# Time Travel: Possible or Impossible? **URL:** \ **Category:** Great Debates\ **Created:** [January 7, 2009, 1:55am UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178 "2009-01-07T01:55:46Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 7, 2009, 4:30pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/21 "2009-01-07T16:30:41Z")
> [@Ethilrist](#): > > This. > > Mankind hasn’t been able to demonstrate itself as being sufficiently bright enough to pay attention to pretty much every time travel story ever written for people to invent the thing and not use it. Once invented, the ability should be available from that point forward, so, unless this particular time (aka our recorded history) is considered so fantastically dull that nobody wants to visit it, we should be up to our armpits in time travelers. Not necessarily. If you have a finite number of of future time travelers, as well as finite number of time/places in the past for them to visit, then the distribution of time travelers in their past (our “present”) will not be “up to the armpits”. While I can imagine time travel being possible. I really cant imagine it being something that every tom who’s dick is hairy from the future is spending all their time visiting every possible moment in the past. ---
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [January 7, 2009, 4:57pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/22 "2009-01-07T16:57:28Z")
If time travel (to the past) is possible, then human history would continually change, as time travellers changed things. also, causality is still one principle that must be observed-results CANNOT precede actions. If this isn’t true, then you can throw out 99% of physics. ergo, time travel (to the past0 is impossible. Or perhaps, time is a dimension that we cannot observe directly, and all possible actions occur along a continuum-perhaps that is God’s way of knowing everything. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [January 7, 2009, 5:00pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/23 "2009-01-07T17:00:13Z")
> [@billfish678](#): > > Not necessarily. > > If you have a finite number of of future time travelers, as well as finite number of time/places in the past for them to visit, then the distribution of time travelers in their past (our “present”) will not be “up to the armpits”. Well, if you had time travel to any point in the past you’d have ALL future people able to travel back. Not just the 6 or so billion we have today on earth but the 6 billion tomorrow and the day after that and so on. The possible number of travellers from the future = ALL future people till the end of time. While maybe not exactly infinite it is a staggeringly large number (assuming the human race continues to exist in some fashion for the next several billion years). ---
**Author:** ![Paleface](https://avatars.discourse-cdn.com/v4/letter/p/f19dbf/32.png) [@Paleface](https://boards.straightdope.com/u/Paleface)\ **Post date:** [January 7, 2009, 5:01pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/24 "2009-01-07T17:01:10Z")
Impossible. Why? Time doesn’t really exist. Time is nothing more than a unit of measure created by mankind, just as the “inch”. Neither minutes or inches exist. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [January 7, 2009, 5:05pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/25 "2009-01-07T17:05:46Z")
> [@ralph124c](#): > > If time travel (to the past) is possible, then human history would continually change, as time travellers changed things. also, causality is still one principle that must be observed-results CANNOT precede actions. If this isn’t true, then you can throw out 99% of physics. > ergo, time travel (to the past0 is impossible. If time travelers were going back in time and mucking with our history we’d never know it at all. Your history would be changed along with it and all would seem normal even if your whole past just changed 10 seconds ago. Maybe 10 seconds ago you did not exist, someone changed something and now you do. There is no way for us to know one way or another. As for physics I think when physicists look at their formulas about how the universe works they are time invariant. That is the calculations can be run backwards and forwards just fine. There are no unidirectional formulas in physics that only work one way but not the other. That is why, so far, physicists cannot flatly rule out time travel (at least I think that is the reason). ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [January 7, 2009, 5:08pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/26 "2009-01-07T17:08:56Z")
It should be noted you can sort of time travel today. If you move very fast time slows down for you. IIRC the cosmonauts on the Mir space station who stayed there for months were 3 seconds or so behind when they left upon returning. Nothing noticeable of course and they are not in our “past” but to them their return put them 3 seconds into the future. If you got on your spaceship and flew near light speed for awhile a few days may pass for you but upon return you’d find yourself in the future. Of course this only works one way but if you really want to see what the year 2500 looks like you could in theory do so in your lifetime…just travel really, really fast for awhile. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 7, 2009, 5:29pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/27 "2009-01-07T17:29:23Z")
