Quanta Magazine: “What is a Particle?”

Different representations of the Poincaré group are particles with different numbers of spin labels, or degrees of freedom that are affected by rotations. There are, for example, particles with three spin degrees of freedom. These particles rotate in the same way as familiar 3D objects. All matter particles, meanwhile, have two spin degrees of freedom, nicknamed “spin-up” and “spin-down”, which rotate differently. If you rotate an electron by 360 degrees, its state will be inverted, just as an arrow, when moved around a 2D Möbius strip, comes back around pointing the opposite way.

Elementary particles with one and five spin labels also appear in nature. Only a representation of the Poincaré group with four spin labels seems to be missing.

The correspondence between elementary particles and representations is so neat that some physicists — like Van Raamsdonk’s professor — equate them. Others see this as a conflation. The representation is not the particle; the representation is a way of describing certain properties of the particle, said Sheldon Glashow, a Nobel Prize-winning particle theorist and professor emeritus at Harvard University and Boston University. Let us not confuse the two.

Natalie Wolchover

Interesting article about the multitude of ways in which physicists are examining the concept of elementary particle. Nevertheless, my initial impression was that the central premise of the article, that physicists know so little about the answer to this fundamental question, is a bit contrived – as if either the scientists were trying to justify their continuing experiments by downplaying existing knowledge and overemphasizing remaining mysteries, or the author was doing something similar to be able to cover the topic again and again in the future.

Wired: “How Google alerted Californians to an Earthquake before it hit”

Here’s how it works: When an earthquake occurs, it sends softer seismic waves, known as P waves, through the ground. Not everyone in the earthquake’s area will feel these, but a network of 1,300 USGS sensors do. When four sensors are simultaneously triggered, they send an alert to a data processing center. If that data meets the right criteria, the ShakeAlert system determines that stronger S waves, the kind that can cause damage and hurt people, could be on the way. It’s then that warning systems, like Google’s, an app called MyShake, or government agencies like the Federal Emergency Management Agency and transit systems, will interpret the data and send out alerts.

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Google has also turned individual phones into miniature earthquake sensors. All smartphones have accelerometers that can pick up signals of an earthquake. If triggered, the phone sends the message to a detection server, along with rough location data, like the city a device is in. The server then pieces together where the earthquake is happening from data collected on multiple phones and beams out the relevant alerts.

Stogaitis says phones only pick up the waves when plugged in and locked. That helps to avoid confusion from phones jostling around in bags and pockets. The long-term goal is to send signals with even more speed. We’re looking at trying to make the time from which [an earthquake begins] and the time that we detect it and send an alert as fast as possible, says Stogaitis.

Amanda Hoover

Coincidentally there was an earthquake in Romania in the early hours of the morning today. I don’t usually sense earthquakes when I’m sound asleep, but this time I woke up despite its small magnitude. To my surprise, a push notification from Google was waiting for me on the phone and it reminded me of this article from a couple of days ago.

The Verge: “Microsoft Surface defined 10 years of Windows PCs — can it nail the next 10?”

Microsoft took a nearly $1 billion hit on Surface RT around six months after its launch because the company had simply built too many devices that it couldn’t sell. It was a near disaster for the entire Surface project.

Days after the news of the $1 billion write-down made headlines around the world, the Surface team of around 300 people was all standing in a lab they were still in the middle of building. Panay had called an all-hands meeting, and it was a tense moment for the team.

I just said, Everybody stand up and take a step forward. They did, we all did together, as a team, recounts Panay, his voice softening with emotion. I said, We have a plan, stay in the boat, keep rowing your oar. We’re going to get there. We have a plan, stick with it.

Tom Warren

The success of the Surface, dismissed by many at launch, is a testament to the value of steadiness, of having confidence in a product vision and improving the finished product with each iteration. A lesson other Silicon Valley companies could do well to learn, especially Google with their myriad of competing chat apps and constant resets of the Pixel smartphone line.

Custom number formats in Excel (and their pitfalls)

One of the more powerful Excel features that is relatively underused by most people – at least in my experience – is custom number formatting. It allows end users to change how numeric values are shown in the cell without changing the underlying data. This in turn enables Excel to perform calculations and link formulas to these cells, while at the same time displaying different information that better conveys its purpose.

Basic number formats are front and center in the Excel interface on the ‘Home’ tab, as they power the various options to change numbers to ‘Currency’, ‘Accounting’, ‘Percentage’, even ‘Scientific’ and ‘Date’ and ‘Time’. Ironically, I think this is partially the reason why the feature is somewhat obscure: people are using the basic version so frequently, they never think there’s a more advanced and powerful incarnation waiting to be discovered.

Follow Creators in Microsoft Edge

Continuing a string of various, more or less useful updates, Microsoft Edge has introduced the ability to follow creators directly in the browser. When vising creator profiles on supported sites, the browser temporarily shows a prompt in the address bar to ‘Follow’ said username; after the prompt fades, it leaves behind a permanent button to follow/unfollow next to the Favorites star. By default you will receive notifications whenever these creators post new content via a popup next to the Collections button. From this popup you can navigate to the new post, snooze the notification, or manage these updates in a separate sidebar. The browser also added two new settings entries to control the feature, available in the section ‘Privacy, search, and services’: here you can enable or disable both the notifications and the address bar prompts to follow new creators.

The Economist: “Europeans should welcome Russian draft-dodgers”

The struggle for Russian hearts and minds is one that must be waged primarily by Russians themselves. Mr Putin is attempting to rally support with the argument that the entire West is fighting Russia, and that it holds Russians in contempt and wants to destroy their country. The West counters that its argument is with Mr Putin and his regime, not the Russian people. It does not want the destruction of Russia, but for Mr Putin to leave Ukraine to determine its own future as a sovereign nation.

If Europe shuts its borders to all Russians, it is handing Mr Putin tangible evidence that he is right. It undermines Europe’s credibility as a defender of human rights and alienates those parts of Russian society whose interests and values are most strongly aligned with the European Union and Ukraine. It is also failing to shelter the people best suited to rebuild the Russian state once he is gone. Just as it did in the cold war, the West should offer safe haven to the Russians with whom it has no argument.

If the exodus of draftable Russians continues, Mr Putin may decide to impose his own travel ban on them. In other words, the man who called the collapse of the Soviet Union the “greatest geopolitical catastrophe” of the 20th century may partly recreate the Iron Curtain. Now, as then, the West should let the tyrant in Moscow take the blame for restricting Russians’ freedom, and welcome the brave souls who escape.

The Economist

The recent mobilization orders in Russia have sparked another round of furious debate, this time over the rising numbers of Russians fleeing the country to avoid being drafted. European countries bordering Russia have rushed to close their borders and prevent their entry. As many, including the article above, pointed out, a blanket ban against Russian citizens is against Schengen rules and violates the right to asylum, has little strategic justification, and fuels Putin’s narrative that the West is targeting Russians as a whole, rather than Putin’s regime specifically.

The Spectator World: “Are sanctions against Russia actually working?”

Sanctions, however, shouldn’t be judged solely on the amount of damage they do a targeted economy. The principal objective of economic pressure isn’t to punish a nation for atrocious behavior, bankrupt a country’s finances, or register disapproval about an adversary’s foreign policy — it’s to push a country’s political leadership into changing its behavior in a more positive direction. In the case of Russia, this means compelling Putin to end his aggression in Ukraine, either by withdrawing his forces from the country or entering into serious peace negotiations with Kyiv.

Needless to say, neither of those objectives have been accomplished — and it’s increasingly difficult to envision Putin simply throwing up his hands and suing for peace, particularly at the hands of Western economic pressure. Indeed, Putin appears to be as committed to his military and political objectives in Ukraine today as he was when he ordered the invasion last winter. Putin, at least as of this writing, appears to have made the calculation that succeeding in a war of choice (or at least not failing) that is now inextricably tied to his personal legacy is worth enduring long-term structural weaknesses in the Russian economy.

Daniel DePetris

A slightly older piece, but the central argument remains valid. Since then, Putin has demonstrated his commitment to sustained war by calling for a partial mobilization, running referenda to incorporate four occupied regions of Ukraine, and making renewed threats to use nuclear weapons to defend this new ‘Russian’ territory. None of this signals a willingness to back down or accept diplomatic talks. The rapid advancement of Ukrainian troops in the occupied territories should change Putin’s calculus somewhat – but for the moment it has only let to more hardening of his position.