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But when it comes to the origin of the Universe, we don’t know what forces are at play. We actually can’t know, since to know such force (or better, such fields and their interactions) would necessitate knowledge of the initial state of the Universe. And how could we possibly glean information from such a state in some uncontroversial way? In more prosaic terms, it would mean that we could know what the Universe was like as it came into existence. This would require a god’s eye view of the initial state of the Universe, a kind of objective separation between us and the proto-Universe that is about to become the Universe we live in. It would mean we had a complete knowledge of all the physical forces in the Universe, a final theory of everything. But how could we ever know if what we call the theory of everything is a complete description of all that exists? We couldn’t, as this would assume we know all of physical reality, which is an impossibility. There could always be another force of nature, lurking in the shadows of our ignorance.

At the origin of the Universe, the very notion of cause and objectivity get entangled into a single unknowable, since we can’t possibly know the initial state of the Universe. We can, of course, construct models and test them against what we can measure of the Universe. But concordance is not a criterion for certainty. Different models may lead to the same concordance — the Universe we see — but we wouldn’t be able to distinguish between them since they come from an unknowable initial state. The first cause — the cause that must be uncaused and that unleashed all other causes — lies beyond the reach of scientific methodology as we know it. This doesn’t mean that we must invoke supernatural causes to fill the gap of our ignorance. A supernatural cause doesn’t explain in the way that scientific theories do; supernatural divine intervention is based on faith and not on data. It’s a personal choice, not a scientific one. It only helps those who believe.

Still, through a sequence of spectacular scientific discoveries, we have pieced together a cosmic history of exquisite detail and complexity. There are still many open gaps in our knowledge, and we shouldn’t expect otherwise. The next decades will see us making great progress in understanding many of the open cosmological questions of our time, such as the nature of dark matter and dark energy, and whether gravitational waves can tell us more about primordial inflation. But the problem of the first cause will remain open, as it doesn’t fit with the way we do science. This fact must, as Einstein wisely remarked, “fill a thinking person with a feeling of humility.” Not all questions need to be answered to be meaningful.

Researchers at Finland’s Aalto University have found a way to use magnets to line up bacteria as they swim. The approach offers more than just a way to nudge bacteria into order – it also provides a useful tool for a wide range of research, such as work on complex materials, phase transitions and condensed matter physics.

The findings have been reported in Communications Physics (“Magnetically controlled bacterial turbulence”).

Bacterial cells generally aren’t magnetic, so the magnets don’t directly interact with the bacteria. Instead, the bacteria are mixed into a liquid with millions of magnetic nanoparticles. This means the rod-shaped bacteria are effectively non-magnetic voids inside the magnetic fluid. When the magnets are switched on, creating a magnetic field, the bacteria are nudged to line up with the magnetic field because any other arrangement takes more energy – it’s harder to keep the rod-shaped holes at an angle to the magnetic field.

The findings could aid the hunt for these monstrous duos using gravitational waves, tiny ripples in space and time (united as a 4-dimensional entity called space-time), which were first predicted in Einstein’s theory of general relativity in 1915.

“These findings are useful for targeted searches for supermassive black hole binaries, in which we search specific galaxies and quasars for continuous gravitational waves from individual supermassive black hole binaries,” research lead author Andrew Casey-Clyde, a doctoral candidate at the University of Connecticut and visiting researcher at Yale University, told Space.com.

“Our results mean that these targeted searches will be up to seven times more likely to find gravitational waves from a supermassive black hole binary in a quasar than in a random massive galaxy,” Casey-Clyde said.

Primordial black holes are tiny versions of the big beasts you typically think of. They’re so small, they could easily fit inside stuff, like a planet, or a star… or a person. So, needless to say, this has piqued the curiosity of our Dead Planeteers.

Leah and Chelsea want to know, can you put primordial black holes inside things and what happens if you do?

Black hole astronomer Allison Kirkpatrick at the University of Kansas is back to help them figure this one out. And it turns out, despite being very small, these black holes are incredibly heavy, so ingesting and/or hugging them seems firmly off the cards — much to Chelsea’s displeasure.

Dead Planets Society is a podcast that takes outlandish ideas about how to tinker with the cosmos – from punching a hole in a planet to unifying the asteroid belt – and subjects them to the laws of physics to see how they fare.

An international research group led by the Italian National Institute for Astrophysics (INAF) and comprising 34 research institutes and universities worldwide utilized the Near-Infrared Spectrograph (NIRSpec) on board the James Webb Space Telescope (JWST) to witness the dramatic interaction between a quasar inside the PJ308–21 system and two massive satellite galaxies in the distant universe.

The observations, made in September 2022, unveiled unprecedented and awe-inspiring details, providing new insights into the growth of galaxies in the early universe. The results, presented July 5 during the European Astronomical Society (EAS 2024) meeting in Padua (Italy), will be published soon in Astronomy & Astrophysics.

Observations of this quasar (already described by the same authors in another study published last May), one of the first studied with NIRSpec when the universe was less than a billion years old (redshift z = 6.2342), have revealed data of sensational quality: the instrument “captured” the quasar’s spectrum with an uncertainty of less than 1% per pixel.

Researchers at Finland’s Aalto University have found a way to use magnets to line up bacteria as they swim. The approach offers more than just a way to nudge bacteria into order—it also provides a useful tool for a wide range of research, such as work on complex materials, phase transitions and condensed matter physics.

The paper is published in the journal Communications Physics.

Bacterial cells generally aren’t magnetic, so the magnets don’t directly interact with the bacteria. Instead, the bacteria are mixed into a liquid with millions of . This means the rod-shaped bacteria are effectively non-magnetic voids inside the magnetic fluid.

Speech recognition, weather forecasts, smart home applications: Artificial intelligence and the Internet of Things are enhancing our everyday lives. Systems based on reservoir computing are a very promising new field.

The research group led by Prof Dr. Karin Everschor-Sitte at the University of Duisburg-Essen (UDE), is conducting research in this area. They are primarily investigating new possibilities for , for example using .

Now, together with specialists from the field of ferroelectric materials, the team has shown that these systems are also suitable for processing complex data faster and more efficiently. Their results have been published in Nature Reviews Physics.

In an ongoing game of cosmic hide and seek, scientists have a new tool that may give them an edge. Physicists at the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) have developed a computer program incorporating machine learning that could help identify blobs of plasma in outer space known as plasmoids. In a novel twist, the program has been trained using simulated data.

The program will sift through reams of data gathered by spacecraft in the magnetosphere, the region of strongly affected by Earth’s magnetic field, and flag telltale signs of the elusive blobs. Using this technique, scientists hope to learn more about the processes governing , a process that occurs in the magnetosphere and throughout the universe that can damage communications satellites and the electrical grid.

Scientists believe that machine learning could improve plasmoid-finding capability, aid the basic understanding of magnetic reconnection and allow researchers to better prepare for the aftermath of reconnection-caused disturbances.