Author's Note: This is my first fic, hopefully I don't screw it up too badly. This story is highly AU from canon as you shall soon see. Oh, and I don't own Mass Effect either. I also don't own Space X or General Fusion, which are, by the way, real companies. Lastly I'm stretching out the timeline a bit, humanity has about 500 years before 1st contact.
Chapter 1: point of divergence
2016a: Space X's dragon v2 capsule successfully brings crew to the international space station, as the craft is entirely reusable it is ready to go again in about an hour.
2016b: a small scale warp test reveals that they have in fact managed to produce miniscule distortions in space-time. The effect is however too small to be useful at the moment.
2017: General Fusion succeeds in developing magnetized target fusion for generating electricity, but due to the way it works it is unable to be used as a fusion torch engine.
2019: Space X has finally gotten people to SHUT UP about their use of nuclear thermal rockets for their new launch vehicle.
2020: The energy crisis is officially declared solved, though certain Middle Eastern countries are rapidly going into revolt as their income from fossil fuels dries up.
2026: Cybernetic prosthetics are developed which are actually better than the limbs they are replacing.
2024: Arabia needs to be invaded again to keep a massive civil war from breaking out.
2030: The 18 year long Syrian Bloodbath finally comes to an end when a random asteroid that the scientific community missed annihilates the entire country.
2034: Destiny, the first O'Neill cylinder is completed in the asteroid belt. It is an entirely self-sufficient city that later declares itself capitol of the newly formed Belt republic. As getting out there still takes about a month at best, this claim is uncontested.
2042: Purely magnetic confinement fusion is developed, allowing for the development of fusion torch engines, in-system travel times are reduced greatly.
2056: A breakthrough in AI research occurs entirely by accident as a new high-resolution brain scanner produces a real-time simulation of the subject's entire brain. Sadly, the new AI went insane due to the lack of any outside stimulus.
2060: Stellar Lifting technology is developed for the purposes of creating millions of habitats to ease the overpopulation on earth. It works by magnetically ripping plasma out of the sun, which actually makes it last longer. This plasma is converted to heavier elements through the usage of nuclear fusion.
2062: A gradual uploading process is developed that turns the subject into an AI over the course of a week. It works by slowly converting layers of brain tissue into a nanotech computing substrate running a partial brain simulation, which stimulates the remaining organic tissue as if the brain were still whole, and applies stimulus to the partial simulation in much the same way as the brain is slowly converted. This is to ensure continuity of consciousness (they want to make sure it's really the same person in there). This procedure becomes mandatory for all military personnel.
2063: In a bungled attempt to make the necessary exotic matter to run an Alcubierre 'warp drive' a different type of exotic matter is produced that was found to have an utterly absurd tensile strength, though it isn't rigid in the slightest. This enables the construction of megastructures similar to the one in Larry Niven's Ringworld books. Estimated time to completion is 300 years.
2067: Venus and Mercury are completely disassembled for raw materials. (This project had been going for about 30 years, but no-one really paid much attention to it before.)
2073: Advances in intelligence engineering increase the intelligence of all uploaded/AI citizens by an order of magnitude. The 1st singularity has occurred.
2078: The new trans-sapient population gets fed up with the constant 'stupidity' of the organic populace, and forcibly uploads them all.
2081: Industrial antimatter production becomes feasible, but is seen as a 'dead end' technology and ultimately ignored.
2084: A prototype Alcubierre warp drive is tested, though only capable of reaching 1.1 c, it's just a proof-of-concept, the technology obviously has room to improve.
2085: The Prothean ruins on Mars are discovered. The HDI (human derived intelligences) regard eezo as more of a hindrance than a resource, as they are already capable of producing exotic matter with negative mass to get their warp drives to work, and simulations show that relying on eezo would ultimately cripple their technological development, as apparently happened to the Protheans.
2086: The paranoia related to sharing the same fate as the Protheans leads to the ring plans being revised (it will now boast 200 km thick armor and allow the entire solar system to move at FTL speeds.) All the rocky planetoids in-system are used as raw materials (including Earth), dropping estimated time to completion to only 74 years.
2090: An interesting quirk of the Alcubierre warp drive is noted by the 1st extra-solar colonization fleet headed to the Alpha Centauri system. For reasons pertaining to warp torus scale and exotic matter generation rates, bigger ships apparently move faster. As the 5 km long light construction vessel can only move at a few lightyears an hour, while the 30 km heavy freighter is at least an order of magnitude faster. Extrapolating this reveals that a 'ringed' star system should be capable of intergalactic travel.
~BLAH BLAH, 2nd singularity, putting a ring in every HDI system, capable of churning out 1000 warships/hour/system, faster warp, time-skip to 1st contact with Turians, BLAH BLAH!~