Early Universe seems to run at 20% speed

Researchers have spotted the earliest instance of cosmological time dilation, which makes time seem to run at one-fifth of today’s speed in the early Universe — a phenomenon explained by the general theory of relativity. Observing a quasar hailing from a time when the Universe was just one-tenth of its current age is “like watching a movie with the speed turned down”, says astrophysicist and study leader Geraint Lewis. Quasars are supermassive black holes surrounded by an extremely bright disc of hot gas and are among the oldest objects in the Universe. Previous observation of time dilation made using distant supernovae went back to only around half the age of the Universe, when time seemed to run at 60% of today’s speed.

Blogger Comments:

Time does not "run". Time is a dimension. Time dilation means that the time intervals between the ticks of a clock are longer, which means it takes longer for a clock to tick, which means that processes take longer to unfold. As space intervals expand, time intervals contract, so time intervals in the past were expanded relative to the present.

Dolphin mothers use ‘baby talk’ with their calves

Scientists have dubbed the sing-songy way that parents talk to babies “motherese.” Studies suggest this special baby talk helps infants bond with caregivers and learn the complexities of language. Now, scientists suspect we aren’t the only species with a special way of speaking to our youngest: Bottlenose dolphins (Tursiops truncatus) also raise the pitch of their voice when talking to their calves, according to a study published yesterday in PNAS.

Researchers made the discovery by analysing the whistles of female dolphins in Florida that were undergoing health assessments for ongoing research. The whistles mother dolphins produced around their babies reached higher pitches and exhibited a greater range of frequencies than ones they made when alone or around other dolphins, the team found — shifts similar to the ones human voices make when speaking motherese.

Monster gravitational waves spotted

Gravitational waves are back, and they’re bigger than ever. Researchers have spotted hints of space-time ripples that are light-years long, and thousands of times stronger and longer than the first gravitational waves ever found, in 2015. The first detection used the ground-based Laser Interferometer Gravitational-Wave Observatory (LIGO) detector — this time, scientists tracked changes in the distances between Earth and beacon stars called pulsars to reveal how passing gravitational waves stretch and squeeze space. The waves’ most likely source is the combined signal from many pairs of enormous black holes slowly orbiting each other in the hearts of distant galaxies.

Ancient humans probably ate each other

A carved-up leg bone might be the earliest evidence that ancient humans butchered and ate each other’s flesh. The 1.45-million-year-old hominin bone features cuts similar to the butchery marks made by stone tools found on fossilised animal bones. The scrapes are located at an opportune spot for removing muscle, suggesting that they were made with the intention of carving up the carcass for food. It isn’t possible to say whether this is an example of cannibalism, because the bone belongs to an unidentified hominin species.

Physicists split bits of sound using quantum mechanics

Mechanical waves can be put into superposition, the ability of quantum systems to be in multiple states at the same time until they are measured. Superposition has been demonstrated for quantum particles such as electrons and photons. Quantised sound waves called phonons can also live parallel quantum lives when they’re faced with an acoustic beam splitter, a barrier that phonons can either pass through or bounce back from. It's a step towards building quantum computers that can encode and process information in phonons.

Another exoplanet with no atmosphere

The James Webb Space Telescope has failed, for the second time, to find a thick atmosphere on an exoplanet in the TRAPPIST-1 system, a planetary system that could be hospitable to life. Like its neighbour TRAPPIST-1 b, the planet TRAPPIST-1 c probably never had many ingredients for habitability. There is still a chance that some of the five other TRAPPIST-1 planets might have atmospheres containing geologically and biologically interesting compounds.

‘Breakthrough’ could explain why life molecules are left- or right-handed

Magnetic minerals that were common on ancient Earth might be why nature shows a preference for the ‘left handed’ or ‘right handed’ versions of certain molecules that are essential for life. Some molecules have two mirror-image ‘chiral’ forms, and biology chooses just one: DNA, RNA and their building blocks are all right-handed; amino acids and proteins are all left-handed. Researchers found that magnetic minerals could have created an early surfeit of one-handed versions by causing more of one type to settle on their surfaces, kicking off the biological bias towards a single chiral form.

