creating whole new timeline. That being said, future from that point on would once again be unknown, and the possibility that bitcoin never gets traction it has today would be an option also.
Not to mention xy other paradoxes that scientist predict would happen.
Far better thing you could do is invest today, and prevent future self from creating same thread in the future, wishing you could travel back to 2015.
cheers young troll traveler
the butterfly effect
There is another theory which claims quite the contrary, that all your changes to the past (including your very presence in it apart from your proper timeline) will be undone eventually...
In this way, you can't essentially change the past, but can only be a negligible observer or looker-on