As it turns out, Time Travel is possible! It's just not as useful as we thought it would be, that's all. You can only go back in time, and not really. Whenever anyone goes back in time, a pocket Universe is created that perfectly mimics that time period as it existed in our reality, people and everything.

It's all as 'real' as our Universe, but it only exists in an alternate dimension and only for as long as someone from the 'real' Universe is there.

The people that go in can come back out whenever they want, though it does take a really fancy machine to send them in, and you can't take anything out of the alternate dimension other than the memories. When you come back out it's almost as if no time has passed at all, so your body is pretty much untouched.

We've just been using it to satisfy our curiosity, but I'm wondering... what else could we do with it?


closed as primarily opinion-based by Aify, Gryphon, RonJohn, JBH, Vincent Aug 3 '18 at 19:14

Many good questions generate some degree of opinion based on expert experience, but answers to this question will tend to be almost entirely based on opinions, rather than facts, references, or specific expertise. If this question can be reworded to fit the rules in the help center, please edit the question.

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    $\begingroup$ Research ancient history or the start of the universe, or as a video game where you can enjoy an alternate life. $\endgroup$ – Tyler S. Loeper Aug 3 '18 at 14:13
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    $\begingroup$ can only one person travel, or can a whole group travel? $\endgroup$ – Kepotx Aug 3 '18 at 14:18
  • $\begingroup$ @Kepotx A whole group can travel if they want. $\endgroup$ – Onyz Aug 3 '18 at 14:18
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    $\begingroup$ Can anyone else travel to the same pocket after you've departed from the future? $\endgroup$ – Iron Gremlin Aug 3 '18 at 17:20
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    $\begingroup$ "What wlese could we do with it?" is very open-ended. How will you choose the best answer? What criteria allows us to focus our responses? Please read what it is to have a primarily opinion-based question. $\endgroup$ – JBH Aug 3 '18 at 18:01

The impact would be huge.

Secrets would no longer exist. Passwords, social security numbers, PIN codes, all become meaningless. People would just beam behind you to a time where you used the password/social security number/PIN code, and read over your shoulder. Worse, because it's a pocket universe, you don't even know someone snooped your secret since it happened in a copy of the universe.

OTOH, crimes would be harder to get away with. Cops could just go back in time and see who committed it -- and a trial would mean a field outing back in time for the judges, juries and lawyers.

Try keeping your affair a secret...

But, you can revisit that girlfriend who broke up with you, play again with the pet which died last year, and have a chat with your great-great-great parents who died long before you were born.

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    $\begingroup$ "Getting away" with a crime would change from the current "conceal who did it" to "conceal when & where it happened (and also who did it)." They can't time travel to it if they can't find it. $\endgroup$ – Walt Aug 3 '18 at 20:14
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    $\begingroup$ @Walt sure. But it's hard to conceal where a burglary took place. And while you may be able to conceal where a murder took place, an investigator could just start following the victim from when he/she was alive. Note also that anyone investigating a crime could go back in time as many times he/she wants, and stay there for as long as needed. Such a person could inspect thousands of possible places a crime may have been committed. $\endgroup$ – Abigail Aug 3 '18 at 20:31
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    $\begingroup$ Yup, I agree that it's harder to commit most traditional crimes. Digital crimes would still be relevant, and the insider trading that could be done with this tech by people that shouldn't even actually be insiders would give the SEC conniption fits. $\endgroup$ – Walt Aug 3 '18 at 20:37
  • $\begingroup$ @Walt The described time machine means you can basically reply the digital crime as often as you want. Which means, you can watch it when it happens, and put tools into place to help aid where it comes from before it actually happens. Even if the crime happens using many intermediate steps, you can, at your leisure, unravel it step by step. $\endgroup$ – Abigail Aug 3 '18 at 22:01
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    $\begingroup$ How much is the investigator paid for time spent in an alternate reality? How much does it cost to put him there to begin with? I admit there would be a major economic shift regarding jobs that can be done in alternate realities, because suddenly effort can be spent without technically spending any time, but I think in the end that labor wouldn't be free, and thus you can't really assume infinite time to solve each crime. $\endgroup$ – Walt Aug 3 '18 at 22:07

Make a huge bounce in history

Do time travel to speak with historical figures? Damn, that's the dream of any historian or newspaper. Imagine how valuable an interview with Cesar, Jesus or Ghengis Khan would be. You could also know the exact location of cities, artifacts and such. You would be able to study what daily life was like as you could never hope to before.

Infinite amount of time

When you come back out it's almost as if no time has passed at all, so your body is pretty much untouched.

This is also very valuable. If anyone (or a whole group) needs time to think about something, meditate, or do anything else that takes time, they can do it this way. Some conflicts are hard to resolve, but with an infinite amount of time? I'm not saying it would solve everything, but time is one of the limitation of negotiations.

Trip company

You are burned out and need some vacation? HistoryTravel is here for you! For a few thousands dollars, we offer you a long trip during whatever time period you want. Do you prefer a gladiator combat, or being a crusader knight? With HistoryTravel, you can do whatever you want!

Seriously, travel in time would make really good holidays. Sure, only the rich people could afford it, but there is a huge market. Bonus point: you can do it during your lunch time.

Fast formation

Another advantage of having more or less infinite amount of time: You could study whatever you want. Either bring a teacher and a class, and you could learn, for example, a new language. Even if it takes several years in the pocket universe, from perspective of the current world, you enter the machine during the morning and come out the same day knowing how to speak German.

