system
Given the following post, respond as if you're commenting on Reddit:
human
Opportunities after completing physics PhD in your 40s

I think I've read nearly every post about starting towards a PhD later in life, but haven't found my particular questions answered.

**My questions are**:

- What paths are possible to move from a lower ranked school in undergrad to a higher ranked school for a grad program?

- If you finish a PhD in your mid-40s, can you expect to be able to work with interesting research organizations, such as NASA, Fermilab, US Antarctic Program, CERN, JAXA, etc? Especially if you complete your PhD in a non-Top-20 university?


**Context (to get a jump on the most common questions asked of OP I see in these types of threads)**:

- I'm 33, planning to go back to undergrad in about 2 years to finish a BS in physics & math (I'll likely take the full 4 years, just to be thorough) and, ideally, move on to a PhD with a goal of working in public research.
- US citizen living in California (but with residency in New York), but have lived abroad long term and happy (eager is more like it, tbh) to do it again.
- My wife and I have no children, and will never have children.
- My wife and I are comfortable with the lifestyle we can expect with me as a 40-something student.
- The tedium/politics/long-hours/etc of academics doesn't faze me.
- My current career is virtually non-existent, and has no relation to STEM.
- I have no interest in using my current skills to go into a field tangential to research, like science journalism, science policy, etc
- I've checked my math skills and they're the same as always—definitely above average, but not brilliant (and I've worked out a 2 year plan to improve these skills).
- As for where I'm likely to get accepted for my undergrad, I don't expect to be able to go to a Top-20. Maybe a Top-50?

Yes, I have the deep passion to pursue this, but I also don't want to end up >$150k in debt only to discover at the end of things that I won't be able to actually go beyond the degree in a way that's meaningful to me. That said, I have no illusions about working on the next world-changing thing. I just want to at least be some cog in the public science machine.
gpt
Is your goal to become a researcher with a permanent position at a university or national research lab? The prospects for this are poor for someone who does their PhD in their 20s, and much worse for you.