I would like to ask you all a question about Photons and the expansion of the universe, and how they relate to one another. I thought about it after a long talk with a friend about how photons react to the universe, and how they basically don't experience time, since they are in fact traveling at the speed of light, where the time dilation is close to infinite. Then I wondered about what exactly happened after the big bang? We have the microwave background radiation that we can observe, and red shift and blue shifting of bodies of light traveling towards and away from us, that I understand, but, here's the question that got me waking up at 5 in the morning: where exactly does the energy of the photons that are stretched out... go? X-rays and Gamma rays are more powerful than radio waves, right? So if the big bang was a bright expansion of gamma rays, where does that energy go when it is stretched out? It doesn't exactly make sense to me. Then the thought came to me, is light traveling through space what causes the universe to expand at the expense of the energy they lose? Does the light lose energy as a result of space-time expanding, or does space time expand due to the force of photons? (Is photons losing energy during their travel through space actually the answer to dark energy?) I am looking forewards to your responces, and if you may debunk my idea or explain why it doesn't work, for some reason I do not yet know, please do so. Thank you so much for your time!