Frederic

Thank you for your answer!

Sorry this is a problem of linguistic (I am french and translating myself to English). By "Planck's limit" (which is how we call it in french), I mean the lengh of Planck, or the energy of Planck (10*-35 metres or 10*19 Gev). My question is about how much time after this limit (which is abstractely proposed to be 10*-43 seconds after a very hypothetical singularity that only works for simple relativity) have our theories been experimentally verified ? Considering that when we collide particles having a X amount of energy, we experimentally recreate conditions that existed when particles had this X energy in the history of the universe, our equations have been verified until this X particle energy time. Between this X energy time and Planck's time, we only have unverified equations (and before Planck's time we have no equations). My question is what is the maximum energy that we have given particles in accelerators, and how much time after this "Planck limit" is this energy level ? (I know that so far the collisions have always verified our equations, but that we are still very far from 10*19 Gev) EDIT: Ok, I have found a partial answer on the LHC website. Particles so far have been given a maximum energy of 6,5Tev, giving the collision a maximum energy of 13Tev. The rest of my question is how much time after Plancks energy (10*19Gev) is 13Tev in the history of the universe, and is this before the appearance of the cosmic radiation background ? Let me try to state this in an other way. If the time of the hypothetical Big-Bang singularity is 0. Planck's time when particles had a 10*19Gev energy would be 10*-43 seconds. And the cosmic radiation background would be 380'000 years. What would be the time when particles had 13Tev energy ?

From what I understood, our theories (relativity and quantum) enable us to trace our history up to Planck's limit. Beyond (before) that point, our cosmology remains a mystery until the Fundamental interactions are unified in a single formalism (because the space-time decribed by relativity and quantum physics are incompatible). But our equations after Plancks limit are only verified up to a certain energy level of particles (with the LHC and other accelerators). My question is, where in time (or in energy level) does this point lie ? And is the cosmological background (the point where photons becomes free about 380'000 years after Planck's limit) before or after this point of verified knowledge ? Another way to ask the question would be, at what maximum particule energy level have we verified our equations in accelerators, and to what time does this energy level correpond ? Thank you ever so much for your simple answers ! EDIT: Ok, I have found a partial answer on the LHC website. Particles so far have been given a maximum energy of 6,5Tev, giving the collision a maximum energy of 13Tev. The rest of my question is how much time after Plancks energy (10*19Gev) is 13Tev in the history of the universe, and is this before the appearance of the cosmic radiation background ? Let me try to state this in an other way. If the time of the hypothetical Big-Bang singularity is 0. Planck's time when particles had a 10*19Gev energy would be 10*-43 seconds. And the cosmic radiation background would be 380'000 years. What would be the time when particles had 13Tev energy ?