Proof that time travel is impossible?

This may be more appropriate for Great Debates, but let’s see how it does here.

While mulling over the possibility of time travel the other day, I figured that it’s obvious that anyone with access to a time machine would try and make a few quid/bucks/euros/lempira (delete as applicable) by going back in time and putting some bets on sporting events, lotteries etc, of which they knew the outcomes.

So, say the first time travellers just go back a day or two, and clean up. Soon, the bookies are going to start going out of business. Future (if that’s the right word!) time-travellers will end up having to go further and further back in time to find bookmakers that haven’t been ruined by earlier (for which read later!) time-travellers.*

The obvious conclusion seems to be that, if time travel is invented in the future, at least while humans are around, then we should already be over-run by time travellers betting on the future. In a nutshell: the continued existence of bookmakers proves humans will never master time travel.

Of course, there is the possibility that a time machine that will not permit travel back to before it was created could be invented, but aside from that is there an obvious hole in my thinking?

*I remember in the Hitchhikers Guide to the Galaxy books, Douglas Adams postulated that one of the chief hazards of time travel was the increasingly complex grammatical tenses it required, but that’s by the by…

Well, maybe the time travellers in the future realize that if they exhaust the Universe’s bookie supply, then time travel will cease to exist, because it’s impossible. Realizing this, they make a sort of agreement not to go back too far in time to make big bucks, because nobody wants time travel to stop existing. So, they never go back before a certain date, and there’s no problem!

** Achernar**, that’s art!


Good one. I hereby christen that point the Ladbrokes Event Horizon.

No, that wouldn’t work. If all the time travellers preyed on a narrow “window” of bookies, they would shut them all down within that window.

Alternate strategies are possible:

  1. Establish a gentleman’s agreement to a cap for winnings, so the herd is not thinned too much.
  2. Spread the winnings against bookies out over the widest possible time frame.
  3. If bookies are driven out of existence. send someone back to invent bookmaking earlier, and provide more prey.
  4. For a share of the profits, some travellers go back and reveals incredible knowledge to wealthy folk in the past. Convince them that the future can indeed be foretold, then convince them to place large bets, large WRONG bets. This allows the bookmaker himself to survive.

Can’t they all just play the lottery? How do you know that a percentage of lottery winners aren’t time travelers?

Don’t you think that if you invented a time machine, you could make so much money selling it to Boeing or Microsoft or somebody that you wouldn’t NEED to travel back in time to make even more?

Almost. You need to travel to prove it works.

THEN, you can pay have them pay you NOT to time travel. For instance, you could go back in time and file key patent applications before they did. Come to think of it, you could blackmail just about any rich person or corporation, by threatening to go back and destroy them. Therefore they would kill you. So you would have to go back and destroy them to protect yourself.

You would end up offering the time machine to people who would disappear the moment they gained knowledge of it.

Better to keep it to yourself and your pals.

Because the time machine isn’t invented until after humans are socially evolved enough to refrain from using it for evil.

You’re assuming that time travel isn’t regulated (actually it is, and in a very detailled way), and that time-travellers are interested in making money (actually, you’d better compare them with archeologists. They don’t dig up graves to sell the precious items they found).
You’re also assuming that they money they would gain would be of any use to them (who would want those 300 years old greenbacks? Not even a collector, since they’re extremely common and can be faked extremely easily anyway) or that at least they could use them to buy something which is valuable and easily available in the past (and there’s no case I can think of where both conditions are fulfilled).
You’re alqo assuming that time-travel is quite cheap, or at least cheap enough for some bets in the past to pay for the timetrip (and time-travel consumes a lot of ressources)

Finally, you’re assuming that bookmakers would be the better way to make money (or more exactly to make money to buy something the time-traveller could bring back). But there would be much more efficient ways to do so. For instance, stealing all the gold in the federal reserve with the help of modern technology if gold were valuable, or going back say 20 000 years ago and dig up the south-african diamond mines if diamonds were valuable.

This biggest flaw I see in this thinking is that the $$$ you would win as you went further and further back would become more and more worthless and that a BIG BET today couldn’t possibly be covered a few decades back, e.g. :

If you wanted to bet on the 1919 World Series (The Black Sox Scandal — when $100,000 split eight ways, was enough to convince 8 MLB players to throw the series) …

Abe Rothstein the gambler behind the fix bet $270,000 which dramatically dropped the odds and eventually led to the lid being blown off the whole thing. 270K on a **WORLD SERIES **is all it took circa 80 years ago to radically screw stuff up. Imagine you trying to win $1 Million in 1919. Not to mention if you showed up at your bank with several $100K worth of 1919 currency …I guess the bank would honor it, but am not sure … at some point tho they wouldn’t, e.g. $270K worth of Union greenbacks?

Whatever, bottomline the flaw is : A. you couldn’t keep going back because of the currency and B. the further you went back the harder it would become to get someone to cover big action.

Another way to make money would be to just go way back in time and place a small deposit into a bank which you know still operates in your own time.

You could then use the money earned to fund your time traveling project. :slight_smile:

Do you realize that $270,000 diversified across the stock market in 1919 would be worth several hundred million today?

Oh, I forgot, if you were around to pull in and out at key points (1929…etc), then it would be worth considerably more than that. I don’t think it would be a stretch to say billions.

How about going back far enough, emptying the Federal Reserve of its stocks of gold (or as much as you could carry), going back further and then buying property? Go back far enough, and you could probably buy up the land on which Central Park rests today. Or even Manhattan island!!

Of course, then you would have to hide your investment from successive descendants who would want to sell it off before you get to enjoy it!!

So, what if I go back in time seven hundred yeas ago, right where I am now. I take back a package of sewing needles, a couple of good steel knives, and some real nice warm clothes. I trade them to the Indians who lived here back then, and then go bury the stuff I traded for in the spot that will be my own back yard now in the twenty first century. I get the Indians to build me a burial mound over it, and tell them I am going to go to the great beyond, so just leave me here alone.

I can sell precomumbian artifacts! I don’t have any trouble finding the stuff, and it is entirely genuine and not even illegal by any stretch of the imagination. If I like the way that turned out, I find the oldest currently operating secure storage facility in the world, go back in time with some synthetic rubies of medium size to the date when it was first opened. I sell the rubies, and buy cheap stuff, store them then with prepayment, and instructions to surrender the trunks in which I stored them to the bearer of a letter identical to the one I leave with the management. Inner and outer elements of the letter prevent false claimants. If the first two don’t work, I go back, claim it a year later, and use three envelopes, etcetera. I open it up this year, and I have copies of the newspapers announcing the American Revolution, some of Thomas Pane’s pamphlets, Original copies of “Poor Richard’s Almanac” and a first edition of “Leatherstocking Tales” to sell. I even have letters of provenance from the storage place. I include a map to the “buried treasure” I already dug up, and have evidence of how I was able to find it. Then I go back and create a similar provenance for the letter, leaving it in a desk I buy and give to my grandfather.

Of course, in my case I have to kill my sisters to get the desk, but that is a different problem.


Any of you guys know what time it is?

I do realize that. Your suggestion, or others listed here, would be an excellent way to preserve the wealth, if it could be worked out. Your way would be difficult presumably with multiple “yous” apperaing decades apart and “proving” you had title to the stocks and maipulating them. Worth it, but I just didn’t go there.

But do you realize if you are going to maker the effort you don’t need to limit it to stocks? If you are in for a penny, Why not just build a diversified portfolio with stocks, bonds and commodities or anything you know will do well (like property or a busines) and retrun every decade and get in and out of stuff. Billions easily.

Nothing bad has happened because time travel hasn’t been invented yet, sheesh…