Or just invent a ‘free’ source of effectively limitless usable energy (such as cold fusion) - which could make experiments and technologies possible that we cannot easily imagine?
That’s definitely not going to happen in my life time. I’ll be happy if there is a small station on the moon by then. AFAIK the most likely current plan is simply the larger 100 km tunnel at the CERN site, and it will take long enough. Though there are some other plans. Of course the Chinese might come to rescue, we know what they can do (and not care so much about some side effects).
Of course, but if there is no surprising breakthrough hot fusion alone will take decades. Probably our best bet anyway in order not to have to care more about a billion climate refugees instead of colliders 
The physics of the Big Bang has often evaded me at even a basic level because cosmologists seemed to prefer to shroud it all in the mathematics of General Relativity. I watched many of Leonard Suskind ( a father of String Theory)’s Lectures on GR before Christmas and at least thought more about the age of the Universe and how it can be that Webb will look back to a few hundred million years after the BB.
The only model I could come up with was that at time zero the stuff was exploding at close to the speed of light and continued to do so. However, GR theories replace this with metrics describing space itself as expanding in a time dependent way. After a few minutes of expansion the Universe was cool enough for the first particles to form and protons and neutron to combine to form helium. The mass density everywhere was equivalent to that of our atmosphere (there is an awful lot of nothingness now and then energy dominated over matter) . Apparently it took another 379,000 years before the electrons could be captured to form hydrogen and helium atoms at which point there was light as opposed to much higher energy radiation.
The thing to remember is that as time passes the distance between points in space time increases and we so we see back into the past. GR is about energy (matter being a form of energy) defining the curvature of space and space telling everything including light how to move. Once there is no net electric charge what we call gravity dominates, and being thought of as an attractive force gradually the expansion slows down.
For the last 100 years theories have preferred to think that we are not in a special part of space (isotrophy and large scale homogeneity). The implication of being able to look back to 300 million year from the BB is that light from that time has taken 13.4 billion years to catch up with the matter in our local part of the universe. Clearly the stuff our local part is made of must have been expanding close to the speed of light for a long long time. The same applies to those distant early objects which will now see the matter our local region emerged from in the same way.
Red shift is all about relative velocity because Special Relativity requires we abandon the concept of some absolute rest frame. I had not realised that in Jan 2020 Hubble astronomers had discovered a quasar with a red shift of 7.64 meaning the wavelength of the photon is 7.64 longer. The implication is that quasars and therefore black holes existed in early galaxies.
The amazing thing I learned from Brian Cox’s Universe series last autumn is that Hubble allowed us to see so far back to the early universe. Those galaxies are completely different to the one in our local region. It’s not even fair to describe them and the stars in our galaxy as the same. That for me is why James Webb is so exciting.
Lots of theories of physics will be put to the test over the next few years!
Phil
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Ah so this is was what you have been doing while your avatar kept popping up 
I have to read this more closely, but a few points
- Nothing exploded
- The expansion of space is not limited by the speed of light
- Observations required to postulate dark energy because expansion is not slowing down but speeding up
What I am bothered by about the first moments after the “big bang” is inflation. It explains a awful lot of things, but kind of feels like a cop-out.
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It is all beyond comprehension but we have to think in terms that are, so no apologies for language used! LHC and it’s successors can only allow infinitesimally small amounts of energy to be concentrated albeit large in terms of the energy of normal matter we are studying. That is why there is such a gulf between QFT and GR. Physics is about theories explaining what can be measured. Theories allow us to propose new things to measure. It’s an ever decreasing circle. At some time new theories have to be more than just assertions though.
Phil
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Yes - now we are going full interdisciplinary ‘Padded Cell’ (in the Lounge) 
I’ve just cycled home from the office and put on my favourite ‘cheesy’ lounge jazz album to celebrate!
I do like the first clause in this sentence.
That the weak force of gravity only applies on scales large enough for gravity not to be overwhelmed by electromagnetism.
Is this a known finding/cause of the split between quantum and macro realms?
