Start Learning Cosmological Math Today

[narrator]

Hi all..

As my appetite grows, so does the knowledge of my lack of knowledge.. lol

30 years ago as an engineering student I picked up calculus quicker than I did the more simpler math. I think that has to do with it being far more interesting. Mind you, with a side-step in career, I haven't used it in a long time.

Is there like an idiot's guide to getting started in understanding equations used in cosmology? I've read quite a few here and while some of it makes sense, a lot doesn't, like when using a' and a" etc. A list of conventions for variables would also be helpful. And I gather an understanding of the history attached to some equations goes a long way to understanding why they work - a big ask?

Thanks

 

[WannabeNewton]

Just a quick question: do you happen to know any General Relativity or differential geometry (because much of general cosmology is explained through the framework of GR)? If I am reading your post correctly then things like a' and a'' refer to derivatives of the scale factor from the Robertson - Walker metric (one successful way of modeling the universe) which is again part of GR. I think the starting point really depends on how much of a mathematical understanding you want of general cosmology.

 

[narrator]

Just a quick question: do you happen to know any General Relativity or differential geometry (because much of general cosmology is explained through the framework of GR)? If I am reading your post correctly then things like a' and a'' refer to derivatives of the scale factor from the Robertson - Walker metric (one successful way of modeling the universe) which is again part of GR. I think the starting point really depends on how much of a mathematical understanding you want of general cosmology.

My understanding of GR comes from documentaries and a little further reading, all of which I soak up like a sponge. As for "differential" geometry, I can only guess at the term from my rusty understanding of general calculus and how that may apply to spacetime geometry, as well as perhaps the referencing of objects, vectors and motion from different viewpoints - assumptions I guess.

As for how much I want.. hehe.. if I had my time over, I'd have done cosmology straight from high school. For now though, I'd like to gain some perspective on the math and then go from there. I quickly understand principles when they're explained, but fall behind in understanding how the mathematics proves them. It's like knowing that water is wet but never being able to feel that wetness.

 

[Nabeshin]

Learning GR is great and if you intend to learn cosmology with moderate degree of seriousness, then I would also recommend just picking up a book like Hartle's Gravity, which has a few nice chapters about cosmology within the context of GR.

If you're more interested in an astronomical overview of cosmology, and willing to take the GR a bit on faith, then perhaps a book like Ryden's Introduction to Cosmology would be better (prerequisites only calculus) [Also, I don't know if there are better books out there for this approach to cosmology, this is just the one I used for a class and I liked it]. Ryden goes through a lot of effects like big bang nucleosynthesis, inflation, formation of the CMB, which won't be covered in GR. That said often times I feel like the book is dealing with advanced subjects without thoroughly developing the background for them (for example, using the FRW metric by just saying "this is what it is"). It can be annoying, having to often just take things on faith, though.

 

[narrator]

Thanks Nabeshin.. those are both the kind of reading I'd like.

I might start with Hartle's Gravity.. sounds like a good intro.

 

[yenchin]

Thanks Nabeshin.. those are both the kind of reading I'd like.

I might start with Hartle's Gravity.. sounds like a good intro.

A nice thin book which is also quite readable in Andrew Liddle's "An Introduction to Modern Cosmology"

 

[narrator]

A nice thin book which is also quite readable in Andrew Liddle's "An Introduction to Modern Cosmology"

Cool.. I'll look that one up too.. Thanks!

 

[edgepflow]

A nice thin book which is also quite readable in Andrew Liddle's "An Introduction to Modern Cosmology"

I second this. This is an excellent and very readable book on Cosmology which presents calculations based on the Friedmann equation but does not require a knowledge of GR. After you learn this book, learning GR will be for meaningful.

 

[narrator]

I second this. This is an excellent and very readable book on Cosmology which presents calculations based on the Friedmann equation but does not require a knowledge of GR. After you learn this book, learning GR will be for meaningful.

Thanks edge.. first on my shopping list :)