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Parallel realities solve this time travel paradox | Jim Al-Khalili

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Time is the one thing every human being experiences identically, or so we assume.

Physicist Jim Al-Khalili dismantles that assumption, explaining how velocity and gravity don’t just affect clocks but actually alter the rate at which time passes for the person experiencing it.

Preorder Jim Al-Khalili’s forthcoming book, On Time: The Physics That Makes the Universe, here: https://www.amazon.com/Time-Physics-T?tag=lifeboatfound-20

About Jim Al-Khalili: Jim is a multiple award-winning science communicator renowned for his public engagement around the world through writing and broadcasting and a leading academic making fundamental contributions to theoretical physics, particularly in nuclear reaction theory, quantum effects in biology, open quantum systems and the foundations of quantum mechanics. Jim is a theoretical physicist at the University of Surrey where he holds a Distinguished Chair in physics as well as a university chair in the public engagement in science. He received his PhD in nuclear reaction theory in 1989 and has published widely in the field. His current interest is in open quantum systems and the application of quantum mechanics in biology.

About Jim Al-Khalili:

How to create a Universe with Jan Pieter van der Schaar

What do we mean with the ‘Big Bang’? Why are the properties of our universe so special? What is cosmological inflation? How can we test cosmological inflation and what do the latest observations tell us? Can we probe string theory using cosmology?

How did our universe come into existence? This basic and ancient question still remains one of the biggest mysteries in science. Ever since Einstein discovered that gravity can be understood as the stretching and bending of space and time, cosmology, which studies the properties, evolution and origin of the universe as a hole, became a proper and honest scientific subject, in which theoretical constructs can be confronted with (cosmological) observations.

What we have learned since then, in less than a century, about the origin and properties of our universe, is spectacular and at the same time mysterious. Our universe appears to be very special. In an attempt to explain these remarkable features a small group of theoretical cosmologists developed the paradigm of cosmological inflation in the eighties. What is cosmological inflation? An what do the latest observations tell us about this fascinating proposal in which all structures in our universe find their origin in small primordial quantum fluctuations? And what are the implications of cosmological inflation for conjectured theories of quantum gravity, such as string theory?

String theorist Jan Pieter van der Schaar argues that cosmology in general, and the cosmological paradigm of inflation in particular, is our best (and perhaps only) bet to probe and test the microscopic quantum description of space and time.

An Pieter van der Schaar is a string theorist by training, with a Ph.D. at the University of Groningen in 2000. After postdoctoral research stints at the University of Michigan, the Cern theory group, and Columbia University, he developed into a theoretical cosmologist with a particular interest to connect cosmological models to string theory and vice versa. Jan Pieter has been a member of the string theory and cosmology group at the Institute of Physics of the University of Amsterdam since 2006. Since 2013 he is the coordinator of the Delta Institute for Theoretical Physics and as of 2022 he is heading the ‘Building Blocks of Matter and Foundations of Space-time’ route as part of the Nationale Wetenschapsagenda.

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The Arrow of Time and How to Reverse It

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Ever wish you could travel backward in time and do things differently? Good news: the laws of physics seem to say traveling backward in time is the same as traveling forwards. So why do we seem to be stuck in this inexorable flow towards the future? It’s time to begin our journey towards really understanding time.

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https://mailchi.mp/1a6eb8f2717d/space… by Matt O’Dowd Written by Matt O’Dowd Graphics by Leonardo Scholzer, Yago Ballarini, & Pedro Osinski Directed by: Andrew Kornhaber Assistant Producer: Setare Gholipour Executive Producers: Eric Brown & Andrew Kornhaber End Credits Music by J.R.S. Schattenberg: / @julesschattenberg Special Thanks to Our Patreon Producers Big Bang Supporters Sean Maddox Marty Yudkovitz Brodie Rao Scott Gray Ahmad Jodeh Radu Negulescu Alexander Tamas Morgan Hough Juan Benet Fabrice Eap Mark Rosenthal David Nicklas Quasar Supporters Justin Lloyd Christina Oegren Mark Heising Vinnie Falco Hypernova Supporters William Bryan L. Wayne Ausbrooks Nicholas Newlin Mark Matthew Bosko Justin Jermyn Jason Finn Антон Кочков Alec S-L Julian Tyacke John R. Slavik Mathew Danton Spivey Donal Botkin John Pollock Edmund Fokschaner Joseph Salomone Matthew O’Connor chuck zegar Jordan Young m0nk Hank S John Hofmann Timothy McCulloch Gamma Ray Burst Daniel Jennings Cameron Sampson Pratik Mukherjee Geoffrey Clarion Astronauticist Nate Darren Duncan Lily kawaii Russ Creech Jeremy Reed Max Bernard Bill Blair Eric Webster Steven Sartore DrJYou David Johnston J. King Michael Barton Christopher Barron James Ramsey Mr T Andrew Mann Jeremiah Johnson fieldsa eleanory Peter Mertz Kevin O’Connell Richard Deighton Isaac Suttell Devon Rosenthal Oliver Flanagan Dawn M Fink Bleys Goodson Darryl J Lyle Robert Walter Bruce B Ismael Montecel Andrew Richmond Simon Oliphant Mirik Gogri David Hughes Mark Daniel Cohen Brandon Lattin Yannick Weyns Nickolas Andrew Freeman Brian Blanchard Shane Calimlim Tybie Fitzhugh Robert Ilardi Astaurus Eric Kiebler Craig Stonaha Martin Skans Michael Conroy Graydon Goss Frederic Simon Greg Smith Sean Warniaha Tonyface John Robinson A G Kevin Lee Adrian Hatch Yurii Konovaliuk John Funai Cass Costello Geoffrey Short Bradley Jenkins Kyle Hofer Tim Stephani Luaan AlecZero Malte Ubl Nick Virtue Scott Gossett Martin J Lollar Dan Warren Patrick Sutton John Griffith Daniel Lyons DFaulk Kevin Warne Andreas Nautsch Brandon labonte Lucas Morgan.