> [@Whack-a-Mole](#): > > Well, if you had time travel to any point in the past you’d have ALL future people able to travel back. Not just the 6 or so billion we have today on earth but the 6 billion tomorrow and the day after that and so on. The possible number of travellers from the future = ALL future people till the end of time. While maybe not exactly infinite it is a staggeringly large number (assuming the human race continues to exist in some fashion for the next several billion years). IMO? NO You either need an infinite future AND a civilization that lasts that long, or an infinite number of time travelers where anybody can easily travel into the past…AND they pick here and now (roughly speaking) for us to be up our armpits in time travelers. The fact that we aren’t only tells me “something” isnt infinite and/or there are actual “gasp” practical considerations when it comes to time travel. Its sorta like the lunites proclaiming that moon-earth travel isnt possible because they aren’t up to their armpits in earthlings. ---
**Author:** ![Markxxx](https://avatars.discourse-cdn.com/v4/letter/m/5daacb/32.png) [@Markxxx](https://boards.straightdope.com/u/Markxxx)\ **Post date:** [January 7, 2009, 5:33pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/28 "2009-01-07T17:33:43Z")
> [@Bryan\_Ekers](#): > > The fact that we haven’t been inundated with future-tourists suggests to me that _if_ time travel is invented, it’s so far in the future that whatever species accomplishes it has no interest in us I agree with this with the possible exception that we are the FIRST generation. In otherwords no other Earth humans (or whatever) has gone before us. You have to distinguish between time travel strictly within the realm of Earth and time travel between planets, galaxies and such. There may be other civilizations somewhere in the universe but they may be so far we’d never know. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [January 7, 2009, 5:43pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/29 "2009-01-07T17:43:25Z")
> [@billfish678](#): > > IMO? > > NO > > You either need an infinite future AND a civilization that lasts that long, or an infinite number of time travelers where anybody can easily travel into the past…AND they pick here and now (roughly speaking) for us to be up our armpits in time travelers. > > The fact that we aren’t only tells me “something” isnt infinite and/or there are actual “gasp” practical considerations when it comes to time travel. Do the math. There are 6 billion people on earth today. Say that just a mere 1 million of them choose to time travel on any given day. In 1 year they will make 365 million trips. In the past 2000 years there have been 730,000 days. Make it 10,000 years there have been 3.65 million days. So, in one year 100 people could have visited every day in the last 10,000 years. Now do that again for next year. And the year after that. And after that one. And so on. In 10 years you would have 1,000 people visiting every day. Now consider that ALL future people could do this simultaneously. Nevermind extrapolating this for 1 million years. Just 1,000 years of future civilization doing this would put us up to our armpits in future time travelers. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 7, 2009, 6:09pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/30 "2009-01-07T18:09:09Z")
> [@Whack-a-Mole](#): > > Do the math. > Now consider that ALL future people could do this simultaneously. Nevermind extrapolating this for 1 million years. Just 1,000 years of future civilization doing this would put us up to our armpits in future time travelers. So, you have an infinite number of folks doing something trivially easy and visiting a finite region of time/space. Whoop de doo. Put some practical considerations into time travel and get rid of an infinity or two (or maybe even only one or maybe even none) and again, you wont be up to your armpits in time travelers. And THAT even ignores the possibilty that maybe time travelers dont go around with signs on their foreheads in the first place. ---
**Author:** ![Strassia](https://avatars.discourse-cdn.com/v4/letter/s/e8c25b/32.png) [@Strassia](https://boards.straightdope.com/u/Strassia)\ **Post date:** [January 7, 2009, 6:57pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/31 "2009-01-07T18:57:16Z")
> [@dedmonwakin](#): > > That’s confusing… If this device was activated, you would have never really left the time or physical spot with which your in? Basically still left with a theory? What about it’s ability to move forward? Is it limited as well or is that an impossibility in that theory? That reminds me of that kid in school who claims to be faster than the eye can see,…“Wanna see?..See…I told you I was fast…you shouldn’t have blinked!” > > I am curious about this theory. Think of it as building a tunnel in time. You could not turn a dial and go to date X, instead you, for example, create a wormhole that instantly transports you from one point to another and nothing else. The theory goes, you move one end at near the speed of light for 50 years (say 26 light years out and back), then when you are done, you could step into it