MigL

As the Big Bang theory is an evolution of space-time, not a specific event, and it encompasses Inflationary theory. One of the reasons for Inflationary theories is the horizon problem. It arises because the only part of the universe we are in causal contact with, is the observable universe; so how did the parts outside the observable universe become homogeneous and isotropic ? At some time immediately after the initiation of the Big Bang, the universe had to have been in causal contact to allow light ( and information ) to cross the universe and establish an equilibrium . Inflation then provides many orders of magnitude expansion before settling down to its current rate, with the universe no longer in causal contact. Without the initial causal contact/equilibrium we would have a 'horizon problem', as we could not explain how the universe can be homogeneous and isotropic; inflation solves that problem.

How is that different from regular faith, Moon ? It just sounds much more 'pompous',

That the Earth is not flat is factual, and can be proven. That vaccinations are beneficial is also factual, and can also be proven. I stand by my claim that subjective opinions are NOT factual. Just like a rectum, everyone has one. And society decides which opinion is 'fashionable'; dissenting opinions only get you labelled, and the fashionable opinion 'du jour' must then be protected against the dissenting views. What the hell is 'revealed faith' anyway ? I may tolerate it,but I see no reason to protect such garbage.

Do you mean me ? I'm just trying to stir up a good discussion. ( almost managed to drag INow into it, unfortunately, I had to agree with him 😄 ) Are you saying that in the case of the OP, which references 'revealed faith' ( whatever that is ), discussion should be vetted by priests/rabbis/imans/etc. who have the actual 'expertise' ? I can see that working out really, really well ... I agree that universities are in a tough position, but fact based information cannot be easily dismissed. Opinion based information is a different matter; who is the arbiter of what is valid discussion, and what is conspiracy theory 'sucking all the oxygen from the discussion' ?

That video you posted is not PBS Spacetime, which can be a little speculative, but does an excellent job of explaining mathematical theory in terms of Physics. I do think you have gotten the wrong impression from the video, or others like it. The universe's topology has nothing to do with time dilation/length contraction. A toroidal universe is actually ( topologically ) flat around the short circumference, because it can be 'transformed' from a flat sheet. The long circumference, however, is not, but you ( and the video, are only considering three dimensions. Adding a fourth dimension doesn't allow for visualizing a 'doughnut' shape. What cosmologist use is a 'flat torus' which is best exemplified by the PacMan game, ( although I did own Atari computers and have played Asteroids ) and where going off one flat edge brings you to the opposite edge. The video does explain that one could ( if the universe was small enough or you could travel fast enough ) notice a difference in travel time, to get back to the original position, when going around the two different circumferences, but that is certainly not time dilation.

Well, let's see. A Einstein's GR predicted light would be bent in the curved space-time of a gravitational field. Sir A Eddington proved him right by observing the Solar eclipse in May 1919. If you live in North America, you can prove it yourself, next Monday; and you'll no longer be able to say, about light bending in a gravitational field, that Obviously, some things can be 🙂 .

Just like a card game at a casino in Atlantic City run by the mob.

Absolutely. But the only one that regularly demands protection from others' opinions, by taking even family members to court, is that joke of a former President, D Trump. But this is still in Astronomy and Cosmology ...

Stems from the new attitude permeating the Western world; that whatever you 'feel' cannot be wrong, and to even mention it can be offensive and you need 'protection' from other's opinions. Meanwhile science teaches us that what is right does not need protection, as it can be proven. But I don't know why this is in Astronomy and Cosmology ...

Could just be the material the shirts are made from. Workout shirts, for example, are made to 'wick' odorous sweat to the outer surface and evaporate.

I'm surprised she found America's actions 'offensive'. The Pacific theater in WW2 saw the death of an estimated 25 Million people, of which about 6 Million were combatants and about 110 Thousand Americans. Yet she finds the death of a couple of hundred thousand, to stop a brutal expansionist war that Japan started, offensive ? Or maybe she found the movie offensive, as it detailed the life experience of a man who helped orchestrate a turning point in history ? I just never realized morality has a PoV.

Seems that breasts bring out the child in all of us males ...

This discussion has its roots in Airbrush's claim that spatial expansion could be an explosion. I don't think Airbrush ( or Swansont/Mordred/me ) define explosion as you have. And while the mathematics you guys are posting are very interesting, and remind me of stuff I was once somewhat familiar with, they only match your definition , not the accepted definition of an explosion. After all, if you define a man as a woman, then Bob's your ... aunt ??

