People in the US complain a lot about about the restrictions imposed by the pandemic but they should see what Hong Kong has. This report is from a ProPublica reporter who is a Hong Kong citizen about what she had to go through in order to enter the country, starting with a very restrictive 21-day quarantine in a hotel at her own expense, even though she was vaccinated.

Incoming travelers were greeted by gowned, gloved and masked workers, who directed us through the terminal. As I followed the passengers ahead of me, I was unnerved by the shuttered stores….The terminal was now eerily still. My feet made too much noise as I trudged along the path marked by guardrails.
…

A PPE-covered worker sent me to a series of stations. First, I pulled my mask down for a nurse to swab my nose and throat for a PCR test. Then I presented my documents — preflight negative COVID-19 test, proof of hotel booking, Hong Kong resident ID and vaccination card — to an officer who scrutinized them before declaring me up to par.
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On Monday, the US recorded over a million new covid-19 cases, a new record, largely driven by the Omicron variant, and we may have not yet reached the peak, which is expected to be reached around mid-January. That statistic is a bit misleading since it includes corrections for delays in reporting over the holidays. In general, I do not pay attention to the daily numbers but instead focus on the averages taken over seven days. But that too has reached a record level of around 575,000, easily surpassing the previous high of around 250,000 set back on January 11, 2021.

Given this grim news, it may be hard to find a silver lining but there is one in that the death and hospitalization rates have not kept pace with the rise in case rates, even allowing for the usual two-week lag. The seven-day average of the death rate is currently around 1,200, compared to its previous peak of 3,400 a year ago. That may be an indication that Omicron is the first phase of the virus transitioning to an endemic, flu-like virus of the kind that we are accustomed to. Some indications of this are that the earlier symptoms of Covid-19, such as loss of a sense of smell and taste and low blood oxygen levels, are no longer as common with the new variant. It also appears that Omicron affects the upper respiratory tract more and is less like to affect the lungs.
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The annual Monterey Skepticamp is being held on Saturday, January 8th from 9:46am to 5:46pm California time. I will be giving a talk at 2:30pm.

Title: Why the age of the Earth has oscillated wildly over time

Summary: The age of the Earth seems to be a settled question in the scientific community, But estimates of its age have oscillated wildly in the past, starting with it being considered really old (even infinitely old) to becoming very young (of the order of thousands of years) to becoming sort of old (hundreds of millions of years) to younger again (tens of millions of years) to the current view of it being really old (of the order of billions of years). This talk will look at the interplay of scientific and religious thinking that was driving this fluctuation.

You can see the full schedule of speakers here.

It is free. You can RSVP here.

The Zoom link to join is https://us02web.zoom.us/j/88526995782

(Previous posts in this series: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8, Part 9)

In the previous post, I quoted Fritz Rohrlich who said that asking whether an accelerated charge really radiates is meaningless and that we need to also look at the value of the Poynting vector at the location of the detector. In discussing the radiation from an electric charge that is freely falling in a gravitational field, the state of motion of the charge and the detector both have to be taken into account. and this requires transformations between frames and will depend on whether the detector is an inertial observer or not. The transformations to accelerating frames requires the use of the mathematical machinery of general relativity.

With that. in mind, let us consider a charge Q and a radiation detector D and see what happens under various scenarios that describe different states of motion of each. There are five possible scenarios of interest to consider. It should be borne in mind that these scenarios are hard to test experimentally and, as far as I am aware, have not been tested.
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We have people who are opposed to vaccinations on ideological grounds, on partisan political grounds, on religious grounds, and who think that it undermines their ‘wellness’ attitude to health and believe that various dietary and mental therapies are the key to avoiding the disease and that vaccines interfere with that protection.

But there are those who do not fit into any of those categories and say that they are not opposed to vaccines as such but don’t get vaccinated because they think that vaccines are unnecessary if one lives a healthy lifestyle and do not have the comorbidities that make one a risk for serious illness and death, such as age or being immunosuppressed or having lung ailments. Younger and otherwise healthy people are likely to fall into this category of the unvaccinated.
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As long-time readers may have noticed, when it comes to complicated issues, as in the case of the current series on radiation paradoxes, I tend to post about it in installments. I have had many, many ten-to-twenty-or-more part series dealing with important questions, such as the Higgs, evolution, and the Big Bang. This doling out in small portions may be irksome to some, especially those who already know quite a bit about the subject, who may be impatient at my slow pace. They may wonder why I do not write out the entire thing first and post it in one long entry so that everything is settled once and for all.

There are several reasons for this. One is purely pedagogical. I think that it is hard to digest a lot of new and difficult material in one gulp. With small doses, where each post focuses on just one or more important issue, people can think and reflect on it, ask questions, and get things clarified in their own minds as best as possible and are thus more ready to move on to the next installment.
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(Previous posts in this series: Part 1, Part 2, Part 3, Part 4, Part 5, Part 6, Part 7, Part 8)

We saw in the previous post how Einstein’s Principle of Equivalence explained why two masses dropped from the same height in a gravitational field will fall at the same rate and hit the ground at the same time. It also seemed to resolve the paradox about whether an electric charge will fall more slowly than a neutral particle in a gravitational field. The answer arrived at was ‘no’ because since according to the PoE, the situation with the falling accelerating charge in the frame of the Earth E was equivalent to the charge being stationary in the inertial frame of space S, the charge would not radiate energy, contrary to naive expectations that any accelerating charge would radiate. On the surface, that seems to resolve the paradox that started this series of posts. The price we have paid is that we must abandon Postulate #2 and conclude that accelerating charges do not radiate when falling freely in a gravitational field.
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The Webb telescope team reported that a major step had been successfully completed on schedule. The telescope was launched on December 24th and all its components had to be folded into a small space to fit into the rocket nose cone and then opened up once it was in space, After seven days, the schedule called for the five-layered tennis court-sized silvery heat shield to be opened up and it did so.

The shiny silver shield measures 69.5 feet long by 46.5 feet wide (21.2 by 14.2 meters) when fully deployed — far too large to fit inside the protective payload fairing of any currently operational rocket. So it was designed to launch in a highly compact configuration and then unfold once Webb got to space.

That deployment is an elaborate, multistep process with many different potential failure points that could sink the entire mission.

“Webb’s sunshield assembly includes 140 release mechanisms, approximately 70 hinge assemblies, eight deployment motors, bearings, springs, gears, about 400 pulleys and 90 cables totaling 1,312 feet [400 m],” Webb spacecraft systems engineer Krystal Puga, who works at Northrop Grumman, the prime contractor for the mission, said in a video about Webb’s deployments that NASA posted in October.

Over the next six days, the rest of the telescope will get unfolded, starting in three days with the deployment of the secondary mirror support structure. And then it heads to its destination, the second Lagrange point which it should reach after 29 days.

You can see the sequence of steps in this short video.

It is a truly remarkable piece of engineering.