Before I ask my questions I need some context. Here are two quotes about electroweak unification: from (1) https://en.wikipedia.org/wiki/Electroweak_interaction , and (2) from https://en.wikipedia.org/wiki/Fundamental_interaction . (1) Mathematically, the unification is accomplished under an SU(2) × U(1) gauge group. The corresponding gauge bosons are the three W bosons of weak isospin from SU(2) (W+, W0, and W−), and the B0 boson of weak hypercharge from U(1), respectively, all of which are massless. In the Standard Model, the W± and Z0 bosons, and the photon, are produced by the spontaneous symmetry breaking of the electroweak symmetry from SU(2) × U(1)Y to U(1)em, caused by the Higgs mechanism. (2) Electromagnetism and weak interaction appear to be very different at everyday low energies. They can be modeled using two different theories. However, above unification energy, on the order of 100 GeV, they would merge into a single electroweak force. Electroweak theory is very important for modern cosmology, particularly on how the universe evolved. This is because shortly after the Big Bang, the temperature was approximately above 10^15 K. Electromagnetic force and weak force were merged into a combined electroweak force. I assume that (2) implies that when the average of the mass-energy of particles had an average value of 100 GeV, their temperature was about 1015 K. Q1. Is the above assumption correct? I do not have the skills to calculate this, so I am hopeful someone will supply an answer for me. Q2. What is an approximate value of the scale factor a (currently a = 1 exactly) and time t (currently t = 13.8 Gy approx) corresponding to 1015 K? Since wikipedia gives conflicting information about the timing of inflation and unification, I am making the following guesses: a) Electroweak unification occurs at a lower temperature than it's Grand Unification with the strong force. Therefore, electroweak de-unification occurred later than de-unification with the strong force. b) In particular, de-unification with the strong force began when inflation started, and electroweak de-unification ended when inflation ended. c) The time corresponding to the temperature 1015 K was when electroweak de-unification started.Q3. Are my guesses (a), (b), and (c) likely to be approximately OK? Let ts represent the time when electroweak de-unification started. and te represent the time when electroweak de-unification ended. Some questions based on my interpretation of (1) Q4. The bosons W+ and W- existed since the end of the Planck epoch. Is that correct? Q5. Before time ts the Z bosons do not exist, and they do exist after te. Is that correct? Q6. Before time ts there are no photons. Is that correct? If that is correct, does this mean there is no electrostatic force between charged particles? Or, is this force is carried by a different particle, perhaps B0? I expect to have some additional questions after getting some answers.