Mordred has already explained, but Wiki does also . "The scale factor � is a parameter of the FLRW metric, and its time evolution is governed by the Friedmann equations. The second Friedmann equation, �¨�=−4��3(�+3��2)+Λ�23, shows how the contents of the universe influence its expansion rate. Here, � is the gravitational constant, � is the energy density within the universe, � is the pressure, � is the speed of light, and Λ is the cosmological constant. A positive energy density leads to deceleration of the expansion, �¨<0, and a positive pressure further decelerates expansion. On the other hand, sufficiently negative pressure with �<−��2/3 leads to accelerated expansion, and the cosmological constant also accelerates expansion. Nonrelativistic matter is essentially pressureless, with |�|≪��2, while a gas of ultrarelativistic particles (such as a photon gas) has positive pressure �=��2/3. Negative-pressure fluids, like dark energy, are not experimentally confirmed, but the existence of dark energy is inferred from astronomical observations." From Expansion of the universe - Wikipedia

I think you guys had better define what an 'explosion' actually is. In no explosion, that I know of, is the speed of the fragments dependent on the separation between them. That only applies to an expansion.

Can't believe I'm actually weighing in on this, but ... A breast is mostly fat, glands and blood vessels encased in skin. That volume is somewhat fixed, and will only change depending on fat levels and hormone changes; not on the wearing of a bra or not. However, in men and women, the breasts are supported by muscles, and those adapt to stresses. Wearing a bra lessens the weight supported by those muscles, which would then atrophy and lead to more pronounced sagging. I don't imagine the effect is very large, but over a 30 year span, it might be. I recommend incline dumbell flies 🙂 .

It is common knowledge the emperor wanted an end to the war: the military leadership was of a different opinion.

Sure. But we know that the military leadership had promised to fight to the last man; I don't think starving hundreds of thousands would have mattered much to them. J Stalin and Mao Zedong starved millions to achieve their goals. I fail to see Airbrush's second guessing of the atomic weapon usage when he has no regrets of having used incendiaries to burn about 100000 people using chemical instead of atomic reactants in Tokyo. Additionally there were 4 fire bombing raids on Dresden, the first of which killed about 25000 people. I would guess the fire bombing of Tokyo and Dresden combined, killed almost as many as the two atomic weapons.

Because of the finite speed of light ( information ), objects ( events ) are separated by time as well as distance. At small distances the time separation is trivial, so we can safely ignore it.

Inflation would have started as a result of the drop from a false zero point vacuum energy due to a symmetry break. The last would have occurred at about 10-35 to 10-32 seconds, at least, according to most Inflation theories, the first of which was A Guth's inthe 80s. At this time, geometry ( and therefore space-time ) would already have 'formed', as that change, from the initial quantum foam occurred at Planck time, 10-43 seconds.

I hate doing laundry, so I take the least amount of time possible, IOW, no pre-soaking; it's a waste of time. Have three different hampers for colors, whites, and 'it doesn't matter'. Dump one of them into the washer with appropriate liquid detergent. Transfer them to the dryer with softener sheet for an appropriate time. You are done; and if a stain doesn't come out, toss that garment, and learn to be more careful next time. After the washing/drying comes the part I hate even more; folding and putting away.

Wheeew ! That's a long post, and I certainly haven't read and digested the whole lot, but if Mordred is willing to give your approach consideration, I can do no less. I'll start with the very first question ... Entropy is proportional to the number of degrees of freedom, or microstates of a system. The universe, pre-Big Bang ( whatever that means ), would have had no degrees of freedom, and only one state, until a possible quantum fluctuation set in motion the Big Bang evolution that results in ever increasing degrees of freedom, microstates, and entropy. Someone should tell Sean Carroll ( in your link ) not to over-think it; it could really be that simple.

This is an example of non-locality, or 'action at a distance'. ( IOW, an effect that cannot be realized with local variables, hidden or otherwise )

I love reading about these little European towns, Eise. I went to Schaffhausen to see the Rhinefalls. My cousin said they were the largest falls in Europe. I was thinking ( to myself "Have you seen Niagara Falls ?". And of course you can't get any lunch between 1 and 5 pm, so we crossed into Germany ( and me without my passport ) on our way to Basel. We stopped at a quaint little town called Waldshut-Tiengen and had a late lunch in what looked like a castle courtyard surrounded by shops and restaurants. My apologies for the veer off track, but I love Southern Germany, much more than Switzerland ( sorry Eise ).

Wow ! I didn't think that survived. Nice post, Eise.