Laos cave fossils prompt rethink of human migration map

Two human bone fragments — from a skull and a leg — have been unearthed in the Tam Pà Ling cave in Laos. The fossils are older than previous finds from the cave and suggest that early modern humans were in the area up to 86,000 years ago. That’s earlier than previously thought, and calls into question hypotheses that Homo sapiens dispersed out of Africa and through Asia in a single rapid event that happened after the ending of a geological period 80,000 years ago.

A New Experiment Casts Doubt on the Leading Theory of the Nucleus

The leading theory of what’s going on inside atoms can’t properly describe the strong nuclear force. This fundamental interaction binds together protons and neutrons inside an atom’s core. The results of an experiment that measured inflated atomic nuclei, contradicted the theory. It’s still unclear whether the discrepancy could be resolved by including commonly ignored factors in the theoretical calculations or whether there’s a fatal flaw in our understanding of the strong force.

A ‘lost world’ of early microbes thrived one billion years ago

Scientists have discovered a ‘lost world’ of early microorganisms that once thrived in the world’s oceans. Eukaryotes (the group that includes amoebae, mushrooms, plants and people) were thought by some to have become abundant only around 800 million years ago. That’s when ancient rocks bear the telltale signs of the organisms’ existence in the form of fat-like molecules called sterols. But it turns out that precursor ‘protosterol’ molecules are present in rocks dating back even further, to 1.6 billion years ago. The now-extinct eukaryotes that produced these protosterols lived in watery environments between 800 million and 1.6 billion years ago, but were replaced by modern sterol-producing eukaryotes by the end of that period.

JWST spots the most distant ‘smoke’ molecules ever seen in space

The James Webb Space Telescope (JWST) has spied a ‘smoke ring’ of polycyclic aromatic hydrocarbons in a faraway galaxy. The compounds, which are also found in soot and smoke, form near young, massive stars. Because the galaxy is so distant that it appears as it did when the Universe was just 10% of its current age, it must have been busy creating stars during that time.

This infinite tiling pattern could end a 60-year mathematical quest

After 60 years of searching, mathematicians might have finally found a true single aperiodic tile — a shape that can cover an infinite plane and never make a repeating pattern. In March, a team of hobbyist and professional mathematicians found a shape that, together with its mirror image, could be used to build infinite aperiodic tilings. The same team has now modified the shape so it doesn’t need its mirror image to create the never-repeating pattern.

Brain–spine interface allows paralysed man to walk using his thoughts

A wireless connection between the brain and the spinal cord allows a paralysed man to walk using his thoughts. Gert-Jan Oskam, whose legs were paralysed after a cycling accident, received a spinal implant in 2018 that generated robotic movement through pre-programmed electrical stimulation. He has now received head implants that detect brain activity and transmit the signal to a backpack computer, which decodes the information and activates the spinal pulse generator. This brain–spine interface gives Oskam full control over the stimulation, so he can walk and climb stairs.

The Closest Living Relative of the First Animal Has Finally Been Found

Ctenophores, also called comb jellies, are the sister group of all living animals, scientists have discovered. The team compared the comb jelly Bolinopsis microptera to sponges — another contender for the most ancient creature on Earth — along with three unicellular relatives of animals. The pattern of genes on the jellies’ chromosomes revealed that they evolved first. That means that early animals were surprisingly complex: they had a well-developed nervous system, and could probably swim around freely.

JWST spots biggest water plume yet spewing from a moon of Saturn

The James Webb Space Telescope (JWST) has spotted Saturn’s moon Enceladus spraying out a huge plume of very cold water vapour, far bigger than any previously seen there. The enormous cloud could carry the chemical ingredients of life: the salty ocean that lies beneath Enceladus’s icy surface is a possible haven for organisms, which could be sustained by hydrothermal vents.

Human evolution has no single birthplace

Humans did not emerge from a single region of Africa, but from several populations that moved around the continent one million years ago and intermingled for millennia. The widely held idea of a single origin of Homo sapiens is based in part on fossil records. Computer modelling and genome data from modern African and European populations revealed that “our roots lie in a very diverse overall population made up of fragmented local populations”, says evolutionary archaeologist Eleanor Scerri. This means human evolution looks more like a tangled vine than a ‘tree of life.’

Blogger Comments:

Where did the local populations come from?

