Recent content by physicsforumsfan

[Moderator: link removed] Can a jet engine the size of the tunnel mean that you can have an effectively have drag-free vehicle? Any lorry tethered to the jet engine would be basically be drag free? Is this correct? Thanks

Hi, Reading about different ways to lift a human being, I've come to realize the easiest is simply manipulating density as follows: Denisty of Air at STP: 1.20 kg/m^3 Density of He at STP: 0.000179 kg/m^3 Therefore for every cubic metre (m^3) of air displacement, lift achieved is ~1.2 kg/m^3...

Hi, Thank you for replying (hilbert and vanhees!). I cross multiply the matrix, factor in the fact that E=pc to get: γP * matrix [ 1, -v/c] [-v/c, 1 ] How do I solve this?

Homework Statement The question is quite basic; what is the Lorentz transformation of the follows 4-vectors from S to S' frame: A photon (P) in S frame with 4-momentum P = (E/c,p,0,0) and frequency f where hf = pc = E. h is the planks constant, p is the magnitude of 3-momentum...

Hi, I just noticed by assumption which as you said, is incorrect. I am using the gamma factor because I know the answer involved is P multiplied by a form/shape of the gamma factor (ie. sqrt (1-(v/c)^2)).

No Help? Hey everyone, Seems like another thread with no actual replies. Just so I know, were the questions too hard or were they difficult to understand because of how I wrote them? I would like your honest opinion. Thank you

Hi vela, Thanks for replying. The lorentz boost (or the transformation) of any four vector is the lorentz matrix multiplied by the vector according the the article http://en.wikipedia.org/wiki/Lorentz_transformation#Transformation_of_other_physical_quantities. Essentially, the article is...

Hi, Looks like no reply, must be difficult questions... Anyways, I just like to added that for part two: \overline{P}=γP where P (NOT dashed) is the 4 momentum for frame S. Now if anyone can agree with me on this, easier to read, equation. Now for Part 3... Anyone?

Right so in 3, P violates which in turn violates C and that's my original conclusion?

Right Mark, thanks for telling me. Just to clarify my questions, here is what I am trying to ask. In Part A - I am supposed to find the transformation of the L matrix using that tensor equation. Is my transformation correct? It was my attempt at the question. In Part B - Again, are the...

In Part A - I am supposed to find the transformation of the L matrix using that tensor equation. Is my transformation correct? It was my attempt at the question. In Part B - Again, are the components of \overline{S} correct (ie. is \overline{A} correct)? It was my attempt at the question...

Invariant means it has not changed state (ie. X->X and not X->Y). If P is 1 (inverting=violating) the result changes X->Y without C changing to 1 (C=0, P=1, X->Y) then how can we say C will always violate (invert) when P does? Isn't that what my original conclusion says? I am probably missing...

Hi haruspex, Thanks for the table and explanation. I am still unsure of the conclusion. Violating P violates C (when T is not violated) is the answer i gave but in the table it says 1 1 0 X for C, P, and no T violations, respectively. Since the system is left invariant, C is not...

Hi, no reply? Help?

Hi, no reply? Help?