Recent content by xortdsc

Ah, so "sqrt(1-rs/r)" is simultaneously the time dilation ratio and space curvature ratio at distance r. Do I interpret this correctly ?

Hello, given a stationary pointlike particle with mass m at some position, I'm trying to compute just how much space is curved/deformed at a distance r from that particle due to its gravitational field. I'm not really into all that tensor calculus, so I really struggle with the equations given...

I figured it out. So to answer my own question: High restitution happens if the internal links are very stiff compared to the stiffness of the collision. Restitution appears to depend solely on the ratio k_internal/k_collision. The remainder of the energy, if restitution is less then one, goes...

Hello, just for some basic understanding I wrote a (1D) numerical simulation to investigate the internal mechanics of collision impact in different materials. For a start I work with a really simple model which consists of: - basic elements (circles of fixed radius and mass and their current...

okay that would make sense. so it really is the case that as they approach, mass energy goes down and kinetic energy goes up by equal amounts (so rest mass is converted to kinetic energy) ? Upon annihilation mass would become zero and all energy is stored as kinetic energy which then radiates...

if by "classical concepts" you mean position and momentum, how can any theory get rid of these ? Sure they are only approximations as in reality there are fluctuations all over the place. So what I mean by terms like position/momentum would be rather an average (to smooth the noise present)...

and the argument... "it is 2 times the (invariant) rest-mass of the electron, but if mass is invariant, where does the kinetic energy come from ?" ...does not raise any fundamental questions in you ? and again, I'm aware that classical physics will not be sufficient and the "bug" is in the...

mass is either constant (invariant mass) or increases with kinetic energy (relativistic mass) check this article: http://hepth.hanyang.ac.kr/~sjs/physics/mass.html so how could it possibly pay the kinetic energy toll with its mass ? It makes no sense. most people here don't seem to...

well, just because it was beyond my knowledge i was asking this question in the first place ;) is there nobody that has derived a modified coulomb law from quantum field theory to work out the energy involved at a certain separation in relation to vacuum energy ? i can not start with a small...

so you also have to add that potential energy it to the mass energy when the reference point is the vacuum energy. well, the energy drops below zero once the coulomb potential becomes smaller than -2mc^2 which it will below a certain distance. yes exactly, I'm aware that you can not use...

yes, that's right. i meant vacuum. i said nothing as vacuum after all is as much nothing as it physically gets in our known universe. ;) so if you are saying that it only needs +2mc^2 of energy relative to the vacuum energy to create the pair and separate them to infinity, then where does the...

I'm asking the same question, because the answers don't seem to fit. When you are saying that the initial energy is 2mc^2 + V(x), where V(x) = -e^2/x i can totally follow that. And sure you're right that by conservation of energy it still is on that level after they annihilated (possibly as...

I could turn the question around and ask: "Given an electron and a positron at rest separated by x meters, how much energy would they release upon annihilation ?"

the problem is that this won't help me to find out how much energy actually went into creating the particle pair which subsequently depart to infinity. sure i can assume the initial separation to be small, but whatever distance i choose i will get different energies (the smaller the initial...

yes, that's what i thought. but how much potential (coulomb) energy does it have ? that was my initial question just with a different formulation. the normal coulomb potential is insufficient as it would suggest that you can not even slightly separate two superimposed electron/positron without...