Let us assume humanity, in the near future, acquires the technology to look and listen into the past without being able to change any of it, but it is very complicated and even more expensive, so, for instance, this can not be used to solve crimes. Would any historic events actually be investigated? If so, who would pay for which research, e.g. would the Christian churches invest a fortune in trying to get actual proof of Jesus of Nazareth?

To narrow it down, assume a cost of

  • up to a trillion bucks (in today's dollars/pounds/euros) over ten or more years to set up the initial global system,
  • a billion bucks over a year or so to set up each recording and
  • at least a million bucks for postprocessing every minute of raw recorded data.

The result would be like a video filmed from the sky with TV quality of the 1980s. The resolution would be good enough to identify individuals as far back as c. 2000 years but degrades with increased temporal distance.

Since basically no single state or other entity could finance the initial system alone, but even some individuals could pay for recording a single event, the question is really twofold:

  1. Would the system be build at all by international cooperation, like the ISS or ITER?
  2. Who would have an interest in specific research and the resources to fund it?

closed as primarily opinion-based by Mołot, kingledion, sphennings, Vincent, L.Dutch Dec 31 '17 at 3:11

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.

  • $\begingroup$ Just as a comment: Pretend they went back and found that Jesus of Nazareth did not exist...the whole Church would go into turmoil, wouldn't it? And if Jesus of Nazareth did exist, so what? I don't think the Church would be particularly interested in going back in time. How about a different more practical example? I'm interested to hear what else could be important for us. $\endgroup$ – NL628 Dec 30 '17 at 22:23
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    $\begingroup$ The mainstream (a.k.a. apostolic) churches don't really care whether there actually was a dirt-poor carpenter's apprentice called Isa bin Yusef al Nazri in 1st century Palestine or not; they work on doctrine, tradition and faith. ("My kingdom is not of this world", John 18:36.) So the question is, would the Newly Reformed Born-Again Southern Baptist Church of America put one thousand billion dollars U.S. (plus change) on a bet which they would run a significant risk of losing? $\endgroup$ – AlexP Dec 30 '17 at 22:26
  • $\begingroup$ @AlexP upvote for the "(plus change)" $\endgroup$ – NL628 Dec 30 '17 at 22:27
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    $\begingroup$ Since this has devolved into a comment war about the existence of Jesus, I'm voting to close. Flame wars over religion are not on topic for this site. Try to stick with less controversial topics in the future. $\endgroup$ – kingledion Dec 31 '17 at 0:00
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    $\begingroup$ Well, we’d finally be able to decide what dinosaurs looked like $\endgroup$ – Dubukay Dec 31 '17 at 0:00

I'll put in an order or two;

Personally I think that this kind of technology would be predominately used to solve lost technology or scientific understanding issues. Take for instance the Ionian Empire, a Greek 'tribe' whose writings showed that more than 5 centuries before the Birth of Jesus they had figured out that the earth was a globe and that it orbited the Sun. Most of their mathematics was wiped out by the Pythagoreans and yet given what they were able to realise so early, perhaps there is a lot more that they could tell us if we could get a hold of images of their work.

If there was some way to get a hold of imagery of Fermat at work, perhaps we would have found that 'interesting proof' of his last theorem. True, it's now been solved, but using 21st century maths. How did he do it without that math? What have we missed that could (potentially) lead to new branches of mathematics that could perhaps even simplify quantum theory for us?

What about Carthagenian maths? Sure, they were a trading nation but it was said that their maths was superior to Roman mathematics in many respects, although not much of it was left after the Punic wars. Perhaps there is something there that we could see that could lead to a new way of approaching certain problems?

If you want a more recent and practical answer, what about Nicola Tesla; he had invented ways of directly transmitting energy that he never wrote down and which were lost to this world upon his death (and perhaps even earlier with the destruction of his laboratory). How did he do it? We still haven't figured that one out and it would be a massive benefit to our society to know how to do that.

This would be a scientific endeavour, so it makes sense that the problems that are solved in history are scientific in nature. In that sense, recovering ancient mathematics that has been lost to us seems like the perfect approach to take; our mathematics today is very powerful, but very complex. If some new approaches are rediscovered, perhaps we could build upon them to create new approaches that we can't perceive yet. This seems to me to be the most likely use for such a tool, and the most beneficial to our society at the same time.

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    $\begingroup$ Many questions could be answered using this technology. How did the various strata of Latin actually sound in the mouths of Cicero and the cur in the street? What was the grammar and speech of Carthage & Egypt like? What did the Greek pitch accent actually sound like? What were the works kept in the Great Library at Alexandria? What did Rome and Antioch and Alexandria actually look like? What did the pyramids look like? The hanging gardens? How was qipu read? What did the Battle of Lepanto look like? How did ordinary Parians of the 15th century live? $\endgroup$ – elemtilas Dec 31 '17 at 1:49
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    $\begingroup$ I fear that all we would learn was that the Ionians could do basic trig, Fermat though his method for n=4 could be generalised, then realised it couldn't but never went back and corrected his marginalia, and Tesla starting to believe his own hype. Perhaps I am overly cynical.... $\endgroup$ – James K Dec 31 '17 at 2:04
  • $\begingroup$ @JamesK; you may well be overly cynical, but that doesn't mean that the possibilities that you mention wouldn't be realised. Even if they were though, that would tell us something. Ultimately, it's about perspective; what did others know that we think we've forgotten? Even if the answer is nothing then that assures us we're on the best path we can find and that's helpful. Right now it's not so much the right path as the only path and verifying that path through alternate perspectives seems to me that it would be money well spent. Perhaps I'm overly idealistic. :) $\endgroup$ – Tim B II Dec 31 '17 at 2:27


Find out exactly what Silphium is, and if any still exists. Silphium was an effective form of herbal medicine and birth control in the roman states. It even had its uses in cooking. It is believed to have been harvested into extinction but no one is sure since so much information has been lost. We think it is part of the fennel family but it was so ubiquitous no one bothered recording much information about it so we don't know if it is one of the extant species. Any pharmaceutical company would be willing to pay on the chance of acquiring the source of many potential drugs. A agricultural company might be willing to chip in for similar reasons. I could easily see Monsanto and GSK deciding to throw in together to try and find a potential source of many new medical compounds.

  • $\begingroup$ Dude, if you want silphium, go buy some fennel at the grocery store. Come on, use Occam's razor here. Is it more likely that silphium is actually extinct or has just been renamed to something else.... $\endgroup$ – kingledion Dec 31 '17 at 2:30
  • $\begingroup$ Either is likely, humans are not known for caring if they harvest something to extinction. Either way finding it would be worth quite a lot, finding a new set of drugs would be worth a fortune. Just becasue it is in the fennel family does not mean other species are identical or contain all the same compounds. $\endgroup$ – John Dec 31 '17 at 14:56

Focus the device around Roswell, New Mexico during the first week of July, 1947. If anything unusual (a.k.a. unidentified) appears, refocus the device backwards along its incoming path to see where it came from.


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