But Head's innings will make them double down on this approach!

The bowling does look good. The batting is continuing the theme of the NZ ODIs though.

I mean, cosmologists will probably guess what this is about (it's about me wondering if they do things differently in Cambridge for some reason)

FFS

So on the one hand, maybe some small progress on the theory side making it easier to come up with models that can explain the data.

On the other hand, on the data side things are still moving with supernovae, and the evidence that there is something to explain is now a little bit weaker! 🧪🔭

In summary: this paper says that one of the things some thought was a big problem with creating physical DE models that describe the data isn't actually a problem at all.

(There are still other problems though, and it is hard to construct such models, as they acknowledge.)

... the total still always decreased, because DE was only a small fraction of the total at the time, and the other components decreased.

They also show how DE made up of multiple fields, which all have w>-1, can be mistaken for a single DE field with an "effective" equation of state w<-1.

The NEC essentially says the total energy density of the universe cannot grow with time as spacetime expands.

This paper argues this applies to the total of all components of the universe, and not to DE alone. While the data suggest the energy density of DE increased with time in the past ...

In particular, it looks like dark energy would need to have an equation of state w(z) that is both hard to achieve in physical models, and - apparently - violates the Null Energy Condition, which we believe should not be violated.

This new paper argues apparent NEC violation is a misunderstanding.

The second paper today was a theoretical one, on models in which dark energy might evolve in the way the data seem to suggest: arxiv.org/abs/2511.07526

A major reason why the DESI results have been so interesting/controversial is because to explain them dark energy would need to be WEIRD

One very minor point on the other side of the ledger is to point out that when a large collaboration put out their "key project" results, these face a lot of internal scrutiny from very many people. This reanalysis is the work of a much smaller team within DES. That need not mean much of course!

What should we make of this? Well, the change certainly goes in the direction many people might have been expecting. And newer analyses do build on older ones and in general (we would hope) correct previous flaws so are more robust.

The net result of these changes is to slightly change the cosmology implications: reducing the 4.2σ significance of the evidence for evolving DE to just 3.2σ. Compare the shift in the small blue and grey contours in the zoomed in second figure here:

This new paper from the Dark Energy Survey team reanalyses their data, changing (hopefully improving) various different aspects of the analysis, and finds that as a result the data points shift a bit, in different directions at different redshifts
arxiv.org/abs/2511.07517

This was a pretty explosive result! But it has always been clear that if there was a weak link in the chain of reasoning here, it would be in the supernova data. Not least because other SN datasets and processing methods have slightly different answers. SN are hard, and messy.

So back in March we showed that if you combine BAO data from DESI with supernova data from the Dark Energy Survey and CMB data from Planck and other experiments, evolving dark energy is preferred over the standard cosmological constant model, at the 4.2σ level.

Extraordinary how the orphan they trained continued to produce so much amazing music very much in the way the original did

despite not having vocals, 'kind of blue' is actually the first kind

There are three types of jazz: smoky voiced female vocalist sings song that sounds like it’s about sex but is actually about racism; 9 woodwork teachers on a stage shout “chase that tiger” while somebody hammers a piano; man has a heart attack whilst trumpet playing and falls downstairs.