and return to some point close to 50 years before. If you started moving the wormhole in 2020 and the time dilation was 45 years, for example, starting in 2025 you could move back and forth to 2070. Both ends of the wormhole continue to move through time at 1day/day, just like us, so in 2030 you could go to 2075 and so forth. Another option would be if you could only change the rate you move through time inside some chamber. You could go in and move forward or backward, but you could not go to a point the chamber did not exist, or possible even through a point the camber was occupied. > [@Bricker](#): > > Feynman discussed auditing a philosophy class one day, and in an effort to understand a concept they were discussing (“essential objects”) he asked: “Is the inside of a brick an essential object?” His goal was to discover whether “essential objects” included theoretical constructs; he was going to point out that no one has ever seen the _inside_ of a brick, because the moment you break the brick, it’s half a brick with a new _outside_. The idea that a brick has an inside is basically a model, a useful concept to understand and predict the nature and behavior of bricks. > > All of science, all of our understanding of the universe is based on the idea of a model. I’m sure the first “law of gravity” said something like, “Objects fall at such-and-so rate of speed.” That was a useful model, because it accurately described the behavior of objects. As time went on, we refined it to note that air resistance could change the speed of falling objects. Still later we refined it again because it turns out that objects fall at different speeds on the moon, and relative to a space capsule in orbit they don’t fall at all. The best model, we declared, is that any two objects are pulled towards each other with a force proportional to the product of their masses divided by the square of the distance between them. > > I say all this only to say that it’s possible, at some point in the future, we may discover a circumstance in which F=GM[sub]1[/sub]M[sub]2[/sub]/r[sup]2[/sup] is no longer the best model, and if we find ourselves thus, we’ll revise the model to deal with the new circumstances. That’s the essence of the scientific method. > > Now, time travel. > > Time travel undercuts a basic assumption that allows us to manage the scientific method: the law of cause and effect. I’m not going to say that time travel backwards is utterly impossible – but it’s nearly so, because if it isn’t, then every single thing we think we understand about the way the universe works will have to be revised. The change of the model, in other words, would be vast and its implications dramatic. We have neither the language nor the analytical tools to approach it. Not being able to conceptualize something is a human limitation that we are still plagues many wrt quantum mechanics. Temporal theory may some day have as large a conceptual shift. > [@Frylock](#): > > There’s a time travel problem I’ve never seen addressed. It’s kind of an engineering problem. Suppose travel backwards in time is just like travel forwards in time, but backwards. (I.e., no teleportation through time, but rather, smooth continuous travel backwards along the time dimension.) Then when a body begins to travel backward in time, it seems like it should sort of “collide” with its heretofore forward-moving self. I don’t know exactly what the result of something like this would be. > > -FrL- > > ETA: This is the only real problem I had with the mechanics of time travel in the movie _Primer_, and I shouldn’t call it a “real” problem since in almost any time travel story I’m going to have to suspend _some_ kind of disbelief. Pulling from memory, I remember something from a physics popularization (I can’t remember which one) that showed that if you reverse the time direction, matter becomes antimatter. The simple example they used was a electron/positron creation and destruction. This is a common subatomic event that consists of a photon of energy greater than 1.02MeV generating a positron and and electron which exist for a short period and then annihilate together to generate a new photon. According to the book, the same series of events can also be thought of as one particle circling in time, looking like an electron to us as it goes forward, and a positron as it goes back. Photons look identical going either direction, so the two photons can be thought of as acceleration photons. Also, on the subject of instantaneous transportation to any point in time, which is what we are really talking about here, there are three possible effects [ol] [li]Alternate universes, which have been addressed to some extent.[/li][li]Unstable time loops, meaning if you go back and kill your grandfather something will happen to the universe that would erase either just that change or a lot more up to including the universe[/li][li]A stable time loop. If this is the case, nothing you do in the past can make a change on the future because it already happened. If you go back to kill your father you will fail, because you already did. Maybe you can’t do it, maybe you kill the wrong guy, maybe you have a malfunction, but what ever it is already happened.[/li][/ol] i would also suspect that time travel will be even more limited than interstellar travel. We could have already sent out a ship that will some day make it to Alpha Centuri, but it would have taken a concerted effort of the whole world for the last fifty years. Even if it is possible, it may be so resource intensive that it is almost never used. One proposed method I read required two perfect spheres, each with a mass close to the entire solar system, with opposite infinite charges micrometers apart without touching. Someone draw up an estimate and lets start taking bids! Jonathan ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 7, 2009, 7:02pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/32 "2009-01-07T19:02:07Z")
