Peter4075
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 Apr 10 awarded Fanatic Mar 12 awarded Notable Question Feb 24 comment How were the solar masses and distance of the GW150914 merger event calculated from the signal? Shouldn't the term in square brackets be raised to the power of 3/5? Feb 20 comment Physical and non-physical solutions to Einstein's field equations Thanks for that. Feb 19 asked Physical and non-physical solutions to Einstein's field equations Feb 5 comment How far do we need to be removed from the earth to show the curvature with a viewing angle between 42 and 48 degrees? If I'm standing on a beach and hold up a straight edge to the horizon, surely I'll see the horizon falling away from the straight edge. Doesn't that demonstrate the curvature of the Earth? Jan 15 accepted Two ways of writing coordinate basis vectors confusion Jan 15 comment Two ways of writing coordinate basis vectors confusion Expressing basis vectors as partial derivative operators still looks weird to me, but you've answered my question. Thanks. Jan 15 comment Two ways of writing coordinate basis vectors confusion Sorry to be so slow, but do you mean my first equation can be written as $$\vec{e_{r}}=\frac{\partial}{\partial r}=\frac{\partial x}{\partial r}\frac{\partial}{\partial x}+\frac{\partial y}{\partial r}\frac{\partial}{\partial y}.$$ Jan 15 asked Two ways of writing coordinate basis vectors confusion Jan 10 comment why does the higgs mechanism need to exist? "Pleb" is a term senior Tory politicians in the UK may or may not use when asking police officers permission to cycle through the main gates at Downing Street. Possibly. Nov 26 accepted Galileo 5 and 6 satellites testing gravitational time dilation Nov 26 comment Galileo 5 and 6 satellites testing gravitational time dilation Excellent link. Thanks. Nov 26 asked Galileo 5 and 6 satellites testing gravitational time dilation Nov 11 comment Is partial derivative a vector or dual vector? Where does $\partial_{\mathbf v}f = \langle\mathbf df, \mathbf v \rangle$ come from? Is it a definition or can you derive it? In "Gravitation" it (Eqn 2.17) seems to be derived from some sort of Taylor Series (Eqn 2.15), but I've never seen this derivation in any other textbook. Usually $\partial_{\mathbf v}f = \langle\mathbf df, \mathbf v \rangle$ is just stated. Apologies if I'm missing the obvious. Nov 10 comment Time taken to cook frozen peas Must admit, I've never heard of cooking frozen peas without water. It works - I've just tried it - but you need to be careful, the saucepan gets very hot (my stainless steel saucepan began to discolour with the heat). Don't burn down the kitchen! Nov 10 accepted Time taken to cook frozen peas Nov 10 comment Time taken to cook frozen peas Thanks. I thought that would be the case but didn't have the physics to back it up. Nov 8 revised Time taken to cook frozen peas edited tags Nov 8 revised Time taken to cook frozen peas edited tags