Author Archives: Attention to the Unseen

Physicists undiscover ‘new particle’

Discover reports: What began as a bump has turned out to be nothing more than a statistical ghost.

Physicists at the International Conference on High Energy Physics in Chicago announced today that the much-discussed 750 GeV aberration in their data discovered by the Large Hadron Collider at the end of last year disappeared upon further testing.

“There is no excess seen in the 2016 data particularly around 750 GeV, confirms Bruno Lenzi, a physicist at CERN. “All over the mass range the data is consistent with the background only hypothesis.”

It was thought that the bump indicated the presence of a much larger particle new to physics, which could have held exciting implications for everything from the search for dark matter to quantum gravity. [Continue reading…]

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There are no ‘good’ or ‘bad’ microbes

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Ed Yong writes: In the 1870s, German physician Robert Koch was trying to curtail an epidemic of anthrax that was sweeping local farm animals. Other scientists had seen a bacterium, Bacillus anthracis, in the victims’ tis­sues. Koch injected this microbe into a mouse – which died. He recovered it from the dead rodent and injected it into another one – which also died. Doggedly, he repeated this grim process for over 20 generations and the same thing happened every time. Koch had unequivocally shown that Bacillus anthracis caused anthrax.

This experiment, and those of contemporaries like Louis Pasteur, confirmed that many diseases are caused by microscopic organisms. Microbes, which had been largely neglected for a couple of centuries, were quickly cast as avatars of death. They were germs, pathogens, bringers of pestilence. Within two decades of Koch’s work on anthrax, he and many others had discovered that bacteria were also associated with leprosy, gonorrhoea, typhoid, tuberculosis, cholera, diphtheria, tetanus, and plague. Microbes became synonymous with squalor and sickness. They became foes for us to annihilate and repel.

Today, we know this view is wrong – as I explain in my new book I Contain Multitudes. Sure, some bacteria can cause disease, but they are in the minority. Most are harmless, and many are even beneficial. We now know that the trillions of microbes that share our bodies – the so-called microbiome – are an essential part of our lives. Far from making us sick, they can protect us from disease; they also help digest our food, train our immune system, and perhaps even influence our behaviour. These discoveries have shifted the narrative. Many people now see microbes as allies to be protected. Magazines regularly warn that antibiotics and sanitisers might be harming our health by destroying our microscopic support system. Slowly, the view that ‘all bacteria must be killed’ is giving ground to ‘bacteria are our friends and want to help us’.

The problem is that the latter view is just as wrong as the former. We cannot simply assume that a particular microbe is ‘good’ just because it lives inside us. There’s really no such thing as a ‘good microbe’ or a ‘bad microbe’. These broad-brush terms belong in children’s stories. They are ill-suited for describing the messy, fractious, contextual relationships of the natural world. [Continue reading…]

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Your Olympic team may be an illusion

Niko Besnier and Susan Brownell write: The parade of athletes in the opening ceremony of the Olympic Games often evokes strong feelings of national pride. After the 2012 Summer Games in London, the Armenian National Committee of America sent a letter of protest to NBC’s CEO and president, Stephen Burke, to complain about the short shrift Armenia received from the commentator, who only said four words about their country: “Armenia, now walking in.” Their grievance paled, however, in comparison to the Olympics-related protest that took place in 1996. Thousands of Chinese people and organizations in the U.S. and elsewhere collected US$21,000 to buy advertisements in prominent newspapers protesting the fact that NBC commentator Bob Costas mentioned human rights abuses, doping allegations, and property rights disputes as the Chinese delegation entered the stadium for the parade.

About a billion people are expected to watch the opening ceremony of the Rio de Janeiro Olympic Games on television on August 5. For most people, the highlight will be watching their country’s athletes walk proudly into the stadium behind their national flag.

The parade of athletes displays a neat world order filled with proud, loyal citizens. But nations are not really the clear political units presented in this happy family portrait. Beneath the surface is a mess of transnational wheeling and dealing by power brokers as well as athletes seeking to get the most reward for their hard work and talent—for themselves and for their families and friends.

In the last few years, well-heeled Persian Gulf states have attracted athletes from other countries by offering them money, training facilities, and the possibility of qualifying for the Olympics more easily than in their home countries. The diminutive but oil-rich emirate of Qatar, for example, has until now played a very modest role in world sports. But in recent years the country has made huge investments in sports and adopted a liberal citizenship policy for athletes. The Qatari national handball team, which reached the finals at the men’s 2015 Handball World Championship, had only four players originating from Qatar on their 17-person squad — the rest had been recruited from overseas. By our calculation, more than half of the 38 athletes who will represent Qatar in Rio were born elsewhere. [Continue reading…]

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Discerning order in randomness

lichen9

Kevin Hartnett writes: Standard geometric objects can be described by simple rules — every straight line, for example, is just y = ax + b — and they stand in neat relation to each other: Connect two points to make a line, connect four line segments to make a square, connect six squares to make a cube.

