the physics arXiv blog

Category: Slimey stuff

  • Extraterrestrial nucleobases found in meteorite

    In 1969, a large meteorite fell near the town of Murchison in Victoria, Australia. Scientists collected more than 100 kilograms of rock, making it the largest sample of carbonaceous chondrite ever recovered. Since then numerous groups have found evidence that the Murchison meteorite contains common amino acids, the building blocks of proteins, as well as…

  • How ESA plans to search for other Earth’s

    We’re getting close to the day when we’ll spot an Earth-like planet orbiting another star. Astronomers have already seen a number of superEarth candidates–rocky planets in the habitable zone that are many times larger than Earth. They’ve even begun to analyse the atmosphere of these places and got some idea of what it might be…

  • Modelling how birds mistime egg-laying due to climate change

    Many birds have to time egg-laying to coincide with a peak in food availability, for example , to match the hatching shcedule of a particular type of caterpillar. This is a tricky business because many caterpillars are available for only a few weeks and the birds must lay their eggs around a month in advance…

  • Quantum zeno effect explains bird navigation

    Just how birds use the earth’s magnetic field to navigate has puzzled researchers for decades. But in recent years, a growing body of evidence points to the possibility that a weak magnetic field can influence the outcome of a certain type of chemical reaction in bird retinas involving radical ion pairs. The idea is that…

  • Criticality and the brain

    Our understanding of how various parts of brain function is advancing at breakneck speed and yet we are as far away as ever from an overarching “theory of the brain” that attempts to encompass these discoveries. Such a theory would unite disparate discoveries in brain science under a unifying theme. Now Dante Chialvo from Northwestern…

  • The wound ballistics question

    The gloves are off in the world of wound ballistics. The question is: how do handgun bullets do their damage? According to Martin Fackler, a retired colonel and battlefield surgeon in the US Army Medical Corp, the main cause of injury is along or close to the wound channel, the path the bullet takes through…

  • Winning and the marathon of life

    Look at the finishers in a typical marathon and a simple pattern immediately emerges. After the race winner, there is a trickle of fast finishers that gradually turns into a steady flow as the finish time approaches 3 hours. The main pack arrives in the range of 3–6 hours, with a decreasing stream of progressively…

  • How plankton blooms are born

    Massive plankton blooms are the plague of the oceans. They starve local species by exhausting an ocean of its food and oxygen, they turn vast areas of sea to the colour of milk and have a profound effect on the ocean food web. But where do they come from? Nobody knows. At least they didn’t…

  • The physics of human body weight changes

    If you put on a few pounds over the holiday season, this may interest you. Weight changes are the result of an imbalance between the energy you derive from the food you’ve eaten and the energy you’ve been expending to maintain life and perform physical work. At first glance, you’d think this would be a…

  • Model successfully predicts brain structure

    The neuronal circuits in the part of your brain called the cerebral cortex are amongst the most complex structures in nature. Nobody knows how they form but it seems likely that self organisation plays a critical role. Researchers have studied various models of self organisation that might explain how these circuits form but have come…