Recent content by romeo6

Yes. I've taken some grad math also.

This is a great answer (along with others). Actually, I've started thinking about it in terms of orthogonal basis. Would you're base vectors not have to be orthogonal to take a derivative with respect to something else? If you started taking derivatives wrt a basis that was some...

I've taken plenty of calculus (believe it or not), it's been a few years now though, and I've not used it for a while.

I certainly wasn't ignoring you, however I found your next post valuable, with the example of taking the derivative of x^2 wrt e^x.

You're right - just intuition. Which is probably failing me.

But if f is a function for (x,y,z) and g is a function of (x,y,z) then surely that's possible. Probably I'm wrong if I have to ask about it.

Is that not possible?

If I have two functions, f(x,y,z) and g(x,y,z), do I use the chain rule to calculate df/dg? e.g. df/dg=df/dx df/dy df/dz Cheers! Romeo

...anyone?

It's this paper: http://arxiv.org/PS_cache/hep-ph/pdf/0301/0301168v4.pdf equation 1.

Hi Mute - I think I was modifying the expression while you were kindly looking at it. This one's good.

Hey folks! I'm trying to figure out an identity from a paper on dimensional regularization. Here's the identity: -\frac{1}{2}\frac{d}{ds}|_{s=0}\int_0^\infty \frac{d^4k}{(2\pi)^4}(k^2+m^2)^{-s} after performing the k-integral this becomes...

Thanks for all who responded to this topic for providing your insights. I'm very interested in seeing what would be most cost effective. Spending $100 Billion + on a lunar mining program, or spending $100 Billion on an Earth based program to generate the He3 artifically with, perhaps, an...

Ok, I see - thanks for putting me straight on the Petawatt aspect. So here's another question. The whole purpose of mining He-3 would be for a more energetic fusion reaction so one would assume that fusion technology would have been pretty much perfected before we started performing any...

Thanks for the quick responses mgp phys and Astronuc. It sounds like there's nothing physically wrong then with the idea of creating He-3 here on Earth instead of launching massive mining operations and sending them to the moon. Astronuc - what do you think of the idea of using PetaWatt...