with the object. But imagine you are looking at the "dented plane" from the side. If there were no objects denting it, it’s like looking at the edge of a papersheet – or Kate Moss sideways. Drop an object (of ridiculously large mass, just shy of being a singularity) into it and it bends down in the "traditional" sense. Now, if that object began moving to the left at relativistic speeds and the gravity well lags it like a wake, then there should be an angled funnel. Would it be possible that light (or generic radiation) becomes so channeled by the steepneess of the funnel that it can be seen from only one direction?

I think I may have answered my own question in my mind (just now). That model describes a single plane … whereas in reality, there are an infinite number of planes depending on which way the radiation is traveling. But still, if the radiation is traveling along that plane, then perhaps my skewed funnel example still applies. It could be possible, that light never from the obsever in front of the mass never reflects back. Rather, because the funnel is tipped backward, the light does not actually bend, reach the object, reflect and return to the observer. Rather, it moves towards the funnel opening, drops in, but skips off the back and continues moving forward.

Now, I moved this to the Philsophy of Time Travel threads because these aren’t these gravity wells part of the basis for wormholes?

If the mass were large enough to create a singularity type gravity well AND moving fast enough to drag the well’s opening … are there any hypothesis for the well "tearing off" and creating a gravity bubble, or freeing a mass from the influence of other gravitational fields until slowing down again?

Well, now that it’s in the open … my colleagues asked what I was laughing at to which I said, "ah, just an Internet joke," as I didn’t want to tell them I was laughing at retards.

One needs only to extinghuse a match between the index finger and thumb to know the existence of now. Then, when next appreciating a comfortable chair, relax, close your eyes. Remember your first kiss. Then without hesitation, think excitedly about a future event. Some time with a special someone this Friday; another kiss perchance. Maybe the golfing vacation next month.

You’ve just traveled back in time as well as forward in time. Effortlessly. Seemlessly. As far ahead as we want (what I’ll do retired)or as far back (that rotten school yard bully).

This IS time travel. And it is wonderous!