9
$\begingroup$

You've traveled back in time 65 million years, with no way to return. What evidence can you leave to ensure future humans will know of your existence?

$\endgroup$

migrated from puzzling.stackexchange.com Dec 8 '16 at 16:05

This question came from our site for those who create, solve, and study puzzles.

  • 2
    $\begingroup$ An interesting question, but I don't think there is anything one person could accomplish in a human lifetime that would survive 65 million years. $\endgroup$ – kingledion Dec 8 '16 at 16:17
  • 3
    $\begingroup$ @kingledion - What about dinosaur turds? I think there's plenty a human can do that could survive that long. Making it findable is the hard part.... $\endgroup$ – Snow Dec 8 '16 at 16:22
  • 4
    $\begingroup$ @Pete Of the billions and billions of dinosaurs each dropping thousands of turds over hundreds of millions of years, how many have been recovered? The chances of your particular turd (or your bones, for that matter) getting recovered are statistically insignificant. $\endgroup$ – kingledion Dec 8 '16 at 16:26
  • 2
    $\begingroup$ @kingledion - Precisely. $\endgroup$ – Snow Dec 8 '16 at 16:28
  • 2
    $\begingroup$ Supposing you could even guarantee that what you left would remain intact, and be discovered, what could you leave that would be seen as evidence of time travel? Wouldn't modern humans be more likely to attribute the discovery to a hoax, aliens, or a faulty dating process than time travel? $\endgroup$ – Mathily Dec 8 '16 at 16:42

11 Answers 11

7
$\begingroup$

This is very dependent on the technology you have available.

Given enough tech my approach would be retroreflectors on the moon. Build in as much redundancy as you can, both in the number of reflectors and how each is set up.

Each reflector has a gold wire coming off it leading to a buried capsule containing your messsage etched in metal foil, layered with a different metal so the whole thing doesn't just weld together.

If I couldn't get to the moon my second choice would be to head to Namibia and hope the desert there already exists.

If so I would go to a point deep in the desert and bury several message capsules. I would then make a ring around this many miles out. Drill a deep hole, place in it a tube. On the bottom is a lump of U-235, on the top is another lump. There is a support holding that upper lump that has radioactive material incorporated into it such that the decay slowly weakens the support. Calibrate these to break in 64 million years. (Of course this won't be perfect, the actual failures will occur over time. If you can be precise enough edge it closer to 65 million years) If the tube is undamaged when the support breaks there is a decent chance you get a nuclear detonation.

(BTW, for those who think you need something more complex: This is not a reliable bomb, you have a decent chance of a fizzle. It also must be U-235, a Pu-239 bomb like this is a certain fizzle, not to mention that your Pu-239 bomb will have long since decayed. However, if even one explodes it will be noted and fizzles will be found.)

In time somebody is going to discover the remains of your bombs. While natural nuclear reactors exist there's no known way to get a natural nuclear detonation. Thus even the discovery of one bomb crater (remember, the craters aren't all that old, they'll be much more visible than anything you did 65 million years ago) proves intelligence at work and would trigger a major effort to figure out what's up. If you get three detonations you provide an indication of the location of your buried messages.

$\endgroup$
  • 1
    $\begingroup$ Difficult but incredibly clever. +1 $\endgroup$ – Zxyrra Dec 9 '16 at 4:20
  • 1
    $\begingroup$ Why all the way out to the Moon? Put the retro-reflector in an Earth orbit instead. Also make some of the faces non-reflective, and rotate it. You will have a passive blinking beacon in orbit. This will attract attention. $\endgroup$ – MichaelK Dec 9 '16 at 10:35
  • 1
    $\begingroup$ @MichaelKarnerfors If you leave it in orbit it's much more likely to end up knocked out of orbit at some point. And there's no guarantee anyone will shine a laser on it if it's in orbit. A radar retroreflector will have a much shorter range limit than an optical one and if you don't put it awfully high it's going to come down in the intervening 65 million years. $\endgroup$ – Loren Pechtel Dec 9 '16 at 21:24
7
$\begingroup$

This was originally posted to the Puzzling SE, which means that the poster has a specific answer in mind.

Since they chose the odd value "65 million years" instead of a round number, it is probable that the intended answer is:

You should cause the Cretaceous–Paleogene extinction event.

$\endgroup$
4
$\begingroup$

The problem with this question is you don't say what I have available to use to send a message. If I have no modern tech, I'm probably dead before I can leave anything that lasts a few years, let alone millions. Bacteria, animals way more experienced in eating other animals, unknown flora, lack of safe food supplies... I'm in too much trouble to worry about sending a message, I'm just trying to survive the night.

If, however, I'm a fully equipped traveller from the future with food and medicine enough to last a while, I would probably do what that one answer on the dupe question suggested and smelt gold and silver into coins and scatter them all over the North American Craton in hopes one might be found. Of course, Gold and Silver are nice for chemical stability, but not very sturdy for mechanical stress, so if I was able to smelt steel I might do the same with steel roundels and ingots. I'd have to find some nice, boggy place to put my stuff, and hope somebody finds it... I'm kinda lucky, because humans have all of future history to find it.

