Lifeboat Foundation

The scent of coffee. The clarity of sunlight dappling through the trees. The howl of the wind in the dark of night.

All this, according to a philosophical argument published in 2003, could be no more real than pixels on a screen. It’s called the simulation hypothesis, and it proposes that if humanity lives to see a day it can repeatedly simulate the Universe using come kind of computer, chances are we are living in one of those many simulations.

If so, everything we experience is a model of something else, removed from some kind of reality.

Pulsars are known for their regularity and stability. These fast-rotating neutron stars emit radio waves with such consistent pulses that astronomers can use them as a kind of cosmic clock.

But recently a pulsar emitted gamma rays with tremendous energy. The gamma rays were the most energetic photons ever observed, with energies of more than 20 teraelectronvolts, and astronomers are struggling to understand how that’s possible.

The results were published in Nature Astronomy, which describes the burst of gamma rays emanating from the Vela Pulsar.

Some asteroids have measured densities higher than those of any elements known to exist on Earth. This suggests that they are at least partly composed of unknown types of “ultradense” matter that cannot be studied by conventional physics.

Jan Rafelski and his team at the Department of Physics, The University of Arizona, Tucson, U.S., suggest that this could consist of superheavy elements with atomic number (Z) higher than the limit of the current periodic table.

They modeled the properties of such elements using the Thomas-Fermi model of atomic structure, concentrating particularly on a proposed “island of nuclear stability” at and around Z=164 and extending their method further to include more exotic types of ultra-dense material. This work has now been published in The European Physical Journal Plus.

Interstellar magnetic fields perturb the trajectories of cosmic rays, making it difficult to identify their sources. A new survey of gamma radiation produced when cosmic rays interact with the interstellar medium should help in this identification.

Scientists know that the diffuse gamma-ray glow that suffuses the Milky Way is mainly produced by the interaction of high-energy cosmic rays with interstellar gas. But questions remain about the properties of these cosmic rays. What, for example, is their energy limit? And how do cosmic rays propagate from their sources? These long-standing mysteries could potentially be solved by observations of the highest-energy diffuse gamma rays. To this end, researchers working on the square kilometer array (KM2A) at the Large High Altitude Air Shower Observatory (LHAASO) experiment in China have reported precise measurements of the energy spectra of diffuse gamma rays over a wide energy range and across a large swath of the Galaxy [1]. Their results will give new insight into the propagation, interaction processes, and origin of the highest-energy cosmic rays in our Galaxy.

Since their discovery in 1912, cosmic rays—mainly comprising high-energy protons—have been observed across an energy range of more than 10 orders of magnitude. But in 1958, scientists found that the cosmic-ray flux decreases rapidly beyond an energy of a few PeV [2]. Researchers have explained this spectral cutoff by hypothesizing that cosmic rays accelerated to up to a few PeV are confined by the Galactic magnetic field for 10⁴–10⁷ years and accumulate in a “cosmic-ray pool” (Fig. 1): these are the cosmic rays whose interactions with interstellar gas are responsible for most of the diffuse gamma rays. Cosmic rays above a few PeV, meanwhile, are thought to escape from our Galaxy, therefore contributing relatively little to the gamma-ray haze.

Falling through the Solar System at an astonishing 635,266 kilometers (394,736 miles) per hour, NASA’s Parker Solar Probe has just smashed the record for fastest object ever to be created by human hands.

The event on September 27 marks the turning point of the mission’s 17^th loop around the Sun as it collects data on the heated winds of charged particles and violent magnetism that surround our closest star, and comes just under three years after its previous record of 586,863.4 kilometers (364,660 miles) per hour.

At these speeds, it’d be possible for an aircraft to circumnavigate our planet roughly 15 times in a single hour, or zoom from New York to Los Angeles in just over 20 seconds.

https://www.youtube.com/watch?v=tP1Yo1pHiz8

Martian landscapes by images NASA/JPL-Caltech/UArizona modified by Mariagata1959.

/ each image is up to approximately 25 km.in diameter /

Music by Voonboyd.

Caltech researchers have discovered Hubbard excitons, which are excitons bound magnetically, offering new avenues for exciton-based technological applications.

In art, the negative space in a painting can be just as important as the painting itself. Something similar is true in insulating materials, where the empty spaces left behind by missing electrons play a crucial role in determining the material’s properties. When a negatively charged electron is excited by light, it leaves behind a positive hole. Because the hole and the electron are oppositely charged, they are attracted to each other and form a bond. The resulting pair, which is short-lived, is known as an exciton [pronounced exit-tawn].

Excitons are integral to many technologies, such as solar panels, photodetectors, and sensors. They are also a key part of light-emitting diodes found in televisions and digital display screens. In most cases, the exciton pairs are bound by electrical, or electrostatic, forces, also known as Coulomb interactions.

At the edge of the universe, billions of light years away, there’s a time when the first galaxies were just beginning to light up. Think of it as the universe’s childhood. Scientists have always been keen to study this era because it helps us understand how galaxies, like our own Milky Way, came into existence. Recently, the James Webb Space Telescope (JWST), gave us an unprecedented peek into this ancient time, revealing some exciting and unexpected finds.

The JWST found a lot of really bright, big galaxies from that early era. This was surprising because we didn’t expect such large galaxies to exist so early in the universe’s history. These discoveries left astronomers with many questions. Were these bright galaxies truly from that ancient era? If they were, how did they form so quickly? And do these new findings fit with our current understanding of the universe’s history and growth?

Northwestern University researchers may have cracked the mystery. Contrary to initial beliefs, these galaxies might not be as massive as they appear. Instead, scientists say their eye-catching brightness could result from sudden, dazzling bursts of star creation.

The James Webb Space Telescope has taken a stunning image of a perfectly formed Einstein ring, which is also the most distant gravitationally lensed object ever detected.