Galilean relativity rules! (At speeds much less than the speed of light)

The Mythbusters team looked at what happens when you fire a soccer ball at 50 mph backwards out of the back of a truck that is moving forward at 50 mph. The result would have come as no surprise to Galileo.

But if instead of a soccer ball, you fired a beam of light out of the back, it would still travel at the speed of light, however fast the truck was moving. (The truck can never travel at the speed of light, of course.) You would have to use the Lorentz transformations, not the Galilean ones, when you have objects traveling at close to or at the speed of light. You could use the Lorentz transformations for the soccer ball case also (since the GT are an approximation to the LT).

The ultimate gated community – in space

Now that we have people going to space just for the hell of it and if they can afford it, there are some plans to open a space hotel in the year 2027 in the form of a rotating wheel (a la 2001) to simulate gravity to about one-sixth of the Earth’s.

As the first of its kind, Voyager Station is slated to be a luxury resort designed to accommodate 280 guests and 112 crew members, complete with a restaurant, a bar, a concert hall, a gym and even a cinema.
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After blasting off from Earth, guests will arrive at a central, zero-gravity docking hub. From there, elevator shafts will carry them outward to a chain of “habitation modules” arranged around the circumference of the circular station. It’s only there, at the edge of the wheel, that the centrifugal force will be strong enough to keep guests and their surroundings firmly grounded.
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Wandering the 24 modules, which come in at 125,000 square feet total, they’ll find all the aforementioned amenities of this resort in the sky.
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On its website, the company urges potential clients to get in on the action: “Be one of the first humans to vacation on a luxury space station. Make history as one of the first humans in history to own real estate in orbit.” As if it were promoting any old property in Aspen or Palm Beach, the site advertises short- and long-term leases for “luxury villas, commercial, retail and industrial space” — pun perhaps intended. They’re already in negotiations with booking agents, Alatorre says.

Yes, finally the very wealthy will be really, really free of the presence of the hoi polloi, their ultimate dream.

If you want more information, you can check out the website.

While I can see this maybe becoming reality at some point, 2027 seems highly unlikely.

The dark matter problem

According to our current theories of physics, all the matter-energy in the universe consists of about 68.5% dark energy, 26.5% dark matter, and about 5% regular matter. The dark matter is believed to be around galaxies in a halo while dark energy is everywhere. The problem is that we have not so far been able to directly detect any dark matter particles despite strenuous and expensive efforts. After each failure to detect a signal, the debate is always whether to give up the search and declare that dark matter does not exist or to build a bigger, more sensitive detector with other materials in the hope that it will work. As I discuss in my book The Great Paradox of Science, this is a recurring situation in the history science. At any given time, in addition to the dominant paradigm, there are always other competing paradigms seeking to dethrone the champion. The fortunes of the competitors depend upon he fortunes of the dominant one and in the case of dark matter, competitors see an opening in the failure to detect it.
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Somber milestone

Yesterday saw the tally of global deaths from covid-19 pass the five million mark. This is a staggering number. The number of people who have been infected is close to 250 million, which is over 3% of the world’s population.

These are likely to be undercounts since they depend upon accurate diagnosis and reporting. We may have to wait for a more accurate count of deaths when they calculate the excess mortality. By comparing the number of deaths during the period of the pandemic and subtracting from it the number of people who died during a similar period before the pandemic, that will give us a different, and hopefully more accurate, estimate.

The difficulty of becoming sober in an alcohol-drenched society

I am someone who does not drink alcohol and never have, except for the very, very rare wine or beer or champagne on some special occasion. The taste just does not appeal to me and it has been very easy to rebuff the attempts of many people who have tried to persuade me that I should drink because they think I am missing something pleasurable or because it is the socially acceptable thing to do.

While I do not miss drinking, I am well aware that there is a whole world out there that I am not a part of and that is bar life. I experience that only vicariously because it is a staple of films. Going by films, it seems to be common for people to spend a lot of time in bars and clubs where drinking throughout the evening is the norm. For people for whom that is a major part of their world, quitting drinking can be difficult because it is not just the alcoholic buzz that they miss but the particular form of social life that goes with it.
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Supreme Court blocks religious vaccine exemption

The US Supreme Court yesterday refused to grant an injunction to stop the implementation of Maine’s requirement that nearly all health workers be vaccinated or lose their jobs.

Maine requires nearly all health care workers to be vaccinated against Covid-19. It argues that this requirement is necessary because those workers are unusually likely to interact with patients who are vulnerable to the disease, and because the state’s health care system could potentially be disabled if too many health care workers are infected. The state does exempt a very narrow slice of health care workers, however: those who risk adverse health consequences if they are vaccinated, such as people with serious allergies to the vaccine.

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Covid among older people

Being an old person myself, I am somewhat attuned to news items about how the pandemic is affecting that age cohort. It is well-documented that the virus has far more serious effects on older people and that the vaccine is their best bet to avoid serious illness and death. It is infuriating that so many older people have succumbed to the misinformation about the vaccines and not taken them.

David Leonhardt of the New York Times reviews the statistics. He says that while the number of cases and deaths are declining nationwide, it could have been much better among the older population.
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The long-term side effects issue

One of the lesser-publicized objections to taking the covid-19 vaccines is the fear that side effects may appear after many years. This is, on the surface, a more plausible cause of concern since the vaccines have been around for less than a year and we do not have any data on what effects it might have after periods longer than that. So it is not surprising that some people feel that the verdict is not yet in on long term safety.

But scientists say that this fear can be allayed by explaining how vaccines work. The fact that the vaccines provide immunity for long times, sometimes for life, is not because they stay in the body that long. After triggering the immune response and creating antibodies to the virus, they quickly degrade and go away.
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The murky ancestry of John James Audubon

I know nothing about birds but was of course aware of the name John James Audubon who became famous for his books containing detailed and lavish color paintings of the birds of America. His name has been adopted by various ornithological societies and one hears references to his name all the time. For some reason, I had thought that he was Black and was thus surprised when I read this news item that the Audubon Naturalist Society is dropping the name because of Audubon’s unsavory history and racist attitudes that, among other things, involved slave trading. They are making this move as part of a nationwide trend of not honoring people who have been guilty of deplorable acts.
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The most vaccinated region in the US is … Puerto Rico

Puerto Rico has become the most vaccinated region in the US and why that may be so is interesting.

Puerto Rico has fully vaccinated just over 73% of its 3.3 million residents, according to the US Centers for Disease Control and Prevention. That’s more than 2.3 million people.
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On the mainland, Vermont leads with 70.8% of the population fully vaccinated, followed by Connecticut at 70.2% and Maine at 70%, according to the CDC, which added that just over 57% of the total US population was fully vaccinated as of Friday.

Dr. Ashish Jha, dean of the Brown University School of Public Health, wrote on Twitter that Puerto Rico’s “fabulous” vaccination efforts have “gotten way too little attention.”
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