Radiation paradoxes 7: Accelerating frames and the general theory of relativity

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

At this point, we need to take a slight detour and examine more closely the role of accelerating frames because that is central to resolving the paradox that started this series if posts, of whether an electric charge falling freely under gravity radiates or not. The discussion up to this point has seemed to privilege inertial frames when it came to discussing the laws of physics. This was because we knew how to transform physical quantities between any two inertial frames, using Galilean transformations for Newtonian motion at low speeds and Lorentz transformations when we needed more accurate results or were dealing with speeds comparable to that of light in the regime of special relativity. But transforming between inertial frames and accelerating ones was another story.

Einstein used the insight that any two masses will fall at the same rate in a gravitational field to argue that the distinction between inertial frames (where the laws of physics such as Maxwell’s equations are supposedly valid) and non-inertial frames (where they are not) should not matter and that we should be able to find transformational relations between them.
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Desmond Tutu represented the best of religion

The indefatigable South African fighter for human rights died today at the age of 90.

His achievements are well known and the many, many obituaries and articles that will be written in the next few days will review them. What I liked best about him was that he used his eminence to speak out boldly, not caring about taking on sacred cows or tribal allegiances. He criticized the ANC after they took power, for which they retaliated by initially not inviting him to nelson Mandela’s funeral. He was one of the earliest major figures to label Israel as an apartheid state. That carried immense weight since who would know better than he what apartheid looked like? That outspokenness did not endear him to the apologists for Israel and it is suggestive that the Guardian article linked to above or the obituary does not even mention that particular stance of his, highly impactful though it was.

On a personal note, my daughter and son-in-law visited South Africa for a college friend’s wedding at which Tutu was to officiate. At an informal lunch, they met him. He was wearing a Morehouse College t-shirt and they said that he was playful and mischievous, joking around. I have a photograph of just the three of them and you can see the wide grin and the twinkle in his eyes. He was clearly someone who was serious about his work but did not take himself too seriously. He is the kind of person that one would enjoy just hanging out with.

Tutu clearly was a religious person, the kind who believes that his faith requires him to fight for justice for all. That is the best kind of religion.

Seeing the universe in its infancy

Yesterday NASA’s James Webb Space Telescope was successfully launched into space from French Guiana, using the European Space Agency’s Ariane 5 rocket. If all goes well, within the next year we will be seeing images of when the universe was in its infancy.

Here is a quick overview of the telescope.

The launch is just the first stage of a very complex journey in which engineers have said that there are many delicate steps that need to go right and the failure of any one could ruin the mission.The telescope is a truly extraordinary piece of engineering design.

The James Webb – named after a former Nasa administrator – will spend a month on its journey and will then need a further five months to get ready. First, its enormous gold-plated 6.5 metre mirror and its huge, tennis-court-sized sunshield need to unfurl; they were folded origami-style to fit into the nose cone of the Ariane 5. Then its instruments will have to be carefully calibrated. In all, hundreds of release mechanisms need to work perfectly in order for the telescope to succeed.

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Jesse Watters may be stupid and juvenile but he is dangerous

Fox News personality Jesse Watters has a juvenile sense of humor that he should long have outgrown. He is the kind of grown person who still thinks that childish pranks are funny.

At a gathering of young right-wingers organized by the group Turning Point, he took aim at Anthony Fauci, the highly respected infectious disease specialist who has become a prime target of anti-vaxxers because of his relentless urging of people to take safety precautions such as getting vaccinated, wearing masks, and avoiding large gatherings.

Speaking on Monday at Turning Point USA’s AmericaFest conference, Watters encouraged attendees to rhetorically “ambush” Fauci with dubious questions about the National Institutes of Health allegedly funding “gain-of-function” research at the Wuhan Institute of Virology.

“Now you go in for the kill shot. The kill shot? With an ambush? Deadly. Because he doesn’t see it coming,” Watters said.

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The growing divide within the American evangelical movement

CBSN looks at the growing split within the evangelical movement between those who take extreme ideological stances and those who try to provide a more unifying message.

Vice News looked at the rise of evangelical churches that echo the conspiracy theories of Q. This has alarmed some evangelical leaders who see this as a dangerous trend. One of them said that it used to be that evangelicals looked for churches that reflected their theology and beliefs about God. But he says that now some are looking for churches that reflect their political ideology. They want to hear their political views affirmed from the pulpit and this has given an opening to some preachers who are willing to go all in on extremist views and thus garner followers.

One thing that immediately strikes you when the camera pans over the congregations of these extreme churches is that they are almost exclusively white.

Another thing is that at one of the churches that is heavily featured in both clips, there is not a mask to be seen in the crowded tent where about a thousand people crowd together to hear the pastor say that he will throw out anyone who wears one. They are practically begging to be an Omicron superspreader source.

Such reckless behavior truly boggles the mind.

Radiation paradoxes 6: Getting rid of gravity

(Previous posts in this series: Part 1, Part 2, Part 3, Part 4, Part 5)

The fact that all masses accelerate at the same rate when subjected to purely gravitational forces but do not do so for any other type of force indicates the singular nature of gravity. Another peculiarity of gravity is that although we can shield bodies from the effects of other forces, we cannot shield them from gravitational forces. Although the concept of gravity has been around for a long time and we have used it to explain so much, from the motion of planets to terrestrial events, gravity remains a somewhat mysterious force, difficult to incorporate into more general schemes. Attempts to create unified theories of all the forces have been foiled by gravity. Trying to unify quantum mechanics with gravity has also proven to be extremely difficult, resisting the most determined efforts from some the best minds in physics, including Einstein. This is partly because gravity, unlike electric and magnetic forces, is a non-linear force and non-linear forces are notoriously difficult to handle mathematically.
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The variable rate of the Earth’s rotation

Recall how in one of my recent posts on the radiation paradoxes, I spoke about how you can measure the spinning rate of the Earth by looking at the stars and also by measurements taken purely on the Earth and that these two methods produce results that are remarkably close. This was used in support of the claim by Bishop Berkeley that it was the stars that exerted a dynamical influence on the Earth and that our motion was relative to, not space itself as Newton thought, which he felt was an unobservable entity and thus had no relevance.

The rate at which the Earth is spinning on its axis is not fixed though. Over time it has been slowing down, meaning that the days have been getting longer. Around 600 million years ago, the day was about 21 of our present hours. But a new wrinkle appeared in the last half century in that the rate of rotation was increasing slightly and this caused problems. As our ability to measure time became more accurate with the adoption of atomic clocks, this required the regular adoption of the so-called ‘leap second’, which was a second added to clocks to bring them back into sync with the time as measured with respect to the stars.
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The reactionaries are in decline, not ascendant

It is easy to feel a sense of despair at the news these days. The coronavirus seems to once again have defied predictions and infections are on the rise with the new omicron variant. We have ignorant but influential people still discouraging people from taking vaccines that could save their lives. We have a Republican senate, aided by Democratic senators Joe Manchin and Kyrsten Sinema block legislation that would improve the lives of so many people. And we have a US Supreme Court seemingly poised to roll back the right to an abortion and otherwise advance a reactionary right wing agenda.

Rebecca Solnit is one of the most thoughtful writers and analysts and she has come out with an opinion piece that suggests that what we are witnessing is not the rise of a major reactionary movement but the dying gasps of a desperate minority waging a bitter rearguard battle against historical forces that they realize are going to overwhelm them and take away the power they have held for so long.
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