Astronomers capture largest cosmic explosion ever witnessed

Astronomers have observed the most energetic explosion ever: a fireball 100 times the size of the Solar System and 2 trillion times brighter than the Sun, which has existed for 3 years. The event, dubbed AT2021lwx, might have been caused by an enormous star or cloud of gas being gobbled up by a black hole. The reason why night hasn’t been turned to day here on Earth is that the party is happening 2.5 billion parsecs away. It’s not the brightest event ever seen — that would be the γ-ray burst known as GRB 221009A — but that lasted only a few minutes.

First human ‘pangenome’ aims to catalogue genetic diversity

The first draft of a human ‘pangenome’ has been published. Unlike the first complete human genome sequence, which was derived mostly from the DNA of just one person, the pangenome is drawn from 47 people from around the globe, including individuals from Africa, the Americas, Asia and Europe. More genomes are being added — 350 will be analysed by mid-2024. They will allow geneticists to identify variations in the genomes of diverse populations and investigate links between genes and disease.

Physicists create long-sought topological quantum states

An interlocked ring pattern of virtual exotic particles called non-Abelian anyons — or nonabelions for short — has been created in a quantum computer for the first time. The particles’ paths form Borromean rings, three interlocking rings that can’t be pulled apart but don’t contain any linked pairs. The rings exist only as information inside a quantum computer. They could make the machines more robust to perturbations that create errors in their calculations.

Language model builds better antibodies

A protein language model, a generative artificial intelligence similar to ChatGPT, can improve antibody therapies against viruses such as COVID-19, Ebola and influenza. The models suggested changes to existing antibody therapies that boosted their ability to recognise and block the proteins that viruses use to infect cells. Many of the alterations were outside the regions that are usually the focus of engineering efforts.

New organelle discovered inside animal cell

Biology textbooks look set for an update: researchers have just discovered a new kind of organelle, a tiny organ-like structure inside cells. Researchers made the discovery while investigating the role of phosphate in cell renewal in the guts of fruit flies (Drosophila melanogaster). The new organelle acts as a reservoir for phosphate, a nutrient that is essential for life.

Prehistoric pendant’s DNA reveals the person who held it

A woman who held a deer-tooth pendant some 20,000 years ago left her genetic calling card on the ancient treasure. Scientists unearthed the pendant in Denisova Cave in Siberia, Russia, which was once home to several ancient human species, including the Denisovans. To glean details about who made or wore the pendant, researchers coaxed DNA from inside pores of the tooth — without damaging the priceless item — then compared the genetic sequences with other sets of ancient DNA. The woman was a member of our own species, Homo sapiens, and had north Eurasian ancestry.

Mind-reading machines are here

Scientists have developed the first non-invasive method of determining the gist of imagined speech, presenting a possible communication outlet for people who cannot talk. The thought-to-speech technology relies on functional magnetic resonance imaging and large language models. Researchers used it to decode imagined speech in volunteers while they listened to podcasts. But the results were hit-and-miss, and it was easy to trick the technology. Neuroethicists are split on whether the latest advance represents a threat to mental privacy.

A sapphire Schrödinger’s cat shows that quantum effects can scale up

A sliver of a sapphire crystal close to half the mass of an eyelash has been put in a ‘cat state’: a state of quantum superposition in which its atoms move in two directions at once. This is reminiscent of Schrödinger’s cat, a thought experiment that illustrates quantum superposition by means of a feline that appears to be simultaneously dead and alive until it is observed. The sapphire cat is more than 100 trillion times the mass of the molecules previously put in cat states.

Blogger Comments:

To be clear, the quantum superposition of Schrödinger's Cat is of potential states, alive or dead, one which is instantiated when it is observed.

This research, in contrast, is concerned with actual observed states, not potential unobserved states.

Black-hole image reveals details of turmoil around the abyss

The first image of a black hole blew us away in 2019, showing a ‘ring of fire’ of radio-wavelength emissions swirling around an abyss called M87*. Now, a machine-learning algorithm maximises the resolution of the image to show a substantially thinner ring. And fresh data reveal that a stupendously bright jet of superheated matter, which was observed long before the black hole was imaged, actually emerges from the ring. Astronomers know that jets are ejected from the region surrounding black holes, but it’s still not fully understood how that happens.

James Webb Space Telescope spots planet-making ingredients

The building blocks of planetary formation have been detected in a surprising galaxy, where scientists once thought planets might not emerge. The discovery, made by NASA’s James Webb Space Telescope (JWST), suggests that planet formation could be more common throughout the Universe than previously thought.

