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I can't recall how long ago I read this book, but it starts with 2 college kids using some form of wormhole or instant travel mechanism they invented to personally witness man's first landing on Mars. The story skips then to them being ultra rich & nigh-immortal due to medical advances. One lives on a hollow asteroid that is very well appointed, the other more in touch with the world & politics. The story is somewhat light with a bit of mystery & discussion of societal impacts from income discrepancy.
All my recollection of important events in the book are vague.