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The Universe Itself Might Be Hiding the Gravity Particle From Us

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To progress to the next level in understanding reality, we need to combine quantum mechanics and Einstein’s general relativity. And to do that, most physicists believe we need a theory of quantum gravity… which means we need gravitons. But it also seems like the laws of physics make it impossible to ever detect this quantum particle of gravity. Almost like the universe is set up to keep the final answer forever out of our reach. So, can we outsmart the universe, catch a graviton, and finally solve physics?

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https://mailchi.mp/1a6eb8f2717d/space… the Entire Space Time Library Here: https://search.pbsspacetime.com/ Hosted by Matt O’Dowd Written by Richard Dyer & Matt O’Dowd Post Production by Leonardo Scholzer Directed by Andrew Kornhaber Associate Producer: Bahar Gholipour Executive Producer: Andrew Kornhaber Executive in Charge for PBS: Maribel Lopez Director of Programming for PBS: Gabrielle Ewing Assistant Director of Programming for PBS: John Campbell Spacetime is a production of Kornhaber Brown for PBS Digital Studios. This program is produced by Kornhaber Brown, which is solely responsible for its content. © 2025 PBS. All rights reserved. End Credits Music by J.R.S. Schattenberg: / multidroideka Space Time Was Made Possible In Part By: Big Bang Alexander Tamas David Paryente Juan Benet Kenneth See Mark Rosenthal Morgan Hough Peter Barrett Santiago Tj Steyn Vinnie Falco Supernova Ethan Cohen Glenn Sugden Grace Biaelcki Mark Heising Stephen Wilcox Tristan Lucian Claudius Aurelius Tyacke Hypernova Alex Kern Ben Delo Cal Stephens chuck zegar David Giltinan Dean Galvin Donal Botkin Gregory Forfa Jesse Cid Dyer John R. Slavik Justin Lloyd Kenneth See Massimiliano Pala Michael Tidwell Mike Purvis Paul Stehr-Green Scott Gorlick Scott Gray Spencer Jones Stephen Saslow Thomas Mouton Zachary Haberman Антон Кочков Daniel Muzquiz Gamma Ray Burst Aaron Pinto Adrien Molyneux Almog Cohen Anthony Leon Arko Provo Mukherjee Ayden Miller Ben McIntosh Bradley Jenkins Bradley Ulis Brandon Lattin Brian Cook Bryan White Chris Liao Christopher Wade Chuck Lukaszewski Collin Dutrow Craig Falls Craig Stonaha Dan Warren Daniel Donahue Daniel Jennings Daron Woods Darrell Stewart David Johnston Doyle Vann Eric Kiebler Eric Raschke Eric Schrenker Faraz Khan Frederic Simon Harsh Khandhadia Ian Williams Isaac Suttell James Trimmier Jeb Campbell Jeremy Soller Jerry Thomas jim bartosh John Anderson John De Witt John Funai John H. Austin, Jr. John591 Joseph Salomone Junaid Ali Kacper Cieśla Kane Holbrook Keith Pasko Kent Durham Koen Wilde Kyle Atkinson Marcelo Garcia Marion Lang Mark Daniel Cohen Mark Delagasse Matt Kaprocki Matthew Johnson Michael Barton Michael Clark Michael Lev Michael Purcell Nathaniel Bennett Nick Hoffenstoffer III Nicolas Katsantonis Paul Wood Rad Antonov Reuben Brewer Richard Steenbergen Robert DeChellis Ross Story Russell Moore SamSword Sandhya Devi Satwik Pani Sean Owen Shane Calimlim SilentGnome Sound Reason Steffen Bendel Steven Giallourakis Terje Vold Thomas Dougherty Tomaz Lovsin Tybie Fitzhugh Vlad Shipulin William Flinn WILLIAM HAY III Zac Sweers.

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Peter van Inwagen — Does a Fine-Tuned Universe Lead to God?

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We human beings sit roughly midway between the sizes of atoms and galaxies, and both must be so perfectly structured for us to exist. It’s called ‘fine-tuning’ and it’s all so breathtakingly precise that it cries out for explanation. To some, fine-tuning leads to God. To others, there are non-supernatural explanations. Both are startling.

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Peter van Inwagen is an analytic philosopher and the John Cardinal O’Hara Professor Emeritus of Philosophy at the University of Notre Dame.

The Theory Of Everything That Nobody Talks About

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There are a whole lot of people with “theories of everything” – theories which supposedly explain how the whole universe works. Most of the time, these theories fall very short of that goal. Causal Fermion Systems are an approach that actually seems promising… though it still has its flaws. Today I have a brief summary of what might be the most underreported theory of everything out there.

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Confirming altermagnetism in an abundant mineral

Also known as magnetoelectronics, spintronics rely on electron spin rather than electron charge, as found in traditional electronics. Although spintronics is still an emerging field, spintronic technologies are already found in hard disk drives and giant magnetoresistance sensors used in industrial and automotive applications. Once the right foundational materials are discovered and verified, including economical materials for altermagnets, spintronics could advance technologies from wireless communication to quantum computing.