Hosted by Matt O’Dowd.

Scientists witness birth of one of the universe’s strongest magnets for the first time, thanks to a general relativity ‘magic trick’

Astronomers have detected strange “wobbles” in the light curve of a super bright supernova, hinting that a magnetar was born inside the extreme stellar explosion.

Why Information Cannot Be Destroyed — Leonard Susskind

🚨 THE UNIVERSE NEVER FORGETS. NOT A SINGLE MOMENT. You burned a book. The words are gone. The pages are ash. But physics says every letter still exists — scattered across trillions of particles, encoded in the quantum state of reality. And it’s not just books. Every breath you’ve ever taken. Every word you’ve ever spoken. Every person you’ve ever lost. The information is still here. Right now. Permanently.
🔴 WHAT YOU’LL DISCOVER:
🔴 Why burning something doesn’t destroy its information.
🔴 How Stephen Hawking lost the biggest bet in physics history.
🔴 The black hole war that nearly broke quantum mechanics.
🔴 Why spacetime itself is made of information.
🔴 What this means about death — and why nothing truly disappears.
⚠️ WARNING: After this video, you will never look at destruction the same way again.
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physics, quantum mechanics, information paradox, black holes, Hawking radiation, holographic principle, entropy, universe, science, reality, quantum information, spacetime, Leonard Susskind, Stephen Hawking, ER EPR.

We’ve misunderstood the physics of our universe | Sabine Hossenfelder, Ivette Fuentes, James Ladyman

Sabine Hossenfelder, Ivette Fuentes and James Ladyman discuss the scaling laws of the universe and the fundamental nature of reality.

Is the universe one thing, or many things?

With a free trial, you can watch the full debate NOW at https://iai.tv/video/the-one-and-the–… central question in ancient Greek philosophy was the problem of the One and the Many. It is a question that has echoed across Western culture and is still with us today. Should we see the world as a coherent whole or a multitude of separate parts? The puzzle is that we need both the whole and the parts, but an explanation of the relationship between them has proved problematic and perhaps unknowable. In contemporary physics, the parts are the teeming world of particle physics, and these should make up the cosmological world of the universe as a whole and the overall framework of Einsteinian space-time. But as yet we have not been able to combine the two coherently. Is looking at the universe from the small scale and the large always going to be incompatible? Does it mean a theory of everything is an illusion and the attempt to combine quantum mechanics and Einstein’s general relativity a forlorn project? Or is the parallel with the ancient Greek puzzle accidental and the current challenge one that might be overcome? #quantumphysics #universe #philosophy #fundamentalunits #theoryofeverything Sabine Hossenfelder is a theoretical physicist and acclaimed science communicator, known for her sharp critiques of the scientific mainstream. She is also a best-selling author and YouTuber. Ivette Fuentes is a theoretical quantum physicist at the University of Southampton and Emmy Fellow at the University of Oxford. James Ladyman is a philosopher of science at the University of Bristol. He is best known for his book Every Thing Must Go, calling for a metaphysics grounded in physics and complexity science. Hosted by Jack Symes. 00:40 James Ladyman on the different notions of scale 02:39 Sabine Hossenfelder on energy in the universe 05:19 Ivette Fuentes on unifying quantum mechanics and general relativity 09:00 Is the universe “One” or “Many”? 17:15 Particles are not fundamental The Institute of Art and Ideas features videos and articles from cutting edge thinkers discussing the ideas that are shaping the world, from metaphysics to string theory, technology to democracy, aesthetics to genetics. Subscribe today! https://iai.tv/subscribe?utm_source=Y… For debates and talks: https://iai.tv For articles: https://iai.tv/articles For courses: https://iai.tv/iai-academy/courses.

A central question in ancient Greek philosophy was the problem of the One and the Many. It is a question that has echoed across Western culture and is still with us today. Should we see the world as a coherent whole or a multitude of separate parts? The puzzle is that we need both the whole and the parts, but an explanation of the relationship between them has proved problematic and perhaps unknowable. In contemporary physics, the parts are the teeming world of particle physics, and these should make up the cosmological world of the universe as a whole and the overall framework of Einsteinian space-time. But as yet we have not been able to combine the two coherently.

Is looking at the universe from the small scale and the large always going to be incompatible? Does it mean a theory of everything is an illusion and the attempt to combine quantum mechanics and Einstein’s general relativity a forlorn project? Or is the parallel with the ancient Greek puzzle accidental and the current challenge one that might be overcome?

#quantumphysics #universe #philosophy #fundamentalunits #theoryofeverything.

Heisenberg Made a Discovery in 1925. We Still Can’t Explain It

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2025 is … was the international year of quantum science and technology. Yes because quantum tech is increasingly important, but especially because quantum mechanics was invented 100 years ago this year. In 1925, our strangest true theory went from being a peculiar set of ideas to describe some funny results from experiments, to a full-blown theoretical framework that overturned how we think reality really works. So today, as the centenary year approaches its end I want to take you on a little journey through what may be the most paradigm-destroying several months in scientific history.

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