Hakeem Oluseyi

Thank you, thank you.

Thank you, thank you.

So now there's new... James Webb Space Telescope data.

So now there's new... James Webb Space Telescope data.

So we had a similar problem with the ages of stars and the age of the universe, which depends on the Hubble thing, right? And so it was the cosmological data that had to be adjusted.

So we had a similar problem with the ages of stars and the age of the universe, which depends on the Hubble thing, right? And so it was the cosmological data that had to be adjusted.

That's right. Stars in the halo looked like they were older than the age of the universe, right? And the headlines were, oh, catastrophe. Oh, my God. Yeah, people like ready to give up on the universe. But then we realize, oh no, our cosmology needs to be improved. And so, you know, what happened in the 90s, really, you know, post-Kobe, that changed everything in cosmology, right? Not Kobe Bryant.

That's right. Stars in the halo looked like they were older than the age of the universe, right? And the headlines were, oh, catastrophe. Oh, my God. Yeah, people like ready to give up on the universe. But then we realize, oh no, our cosmology needs to be improved. And so, you know, what happened in the 90s, really, you know, post-Kobe, that changed everything in cosmology, right? Not Kobe Bryant.

Not Kobe Bryant.

Not Kobe Bryant.

Nobel laureates, yeah, yeah.

Nobel laureates, yeah, yeah.

Yeah, something's got to give. So I think that there's something that we don't understand. I think I'm trusting the measurements, and I think that I trust the theory. The measurements look good, don't they? The measurements look good. I was involved in supernova cosmology, right? And also weak lensing studies for looking at structure of growth and these sort of things.

Yeah, something's got to give. So I think that there's something that we don't understand. I think I'm trusting the measurements, and I think that I trust the theory. The measurements look good, don't they? The measurements look good. I was involved in supernova cosmology, right? And also weak lensing studies for looking at structure of growth and these sort of things.

And so all this different data, there's more than one probe, right? People are using different types of stars.

And so all this different data, there's more than one probe, right? People are using different types of stars.

Or do we just have to adjust the model? Well, people come up with these models that may be the expansion rate of the universe. We have it like, okay, there's this initial impulse, right? And then the universe evolves based on the energy densities of the constituents, of which there are three main ones, right? Radiation, which is stuff that moves very fast through space, but almost...

Or do we just have to adjust the model? Well, people come up with these models that may be the expansion rate of the universe. We have it like, okay, there's this initial impulse, right? And then the universe evolves based on the energy densities of the constituents, of which there are three main ones, right? Radiation, which is stuff that moves very fast through space, but almost...

not at all through time, matter, which moves very fast through time and almost not at all through space, and space-time, which has its own energy density that we call dark energy, which doesn't move through either one, right? And so initially, radiation dominates, then matter comes to dominate, then dark energy, i.e. space-time energy density, comes to dominate. We think.

not at all through time, matter, which moves very fast through time and almost not at all through space, and space-time, which has its own energy density that we call dark energy, which doesn't move through either one, right? And so initially, radiation dominates, then matter comes to dominate, then dark energy, i.e. space-time energy density, comes to dominate. We think.