I have mentioned cosmological work from Sir Roger Penrose, a British mathematical physicist, in-passing a few times in the past, but have never zoomed in a bit. Despite the fact that his work in general relativity is more highly regarded than his cosmology work, the latter has recently evoked some renewed interest among the Cosmo-community. He came up with an interesting variant of his earlier (discredited?) cyclic cosmological model proposals, now called Conformal Cyclic Cosmology (CCC).

So what has changed to evoke the new interest? CCC is technically tough to follow, but in a nutshell, he performs a conformal rescaling at time > 10100 yr (one Googol year) that equates the then cold empty space to the hot Big-bang, without the inflationary period. It does two neat tricks: Firstly, it resets the universe's entropy to a low value again without needing inflation; Secondly, it allows signals from our cycle (aeon) through to the next aeon. Likewise, signals from the preceding aeon have been allowed through to our aeon. He claims that their signatures have already been observed in the CMB radiation - by both the WMAP and Planck missions. Interesting!
There are many talks and interviews with sir Roger recorded in the last few years. Instead of doing an injustice to his work, I recommend this particular talk of mid-2019 at the Paris Astrophysics Institute: "Are we Seeing Hawking Points in the Microwave Sky?". Penrose's 'Hawking points' are Hawking radiation from evaporation of mega-massive black holes near the end of the previous aeon, that are posited to have left a defined imprint on the CMB.
The video sports clear hand-drawn graphics with the typical Penrose clarity of explanation, which is amazing for a (then) 88 year old. It is a tad long (1h10m), but well worth the time. After the initial introductions, he starts talking about 5 minutes into the YouTube video. But be aware: once the talk starts, it is difficult to stop watching - so pick your time.
I noticed that he has lately been invited by many science popularizers to their podcasts and public discussions. I get the feeling that some inflation- and string-threorists are trying to get him off their backs. I can imagine that their students are asking difficult questions about sir Roger's ideas, so they can't ignore him anymore...
I did a wee-bit of self-study into CCC, so you are welcome to ask my opinion, once you have watched the video (I can't compete!).
J-
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