How to Profit off Time Travel?

Let’s say you’re the late-21st-century government of India, and you have access to time travel.

It works like a train. You create a permanent wormhole back to a particular point in the past, then lay rails through it. Traffic can now flow in both directions. Changing the past does not change your present. It’s as if you opened a rail line to a foreign (and technological primitive) country.

So how can you make money off of this?

1. Patent and sell future technology to the past. You could also engage in some social engineering by deciding which tech to release.

2. Selling short during crashes. You arrive right before a crash, sell a lot of whatever (maybe shares in TimeTravel Inc or bonds in future governments?), and then buy it all back after the crash. What would the effect be on the past economy? It would balance out the crash, right, with the injection of cash from the future? The future people could say they were doing the past people a favor.

3. Profiting from bubbles. Okay! So the future people arrive at the height of a bubble and sell a lot of whatever is currently inflated (silver, houses, tulips, whatever). That inflates the bubble more, and the crash comes later and is bigger than in canonical history. As Stephen says, this sort of insider trading will distort the hell out of the local (past) economy. But what do people in the future care about that? They sold a lot of tulips!

4. Commodities trade. Use future-tech to manufacture petroleum or diamonds or whatever and sell it to the past for cash, which you can use to buy resources that are more precious in the future (say, rare earths…or CHILDREN?? Dun dun dun!). Of course, flooding the past-market with commodities will cause a crash in their price, probably inflating their currency into uselessness, but that’s a good thing. It’ll make those past-jerks dependent on the future-people for their money supply. (think the Spanish fleet dumping cowrie shells on the Pacific Island market and destroying them as a currency).

5. Fix problems. Yes. In addition to illegal or semi-legal vigilantes going back in time to kill historical villains (Hitler keeps getting assassinated), future governments topple regimes like the Nazis and the Maoists or prevent them from forming (several 1920s European countries get partitioned, so do 1950s China and USSR, the 1980s Arab world gets lots of irrigation technology, etc.). The future people say they’re preventing terrible evil, but the people who replace the Stalins and Pol Pots are always suspiciously meek and obedient to the future, and it’s hard to see any improvement to the lives of normal people. Think the Cold-War juggling of African and Latin American dictators.

6. Treasure-hunting. You think the future is going to leave priceless relics just lying around for past-living barbarians to play with? That stuff belongs in a museum! In 2139! And if you think any of you barbarians are getting access to the Amber Room or the Buddhas of Bahmiyan, or the Amazon Rain forest, forget it. (also, you can go out and recover the wrecks of the Atocha and the Black Swan for a cool $1 billion)

And yes, you can travel to the past, start a new timeline there, build a time machine in that timeline, and start your own money-making scheme in the past-of-the-past. In fact, in order to pay their debts to the future, the past-people sort of have to make their own time machine. It’s like a pyramid scheme and space-race and globalization rolled into one!

But I feel like I am missing something. Any OTHER ways to profit from time travel? Assume that I am evil.