That excellent comedy show That Mitchell and Webb produced this sketch.
It turned out that this sketch inspired some researchers to investigate whether rocket scientists and brain surgeons were smarter in general than other people. The answer is no.
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How do you tell if you are in an inertial frame or not? According to Newton’s model of a fixed space, an inertial frame is one which is at rest or moving with constant velocity through that fixed space. We saw that determining this required us to observe the state of motion through that space of an object Q that was known to be not under the influence of any forces. If you observe Q to be at rest or moving with constant velocity, then you are in an inertial frame. If however, even in the absence of forces, the freely floating object Q appears to be accelerating in some direction with respect to you, you could conclude that this must be because you are in a frame that is an accelerating in a straight line in the opposite direction and hence you are not in an inertial frame.
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We live in an era when people have the opportunity to broadcast the minutiae of their lives far and wide via social media. It is surprising to me that so many people do not seem to realize that along with the attention they receive, there are also serious pitfalls. In the rush to be in the spotlight and impress their circle of friends and relatives, they seem to lose all sense of judgment. Nowhere was this more evidence on a large scale than in how so many of the people who invaded the Capitol building on January were eager to tell everyone of their exploits.
First of all, they gave the authorities information about their identities that allowed them to be arrested. Secondly, their online posts were effectively confessions of guilt. The best they could hope for was leniency on the grounds that they were too stupid to know that they were breaking the law. But judges are taking their posts into account in determining how harshly to sentence them and they are not amused.
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The state legislature in Texas developed a too-clever-by-half law to effectively circumvent the constitutional right to abortion as determined in the 1973 US Supreme Court ruling Roe v. Wade. It said that the state would not enforce the law but allowed ordinary citizens to sue abortion provides and offered them with a $10,000 bounty for doing so. Last week, the US Supreme Court refused to issue a stay of the Texas law while the review process was underway but did allow abortion providers to sue certain Texas officials.
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As a computational matter, when we are in a rotating frame such as the Earth, we have a choice. We could work with inertial frames where Newton’s laws and Maxwell’s equation are valid, use real forces only, and make sure to include all the accelerations introduced due to the rotational motions. Or we could use a frame that is embedded in the Earth and thus rotating but treat it as an inertial frame by including via the fictitious Coriolis and centrifugal forces the non-inertial effects caused by its rotation. The two methods are mathematically equivalent but conceptually different. It is sometimes easier to treat the Earth as an inertial frame that is not spinning and incorporate fictitious forces and that is often done in the field of meteorology.
It is the search for genuine inertial frames that is of interest in this series of posts because it is important in the resolution of the radiation paradoxes.
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One of the appalling things about the current pandemic is the great inequality in vaccine availability around the globe, highlighting once more how the wealthy nations are able to corner the market on valuable resources. In this case, since many of the companies that are the biggest producers of vaccines are private ones and they seek to make as much money as they can, they have entered into contracts to mostly supply wealthy nations like the US that are able to pay more, while the WHO consortium that sought to provide vaccines to poorer countries through its COVAX program has found it hard to get adequate supplies.
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In trying to understand and resolve the paradox I wrote about in the first post in this series, I will be taking a somewhat circuitous route in order to lay some important groundwork before we can directly confront the paradox.
We can start the journey by looking at one of the most fundamental concepts in physics, that of the nature of space. On the surface, space seems like a very straightforward concept. It is seen as a kind of container in which everything in the universe exists. But difficulties arise when one asks questions such as whether space can be viewed as something positive, a tangible entity that has its own properties that can be detected, or whether it is viewed as something negative, that signifies the absence of matter in a region. Another way of posing the distinction is asking whether, if one can conceive of removing all the matter and energy in the universe, what would we be left with? Just ’empty space’? In the absence of matter, would such a thing have any meaning at all?
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The concept of ‘wellness’ has been gaining ground in the US. It is a vague term and, as I understand it, it means taking proactive steps to maintain one’s health, such as eating healthily, getting exercise, avoiding harmful practices like smoking, getting enough rest, and so forth. The idea is that by doing so, one can stave off some of the ailments and illnesses that can affect one’s wellbeing.
An additional layer is laid on in the name of holistic’ approaches to health, with the idea that the mind and body are connected and that one should also try and maintain a healthy mindset. These could include practices like yoga, meditation, relaxation techniques, and other activities that seek to reduce stress, blood pressure, and the like.
All that is perfectly reasonable.
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I have written before that many of the followers of Donald Trump seem to resemble members of cults. While these cult members seem to be easily persuaded to believe the most bizarre things and even to commit reckless and pointless acts of defiance such as invading and vandalizing the Capitol building on January 6th, they do not seem (at least so far) to exhibit the more extreme forms of cult behavior, such as being willing to take actions on the command of their leader that could lead to their own deaths. One the most extreme examples of such cult behavior was the Jonestown massacre in Guyana where in 1978 over 900 people died, many of them because they took cyanide poison on the command of their leader Jim Jones, that he ordered after his guards killed a visiting US congressman and four of his entourage.
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I have recently fallen down a rabbit hole in physics trying to resolve some paradoxes that I stumbled upon. In spending a lot of time and mental effort trying to understand what is going on, I realized that although I have spent my life studying and teaching physics, I did not fully understand some very fundamental aspects of space and motion and the way that the laws of physics operate. That is part of the fascination that physics provides, that it can always surprise you, leading you to learn new things.
In an occasional series of posts, I will share with readers my journey through this maze, trying to make things as clear as possible to the non-physicists out there. This will not be easy because an important prerequisite to explaining something to someone else is for you to understand it first. I cannot claim to understand completely what I am going to be writing about, for which I apologize in advance. But it is well known among teachers that it is in trying to explain something to someone else that one starts more deeply understanding what one is trying to say. Like many teachers I have used students as sounding boards for tentative ideas.
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