LOL

[conuly]

http://www.sheldoncomics.com/archive/130916.html

So, my mother and I were talking about time travel. Her big plan with time travel is to go back in time, exchange modern bills for older series bills, and do her groceries on the cheap. Which, quite aside from being the very definition of a mundane utility, has a few practical problems with it.

Lets take a shopping trip in 1980. She obtains $100 in $20s from the 1980 series. It's not clear if she's doing this exchanging now or in the past, but I think making the exchange now creates fewer logistical difficulties, though the end result will be the same.

She goes back in time and does her shopping, using those bills. But those bills already exist! With every trip, she is devaluing the money by adding 5 new 20s to the mix. Worse, if she continues this shopping, sooner or later those bills are going to meet! It'll be a paradox to beat all paradoxes. The world will explode! And why?

Because my mom wanted to pay less for coffee.

Comments

[steorra]

I don't understand how swapping old and new bills will let you get groceries for cheap.

[conuly]

You swap for face value today. Due to inflation, that means that when you go back in time your money is worth more. If I go back to 1980, every $20 bill will buy as much as $56.77 would today. That's a lot of savings! I might need only $45 to do the shopping that takes me $130 nowadays.

But you can't spend bills from the 2000 series in 1980. They don't look the same.

[conuly]

Of course, what my mother is forgetting is that some things are easier to obtain now than then. When I was a kid, stores stocked at most three kinds of apple. Now, even the crappiest supermarket will stock at least five. So you might not be able to do all your shopping in the past.

[houseboatonstyx.livejournal.com]

There WAS a story like that, probably in the 1950s! don't remember how they got money that would pass, but an elderly couple got some sort of gate that let them go back to the Depression to do their weekly grocery shopping, and lived happily ever after. Which was the end of that story, after mid-story 'conflict' about their poverty and who invented the gate and how they got it.

Your ideas could be a sequel to that story.

As for the bills meeting and exploding, what if the buyers are in our future and coming back to 2013 to buy at our prices, using not physical money but 1s and 0s stored in some computers. Granted doing that hack might be more work than collecting old paper money.

[elenbarathi.livejournal.com]

I remember that story - the old lady going to the butcher shop, loading up on steaks and roasts for pennies. Don't remember how the money/paradox issues got worked out - time travel was a new technology back then.

[houseboatonstyx.livejournal.com]

I don't think the old story even looked at those issues. It was just 'here's this important discovery and all it gets used for is one little -- but happy -- result'.

There was a similar story about creating objects by some sort of field replicator -- but the objects only lasted a short time, and iirc only within range of the replicator. So the -- happy -- ending was, it got used only by some nice elderly couple to make free appetizer rolls to satisfy their restaurant customers. They charged only for the real food.

[elenbarathi.livejournal.com]

What a weight-loss plan that could be! ^^

[elenbarathi.livejournal.com]

If she's got a time machine, she'd do better to go back and rescue a bunch of incredibly valuable antiquities that have been lost to history. For sure, kipe as many documents as possible from the Library of Alexandria the night before the fire - leave them to age in some safe place, such as a cave in the Mojave in 500 BCE; retrieve them when they're the proper age, then go back 200 years or so, buy some steamer trunks and age them. (Of course all this aging of stuff for centuries is a matter of moments for someone with a time machine.) Put the ancient documents in the antique trunks and hide them in some plausible place where you can 'discover' them with no possible dispute to your claim of ownership.

What it would look like would be that some unknown, long-dead person had found and hidden these documents before, say, WWI, when all kinds of valuable antiquities went missing. Sheesh, go on a burglary spree in Dresden, the night before the firebombing - all those people are going to die anyway, and all their stuff be destroyed. In fact, with a time machine, one could go rob Dresden the night before the bombing as many times as one wanted, and make whatever arrangements one wanted in order to legitimately inherit everything in due course of time, with all the proper documentation.

... artifacts from Peking, the night before Genghis Khan sacked it. Artifacts from Troy, Carthage, Babylon, Chichin Itzil... all those mighty, vanished cities of the ancient world, all that wonderful stuff that disappeared and was never found... granted, the atoms of the elements comprising all those items would be taken from one time to another, so there would still be a great big paradox: a gap of however-many years during which those atoms didn't exist.

Therefore, it might be best not to try to transport material objects from one time to another at all, and instead only go to gather information about what is where, and/or hide things in safe places in their own time, where one will be able to retrieve them in one's own time. For that matter, one could go back in time and move them if necessary - if ever one found them missing, one could go back to before they were missing and move them somewhere else. The only caveat would be to only hide items that one knew to be subsequently destroyed, or that were never found up to one's own time, so as not to interfere with human history.

As you know, the Vulcan Science Academy has determined that time travel is not fair. ("Thanks, Captain Obvious!") With this in mind, the odds are very much in favor of something going disastrously wrong no matter how one tries to work it. Probably safer to just drink less coffee.

[houseboatonstyx.livejournal.com]

Well, the writers of the Star Trek reboot didn't bother to use it to abort the destruction of certain planets -- or to cut the part of the script that said it had been so used.

[conuly]

There's a series of books where future people did that with babies, saving kids who had historically died and bringing them to the future as orphans. For some reason they always de-aged in the process.

[marveen.livejournal.com]

That's the kind of thing I always thought of.

IIRC, Christopher Stasheff used a similar device in one of his books--people buried things like a child's toy doll in BC and dug it up in like the '60s, when museums and collectors were paying lots of money for such things.

My own get-rich-quick plan with time travel involved aluminum ingots and gold coins. (Take aluminum back to before it was cheap, convert to dollars, convert to gold.)

But the "lost" knowledge--how did they make Chartres Blue? What was the process for the micro-granulated gold pieces from Rome that we STILL can't duplicate? Stonehenge, Nazca, so much to go and FIND OUT--