The best way to send a message forward from 65m years ago? If I have the ability to travel back in time, with any luck I've got the technology to easily achieve orbit. Using my advanced computer from the future, I'd compute a trajectory that would put a microsatellite in the vicinity of Earth in 65 million years, and hope I have the delta-V to put it there.

Or, if I have the Delta-V, I'd try to put a metal or stone tablet at a Lagrange point; then I'd hope that somebody in the future would put a probe or park a ship there and wonder what that artifact is floating nearby. With any luck, the solar wind wouldn't have destroyed my message.

The key, though, is that 65 million years is a long time.

$\endgroup$
  • 4
    $\begingroup$ If I was a fully equipped traveler there'd be a lot of questions to answer about my camper van in the fossil record. $\endgroup$ – Separatrix Dec 9 '16 at 8:19
4
$\begingroup$

The real question is would anything be left after that long? Even metal alloys would erode incredibly in that time. Even so if you made them unmistakably intelligent shapes, it still could be un-recognizable by then. There is a chance if you made enough of the same shapes, and scattered them around the globe there would be evidence left. Personally I like the Mt. Rushmore effect. So my answer is spend your entire life, aside from time spent surviving, carving and breaking the biggest rock formation on earth, and then spend even more time burying the formation in sand and dirt. If you made a sign or symbol in the rock that was large enough, maybe even carved out of a mountain, it might just stay. especially if you buried it hoping that humans would detect it later with some sort of sonar or infrared device, we use those devices nowadays to detect oil and mineral deposits.

$\endgroup$
  • 2
    $\begingroup$ en.wikipedia.org/wiki/Amber#Geological_record - "The oldest amber recovered dates to the Upper Carboniferous period (320 million years ago)" - so certain things may lasts for long time - just dip messages in to the resin $\endgroup$ – MolbOrg Dec 9 '16 at 1:19
  • 1
    $\begingroup$ To go along with @MolbOrg 's comment, there was a recent article about finding an intact dinosoaur tail. I would advise, however, to leave LOTS AND LOTS of such amber messages. $\endgroup$ – Draco18s Dec 9 '16 at 6:17
  • $\begingroup$ @Draco18s woow, that just super, lol, excellent $\endgroup$ – MolbOrg Dec 9 '16 at 9:55
3
$\begingroup$

Forget metals. Gold aside, none will last 65M years. Instead, think fired ceramics.. A humble dinner-plate will survive until it is ground into dust by erosion or melted along with the rock it has become part of. It's a perfect techno-fossil.

You can easily mass-produce a message for the future using a mould or a stamp on your wet clay. Aim for quantity not quality, because you have no good way to predict where to leave your message tablets so they will survive and be near the surface 65M years hence.

That's it, really. Scatter them around and hope. We can be pretty certain there was no house-brick using dinosaur civilisation because no such fossil bricks have been found

BTW if you have the technology to make big hydrogen bombs, and are willing to unleash such on the environment, evidence of that should survive. Craters lined with trinitite and shock quartz, and various long-lived isotopes that are not found in nature. The fallout layer might be global and detectable, as was the Iridium from the vaporised meteor that killed the dinosaurs. But would you survive that fallout? And, you'd still need ceramic tablets to carry an actual message.

$\endgroup$
2
$\begingroup$

Just few things that can survive that long, and most of them are hard to do and require process like many had answered here.

But you can do something that's quite easy, not a hard thing to do (while it need something to be hard), and it's already imprinted on our DNA :

just breed. Fill the Earth with your offsprings.

And then tell your saga to your kids. For sure it would change the history of earth and mankind, but you get your message to the future anyway.

$\endgroup$
  • 1
    $\begingroup$ This is easier said than done if you are the only time traveler. I doubt you'll find Raquel Welch waiting for you if you go back 65 million years. en.wikipedia.org/wiki/One_Million_Years_B.C. $\endgroup$ – James Dec 9 '16 at 14:08
  • $\begingroup$ How would you suggest you breed when the nearest human female is ~62.5 million years away (assuming you can even breed with them, not sure if homo sapiens (~64.8m years away) or homo sapiens sapiens (~65m years away) might be needed for that)? $\endgroup$ – Annonymus Dec 10 '16 at 16:49
  • $\begingroup$ No, the question didn't stated that I was stranded alone. While many answer can take any future equipment (that even I don;t have access to it right now), Mine just take a human partner with (this almost everybody can have access to). $\endgroup$ – Hariz Rizki Dec 13 '16 at 15:11
  • 1
    $\begingroup$ @HarizRizki: Ok, I see your point. I wouldn't have posted my comment had you stated in your answer "...assuming you have a mate with you...". I guess another valid answer would be "You and the other 6 billion people who also went back in time with you can just die and at least one of your skeletons will surely be found." $\endgroup$ – James Dec 15 '16 at 13:50
2
$\begingroup$

In light of the feathered dinosaur tail that was found embedded in amber, I suggest you go hunting, then write a note, pin it to the dino, cover it in tree sap, and bury it.
Do this a bunch of times and wait.

