Physicists prove long-held theory light can be made from nothingness of vacuum
Oxford University physicists ran simulations to test how intense laser beams alter vacuum, a state once thought to be empty but predicted by quantum physics to be full of fleeting, temporary particle pairs.
Classical physics predicts that light beams pass through each other undisturbed. But quantum mechanics holds that even what we know as vacuum is always brimming with fleeting particles, which pop in and out of existence, causing light to be scattered.
The latest simulations, detailed in a study published in Communications Physics, recreated a strange phenomenon predicted by quantum physics.
The theory predicts that the combined effect of three focused laser pulses can alter virtual particles in vacuum, generating a fourth laser beam in a 'light from darkness' process. 'This is not just an academic curiosity,' study co-author Peter Norreys said. 'It is a major step towards experimental confirmation of quantum effects that until now have been mostly theoretical.'
Physicists used a simulation software package called OSIRIS to model interactions between laser beams and matter, giving them a peek into vacuum-light interactions that were previously out of reach.
The simulations revealed that intense laser beams could agitate virtual particles and cause light particles to scatter off one another like billiard balls.
They also showed how real-world factors such as imperfect beam alignment could influence the result. 'By applying our model to a three-beam scattering experiment, we were able to capture the full range of quantum signatures, along with detailed insights into the interaction region and key time scales,' said Zixin Zhang, another author of the new study.
Physicists now hope to conduct real-world laser experiments to confirm the bizarre quantum phenomenon.
The simulation experiment could also pave the way for more in-depth study of a range of theorised quantum effects in vacuum in other laser setups.
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The Sun
6 hours ago
- The Sun
The 6 facts every woman should know about their body – and it could save your life
From puberty to menopause, and everything in between, women's bodies go through a lot. We might know the fundamentals – what a vagina is, what a vulva does and how babies are made – but with the help of dozens of medical experts, journalist Polly Vernon has created an encyclopaedic deep-dive into female biology, from the very basics to the weird and wonderful. The truth is, women have been set up to feel like strangers in their own bodies, thanks to a lack of scientific research. 'Women's bodies were excluded from US clinical trials between 1977 and 1993,' Polly explains. 'For years, we were treated as smaller, stranger versions of men.' The consequences of this oversight have sent ripples into the success of diagnoses and treatment. 'Take mammograms: if it were men's testicles, would they be squashed flat like that?' Polly asks. 'Or smear tests – surely there's a better option than a speculum?' But there are glimmers of change. A DIY cervical cancer test that only requires women to take a swab at home will finally be rolled out on the NHS from January, and for the first time, there are now more female than male doctors in the UK. 'We're nowhere near where we need to be, but things are moving forward,' Polly agrees. Her book, How The Female Body Works, is a call to action for all women to reclaim, understand and demand better when it comes to our bodies. Here's the stuff you may not know. Millions of women live life according to their menstrual cycle, study shows 7 THE PAIN GAME Period cramps, childbirth, endometriosis – we're no strangers to pain. 'I asked if it is feminist folklore that women endure more pain than men,' says Polly, about her interview with Professor Andrew Horne, director of the Centre for Reproductive Health at the University of Edinburgh. His answer? 'God, no, every part of your biological existence involves more pain.' But women put on a brave face. 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The Guardian
9 hours ago
- The Guardian
Can you see circles or rectangles? And does the answer depend on where you grew up?
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The idea is that people in western industrialised countries (these days known by the acronym 'weird' – for western, educated, industrialised, rich and democratic – a summary that is increasingly questionable) see things in a specific way because they are generally exposed to highly 'carpentered' environments, with lots of straight lines, right angles – visual features common in western architecture. By contrast, people from non-'weird' societies – like those in rural Namibia – inhabit environments with fewer sharp lines and angular geometric forms, so their visual abilities will be tuned differently. The study argues that the tendency of rural Namibians to see circles rather than rectangles in the Coffer illusion is due to their environments being dominated by structures such as round huts instead of angular environments. 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The Independent
13 hours ago
- The Independent
The gym bro supplement that may be a game changer for women in midlife
Until recently, creatine supplements was almost exclusively used by athletes and bodybuilders looking to enhance performance and pack on muscle mass. But now there is a surprising rapidly growing market for it: middle aged women. While Dwayne 'The Rock' Johnson still puts in his protein shake to 'put on size,' Ivanka Trump revealed earlier this year she takes a dose with her morning smoothie. From fitness influencers on TikTok to health experts, the chalky powder is now being touted for a range of benefits for women. So, what exactly is creatine and does the science back up the hype? 'Creatine is a natural compound that comes from three amino acids – arginine, glycine, and methionine,' Dr. Rupa Parmar, a physician and Director at Midland Health, tells The Independent. 'It's stored mainly in our muscles to help produce energy.' While small amounts come from foods like red meat and fish, our bodies also make about a gram each day. Most women don't get the recommended three to five grams per day from food, Rupar said, and supplementation may help. 'Women naturally have much lower creatine stores than men and usually eat less of it in their diet, so they may actually benefit more from taking creatine to boost their levels,' he added. Creatine's rise as a go-to supplement can be traced to 1992 when British sprinter Linford Christie and hurdler Sally Gunnell, both vocal about its use, won gold at the Barcelona Olympics. Glossy fitness magazines began branding it a 'breakthrough'; a 1998 article in Fortune magazine called the compound 'nature's steroid'; a Los Angeles Times headline blared, 'Power powder.' While much of its early reputation focused on muscle-building and workout recovery, research suggests creatine's benefits may extend beyond the gym. Creatine has been linked to improved memory, brain health, depression treatment and increased energy. 'It can even support brain health, with studies suggesting the substance helps to improve cognitive function and provide some protection as we age,' Rupar said. A preliminary study by the University of Kansas Medical Center on people with Alzheimer's found that creatine supplements may improve memory and executive function. Creatine may also offer benefits tied to hormonal fluctuations. 'Creatine can help ease fatigue during your period by supporting stable energy levels,' Rupar continued, 'especially when you're feeling more tired.' Oestrogen and progesterone, hormones that regulate the menstrual cycle, influence how the body produces and uses creatine, he explained. 'During the menstrual cycle, creatine levels can change, and supplements may help keep energy and muscle function more stable, especially when oestrogen is low,' Rupar said. For women approaching or going through menopause, creatine appears especially promising as it may help counteract declines in muscle mass, strength, and bone density, particularly when combined with resistance training. One 12-month study found that creatine reduced the loss of bone mineral density in 47 postmenopausal women. For all its potential upsides, creatine isn't without drawbacks. One of the most common complaints is bloating: because it saturates the muscles, it may cause water retention, which sometimes leads to a bloated feeling and a few extra pounds on the scale from water weight. Still, studies have repeatedly shown creatine to be safe for most healthy adults when taken at recommended doses. Experts advise consulting a healthcare provider before starting, especially for those with kidney conditions or who are on medication.
