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Who or what is Alpha,& how does his/her/its response follow from what I wrote? I cannot parse the response. Please translate it into something readable.I think I may have offended you with my unseemly lunchtime haste, David.
For some reason Brian stripped the ^ symbols from my version of the Friedmann equation, which ought to have been copied above as:
x*(dx/dt)^2/H_0^2 = [Omega]_m + (1 - [Omega]_m - [Omega]_lambda)*x + [Omega]_lambda*x^3 .
Brian's comment suggests to me that maybe some readers may not understand my notation as far as reducing mathematical equations into an ASCII form.
So here is a dictionary of my notation:
* = multiply by.
/ = divide by.
+ = add to.
- = subtract from (when a binary operation) or negate (when a unary operation).
^ = raised to the power of (i.e. what immediately follows is a right side superscript on what immediately preceeds the symbol).
_ = lower right susbscript (what immediately follows is a right side subscript on what immediately preceeds the symbol).
[greek letter] = the corresponding symbol for the greek letter named in [...], (e.g. [Omega] = capital letter omega, [pi] = lower case letter pi).
dx/dt = the derivative of x with respect to t.
(...) = parentheses indicating a pending operation is to be performed on the whole evaluated value of of whatever expression ... is inside them.
^ and _ symbols take precedence over * and / symbols which, themselves, take precedence over + and - symbols.
BTW, when raising a subscripted quantity to a power the whole quantity is raised to the power, not just the subscript. So in the above Friedmann equation H_0^2 = (H_0)^2 = the square of the Hubble parameter, H_0, rather than an H with a subscript which is the square of zero.
So could Brian please translate Alpha's response into a notation compatible with the above scheme?
Thanks.
David Bowman