The ultimate fate of the Universe

[andrew s]

If it is not to be the big rip of popular science (technically the scale parameter going to infinity in a finite time) then what. The current LCDM model predicts an exponentially expanding universe but the "tension" produced by the expansion is not strong enough to overcome gravity at the local cluster scale so what happens.

According to this document http://math.ucr.edu/home/baez/end.html by the respected scientist John Baez it will just all evaporate away. Easy to read and no equations.

Regards Andrew

PS for fun, and due to the permanent cloud we seem to have, I have been taking Leonard Susskin's video General Relativity course. At the start of lecture 3 he says something along the lines of "People say GR is hard - pregnant pause - that's because it is". I now have a "tensor" headache.

[Knight of Clear Skies]

Some say the world will end in fire, some say in ice.

Personally I favour the explanation that it will all be eaten by mice.

In a similar vein, Ethan Siegal has a recent article on fours ways the Earth will end - and we don't make it past the first one.

[jetstream]

I'm beginning to wonder if there ever will be a predictable outcome during the period humanity is still alive. I'm also thinking the habitable earth will be long gone before the universe does its thing- whatever it is.

[George Jones]

59 minutes ago, andrew s said:

PS for fun, and due to the permanent cloud we seem to have, I have been taking Leonard Susskin's video General Relativity course. At the start of lecture 3 he says something along the lines of "People say GR is hard - pregnant pause - that's because it is". I now have a "tensor" headache.

 

Quantum theory is much harder, both conceptually and technically, than general relativity.

[andrew s]

3 minutes ago, George Jones said:

Quantum theory is much harder, both conceptually and technically, than general relativity.

That's not me experience it's all those upper and lower tensor indices that drive me mad. Maybe I gave up trying to visualise QED long ago while I still try to picture the classical world of QR.

Regards Andrew

[Delasaurus]

The ultimate fate of the Universe is as it's always been..the Universe will continue to do what it needs to do and has done for eons. The fate of us mortals here on Earth however, is a different matter. The Universe couldn't care one iota about us (humans) and if we believe as humans that we have the power to challenge the Universe otherwise, then we really have lost the plot. It would be like trying to tame the Oceans.

We might think we are smart but the Universe has other plans for us. Which is where certain belief systems can kick in to subdue our most definite mortallity as a species. Science for all it's worth, will never take the upperhand to the great mystery. It cannot and will not ever be solved because it is insolvable. Trying to portray what the end of the Universe will be like is like trying to pin the tail on the donkey. We have hardly scratched the surface about what we know of the Universe at present. And when we take my infamous 'time concept' .. in the scale of Universal time, we will never know because time would not have existed outside of our own making. The Universe knows no time, only humans know of time. In a blink, it was created, in a blink it's gone and after we have gone...there will not even be a labelmaker left in the Universe, to call it a Universe. We can therefore, only project our scientific knowledge to a certain threshold before it begins to fail as a working model of the Universe. Indeed, science tells us that parts of the Universe don't exist, vanished years ago.

Perhaps we need to philosophically reverse the question before we can attempt to answer it's fate. How can we prove the Universe exists?

It's a bit like  poor old Liebnitz really, who tried to prove the existance of a certain ol boy with 1's and 0's on his sliderule..he went mad!

So we can see the torch beam but is it still there when we shut our eyes for good? Back to Schrodingers Cat.

[George Jones]

Baez's paper is very nice.

 

2 hours ago, andrew s said:

That's not me experience it's all those upper and lower tensor indices that drive me mad. Maybe I gave up trying to visualise QED long ago while I still try to picture the classical world of QR.

Regards Andrew

 

I am not sure about physics programmes in the UK, but, in North America,  I think that students find quantum theory easier than GR because they spend more time studying quantum theory.

A longer more personal version of this comment:

https://www.physicsforums.com/threads/is-gr-harder-than-qm.607638/#post-3925089

[ollypenrice]

If you want to know everything, don't choose science. Science is all about what we don't know.

Olly

[andrew s]

1 hour ago, George Jones said:

A longer more personal version of this comment:

https://www.physicsforums.com/threads/is-gr-harder-than-qm.607638/#post-3925089

Are that George Jones. I find "physicsforums" a god send for new ideas and current thinking - that's where I pinched the link from.

Although I agree with your comments in the post in your link I have had to relearn QM/QED and GR as they were not covered in my undergraduate course oh so long ago and I then did an experimental PhD in solid state physics. Following that it has just been a hobby along with astronomy.

Regards Andrew

[ollypenrice]

13 hours ago, andrew s said:

Are that George Jones. I find "physicsforums" a god send for new ideas and current thinking - that's where I pinched the link from.

Although I agree with your comments in the post in your link I have had to relearn QM/QED and GR as they were not covered in my undergraduate course oh so long ago and I then did an experimental PhD in solid state physics. Following that it has just been a hobby along with astronomy.

Regards Andrew

Good credentials! Don't beat yourself up...

Olly