Ancient-human genome count surpasses 10,000

More than 10,000 ancient-human genomes have now been sequenced. In 2010, the first ancient-DNA sequence was published, of a man who lived 4,000 years ago. Since 2018, thanks to technological advances, there has been an explosion in the number of ancient genomes sequenced. The vast majority come from people who lived in Europe, Russia and the Middle East.

Comb jellies’ unique fused neurons

Ctenophores, or comb jellies, have surprised scientists with their unusual nervous system: some of their neurons are fused directly to each other. In other animals, neurons are separate cells that communicate through synapses. The discovery suggests that comb jellies’ nervous systems evolved independently of that of all other animals.

Penfold's ‘homunculus’ redrawn to include complex movements

The iconic ‘homunculus’ diagram, which shows how the brain controls individual body parts, has been overhauled to include complex movements. Since the 1930s, the diagram has been used to show a brain region called the primary motor cortex and how it dedicates much more space to some body parts, such as the hands and mouth, than others. Now, hours of magnetic resonance imaging have revealed three interconnected areas that aren’t specific to any one body part. Instead, they connect to parts of the brain that are responsible for critical thinking, maintaining the body’s physiology and planning actions.

Bacterial DNA a key component of vertebrate vision

An ancient gene that our ancestors snatched from bacteria some 500 million years ago became a key component in all vertebrates’ vision. The gene encodes a protein that shuttles light-reactive molecules between cells and is found in all vertebrates — but not in invertebrates. It most closely resembles a class of bacterial genes that encode protein-recycling proteins. Bacteria are known to swap genes, and vertebrates can also incorporate microbial DNA.

Astronomers Spy a Giant Runaway Black Hole’s Starry Wake

Some 40 million years ago, a supermassive black hole escaped the clutches of its host galaxy, leaving a sparkling trail of young stars as it sped away into space. The rogue black hole was first picked up by the Hubble Space Telescope as a faint linear trail. Further observations made with the W. M. Keck Observatory in Hawaii revealed that the streak was a stream of blue stars stretching across a staggering 200,000 light years. The object weighs 20 million Suns and is travelling at more than 1,500 kilometres a second.

Crazy ants’ strange genomes are a biological first

Male yellow crazy ants (Anoplolepis gracilipes) are all chimæras: they are composed of two warring cell lineages with two entirely different sets of genomes. Usually, an organism’s cells all carry the same genes. In yellow crazy ants, some cells carry only maternal and others only paternal genetic material. Chimærism can happen by accident in other animals, but the ants are the first known animal for which this property is an essential aspect of life — although it’s not clear why.

Light waves squeezed through ‘slits in time’

A celebrated experiment in 1801 showed that light passing through two thin slits interferes with itself, forming a characteristic striped pattern on the wall behind. Now, physicists have shown that a similar effect can arise with two slits in time rather than space: a single mirror that rapidly turns on and off causes interference in a laser pulse, making it change colour. The result adds a new twist to the classic double-slit experiment first performed by physicist Thomas Young.

Ancient DNA illuminates Swahili culture’s origins

Genomes point to the diverse origins of Swahili culture, with people carrying a mix of local African, Middle Eastern and South Asian ancestry. Researchers analysed the genomes of 54 individuals buried in Kenya and Tanzania between 1250 and 1800 and found that they were descended from people who began mixing around 1000. Nearly all the East African ancestry seemed to come from women, whereas most of the Asian ancestry was contributed by men from Persia. The results support the oral traditions of Swahili people and dispel the colonial idea that Swahili civilisation is “essentially an Arab civilisation”.

T. rex had lips

Analysis of the teeth and skull of this king of the dinosaurs showed that, unlike its more recent relatives, the crocodiles, Tyrannosaurus rex probably had lips covering its formidable teeth. Most lizards have lips to keep their tooth enamel moist and their delicate dentition protected, and palæontologists have wondered for years whether T. rex was lippy like a lizard or lipless like a croc.