Even better, you're travel in time, so you could go to university and study with historical figures, such as Einstein.


Want to know what happen if WW3 happened today? Want to know what would happen if you ask your crush out? Want to do some crazy dreams that costs all your money? Well, you can. Just enter your pocket universe close to today's date, trigger what you want and grab some popcorn. Basically, if you can travel to yesterday and then stay in your pocket universe for ten years, you can do a forward travel. Don't forget to bring back some ideas for new technologies.

You could also experience near past things such as in abigail's answer.

  • $\begingroup$ Practice asking out your crush until you have the perfect approach. $\endgroup$ – Tyler S. Loeper Aug 3 '18 at 16:28
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    $\begingroup$ Human nature, given what it is, would very quickly move some toward acting out dark and even sinister fantasies. And what if those fantasies with real but not really real people no longer satisfied the cravings? Would those people begin acting out those desires in the real world? Would people forget which world they were in? Would people lose their minds, their sense of self, their sense of purpose? This is a rich world for story telling. $\endgroup$ – Tracy Cramer Aug 3 '18 at 16:51
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    $\begingroup$ @TracyCramer You don't like video games very much, do you? $\endgroup$ – Walt Aug 3 '18 at 17:23
  • $\begingroup$ @Walt, I play video games every day. Perhaps we could have a chat so I could understand what you're hinting at. $\endgroup$ – Tracy Cramer Aug 3 '18 at 18:00
  • $\begingroup$ @TracyCramer I think the implication was that you probably disliked video games, particularly ones in which you engage in sinister acts, due to thinking they encouraged such acts in real life. Though, I see your point of a distinction in this case $\endgroup$ – Piomicron Aug 3 '18 at 18:33

Use your backwards only time machine to predict the future:

Here is just a thought.

You have mentioned that when you use the time machine, that it creates a new identical universe for you that disappears when you leave. But when you leave you return to your current universe and arrive at the same exact time as when you left, but without having aged at all.

So here is my proposition. Use your time machine to scout out the future. Set your time machine to travel one second back into the past. By the rules you have suggested, you are now in an alternate universe that is identical to your own. The current time in this new universe is almost the same as your original one. So if this universe is really identical to the one you just left, then that means that future events in here will be the same as they will be in your original universe.

I am sure you see the benefit here. You can camp out as an informant carefully keeping track of future events. When you have enough information, return back to your own universe and now you will know what happens in the future. World war 3, we know when it happens. Those troop movements? We have them. Lotto tickets? We have all the lotto numbers.

You get the idea. The military might be interested in this the most.


In addition to @kepotx's very astute answer, another choice would be to attempt to accelerate technological growth and predict the actual course of human events. Take a whole bunch of modern computers and seminal texts on computation to the faculty of MIT circa 1973, and they will quickly catch up to where we are today, and likely come up with novel solutions. Might it take twenty or thirty years? Yes, but with such revolutionary technology, you will likely attract the knowledge of the greatest minds of the day. They will likely come up with ideas not yet created in our modern day. When you exit, you will likely have novel information which has yet to be obtained, and you can slingshot tech forward. Similarly, if it is possible to visit multiple points, you could even bring a sizeable number of technologies to the distant past (200 years?) and visit that world 100 or 150 years later, and see if people have come up with anything new that hasn't been invented yet.

Basically, you'd be leveraging the collective consciousness of humanity in the past. Pretty neat. Could also go and mess with great authors and great thinkers of previous times and see how their works change. Results would likely vary, but who knows what they would've come up with in better circumstances.


Find lost or buried artifacts, treasures, etc.

What happened to the Nazi Gold? Go back in time and follow the relevant Nazi's around to find out. Are there hidden treasures or historical relics still hidden in the Great Pyramids of Giza? Perhaps--the easiest way to find out is to go back and watch while they were being built or furnished.

Beyond these two examples, there are any number of supposed lost treasures (see e.g. this top 10 list). Some of them are probably apocryphal, others already looted in years past. But some are probably real and still there. If you could figure out where they were placed back in history using the time machine, you could use the memory to recover them in modern day. Instant riches!

Besides opportunities for wealth, there are a number of cultural or historical artifacts would enhance our knowledge if they could be found. For instance, perhaps there is another trove of early Christian documents like the Nag Hamadi texts buried somewhere in the desert. Who knows when or if they'd ever be found by accident, but if you know where to look...


Weight Loss

Oh man, you've just made a great weight loss machine. Or a death sentence. Since you can't take anything out, anything you eat while there will stay there. However you're still going to be burning calories, and excreting, exhaling and otherwise shedding matter everywhere you go. So when you come back, all the matter you ingested will stay there. Meaning you get the benefits of all the exercise performed during your stay, without accumulating any weight from the matter you consumed while there. Of course, this could be fatal or injurious if you spend too long and have too much of your "real" matter replaced with pocket-matter.


Eternal Life

I find the time compressing element of your scenario the most valuable. Unbound time passes from the first-person view, but no time at all passes in the second-person (real time as experienced by your body). This could allow someone to live a full life to near death, then pop into the machine, rewind to the distant past and relive countless additional lives. This traveler would only really need to stop when they had grown weary of living. You wouldn't even have a resource constraint, because grandpa's countless eternities are not "hogging up the time travel machine", they all happen instantaneously.


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