I am quite glad you did tell. I have never, that I know, heard of bubble universe, but one of my episodes was about a dream world in which the astro-physicist was dreaming about the universe being like a vast collection of soap foam bubbles. I didn't go into detail about it. Just a quick scene. Interesting.
Or no travel at all, beyond some particle that contains its own medium. That would mean, no force or energy can be added to the system, so all possible accelerations would cease, and whatever velocity was achieved, pre-bubble universe exit, would be maintained. No ftl travel. On the other hand, distance may have no meaning, so instantaneous traversing between bubbles, all bubbles.Could this lack of medium allow communication to travel faster that light?
Just a theory.
Light gets stretched as the universe expands - hence cosmic red shift. In the period t=10^-36 s to t=10^-32 s, what we can now observe of the universe expanded in size by a factor of 10^26 (10^78 in volume) from 8 x 10^-30 m across at t=10^-36s and was about 0.9mm (9x10^-4 m) across at t=10^-32 s - about the size of a grain of sand. However, this may have occurred during the electroweak epoch before any particles had mass. At about 10^-12 s, the Higgs field developed a vacuum expectation value and electroweak symmetry was spontaneously broken by tachyon condensation. W+ and W- bosons, Z0 bosons and fermions acquired mass and could no longer travel at c. Before this time, everything travelled at c. Photons did not exist as such as there was no electromagnetic field separate from the weak field. The equivalents of photons, W+ and W- bosons and Z0 bosons were bosons of weak hypercharge and weak hyperspin - B, W1, W1 and W3 - all massless.
The farthest back we can observe currently is the cosmic microwave background (CMB), resulting from the recombination event when electrons combined with hydrogen and helium nuclei to form neutral atoms, allowing photons to travel more freely through space. That was about 380,000 years after the big bang (t=10^13s) when the observable universe was about 85 million light years across*. Gravitational wave and neutrino observations might push closer to t=0s.
See my first answer. We are effectively within the cooled-down big bang. Our universe might also extend well beyond what is visible; much having passed beyond the cosmological horizon.
The current model is that all observers have essentially the same experience of the universe. In this isotropic model, such observers are called comoving observers because they move along with the Hubble flow - the motion of astronomical objects due to the expansion of the universe. The usual analogy is raisins embedded in a rising loaf of bread.
Does this mean that when the video talked about the Big Bang expansion initially being faster than light, that light wasn't free to trave at C, but was much slower due to this pre-recombination event?
Your are referring to wave length being stretched? Or is this some analogous velocity of energy traveling away from the origin point? You are talking about a pre-photon state of light, energy without mass or matter?
There were no photons before the electroweak transition. Everything travelled at c (not sure that can be proved - see below*). Nowadays, we understand that this is the limiting speed for all particles or indeed information that travel in the current era's vacuum state. The speed of light is a bit of an archaic term. Massless particles travel at c through space and 0 through time in their frame of reference. Everything else travels at c through space-time, so c through time in their frame of reference. There are suggestions that c must have been higher at very high energies as the wavelengths of the particle wave functions were smaller than the Planck length, but we're really not sure about what happens from a theoretical point of view under such extreme conditions. The mean free path length of photons during the radiation era before the recombination event and the transition to the matter era was limited by constant scattering off unbound protons and electrons. After that event, the mean free path became larger than the Hubble length (about 14.4 billion light years).
ESA - What is 'red shift'?
Actually, without rest mass; all objects in motion have effective mass due to their momentum, and energy has a mass equivalent through E = mc^2. I don't think B bosons and axions (a candidate for dark matter) are the same things. I believe their spins would be different (±1 and 0 respectively) and axions have a rest mass. Axions are predicted to be able to turn into two photons when they interact with strong electromagnetic fields (Primakoff effect) and the reverse transition is also theoretically possible.
The popular science explanation of Hawking radiation is completely incorrect - it was even propagated by Hawking himself for some reason about which we can now only speculate. I refer you to this article for a better explanation:
