Author: The Conversation

South Africa has experienced power shortages with rolling blackouts on an unprecedented scale in 2022. This state of affairs is largely due to technical failures at its ageing fleet of coal power plants. The present power generation shortage is due to the power utility Eskom’s failure to add sufficient new electricity generation to the grid. This meant that it had to keep ailing old power stations going beyond their projected life span. The coal plants are prone to frequent renewed breakdown. In addition, their maintenance and parts replacements are becoming prohibitively expensive. Given the major contribution that the burning of coal makes to greenhouse…

Everything in the universe has gravity – and feels it too. Yet this most common of all fundamental forces is also the one that presents the biggest challenges to physicists. Albert Einstein’s theory of general relativity has been remarkably successful in describing the gravity of stars and planets, but it doesn’t seem to apply perfectly on all scales. General relativity has passed many years of observational tests, from Eddington’s measurement of the deflection of starlight by the Sun in 1919 to the recent detection of gravitational waves. However, gaps in our understanding start to appear when we try to apply it to extremely small distances,…

One hundred years ago, our understanding of ancient Egypt changed forever when the tomb of King Tutankhamun was found on November 4, 1922 in the Valley of Kings. Born around 1305BC, Tutankhamun only ruled Egypt for about ten years. Yet his tomb was furnished with never-before-seen riches. Our fascination with mummies is understandable. Gazing on the face of a prehistoric Egyptian king makes these ethereal and majestic rulers seem more real. The discovery of Tutankhamun in his original resting place, complete with all his possessions, makes us feel a connection to a primeval past. It transports us back in time to the funeral of a…

It’s pretty normal to walk through a university campus and see students sitting together, yet ignoring each other for their smartphones – but not in Spain. I’m currently visiting the University of Navarra, where each time I pass the open space outside the Institute for Culture and Society, I see the vast majority of students talking to each other without their phones in hand. As Inés Olza, a linguist from the institute, explains: In Spain people like to talk. For them, a conversation is a cooperative process; silence makes them uncomfortable. This is great news for these students, because ignoring people…

There’s an awkward, irksome problem with our understanding of nature’s laws which physicists have been trying to explain for decades. It’s about electromagnetism, the law of how atoms and light interact, which explains everything from why you don’t fall through the floor to why the sky is blue. Our theory of electromagnetism is arguably the best physical theory humans have ever made – but it has no answer for why electromagnetism is as strong as it is. Only experiments can tell you electromagnetism’s strength, which is measured by a number called α (aka alpha, or the fine-structure constant). The American physicist…

Not long ago, FTX was one of the world’s largest trading platforms for cryptocurrencies. Founded in 2019, the Bahamas-based crypto exchange had a meteoric rise to prominence, and was valued at more than US$30 billion earlier this year. All that has changed in the past two weeks. First, concerns emerged about links between FTX and an asset-trading firm called Alameda Research, including suggestions that customers’ funds have been transferred from FTX to Alameda. A few days later, rival firm Binance (the biggest crypto exchange) announced it would sell its holdings of FTT tokens, a crypto that reportedly comprises much of Alameda’s assets. Panicked customers rushed to withdraw funds from FTX, and…

Wearable devices that can record your pulse can be handy for tracking your fitness – but can you really use them to monitor for an irregular heartbeat? The short answer is maybe, and it depends on who you are. These devices are great, but there are some things you need to know. Several large studies have been carried out to examine how well wearables can check for signs of a common heart rhythm problem called “atrial fibrillation”, which can lead to strokes. In a new Frontiers review published in Circulation, we and our colleagues in the AF-Screen International Collaboration weighed up the current…

In the second season of BBC mystery thriller The Capture, deepfakes threaten the future of democracy and UK national security. In a dystopia set in present day London, hackers use AI to insert these highly realistic false images and videos of people into live news broadcasts to destroy the careers of politicians. But my team’s research has shown how difficult it is to create convincing deepfakes in reality. In fact, technology and creative professionals have started collaborating on solutions to help people spot bogus videos of politicians and celebrities. We stand a decent chance of staying one step ahead of fraudsters.…

Here are two common ways of thinking about democracy in the online era. First, the internet is a liberation technology and will usher in an era of global democracy. Second, you can have social media or democracy, but not both. Which is more correct? There is no doubt democracy is in retreat around the globe. Even supposedly stable democracies have recently seen events incompatible with democracy and the rule of law, such as the violent assault on the US Capitol in 2021. To understand the role of social media in this process, we carried out a systematic review of the evidence linking social media to ten indicators…

In the wake of Elon Musk closing the deal to buy Twitter on October 27 and soon after firing the management, users have been reconsidering the platform. Hashtags #TwitterMigration and #TwitterExodus are gaining popularity, and the most common name found in conjunction with it is Mastodon – the new home for fleeing tweeters. In fact, Mastodon is not that new. It was launched in October 2016 by German software developer Eugen Rochko, spurred on by his dissatisfaction with Twitter and his concerns over the platform’s centralised control. After its 15 minutes of fame in early 2017, Mastodon’s growth slowed to a crawl. Now, it’s on the upswing again – more…