Toggle light / dark theme

A team of researchers with The NNPDF Collaboration has found new evidence to support the theory of “intrinsic” charm quarks. In their paper published in the journal Nature, the group describes how they used a machine learning model to develop a proton structure and then used it to compare against results from real-world collisions in particle accelerators and what they learned by doing so. Ramona Vogt, with Lawrence Livermore National Laboratory has published a News & Views piece in the same journal issue outlining the work by the team on this new effort. Nature has also published a podcast where Nick Petrić Howe and Benjamin Thompson discuss the work done by the team.

Prior research involving the use of has suggested that contain quarks that are held together by gluons. A reasonable amount of evidence has also shown that there are at least two up quarks and one down . There have also been theories suggesting that there is another, the so-called charm quark, but little real evidence of them exists. That might be changing, however, as the researchers on this new effort have used a new approach to “prove” that they exist.

They have found evidence of one small part (0.5%) of a proton’s momentum coming from a charm quark. The researchers found this new evidence by using a to build a hypothetical proton structure, including different flavors of quarks, and of course the elusive charm quark. They then ran their model and compared characteristics of the model with real-world data that has been observed from over 500,000 collisions in accelerators over the last decade.

A special microscope has visualized changes of electron current distribution that clearly indicate a transition from ohmic to viscous electron flow in graphene.

Imagine a breeze of moist air condensing into water drops and dripping down on a cold glass. Electrons can undergo a transition that resembles this gas-to-fluid condensation: the transition is controlled by temperature and produces a fluid-like state in which electrons display remarkably different dynamics than in the gas-like state. Unlike the condensation of water vapor, however, the electron transition cannot be directly imaged with a camera. One reason for this difficulty is that the pattern of this electron fluid varies at submicron scales that can’t be clearly resolved by visible light. Another reason is that electron collisions and the redistribution of electron currents do not yield a change of surface morphology that can be picked up by light reflection. This imaging challenge has so far limited our microscopic understanding of these types of electronic transitions and their use in practical devices.

Jupiter’s icy moon Europa is an ocean world encased beneath a thick crust of ice — a place where snow floats upward.

The underwater snow forms in the global ocean and travels up though the water to attach to submerged ravines and inverted ice peaks, according to new research. This same phenomenon takes place below ice shelves on Earth — and it may be how Europa builds its ice shell.

The finding, published Monday in the journal Astrobiology, suggested Europa’s ice shell may not be as salty as scientists first thought. Understanding the salt content of the ice crust is crucial as engineers work on assembling NASA’s Europa Clipper spacecraft, which is preparing to launch to Europa in October 2024.

For general readers:

Is it possible that the particle physicists hard at work near Geneva, Switzerland, at the laboratory known as CERN that hosts the Large Hadron Collider, have opened a doorway or a tunnel, to, say, another dimension? Could they be accessing a far-off planet orbiting two stars in a distant galaxy populated by Jedi knights? Perhaps they have opened the doors of Europe to a fiery domain full of demons, or worse still, to central Texas in summer?

Mortals and Portals.

Cells use selective autophagy or self-degradation of undesired proteins to maintain cellular homeostasis (i.e., a state of balance). This process is controlled by autophagy receptors, which mediate the selection of a target protein that is subsequently “cleared.”

Tau proteins, which play a crucial role in the internal architecture of neurons in the brain, abnormally accumulate within neurons in disorders such as dementia and Alzheimer’s.

Alzheimer’s disease is a disease that attacks the brain, causing a decline in mental ability that worsens over time. It is the most common form of dementia and accounts for 60 to 80 percent of dementia cases. There is no current cure for Alzheimer’s disease, but there are medications that can help ease the symptoms.