This doesn’t make sense to me, prima facie, as you have written it, Phil.
You cannot be referring to stuff like planets and suns.
You could mean that our galaxy or local group is retreating from (certain other ones) at close to the speed of light, which we know is the case.
In fact, I think it’s generally agreed that our galaxy is getting further away from extremely distant galaxies within the observable universe much faster than the speed of light, because they are actually moving through space, space is expanding between them at accelerating rate pushing regions on space away from one another ever faster.
This expansion of space is not supposed to be effective at the scale of people, planets or even within galaxies.
The Flaming Lips: “What Is the Light? (An Untested Hypothesis Suggesting That the Chemical [In Our Brains] by Which We Are Able to Experience the Sensation of Being in Love Is the Same Chemical That Caused the “Big Bang” That Was the Birth of the Accelerating Universe)”
Good night!
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Yes, the idea of the BB as a cosmic firework is poetic, but wrong. Because explosions slow down as they progress, whereas the expansion of the observable universe is speeding up.
That’s not an explosion, it’s something that seems to create ever more spacetime as it progresses!
Did ‘the universe’ have a singular moment of creation ex nihilo?
This seems to be an over extrapolation of the thought experiment of reversing the process of an expanding universe that is accelerating in its expansion.
It doesn’t have to go all the way back to an infinitesimally small singularity.
It could.
But it doesn’t have to.
Inflation could be a path to something other than zero…
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So many questions! We don’t know the answers. Hopefully JW will give us more information to mull over. I was only trying to explain my way of understanding how we can look back to the early days of the universe.
Given GR tells us space has curvature the concept of infinite Euclidean space has to be ditched. In our current era of the universe space is only slightly curved though. I wonder what the theorists think it was like during its infancy!
Phil
Yes, this is where Physics and its models and data break down, and human stories and logic are smashed on the rocks of the unknowable and un-testable.
I don’t despair. After all Einstein found news ways of thinking about some of the small anomalies that existed. It took him 10 years to learn the mathematics needed to formulate his theory of GR. Most of the mathematics needed was already there.
If you have time watch Leonard Susskind’s lectures on YouTube. There is a common theme to the formulation of GR, Classical Mechanics and Dirac’s QM: Diffential and Integral Calculus, Vectors and Tensors and their use in expressing physical concepts and performing calculations. I would need to work hard to become fluent, but Susskind’s lectures show the way. Methods of teaching were not as good 50-60 years ago.
Much of modern physics boils down to concepts of conservation, symmetry and equivalence. QM principles are quite simple to express but the mathematics mind boggling.
Phil
I have literally just finished this. He is perhaps not the best of those writing about cosmology/quantum physics for the amateur reader (Brian Greene is the best IMHO) but the book does at least present an argument that the world of Quantum Dynamics etc is affected by serious groupthink and he argues a place for those who promote different ideas. His theories are built around a principle of ‘realism’ vs the bizarre ‘unrealities’ of QD. Hard to explain further-you may have to read the book!
Bruce
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The problem with QM is that it works so well which created a very high bar
Yes, QM is very useful theory for instrumental purposes.
Horrible theory for helping us understand what the world/universe actually is.
Now it’s fragmented into a set of incompatible interpretations.
David Bohm wrangled with the problem of trying to make QM make sense all of his life, brilliantly in some ways, and with some success.
I enjoyed Smolin’s book ‘The Life of the Cosmos’ some years ago.
Indeed, it works so well and makes no sense. There’s no reason for the 26 or whatever constants in the standard model, they are just there in experiments and are confirmed every time, but this doesn’t imbue them with any cause or meaning.
Still, any alternative has a high bar to clear regarding its predictive power.
Probably nobody believes that the Copenhagen interpretation makes sense, but it’s still taught because it works in practice. Then you have alternative interpretations like many-worlds, which takes the wave function by its word (or by its math, as it were) and is in this sense more satisfying, but is not without problems either, and even if it were, leaves one baffled.
Oh well, future generations need something to do as well