I'm just going to address the question of the constancy of the constants of nature.
His first example was that of the speed of light. Speed is defined as the distance traveled divided by the time it takes to travel that far. So, we have two questions: how do we define distance? And how do we define time? Well, it turns out that the definitions of *both* of these change over time. Early on in this century we primarily used mechanical clocks to measure time. These have a very limited accuracy, which means that different clocks will measure different time intervals and the same clock will do so at different times. So, while the second was defined as a certain fraction of the year 1900, this simply wasn't an accessible standard for making sure different clocks kept the same time.
Later, we started getting quartz clocks, which are much more accurate, although still have issues with synchronization between different clocks. This lead to more accuracy in our measurements of the speed of light. We should also appreciate the sensitivity of these measurements. We are trying to measure accurately the distance light travels in a fixed period of time. Well, light is moving at over 186,000 miles per second (even with the variations claimed). If your clock is only accurate to 1 millisecond, then you expect to be off by 186 miles per second or so. Alternatively, if you are measuring in a lab, you are talking about times on the order of nanoseconds to microseconds and you have to measure them to within one part in 10000. Not such an easy thing to do.
But, it is possible to determine the *constancy* of a constant much more accurately than we can determine the *value* of that constant in many cases. The easiest to show is the gravitational constant. if it varied in the way proposed, this would have very obvious effects on the orbits of satellites. We don't see such effects, so G certainly doesn't vary nearly as much as is claimed here. We don't need to know the value accurately to know whether it is changing at the level of 1 part in 10,000 over time.
Now, the definitions sof the 'meter', the 'second' and the 'kilogram' have actually changed over time. At the turn of the 1900s, the meter was defined as the distance between two marks on a bar kept in Paris. All other distance measurements had to use that as a reference. You can imagine the difficulties of making sure everything across the world kept to that standard. Similarly, the second was defined as a certain fraction of the year 1900. That was hardly an accessible standard for calibrating a clock.
So we have an issue that the very definitions of our measurements can potentially vary. So, even if the speed is 'constant', the actual numbers can vary. An easy example is a car that is moving at 60 mph that is also going 100kph. The numbers look different, but the speed is the same.
So, how to fix this? One is to get a standard that is relatively easy to check in labs around the world. The other is to find 'constants' that do not depend on the definitions of the meter, second, or kilogram.
The second is the more interesting one: there are numbers we can compute that are 'dimensionless' and so will be the same no matter how meters or seconds or kilograms are defined. One of these is the fine structure constant. And yes, we can and do investigate whether these constants change over time, whether they fluctuate, etc.
But yes, the speed of light is now a defined quantity as part of our definition of the meter. So the question today isn't whether the speed of light changes, but whether the length of a meter changes. And, again, if there were significant changes, those would be obvious from other effects.
Now, people do consider whether these dimensionless constants change over time. There was even a suggestion a few years ago that the fine structure constant was slightly different in the early universe. That wasn't supported by later evidence, but the question of whether basic constants change has been and continues to be addressed. But, at this point, no measurements support such changes.
So, this guy is wrong in several ways. he ignores how our definitions have changed over time. He ignores that we *do* investigate how these constants change. And he doesn't seem to grasp the role of dimensionless constants in this discussion.
His first example was that of the speed of light. Speed is defined as the distance traveled divided by the time it takes to travel that far. So, we have two questions: how do we define distance? And how do we define time? Well, it turns out that the definitions of *both* of these change over time. Early on in this century we primarily used mechanical clocks to measure time. These have a very limited accuracy, which means that different clocks will measure different time intervals and the same clock will do so at different times. So, while the second was defined as a certain fraction of the year 1900, this simply wasn't an accessible standard for making sure different clocks kept the same time.
Later, we started getting quartz clocks, which are much more accurate, although still have issues with synchronization between different clocks. This lead to more accuracy in our measurements of the speed of light. We should also appreciate the sensitivity of these measurements. We are trying to measure accurately the distance light travels in a fixed period of time. Well, light is moving at over 186,000 miles per second (even with the variations claimed). If your clock is only accurate to 1 millisecond, then you expect to be off by 186 miles per second or so. Alternatively, if you are measuring in a lab, you are talking about times on the order of nanoseconds to microseconds and you have to measure them to within one part in 10000. Not such an easy thing to do.
But, it is possible to determine the *constancy* of a constant much more accurately than we can determine the *value* of that constant in many cases. The easiest to show is the gravitational constant. if it varied in the way proposed, this would have very obvious effects on the orbits of satellites. We don't see such effects, so G certainly doesn't vary nearly as much as is claimed here. We don't need to know the value accurately to know whether it is changing at the level of 1 part in 10,000 over time.
Now, the definitions sof the 'meter', the 'second' and the 'kilogram' have actually changed over time. At the turn of the 1900s, the meter was defined as the distance between two marks on a bar kept in Paris. All other distance measurements had to use that as a reference. You can imagine the difficulties of making sure everything across the world kept to that standard. Similarly, the second was defined as a certain fraction of the year 1900. That was hardly an accessible standard for calibrating a clock.
So we have an issue that the very definitions of our measurements can potentially vary. So, even if the speed is 'constant', the actual numbers can vary. An easy example is a car that is moving at 60 mph that is also going 100kph. The numbers look different, but the speed is the same.
So, how to fix this? One is to get a standard that is relatively easy to check in labs around the world. The other is to find 'constants' that do not depend on the definitions of the meter, second, or kilogram.
The second is the more interesting one: there are numbers we can compute that are 'dimensionless' and so will be the same no matter how meters or seconds or kilograms are defined. One of these is the fine structure constant. And yes, we can and do investigate whether these constants change over time, whether they fluctuate, etc.
But yes, the speed of light is now a defined quantity as part of our definition of the meter. So the question today isn't whether the speed of light changes, but whether the length of a meter changes. And, again, if there were significant changes, those would be obvious from other effects.
Now, people do consider whether these dimensionless constants change over time. There was even a suggestion a few years ago that the fine structure constant was slightly different in the early universe. That wasn't supported by later evidence, but the question of whether basic constants change has been and continues to be addressed. But, at this point, no measurements support such changes.
So, this guy is wrong in several ways. he ignores how our definitions have changed over time. He ignores that we *do* investigate how these constants change. And he doesn't seem to grasp the role of dimensionless constants in this discussion.