You could also just write a bunch of notes and cover them in tree sap without the dinosaurs, but that's less fun.

$\endgroup$
1
$\begingroup$

Being from the present, you could know what artifacts survived through the years from memories of looking through museums and literature in your proper time. Also you would know the location of famous fossil digs, cave paintings etc.
This would enable you to pick sites with the most potential of being discovered. Lest your meddling interfere with history, definitely make many messages, but at least you know where and what has the best chances of being found, as you've seen it happen already.

$\endgroup$
  • 1
    $\begingroup$ how would you find out where you are? $\endgroup$ – Innovine Dec 10 '16 at 8:15
  • $\begingroup$ Almost all artifacts exposed in museums have yet to be made. The first homo sapiens sapiens (our species) is still ~65 million years away. It is doubtful you could even reach a historical site in your lifetime, assuming you didn't get thrown back in time with a solar-powered hovercar $\endgroup$ – Annonymus Dec 10 '16 at 16:54
0
$\begingroup$

Why not encode a joke (or something) into the junk DNA of a lifeform you knew would have its genome encoded in the future. Something so bizarre that it would attract attention.

$\endgroup$
  • 2
    $\begingroup$ Becuase DNA that's not used for a purpose will quickly mutate and be quite scrambled in that span of time. $\endgroup$ – JDługosz Dec 9 '16 at 6:38
  • 1
    $\begingroup$ I think you're overestimating mutation rates. How about some crocodile DNA? - 200 million years. And we share 50% of a banana's DNA. There's a fair lump that seems fairly immutable in Eukaryotes. But I'd defer to a lesser dilettante. $\endgroup$ – Hingehead Mar 7 '17 at 4:39
0
$\begingroup$

Assume your traveler bumped in the year 1999 (65m years before his original time).

What he can do to ensure his identity maintains for years and people of his time get to know his identity?

Short Answer:

Be Like Nostradamus!

Long Answer:

The traveler can sensationally opt to tell and share famous good or bad internationally known events which will occur after few years of 1999 BC. People of 1999 may not believe him until they see your first story coming true. Also the word "Sensationally" is important. People ought to remember things which are said in unique or unconventional ways.

For example: He tells people of 1999 about 9/11/2001 attack in NY something like this:

*Five and forty degrees, the sky shall burn:

To the great new city shall the fire draw nigh.

With vehemence the flames shall spread and churn

When with the Normans they conclusions try.*

(Source of these lines)

And in 2001 when the incident happens, you can start your marketing and publicity in full swing (indirectly via your devotees or friends of course). People will record and publish your predictions (stories) and will continue to pass on the same if the incidents he chose to tell actually kept on occuring in consecutive times.

I am sure, a future citizen of 65m years away may not even know about something that happened on 9/11/2001 but I am sure that few events stays in history textbooks for thousands of years. Take old scriptures and religious transcripts.

Your traveler can even inscribe your stories in monuments and such buildings which are mostly restricted or protected and have potential to stay for years. Even if these monuments gets damaged, their photos, transcripts and literature will be kept for future people to show them how their "ancestors" way of architecting was artistic (like Big ben or The Taj Mahal)

And if not textbooks or monuments, use people and generations to pass on your stories (and most importantly your identity which at some point of time will reach the right year to target person).

I bet metals and monuments may not stay for such a long time but folklore and literature does

$\endgroup$
  • 1
    $\begingroup$ I highly doubt anyone would even remember what 9/11 was in next 1000 years, not to mention 65m. $\endgroup$ – Mr Scapegrace Dec 9 '16 at 8:32
  • $\begingroup$ That was just an example. I am sure there must be several events which will always be remembered like first person who stepped moon, or something like that $\endgroup$ – Karan Desai Dec 9 '16 at 8:56
  • 1
    $\begingroup$ Yeah well for every Neil Armstrong there would be millions of dumbasses who will murk history "because it never happened, it's all fake, bla-bla-bla". The only facts that are immune to any kind of interpretation and/or drastic changes caused by new discoveries are math and maybe computer science. And these facts don't work that well with "Be Like Nostradamus!" $\endgroup$ – Mr Scapegrace Dec 9 '16 at 9:09
  • $\begingroup$ I question both the logistics of trying to predict the future from so far in the past (we don't have exact dates for anything pre-history, at least, it's narrowed down to a decade, and in some cases, even less accurately)--not to mention the "and who are you going to tell?" problem--and the validity of the Nostradamus example (the Wikipedia page itself goes into plenty of detail on how the passage more accurately describes Naples in 1139). $\endgroup$ – Draco18s Dec 9 '16 at 18:44
0
$\begingroup$

The only evidence you need it your bones.

There's a chance, sure that you will corrode away and not fossilize, however there's also the chance that you will. The best way to do it, would be to die.

That way you have a chance for future archaeologists to dig you up :)

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.