Stressed plants ‘cry’ — and some animals can probably hear them

Thirsty or stressed plants produce ultrasonic clicks that, when processed to make them audible to humans, sound like popping popcorn. Tobacco (Nicotiana tabacum) and tomato (Solanum lycopersicum) plants that needed water, or that had recently had their stems cut, produced up to roughly 35 clicks per hour. Well-hydrated and uncut plants made only about one sound per hour. The noises possibly come from air bubbles forming or breaking in the plants’ xylem, the tubes that transport water and nutrients from the roots to the stems and leaves. The sounds could be used to monitor plants in farming and horticulture.

Molecular syringe ferries proteins into human cells

Researchers have repurposed a bacterium’s molecular ‘syringe’ to deliver proteins, such as the genome-editing Cas9 or a cancer-killing toxin, into human cells or the brains of mice. The bacterium Photorhabdus asymbiotica’s injection system usually works only on insect cells. The team modified the structure of the system so that it would recognize other species’ cells and accept payloads including the Cas9 protein, which is five times larger than the syringe’s usual cargo. The method could be a way to administer protein-based drugs and address one of gene editing’s major bottlenecks: delivering the CRISPR–Cas9 system to where it’s needed.

Brightest gamma-ray burst ever detected defies explanation

The brightest γ-ray burst ever detected is defying theoretical expectations. Since the blast of radiation was first spotted in October 2022, astronomers have been studying its afterglow to learn more about the mechanisms behind it. In two new studies, researchers report that the evolution of the radio waves emitted by the enormous burst was much slower than models predicted.

Best view yet of planet in hotly pursued star system

The exoplanet TRAPPIST-1b — one of seven roughly Earth-sized planets in the TRAPPIST-1 system — probably doesn’t have an atmosphere. It’s not surprising: TRAPPIST-1b is the closest to its star and is blasted by four times as much radiation as Earth receives from the Sun. But the work shows the transformational power of the James Webb Space Telescope (JWST) to observe the system, which offers a unique laboratory for studying planetary environments and how they might become suitable for life.

Brain prosthesis improves memory

A ‘memory prosthesis’ seems to boost people’s ability to remember new information. It consists of a deep-brain electrode that records and then mimics the electrical activity pattern of the hippocampus, a brain region that has a crucial role in memory. Twenty-four people, who had already had electrodes implanted to study their epilepsy, volunteered to try the device: it improved their performance in short- and long-term memory tests by up to 54%.

A fish can sense another’s fear

Zebrafish (Danio rerio) become afraid when they see other members of their species in distress. This fear mirroring is regulated by oxytocin: fish that lack the genes to produce and absorb the hormone fail to detect others’ anxiety but regain the ability when they receive an oxytocin injection. Oxytocin has the same effect in mice, and is known to affect humans’ social responses, meaning it’s likely that this empathy mechanism evolved many millions of years ago, before fish and mammals diverged on the tree of life.

Mathematicians have finally discovered an elusive ‘einstein’ tile

Researchers have discovered the first example of a single shape that can cover a surface with an infinite pattern that never repeats. The shape is surprisingly simple: a 13-sided polykite that the team has dubbed ‘the hat’. The hat’s sides can vary in length without it losing the ability to create ‘aperiodic tiling’. Previous examples of aperiodic tilings, such as Penrose tiles, required two or more shapes.

Fruit flies are first known animals that can taste alkaline foods

Fruit flies (Drosophila melanogaster) have surprised researchers with an entirely new taste receptor that allows them to detect alkaline — or basic — substances and avoid toxic meals and surfaces. The flies have an unusual mechanism: a receptor protein that, in the presence of a base, opens a cell-membrane channel through which negatively charged chloride ions escape the neuron. Most sensory receptors involve channels that let positively charged ions flow into the cell. Some studies in people and cats suggest that they, too, experience alkaline as a type of taste.

How humans settled the roof of the world

Modern inhabitants of the Tibetan Plateau are descendants of people who have lived there for 5,000 years. In the biggest study of its kind, researchers sequenced ancient genomes from the remains of 89 individuals unearthed from 29 archæological sites. The genomes suggest that Tibet’s first settlers arrived from the east — in contrast to the rest of South and Central Asia. And researchers saw the increasing prevalence of a variant of the EPAS1 gene that allows people to thrive at high altitudes.