Imagine this. Sometime in the future we have 10 billion people on earth. The population stays constant. Time travel becomes possible. Our growth/economy is such that we can send a million people ever year somewhere/sometime and keep a constant 10 billion. People have a finite lifespan. Our future and society lasts for infinity. The universe never dies. These time travelers can pick anytime to visit (perhaps even future OR past). The whole infinity of “our future” PLUS the xyz billions of year of “our past” that had not yet developed time travel. My mathematical WAG is that this means that at any particular time (on average) you have one million out of 10 billion time travelers in any particular time, or one outa 10 thousand. Any mathematicians care to way in at this point? A good fraction to be sure, but not an ever increasing number due to infinite growth of the future time. Make the future finite, or the life of our civilization finite, destinations other than earth possible, time travel resource/energy intensive, not a particularly attractive/popular pastime, or times other than “now” much more attractive (or even known for that matter), and time travelers will certainly NOT be over running the local starbucks… ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [January 7, 2009, 7:03pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/33 "2009-01-07T19:03:43Z")
> [@Paleface](#): > > Impossible. Why? Time doesn’t really exist. Time is nothing more than a unit of measure created by mankind, just as the “inch”. Neither minutes or inches exist. But time does. Just because units of measurement are arbitrary or semi-arbitrary doesn’t mean that what they measure is imaginary. And time is as real as rocks. ---
**Author:** ![Frylock](https://avatars.discourse-cdn.com/v4/letter/f/ce7236/32.png) [@Frylock](https://boards.straightdope.com/u/Frylock)\ **Post date:** [January 7, 2009, 8:34pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/34 "2009-01-07T20:34:40Z")
> [@Strassia](#): > > Pulling from memory, I remember something from a physics popularization (I can’t remember which one) that showed that if you reverse the time direction, matter becomes antimatter. The simple example they used was a electron/positron creation and destruction. This is a common subatomic event that consists of a photon of energy greater than 1.02MeV generating a positron and and electron which exist for a short period and then annihilate together to generate a new photon. According to the book, the same series of events can also be thought of as one particle circling in time, looking like an electron to us as it goes forward, and a positron as it goes back. Photons look identical going either direction, so the two photons can be thought of as acceleration photons. Oh yeah, that’s right, I’d read that too now that you remind me of it. So as soon as someone tries to travel backward in time, they’ll just explode, taking a good chunk of the planet with them. Let’s not. 😛 -FrL- ---
**Author:** ![photopat](https://avatars.discourse-cdn.com/v4/letter/p/e95f7d/32.png) [@photopat](https://boards.straightdope.com/u/photopat)\ **Post date:** [January 7, 2009, 10:36pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/35 "2009-01-07T22:36:35Z")
My understanding is that Sci-Fi time travel is _theoretically_ possible, but requires such enormously enormous amounts of energy that it’s impossible in any practical sense. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [January 7, 2009, 11:32pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/36 "2009-01-07T23:32:54Z")
> [@billfish678](#): > > Imagine this. > > Sometime in the future we have 10 billion people on earth. The population stays constant. Time travel becomes possible. Our growth/economy is such that we can send a million people ever year somewhere/sometime and keep a constant 10 billion. People have a finite lifespan. > > Our future and society lasts for infinity. The universe never dies. These time travelers can pick anytime to visit (perhaps even future OR past). The whole infinity of “our future” PLUS the xyz billions of year of “our past” that had not yet developed time travel. > > My mathematical WAG is that this means that at any particular time (on average) you have one million out of 10 billion time travelers in any particular time, or one outa 10 thousand. > > Any mathematicians care to way in at this point? > > A good fraction to be sure, but not an ever increasing number due to infinite growth of the future time. > > Make the future finite, or the life of our civilization finite, destinations other than earth possible, time travel resource/energy intensive, not a particularly