Problems in Cosmology
It is refreshing to see cosmologists admit and openly discuss the problems in cosmology. As any interested observer can see the problems are huge and getting worse, not better.
Lambda Cold Dark Matter (LCDM), as the scicommers are keen to emphasise, explains a great deal about the structure of the universe. But how much does it tell us about the big questions of cosmology?
Cosmology:
“the scientific study of the origin, evolution, and eventual fate of the universe” Wikipedia.
It tells us nothing about where all the stuff of the universe came from.
Tells us little about how the universe will end.
Even worse, it leaves 95% of our universe unexplained. Even the placeholders for this 95%, Dark Matter and Dark Energy, are being questioned more and more.
Dark Matter? Not only can we not detect it, we have no idea what it is. Even worse its very existence is being questioned.
Dark Energy? “An unknown form of energy that affects the universe on the largest scales. ... Without introducing a new form of energy, there was no way to explain how an accelerating universe could be measured”. Wikipedia.
Not only are the usual explanations of Dark Energy totally unsatisfactory - “the energy of the vacuum which doesn’t dilute as space expands”. Even its existence is being questioned by some recent papers on supernova measurements.
It is not surprising therefore that those who have committed their energy and skills to the subject get a little tetchy when us amateurs see an opportunity to make suggestions.
The field of cosmology is a natural for the amateur scientist; a pastime which was once honourable, but is too often today scorned by the professionals. Any enquiring mind wants to know how it all started and how it will end. When those answers are not forthcoming, one is obliged to search for an explanation. It is natural to feel the need to fill that void.
Obviously such a task is going to be near to impossible. The best brains have been at it for centuries and LCDM is the paradigm of today. It best explains the observations, they say. It's a tightly knit and interconnected model. Woe betide anyone who tinkers with any part of it. Any new model must explain all that LCDM explains and more. We're not allowed to cherry pick from the data.
The answer is always; more data, better data. The problem is, the more data we get, the bigger the problems become.
More and better data on the expansion of the universe hasn't answered the issue of the Hubble constant (Ho). It's made it worse.
So yes, Cosmology has some serious problems. To those trying to defend LCDM I turn to Stacy McGaugh’s blog January 29 2019:-
“we should remember that we once endowed SCDM with the same absolute certainty we now attribute to ΛCDM. I was there, 3,000 internet years ago, when SCDM failed. There is nothing so sacred in ΛCDM that it can’t suffer the same fate, as has every single cosmology ever devised by humanity.”