These are not the kinds of objects that concern Scott Sheffield. Sheffield, a professor of mathematics at the Massachusetts Institute of Technology, studies shapes that are constructed by random processes. No two of them are ever exactly alike. Consider the most familiar random shape, the random walk, which shows up everywhere from the movement of financial asset prices to the path of particles in quantum physics. These walks are described as random because no knowledge of the path up to a given point can allow you to predict where it will go next.

Beyond the one-dimensional random walk, there are many other kinds of random shapes. There are varieties of random paths, random two-dimensional surfaces, random growth models that approximate, for example, the way a lichen spreads on a rock. All of these shapes emerge naturally in the physical world, yet until recently they’ve existed beyond the boundaries of rigorous mathematical thought. Given a large collection of random paths or random two-dimensional shapes, mathematicians would have been at a loss to say much about what these random objects shared in common.

Yet in work over the past few years, Sheffield and his frequent collaborator, Jason Miller, a professor at the University of Cambridge, have shown that these random shapes can be categorized into various classes, that these classes have distinct properties of their own, and that some kinds of random objects have surprisingly clear connections with other kinds of random objects. Their work forms the beginning of a unified theory of geometric randomness. [Continue reading…]

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Neutrinos and antineutrinos hint at an answer to one of the biggest questions in physics

Natalie Wolchover writes: In the same underground observatory in Japan where, 18 years ago, neutrinos were first seen oscillating from one “flavor” to another — a landmark discovery that earned two physicists the 2015 Nobel Prize — a tiny anomaly has begun to surface in the neutrinos’ oscillations that could herald an answer to one of the biggest mysteries in physics: why matter dominates over antimatter in the universe.

The anomaly, detected by the T2K experiment, is not yet pronounced enough to be sure of, but it and the findings of two related experiments “are all pointing in the same direction,” said Hirohisa Tanaka of the University of Toronto, a member of the T2K team who presented the result to a packed audience in London earlier this month.

“A full proof will take more time,” said Werner Rodejohann, a neutrino specialist at the Max Planck Institute for Nuclear Physics in Heidelberg who was not involved in the experiments, “but my and many others’ feeling is that there is something real here.”

The long-standing puzzle to be solved is why we and everything we see is matter-made. More to the point, why does anything — matter or antimatter — exist at all? The reigning laws of particle physics, known as the Standard Model, treat matter and antimatter nearly equivalently, respecting (with one known exception) so-called charge-parity, or “CP,” symmetry: For every particle decay that produces, say, a negatively charged electron, the mirror-image decay yielding a positively charged antielectron occurs at the same rate. But this cannot be the whole story. If equal amounts of matter and antimatter were produced during the Big Bang, equal amounts should have existed shortly thereafter. And since matter and antimatter annihilate upon contact, such a situation would have led to the wholesale destruction of both, resulting in an empty cosmos.

Somehow, significantly more matter than antimatter must have been created, such that a matter surplus survived the annihilation and now holds sway. The question is, what CP-violating process beyond the Standard Model favored the production of matter over antimatter? [Continue reading…]

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The self-reliant individual is a myth that needs updating

Kimberley Brownlee writes: Great loners are fascinating. Henry David Thoreau at Walden Pond, Buddhist monks in their hermitage, and fictional heroes such as Robinson Crusoe are all romantic figures of successful solitary survival. Their setting is the wilderness. Their apparent triumph is the outcome of grit, ingenuity and self-reliance.

One reason that such characters seem appealing is that, ironically, they are reassuring. They give the comforting impression that anyone could thrive in isolation as they do. This reassurance can be summed up in the declaration made by Henrik Ibsen’s Dr Stockmann at the end of An Enemy of the People (1882), after the locals have persecuted him for revealing that the town’s tourist baths are contaminated. Stockmann declares: ‘The strongest man in the world is he who stands most alone.’

The great loners embody an idea of freedom from the vagaries and stresses of social life. As human beings, we are vulnerable to each other’s moods, proclivities, ideologies, perceptions, knowledge and ignorance. We are vulnerable to our society’s conventions, policies and hierarchies. We need other people’s blessing and often their help in order to get resources. When we’re young and when we’re old, we are vulnerable enough that our lives are happy only if other people choose to care about us.

No wonder then that Robinson Crusoe is one of the best-known novels in history; there is solace in the hermit’s self-governing independence. But this romantic image of the eremitic life rests on a mistaken idea of both the great loners’ circumstances and the nature of social isolation. [Continue reading…]

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