#PhysicsFactlet
I had to redo an old animation about quantum tunnelling in the time domain, so why not post it here?
#QuantumMechanics #ITeachPhysics
A few details:
* The incident and reflected waves interfere, creating fringes in the wavefunction modulus when it hits the barrier.
* Even when far away from the barrier, the wavefunction of the "free" particle is slowly broadening.
The United Nations has proclaimed 2025 the International Year of Quantum Science and Technology (IYQ).
At the @mpi_grav and the Institute for Gravitational Physics at @unihannover quantum mechanics has always played a major role in both experiment and theory.
We have put together a page for you that showcases our research related to quantum physics, associated press releases, relevant articles in yearbooks of the @maxplanckgesellschaft and, later during the year, current events.
Enjoy browsing 
https://www.aei.mpg.de/iyq2025
#science #theoreticalphysics #physics #time #spacetime #quantummechanics #reality #quantumentanglement #space #einstein #theories #fabricofreality
Just a bit of light reading regarding time and reality. I think New Scientist covers a similar thing in this month’s issue…
https://thequantuminsider.com/2024/05/20/quantum-entanglement-across-space-and-time-new-experiments-probe-the-limits/
So uh I think I may have found a clue how to solve quantum gravity. Or at the very least explain what exactly causes gravity.
I need an expert on that because I sure as heck ain't one.
I coded a quick and dirty simulation of it and it actually did end up up producing the predicted result. If there's nothing that makes it inapplicable there should be some merit to it but I lack the formal education to be able to judge.
I've just viewed a lecture from Carlo Rovelli, an Italian physicist, about the theories of TIME. It was a fascinating lecture to hear. Frankly, it all made sense and I can't wait to get hold of his book :The Order of Time.
#Physics #QuantumMechanics #NewtonianSpace #QuantumGravity #Neurology #SpecialRelativity #SpaceTime #ArrowOfTime
Microsoft deploys new state of matter in its first quantum computing chip
https://www.cnbc.com/2025/02/19/microsoft-reveals-its-first-quantum-computing-chip-the-majorana-1.html #quantum #quantumphysics #physics #science #quantummechanics #astrophysics
Please share: If you are interested in the foundations of Quantum Mechanics, there are now again a few slots open in our upcoming conference on the island of Helgoland, in June 2025. Celebrating 100 years of Quantum Mechanics!
General information: https://helgoland2025.yalepages.org/
Direct to registration: https://indico.mpl.mpg.de/event/17/registrations/
This conference has an illustrious list of speakers and panelists, including people like Alain Aspect, Anton Zeilinger, John Clauser, Serge Haroche, David Wineland, Michelle Simmons, and many many others.
https://www.europesays.com/1850921/ quantum mechanics: Study finds how new technology enhances gravitational-wave detection #america #AstroPhysics #BlackHoles #CosmicExplorer #GravitationalWaveDetection #LaserPower #LIGO #QuantumMechanics #science #technology #UnitedStates #UnitedStatesOfAmerica #US #USA
Juliane von Wrangel is a PhD student in the “10 m Prototype” group
Together with her colleagues she is building a 10-metre interferometer to overcome the fundamental limits of measurement accuracy imposed by quantum mechanics.
How Hans Bethe Stumbled Upon Perfect Quantum Theories
Quantum calculations amount to sophisticated estimates. But in 1931, Hans Bethe intuited precisely how a chain of particles would behave — an insight that had far-reaching consequences.
By Matt von Rippel
https://www.quantamagazine.org/how-hans-bethe-stumbled-upon-perfect-quantum-theories-20250212/
More information about Hans Bethe:
https://en.wikipedia.org/wiki/Hans_Bethe
The United Nations has proclaimed 2025 the International Year of Quantum Science and Technology (IYQ).
At the @mpi_grav and the Institute for Gravitational Physics at @unihannover quantum mechanics has always played a major role in both experiment and theory.
We have put together a page for you that showcases our research related to quantum physics, associated press releases, relevant articles in yearbooks of the @maxplanckgesellschaft and, later during the year, current events.
Enjoy browsing: https://www.aei.mpg.de/iyq2025
#PhysicsJournalClub
"The Tumultuous Birth of Quantum Mechanics"
by Philip Ball
https://physics.aps.org/articles/v18/24
"quantum mechanics wasn’t created all at once. It took several decades and was a messy, confused process, during most of which the true nature of this revolution was obscure. In some ways it still is."