Researchers using neutrons at the Department of Energy’s Oak Ridge National Laboratory’s Spallation Neutron Source (SNS) discovered that hematite, essentially rust, can help design energy-efficient spintronics.

The team’s findings, published in Physical Review Letters, confirmed a key signature of altermagnetism (a new type of magnetism discovered in 2022) in hematite. Altermagnets are magnetic materials in which electron spins align in opposite directions, allowing pure spin currents to flow without a net electric charge—ideal conditions for spintronics. The team measured spin waves, which move through a material’s magnetic order similar to how sound waves move through air. They discovered that these waves show a clear separation in energy, a unique signature that confirms the material’s altermagnetic nature.

New laser method gives insight into radioactive atomic nuclei

By directing pulses of laser light at atoms, researchers can study how radioactive elements decay in a matter of seconds. The method is described in a new thesis from the University of Gothenburg, which shows that the atomic nuclei of the elements neptunium and fermium are shaped like rugby balls.

Actinides are a group of elements at the bottom of the periodic table. They have a high density, are radioactive, and several of them only exist for a few seconds before they decay. Only four of the 14 elements in this group occur naturally on Earth. The others can be produced in an accelerator, but only in very small quantities. Uranium is the best-known actinide, but a new thesis from the University of Gothenburg focuses on neptunium and fermium.

The Gravity Particle Should Exist. So Where Is It?

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Physics is this close to understanding the entire universe. And what lives in this gap? Many physicists think it’s the elusive graviton—the quantum particle of gravity—whose discovery will finally allow us to stitch together our two great theories of nature into a single master theory. But what is the graviton, and does it even exist?

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Superconductor Theory Under Cold-Atom Scrutiny

Snapshot measurements of cold-atom gases reveal hidden spin correlations that could force an update of some superconductivity theories.

Our understanding of nature is inherently bound to the experimental tools we build to observe the world. Superconductivity, for example, has been traditionally studied using current and voltage meters under a variety of temperatures and other environmental conditions. From these observations, theorists have developed models—notably the Bardeen-Cooper-Schrieffer (BCS) theory, which assumes that the zero-resistance flow in a superconductor arises from electrons forming so-called Cooper pairs. This theory has been successful in explaining a large class of superconductors, but Tarik Yefsah from the Ecole Normale Supérieure in Paris and colleagues have now observed behavior that contradicts BCS predictions [1]. Using a recently developed technique called atom-resolved continuum quantum gas microscopy, the researchers directly observed spatial correlations in cold atoms that mimic superconducting electrons.

Astronomers crack a decades-old mystery, catching gas morphing into planet-building disks around newborn stars

An international team led by Dr. Indrani Das of Academia Sinica Institute of Astronomy and Astrophysics (ASIAA) has shown, for the first time, how infalling gas from star-forming cores gradually transitions into planet-forming disks. Their findings, combining numerical simulations with Atacama Large Millimeter/submillimeter Array (ALMA) observations, are published today in The Astrophysical Journal.

Protoplanetary disks form around young stars when dense molecular cloud cores collapse under their own gravity. An outer shroud of gas and dust, known as the envelope, surrounds and feeds both the young star and the forming disk. While it is well understood that planets eventually form within these disks and follow Keplerian orbits, the mechanism that transforms rapid infalling gas motion from the envelope into ordered Keplerian motion within the disk has remained a mystery for decades.

Based on both theoretical and observational evidence, the recent study discovered that there exists a distinct transition zone at the envelope-disk interface of a young star-disk system, which Das named ENDTRANZ (Envelope Disk Transition Zone). The findings have established that infalling gas motions gradually transition into Keplerian motions across this transition zone. Crucially, this transition is far from abrupt and contradicts earlier infall models that are based on classical test-particle dynamics.

Dark matter could explain the earliest supermassive black holes

A growing mystery in astronomy is the presence of gargantuan black holes—some weighing as much as a billion suns—existing less than a billion years after the Big Bang. According to the standard theory of black hole formation, these black holes simply should not have had enough time to grow so large. A study led by University of California, Riverside graduate student Yash Aggarwal shows that dark matter decays could be the key to understanding the origin of these cosmic behemoths. Published in the Journal of Cosmology and Astroparticle Physics, the research shows that the energy released from dark matter decay could alter the chemistry of early galaxies enough to cause some of them to directly collapse into black holes rather than forming stars.

The result is timely, since NASA’s James Webb Space Telescope continues to observe unusually large black holes in the early universe that could have formed by direct collapse. Astronomers had believed this process requires a coincidence of nearby stars shining onto pre-stellar gas and so expected it to be rare.

Aggarwal’s team goes beyond the standard approach by using dark matter—the unknown 85% of the matter in the universe that helps form galaxies. They show that if dark matter decays, it can leak a small amount of its energy into the gas and supercharge the direct collapse rate. Each decaying dark matter particle would only need to inject an amount of energy that is a billion trillionths of the energy of a single AA battery.

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