This sentence jumped out for me. Is there some kind of crusade going on that I have missed the beginning of? This feels like a strange sentence in this piece and feels like a (misguided) attack.
https://arxiv.org/pdf/2207.09428.pdf
Suggests that the universe may be older than the Big Bang theory predicts. There are a lot of qualifiers on both sides of this, so I would suggest sitting back with some popcorn and enjoying the spectacle of a lot of primate descended life forms earnestly debating something that in many cases they couldn't even be bothered to read up on.
If so: https://youtu.be/I7lxzS6K9PU
Maybe save the unanswerable questions for after.
On the other hand, if you are working on theories that can extend into the early universe, it’s not unimportant to try and figure out where the model breaks down. Maybe t=0 isn’t possible, but t=1s? 1ns? 1ps? How much can we feasibly describe?
I’d argue that not exploring the limits of models is also bad science. Knowing the limits is a fundamental part of communicating a model.
The article we're discussing itself even links to one such paper [0]. All of the others she mentions are also published works - Penrose's CCC [1], the ekpyrotic universe [2], Hawking's no-boundary state [3] etc.
> On the other hand, if you are working on theories that can extend into the early universe, it’s not unimportant to try and figure out where the model breaks down. Maybe t=0 isn’t possible, but t=1s? 1ns? 1ps? How much can we feasibly describe?
Sure, but this is a different thing. Many of these are adding elements to the existing theories, and then predict a new initial state given the modified evolution laws.
[0] https://link.springer.com/article/10.1007/s10714-021-02790-7
[1] https://arxiv.org/abs/1808.01740?context=astro-ph
They're not publications of "what is definitely true", they are fundamentally explorations of what could be, or the more important "this is kind of interesting where could it lead?".
But the thing is, theories about the beginning of the universe will never be testable, they aren't just not currently testable.
So, if your theory has no novel predictions about the future, but it adds extra parameters to obtain a different prediction about a past which exists beyond what can be measured, then you're wasting your time creating this theory, and wasting reviewers' and readers' time publishing it; and you're wasting money researching it.
This is what Sabine usually writes and complains about - research money being spent on research that is at best unlikely to bear any fruit, and at worst navel-gazing, especially when there are very real problems in physics that are not receiving significant research.
This is why she complains about people researching the beginning of the universe, or black hole entropy, or grand unified theories, or the hierarchy "problem", or looking for supersimmetry or for WIMPs in ever larger particle accelerators.
Instead, she wishes more people were researching the measurement problem, non-linearity in quantum mechanics, high-energy physics through radio-telescopes instead of particle accelerators, to name a few things.
Now, I don't know anywhere near enough to say that she is right, but I do believe she is not trivially wrong, like you seem to be suggesting.
If she was a software developer we'd rightly start to wonder about grand pronouncements coming from someone no longer practicing in the field.
When your market doesn't exist if you actually agree with anyone, the incentives start to be questionable.
What are you talking about?
She is still publishing proper research papers as recently as this month!
https://arxiv.org/search/?searchtype=author&query=Hossenfeld...
Some people pick up weird ideas about her and I really wonder why.
However her broad ranging commentary which tends to take the tone of "this field should listen to me but doesn't" as is the case with this article (and a few others she's done such as about the LHC[2] or black-hole information loss[3]) leaves a sour taste in my mouth.
[1] https://www.fias.science/en/fellows/detail/hossenfelder-sabi...
[2] http://backreaction.blogspot.com/2020/10/particle-physicists...
[3] http://backreaction.blogspot.com/2022/04/i-stopped-working-o...
Our best cosmological theory applied backwards results in singularity. That's bad. See her droplet example.
According to maximally projected Penrose diagrams in singularity time and space evert into the multiverse. You move in time and space flows around you. https://youtu.be/4v9A9hQUcBQ
And according to our other most successful theory, space-time is divided into chunks. And boiling. Opposite of infinitely divisible, smooth relativistic space-time.
Not to mention if we go with current astronomy theory, we end up with unexplained dark matter and dark energy, that give different answers depending on the methodology.
Whether time has an origin, and whether we can measure how distant it is from us are questions that could be answered.