Cosmogenesis .

[unbeliever]

So are we talking about an observed breaking of CP symmetry here then? I've not kept up on this side of things recently.

 

Indeed. The first observation was in Kaons in 1964 by James Cronin and Val Fitch. They won the nobel for it in 1980.

It was also observed in b-mesons I think in the '90s.

However there is still not enough observed CP violation to account for the matter/anti-matter asymmetry and the hunt is on for more.

There are hints from d-mesons and there are multiple processes in b-mesons which is why the accelerator folk build b-factories to generate as many b-mesons as possible and then watch them decay.

Edited May 4, 2016 by unbeliever

[truman]

I know it's a very simplistic question and I must be missing something but,if the big bang happened 14 billion years ago and nothing can travel faster than light then how can the universe be 46 billion light years across?Wouldn't the biggest diameter possible be 28 billion light years?

Edited May 4, 2016 by truman

[unbeliever]

I know it's a very simplistic question and I must be missing something but,if the big bang happened 14 billion years ago and nothing can travel faster than light then how can the universe by 46 billion light years across?Wouldn't the biggest diameter possible be 28 billion light years?

 

For weird reasons the maths of which makes my head hurt a lot, the space-time itself is allowed to expand faster than the speed of light.

This is one of the reasons people talk about "warp" drives and such as ways to get around the speed limit. Whilst you can't travel through space that fast, if you could persuade the chunk of space your in to move for you, that's okay.

[Cyclone]

I'm aware. But this does not invalidate the question.

 

---------- Post added 02-05-2016 at 12:27 ----------

 

The leading hypothesis for the cause of cosmogenesis in physics is probably that it arises from a large fluctuation in vacuum energy. The original idea dates back to at least 1973, but has only recently become popular.

 

Fluctuations in vacuum energy occur within the universe all the time. A pair of particles with all properties (charge, energy, mass etc) cancelling each other out is briefly born and then dies as the 2 particles cancel each other out.

 

A key prediction of this hypothesis is that the total energy of the whole universe should add up to zero. The hypothesis has gained popularity since 1998 when "dark energy" was effectively discovered as a result of observations of type 1a supernovae showing that the rate of expansion of the universe has increased with time. This dark energy brings the estimates of the total energy of the universe down to close to and consistent with zero. Without dark energy, it was nowhere near.

 

 

I mention this partly because I think it helps inform the debate in of itself, but also to try and convince you that cosmogenesis is susceptible to investigation using the scientific method.

You may have been told that questions about before the big bang are somehow meaningless or unanswerable. This is only partially true.

No kind of telescope: optical, radio, neutrino, gravitational etc; can in any way "see" before the big bang. However that does not mean that there are not a lot of facts which can be gathered which I suspect will ultimately reduce the number of plausible scenarios to one.

 

https://en.wikipedia.org/wiki/Zero-energy_universe

https://en.wikipedia.org/wiki/Accelerating_expansion_of_the_universe

 

Our very language makes it all rather difficult to talk about.

 

You said "before" the big bang, but if that was the origin of time itself then there is no "before" that.

[sutty27]

I know it's a very simplistic question and I must be missing something but,if the big bang happened 14 billion years ago and nothing can travel faster than light then how can the universe be 46 billion light years across?Wouldn't the biggest diameter possible be 28 billion light years?

 

Edit, didn't read you question right.

Edited May 4, 2016 by sutty27

[DnAuK]

I am of the opinion that it didn't start and will never end, but the tiny bit that we live in and can see expanded from a very hot very dense part of an already existing universe and it will one day cool and die.

 

I'm no scientist, well - certainly not as much as some of you on here, but I actually think this is quite a clever possible explanation. I'm not sure Sutty was suggesting a 'multiverse' as such - just an extremely large universe of which we usually only see one little bit.

 

It has already been pretty much proved that a supermassive black hole sits at the heart of all galaxies we can see. In fact they have recently discovered a 'unbelievably massive' black hole at the heart of a neighbouring galaxy which they feel can only have come about by multiple supermassive black holes merging.

 

Now suppose this happens, quite regularly in cosmic terms, and we end up with everything in the local galactic cluster swallowed up by one '****ing huge black hole' which then reaches a critical mass and, well, explodes in 'big bang'. That kinda fits with the theory of how the universe came to be but, in effect, would only be responsible for 're-creating' a portion of it.

 

This may also explain why other parts of the universe appear to be accelerating away from us at a greater rate - they were simply created in their own, different, 'big bangs' and expanding in the opposite direction to us. Thus removing the need for 'dark energy'.

 

Or, I could be talking bullcr@p as usual...

[Cyclone]

Now we have the problem of how we define nothingness, are we talking about the vacuum of space which is something, or are we talking about non existence not even the vacuum of space, if its the latter how do we even know that nothingness is even possible.

 

An empty space within our universe is not "nothingness" in the same way that there would be nothing if the universe didn't exist.

It's the none existence of space and time, not just an area with no physical object in it.

[truman]

If two points in space are moving apart at light speed they will appear to be travelling twice the speed of light from each point.

 

The two furthest point of Light from an explosion will always be twice the speed of light apart.

 

I'm not so certain about your first assumption.. as for your second that's why I said the maximum diameter I would have expected was 28 billion light years.

[Obelix]

I know it's a very simplistic question and I must be missing something but,if the big bang happened 14 billion years ago and nothing can travel faster than light then how can the universe be 46 billion light years across?Wouldn't the biggest diameter possible be 28 billion light years?

 

Nothing can travel faster than light OK? That's kind of accepted as given. So you'd expect that nothing can expand faster than light speed.

 

Take a balloon mark a load of galaxies on it like a raisen pudding and blow the balloon up - that's the expanding universe.

 

Now, if you blow it up so fast that the edge is expanding at light speed, when measured to the other edge, then within the universe, everything is expanding at much less than light speed in relation to each other.

 

So you can blow it up faster and the edges are receding at faster than light speed, but still within the universe, everything is expanding at much less than light speed.

 

Best explanation I can give without some fearsome maths that I really don't want to have to try to understand again...

[sutty27]

An empty space within our universe is not "nothingness" in the same way that there would be nothing if the universe didn't exist.

It's the none existence of space and time, not just an area with no physical object in it.

 

If that's how physicists define nothing, how do they know it's possible, and what mechanism do the assume exists which would allow the universe to expand out of it?

 

---------- Post added 04-05-2016 at 11:04 ----------

 

I'm not so certain about your first assumption.. as for your second that's why I said the maximum diameter I would have expected was 28 billion light years.

 

I edited because I didn't read your question correctly.