Brian Cox

Yeah. And we've inferred it. So you might say, how do you know it's there? You know, which is a good question, right? I mean, if we have not detected this stuff, how do you know? And it's from Einstein's theory, really. So it's from gravity. It's from looking at the way that galaxies rotate and the way that these sound waves move through the early universe and the way that the universe expands.

Yeah. And we've inferred it. So you might say, how do you know it's there? You know, which is a good question, right? I mean, if we have not detected this stuff, how do you know? And it's from Einstein's theory, really. So it's from gravity. It's from looking at the way that galaxies rotate and the way that these sound waves move through the early universe and the way that the universe expands.

Yeah. And we've inferred it. So you might say, how do you know it's there? You know, which is a good question, right? I mean, if we have not detected this stuff, how do you know? And it's from Einstein's theory, really. So it's from gravity. It's from looking at the way that galaxies rotate and the way that these sound waves move through the early universe and the way that the universe expands.

Because the way the universe expands is related to the stuff that's in the universe. So we can weigh the universe and find out what kind of different things are in there by looking at the way it's expanded and how that expansion history has changed over time. So what you do with science, which is why it's true that you can criticize any one bit of it, and people will.

Because the way the universe expands is related to the stuff that's in the universe. So we can weigh the universe and find out what kind of different things are in there by looking at the way it's expanded and how that expansion history has changed over time. So what you do with science, which is why it's true that you can criticize any one bit of it, and people will.

Because the way the universe expands is related to the stuff that's in the universe. So we can weigh the universe and find out what kind of different things are in there by looking at the way it's expanded and how that expansion history has changed over time. So what you do with science, which is why it's true that you can criticize any one bit of it, and people will.

So online you'll see in the comments under this, there'll be people saying, what about this, what about this, what about this? And it's true that you can pluck away and pick away any piece of it. But the way it tends to work is when you have this kind of consensus view of something, it's because you have multiple observations that all fit a particular hypothesis.

So online you'll see in the comments under this, there'll be people saying, what about this, what about this, what about this? And it's true that you can pluck away and pick away any piece of it. But the way it tends to work is when you have this kind of consensus view of something, it's because you have multiple observations that all fit a particular hypothesis.

So online you'll see in the comments under this, there'll be people saying, what about this, what about this, what about this? And it's true that you can pluck away and pick away any piece of it. But the way it tends to work is when you have this kind of consensus view of something, it's because you have multiple observations that all fit a particular hypothesis.

And by changing one of them, by changing the explanation of one of them, you tend to mess the whole other thing up. You mess the wider description of multiple phenomena up. You mess it all up. So it's quite hard to find other theories at the moment that will fit all of those different observations. I mean, another example would be the age of things.

And by changing one of them, by changing the explanation of one of them, you tend to mess the whole other thing up. You mess the wider description of multiple phenomena up. You mess it all up. So it's quite hard to find other theories at the moment that will fit all of those different observations. I mean, another example would be the age of things.

And by changing one of them, by changing the explanation of one of them, you tend to mess the whole other thing up. You mess the wider description of multiple phenomena up. You mess it all up. So it's quite hard to find other theories at the moment that will fit all of those different observations. I mean, another example would be the age of things.

It's interesting that you can look at, we can measure the age of the Earth, right? And you measure it from geological processes, radioactive dating and so on, and you can kind of measure the age of the Earth. You can measure the age of the sun in a different way. You can measure it by looking at what's called helioseismology. So you can measure how much helium is in the core of the sun.

It's interesting that you can look at, we can measure the age of the Earth, right? And you measure it from geological processes, radioactive dating and so on, and you can kind of measure the age of the Earth. You can measure the age of the sun in a different way. You can measure it by looking at what's called helioseismology. So you can measure how much helium is in the core of the sun.

It's interesting that you can look at, we can measure the age of the Earth, right? And you measure it from geological processes, radioactive dating and so on, and you can kind of measure the age of the Earth. You can measure the age of the sun in a different way. You can measure it by looking at what's called helioseismology. So you can measure how much helium is in the core of the sun.

And the sun shines by making helium from hydrogen. So by measuring the amount of helium in the core, by looking at basically sound waves, it's like an earthquake that sunquakes. You can measure how much helium is in there so you can get an estimate of the age of the sun. And then you can get an estimate of the age of the universe by measuring how it's expanding and using Einstein's theory.

And the sun shines by making helium from hydrogen. So by measuring the amount of helium in the core, by looking at basically sound waves, it's like an earthquake that sunquakes. You can measure how much helium is in there so you can get an estimate of the age of the sun. And then you can get an estimate of the age of the universe by measuring how it's expanding and using Einstein's theory.

And the sun shines by making helium from hydrogen. So by measuring the amount of helium in the core, by looking at basically sound waves, it's like an earthquake that sunquakes. You can measure how much helium is in there so you can get an estimate of the age of the sun. And then you can get an estimate of the age of the universe by measuring how it's expanding and using Einstein's theory.

The fact that they all fit with the picture of a universe that's 13.8 billion years old, a sun that's 4.5 billion years old, a planet that's 4.5 billion years old, the fact that it all fits is quite an intricate model. And so you could say, well, I argue with the measurements of the age of the Earth. Maybe I don't like the radioactive dating or something, and people will say that.

The fact that they all fit with the picture of a universe that's 13.8 billion years old, a sun that's 4.5 billion years old, a planet that's 4.5 billion years old, the fact that it all fits is quite an intricate model. And so you could say, well, I argue with the measurements of the age of the Earth. Maybe I don't like the radioactive dating or something, and people will say that.