The efficient conversion of #solar #energy into storable forms of #chemical energy is the dream of many engineers. Nature found a perfect solution to this problem billions of years ago. A new study shows that #quantum mechanics is not just for #physicists but also plays a key role in biology.
#QuantumScience #QuantumMechanics #Chemistry #Biology #sflorg
https://www.sflorg.com/2025/02/qs02042501.html
Quantum superposition used in a silicon chip for the first time - Earth.com
https://www.earth.com/news/schrodingers-cat-put-into-silicon-chip-may-be-holy-grail-for-error-proof-quantum-computing/ #quantum #quantumphysics #physics #science #quantummechanics #astrophysics
Physicists Found the Magic Number to Save Quantum Networks
https://scitechdaily.com/physicists-found-the-magic-number-to-save-quantum-networks/ #quantum #quantumphysics #physics #science #quantummechanics #astrophysics
Shedding Light on Quantum Measurement with Calcite - Have you ever struggled with the concept of quantum measurement, feeling it’s unne... - https://hackaday.com/2025/01/26/shedding-light-on-quantum-measurement-with-calcite/ #quantummeasurement #quantummechanics #entanglement #laserhacks #homehacks #science #calcite #photons #optics #light #news
Primordial black holes and dark matter, oh my! Hard SF writers will want to read this article.
https://phys.org/news/2025-01-gravitational-black-holes-quantum-effect.html
@orionkidder : if recollection serves me, this article will be of interest re one of your SF universes.
#PhysicsFactlet
Do you want an interpretation of quantum mechanics that doesn't really work that well in practice, but that would look fantastic for your Sci-Fi novel? I have for you "Many interacting words" (not to be confused with the similarly named "Many worlds interpretation").
In this interpretation the universe is 100% classical, but instead of being one universe there is a VERY large number of them, all classical and weakly interacting with each other. In particular each particle is classical, but is repelled by its "copies" in the other universes. This is able to replicate a lot of the most weird effects of quantum mechanics. For instance, classically a particle is not able to overcome a potential barrier if it doesn't have enough energy to do so, but in this interpretation the particle would be repelled by its copies, so it has a non-zero chance of getting enough of a kick to jump on the other side of the barrier, producing the phenomenon we usually call "quantum tunnelling".
Another effect replicated by this model is the "zero point energy" i.e. the fact that the lowest energy a particle can have is not zero, but a bit higher than that. In this interpretation this comes to be because the particle (which is classic) would like to sit at zero energy, but so do all of its "copies", and they repel, so none of them can really sit at zero energy.
If you want, in this interpretation the very fact we see quantum effects is evidence of parallel universes!
https://journals.aps.org/prx/abstract/10.1103/PhysRevX.4.041013
Superfast diamond-laced computer chips now much closer to reality thanks to 'quantum breakthrough'
https://www.livescience.com/technology/electronics/superfast-diamond-laced-computer-chips-now-much-closer-to-reality-thanks-to-quantum-breakthrough #quantum #quantumphysics #physics #science #quantummechanics #astrophysics
#PhysicsJournalClub
"Testing the necessity of complex numbers in traditional quantum theory with quantum computers"
by Jarrett L. Lancaster and Nicholas M. Palladino
Am. J. Phys. 93, 110 (2025)
In classical electrodynamics the use of complex numbers is only due to to its convenience for calculations. Nobody wants to remember all those pesky trigonometric identities, so we use complex numbers to simplify calculations and take the real part at the end. You need to be a bit careful when calculating stuff like the Poynting vector, but this is well addressed ion any half-decent undergrad-level textbook.
But for quantum mechanics the problem is less obvious. On one hand we only ever measure real quantities, but on the other hand the imaginary unit appears explicitly in the Schrödinger equation, and no textbook I am aware of ever even mention the possibility that quantum numbers might be just a calculation convenience like it is in classical electrodynamics.
The question is subtle enough that you are going to find no shortage of well-read Physicists claiming that it is "obvious" that complex numbers are necessary for quantum mechanics, or that it is "obvious" that you could just use real numbers if you wanted.
This paper makes a pretty good job at explaining the problem, going through some of the history and explicit calculations, up to constructing explicitly a real-valued version of QM.
The second part, where they make an "experiment" on a IBM cloud quantum computer is (imho) less interesting, and their conclusion that you need indeed complex numbers not really supported by the evidence, but your mileage might vary 
https://pubs.aip.org/aapt/ajp/article/93/1/110/3327097/Testing-the-necessity-of-complex-numbers-in
