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

[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! ^^