You won't find any professor in the biology, physics, chemistry - or even religion - departments who would claim that the earth was actually created in six days.
If you assume for the sake of argument that Genesis was written by a divine being, then it should be obvious that He is describing a process beyond our understanding then and slightly less beyond our understanding now. Further, He would be describing what *He thinks* is important about the process rather than what we can plainly see from the inside. Many people have tried mutating the literal account to make it work, including the whole 1 day as a 1,000 years thing, but it does not work. It is quite possible, however, for it to both be literal and easily reconciled with science: it's just a production sketch.
If I write a program, the time it took me to write the program has no relation to its run time. If I shoot a film, the time it took me to film has no relation to the run time of the film. I can also write parts of the software or shoot sequences of the film in whatever order is convenient, regardless of how it actually plays out. I can do the dialogue on the first day, the action sequence on the second day, then go back and film the opening sequence. When I do the opening sequence, which covers the billions of years before the beginning of the story of interest, it fills about twenty seconds of reel time. Similarly, when stars spring into existence in the creation account, so does light already millions of years in transit and all of the laws which guide their motion. That's more or less how I tend to look at it.
We tend to create the divine in our own image, forgetting that we are linear and He likely is not. YHWH presumably created what we experience as time itself and lines of history, perhaps even multiple lines of history, all at once and that is not easy for us to envision. So, given the assumption that the account is divine, then it becomes a matter of why the divine gave us that account and what He thought we should take away from it. Certainly not the age of the universe or the behavior of galaxies--- as that is something we can see for ourselves. Rather that He spoke the world into existence, the categories of things he felt were important to the [our] story, and that we were given a specific task in that story: tend My garden, be steward over and name the beasts, the origin and importance of the sabbath (both the weekly cycle for people and the seven-year cycle for fallowing land). We're absentee landlords and beholden to our boss when we do it badly. He gave us some instructions for how to go about the task. At some point (from our linear point of view) He is going to check on our performance and we know that the owner's son is willing to intervene on our behalf to reduce the punishment due for much of our idiocy. That's really what scripture is about. The rest is gravy.
I therefore don't tend to bother too much about the exact age of the earth or other details. It's interesting to speculate about, the science can be fascinating, but it is not directly relevant to my task--- one way or the other--- so it just isn't that critically important. We can never prove history one way or another since, for non-divine beings, history is not an experimental science.
If you don't buy the assumption--- that Bereshet/Genesis is of divine origin--- then I can't help you on that much. That's a very different argument.