How stem cells make a human brain

Scientists have followed the developmental destiny of individual human brain cells as they progress from stem cells to specialised structures in the brain. In a technical “tour de force”, the team painstakingly purified and classified undifferentiated brain cells from human fœtuses. The cells were injected into mouse brains, and, six months later, the researchers analysed the cellular identities that the cells’ progeny had taken.

Volcano eruption spotted on Venus

Scientists think they’ve spotted a volcano erupting on Venus. Radar images taken 8 months apart by NASA’s Magellan spacecraft in the early 1990s show changes to a volcanic vent that suggest an eruption or magma flow. Venus is covered in volcanoes, and this is some of the strongest evidence yet that at least one of them is still active. Venus doesn’t have plate tectonics that could drive volcanic activity, so it could be caused by heat released from radioactive elements.

Heartbeat May Shape Our Perception of Time, Study Shows

Our perception of time might be in part driven by heartbeats. When 45 students were asked to estimate the length of audio tones, the people with long intervals between their heartbeats perceived the tone as longer, whereas the people with shorter intervals thought it was shorter.

First full brain map of a complex animal

Scientists have mapped all 3,016 neurons and 548,000 connecting synapses in a young fruit fly’s (Drosophila melanogaster) brain. It’s the first complete brain map of a complex animal that can learn, and weigh the risks and benefits of its actions. The only other animals whose brains have been completely mapped are two worm species and the larva of a sea squirt. The neural circuit diagram will help researchers to study how the brain works and neurological diseases.

Asteroid lost 1 million kilograms after collision with DART spacecraft

The asteroid that was deliberately hit with NASA’s Double Asteroid Redirection Test (DART) spacecraft last September lost one million kilograms of rock, gained a 1,000-kilometre-long debris tail and now completes its orbit 33 minutes faster than before the collision. A detailed analysis of what happened when DART smashed into the Great-Pyramid-sized asteroid Dimorphos has revealed how successful this first test of planetary defence really was. The spacecraft hit a spot close to the asteroid’s centre and caused a large spray of rubble to fly outwards, which maximised the impact’s force and added momentum.

Ancient genomes show how humans escaped Europe’s last ice age

European hunter-gatherers holed up in what is now Spain to escape the last ice age, which covered large parts of the continent with glaciers for several millennia. Researchers analysed DNA from 356 individuals who lived in Europe and western Asia between 35,000 and 5,000 years ago. The humans who had sought out the warmer climate on the Iberian Peninsula repopulated Western Europe after the deep freeze ended. This explains how a genetic signature that first showed up in 35,000-year-old remains popped up again in populations tens of thousands of years later — a fact that had remained a mystery until now.

The molecule that kickstarted life

For more than 15 years, scientists have been on a quest: create a functional ‘protoribosome’, a reconstructed version of the protein-building machine that many think might have helped to kickstart life on Earth. The modern ribosome is a key ingredient of life as we know it because it translates genetic information into proteins. At its heart sits a small RNA pocket that some think might be closest to what the very first ribosome looked like. Now, there’s proof that some reconstructed protoribosome-like RNAs can link amino acids — the first step to making proteins. Some scientists say there are other ways for proteins to emerge, without a ribosome. But others are already thinking about repurposing these simple machines to manufacture new kinds of biomolecule.

Physicists Use Quantum Mechanics to Pull Energy out of Nothing

Researchers have shown that energy can be pulled out of empty space by taking advantage of random fluctuations in the quantum fields that fill the vacuum. Physicists exploited quantum entanglement to swap information about the fluctuations, gathered in one place, with energy hoovered up somewhere else. In one experiment, they used radio pulses to link two carbon atoms in a way that effectively teleported energy across microscopic distances for a few milliseconds. A separate experiment tested quantum energy teleportation using several of IBM's superconducting quantum computers.

How dinosaurs got big (and small)

Extinct theropod dinosaurs, which include iconic species such as Tyrannosaurus rex, used more than one evolutionary trick to become big: some had explosive growth spurts, whereas others grew slowly over time. Palæontologists had always assumed that dinosaurs developed like modern birds and mammals, in which larger species grow faster during their most rapid growth period. Now, researchers who analysed growth rings in the shin bones of 42 dinosaur species have discovered that this is true for only 31% of theropods — 28% showed prolonged growth similar to that of modern crocodiles. Of the species that became smaller than their ancestors, 21% did so by shortening their growth spurts and 19% by slowing their growth.