attractive/popular pastime, or times other than “now” much more attractive (or even known for that matter), and time travelers will certainly NOT be over running the local starbucks… You have to remember to add up all people over the whole future you are talking about. Assume 10 people in the year 2010 want to come back to today. And 10 people from 2011. And 10 from 2012. To us it they all would pop in simultaneously (or today at least) and we’d see 30 people from just that example. Now extrapolate that for the whole of the future. Let’s say just 1 million people per year time travel and cap the future at 5 billion years (if you have an infinite future then you have infinite people). That is 5,000,000,000,000,000 (5 quadrillion) people waiting to go somewhere in time. Let’s say they can go anywhere in that 5 billion year timeframe. That gives them 1,825,000,000,000 (1.825 trillion) days to choose from. That gives us 2740 people per day from the future. So in this case we probably would not notice them as in 10 billion people that would be a drop in the bucket. However, I doubt the future people would all evenly spread out. Presumably they’d want to go to better times or more interesting events. So you’d see clustering. Maybe around 9/11 or maybe when Jesus was performing his miracles or maybe to see the pyramids built or maybe to see the first space elevator or when the Martians attacked or whatever. In any given year there are only a handful of events I would think a time traveler would care to come back and visit. Maybe not even every year. From a perspective of 5 billion years it’d have to have been some pretty big deal to be remembered to come back to. I think clustering would be significant and you’d start noticing those 5 quadrillion people packing in around big events. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [January 7, 2009, 11:39pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/37 "2009-01-07T23:39:09Z")
> [@Whack-a-Mole](#): > > So in this case we probably would not notice them as in 10 billion people that would be a drop in the bucket. However, I doubt the future people would all evenly spread out. Presumably they’d want to go to better times or more interesting events. So you’d see clustering. Or not. If one postulates the type of time travel where going into the past creates a new alternate universe, then each location gets one time traveller ( or one group if they arrive together ). Instead of a billion time travellers watching Jesus get crucified, you have a billion alternate versions, each with one time traveller watching him get crucified. ---
**Author:** ![billfish678](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@billfish678](https://boards.straightdope.com/u/billfish678)\ **Post date:** [January 7, 2009, 11:51pm UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/38 "2009-01-07T23:51:37Z")
> [@Whack-a-Mole](#): > > You have to remember to add up all people over the whole future you are talking about. … . You dont get it do you? If there is an infinite amount of future AND and infinite amount of past/future to visit there will be a FINITE amount of time travelers deposited at any given time if the number of time travelers leaving their particular time at any given is FINITE. Given that time travel probably requires some energy/mass/resources to pull off, the number of time travelers leaving any particular time for any other time MUST BE FINITE. Therefore, the number of time travelers existing at some “visited time” must be finite. ---
**Author:** ![Magiver](https://avatars.discourse-cdn.com/v4/letter/m/4491bb/32.png) [@Magiver](https://boards.straightdope.com/u/Magiver)\ **Post date:** [January 8, 2009, 12:00am UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/39 "2009-01-08T00:00:13Z")
The problem with time travel is that it would displace matter. But since Steven Wright already claims to have moved through time who am I to argue. ---
**Author:** ![begbert2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/begbert2/32/3357_2.png) [@begbert2](https://boards.straightdope.com/u/begbert2)\ **Post date:** [January 8, 2009, 12:02am UTC](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178/40 "2009-01-08T00:02:34Z")
> [@billfish678](#): > > You dont get it do you? > > If there is an infinite amount of future AND and infinite amount of past/future to visit there will be a FINITE amount of time travelers deposited at any given time if the number of time travelers leaving their particular time at any given is FINITE. > > Given that time travel probably requires some energy/mass/resources to pull off, the number of time travelers leaving any particular time for any other time MUST BE FINITE. > Therefore, the number of time travelers existing at some “visited time” must be finite. So? “Finite” includes some pretty large numbers. How many time travelers need to come back and try to kill every dictator or unpopular world leader before we noticed it happening? (And there will never be an infinite amount of time to visit - merely a large finite amount of time that gets larger as you go. Not that that’s all _that_ relevent to your point.) [Previous page](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178.md?page=1) [Next page](https://boards.straightdope.com/t/time-travel-possible-or-impossible/480178.md?page=3)