https://youtu.be/cFslUSyfZPc | #AnInternet #TheoreticalPhysics

Of the four fundamental forces in nature only three – the electromagnetic force and the strong and weak nuclear forces – are explained by the #StandardModel of #ParticlePhysics.

The model can't explain the fourth fundamental force, #gravity, or #DarkMatter – a strange and mysterious substance thought to make up about 27% of the universe.

Scientists may be on brink of discovering fifth force of nature | #TheoreticalPhysics | The Guardian
https://www.theguardian.com/science/2023/aug/11/scientists-fifth-force-nature

#theoreticalphysics #particlephysics

I didn't include #introduction the first time. So, here goes again.

Recent late in life Dx #ActuallyAutistic #artist and #designer

Special interests in my bio plus these here:
• #LEGO
• #blender3d
• #RubiksCube
• #3Dprinting
• #JewelryDesign
• #drawing
• #DisneyWorld
• #geometry
• #TheoreticalPhysics
• #topology
• #EvolutionaryBiology
• #etymology
• #WebDesign
• #GraphicDesign
• #psychology
• #neurology
• #humor
• #nostalgia
• #engineering
• #technology

https://link.medium.com/X5InTdsgjzb
#physics #theoreticalphysics #quantumphysics

Wired: Researchers Argue Black Holes Will Destroy All Quantum States https://www.wired.com/story/black-holes-will-destroy-all-quantum-states/ #Tech #wired #TechNews #IT #Technology via @morganeogerbc #Science/PhysicsandMath #theoreticalphysics #QuantaMagazine #quantumphysics #WatchfulEye #blackholes #Astronomy #Science #physics #Gravity #space

#physics #theoreticalphysics I just realised that the integral over spacetime in the Dirac or Klein-Gordon action can be viewed as a contraction over the spacetime argument of the two scalar/spinor fields in the sense of contravariant/covariant index contraction. 🧵

"After losing his beloved father when he was 10, Ronald Mallett read HG Wells and Einstein. They inspired his eminent career as a theoretical physicist – and his lifelong ambition to build a time machine."

Back to the father: the scientist who lost his dad – and resolved to travel to 1955 to save him | #Science #TimeTravel #physics #theoreticalphysics | The Guardian https://www.theguardian.com/science/2023/mar/01/back-to-the-father-the-scientist-who-lost-his-dad-and-resolved-to-travel-to-1955-to-save-him

Is the question whether spacetime is real, or whether it's fundamental?

A blog post commenting on Matt O'Dowd's description of the developing doubt among physicists about whether spacetime is "real" or "fundamental".

#physics #PhilosophOfScience #philosophy #TheoreticalPhysics

https://selfawarepatterns.com/2023/02/26/is-the-question-whether-spacetime-is-real-or-whether-its-fundamental/

#physics #particlephysics #theoreticalphysics

”The most ordinary things are to philosophy a source of insoluble puzzles. With infinite ingenuity it constructs a concept of space or time and then finds it absolutely impossible that there be objects in this space or that processes occur during this time... the source of this kind of logic lies in excessive confidence in the so-called laws of thought.”

—Ludwig Boltzmann, Theoretical Physics and Philosophical Problems (1844-1906)

#philosophy #theoreticalphysics #LudwigBoltzmann

Interesting unpacking from Hossenfelder on the issues she has with particle physics.

But I'm not sure she herself is immune from the motivational issues she cites. For example, are her reasons for preferring hidden variable theories in QM really any different from the ones she's criticizing here?

To be fair, I doubt anyone really avoids these issues. Testing matters! And which tests to fund seems inevitably a judgment call.

https://www.youtube.com/watch?v=lu4mH3Hmw2o
#physics #TheoreticalPhysics #ParticlePhysics #quantum #QuantumFoundations

#Cats #Duvets #TheoreticalPhysics
A little #HistoryOfPhysics analogy: when antimatter was first suggested as a mathematical prediction (specifically the positron, a POSItive elecTRON) there was some discussion over whether it was a new particle, or just an *absence* of an electron in a field that was all electrons. A "hole" where an electron should be?
For example, is this an absence of a cat, or is it a negative cat?

How about some (theoretical) reality?

#Dirac, #Feynman and what to put in the #PathIntegral.

Very interesting and not too hard to follow.

https://www.quantamagazine.org/how-our-reality-may-be-a-sum-of-all-possible-realities-20230206/

#Physics #QuantumPhysics #TheoreticalPhysics #QuantaMagazine

#SoftMatter have just published the results of a project that Renato Assante, Davide Marenduzzo, Alexander Morozov, and I recently worked on together! What did we do and what’s new? Briefly…

#Microswimmer suspensions behave in a similar way to fluids containing kinesin and microtubules. Both systems can be described by the same system of three coupled nonlinear #PDEs.

A #LinearStabilityAnalysis of these equations suggests that variations in concentration across the system don’t significantly affect emergent #phaseBehaviour. How then can we explain #experiments that show visible inhomogeneities in #microtubule–#kinesin mixtures, for instance?

With increasing activity, we move away from the quiescent regime, past the onset of #SpontaneousFlow, and deeper into the active phase, where #nonlinearities become more important. What role do concentration inhomogeneities play here?

We investigated these questions, taking advantage of the #openSource #Dedalus #spectral framework to simulate the full nonlinear time evolution. This led us to predict a #novel regime of #spontaneous #microphaseSeparation into active (nematically ordered) and passive domains.

Active flow arrests macrophase separation in this regime, counteracting domain coarsening due to thermodynamic coupling between active matter concentration and #nematic order. As a result, domains reach a characteristic size that decreases with increasing activity.

This regime is one part of the #PhaseDiagram we mapped out. Along with our other findings, you can read all about it here!

low #ReynoldsNumber #turbulence #ActiveTurbulence #CahnHilliard #ActiveMatter #NavierStokes #BerisEdwards #CondensedMatter #PhaseTransitions #TheoreticalPhysics #BioPhysics #StatisticalPhysics #FluidDynamics #ComputationalPhysics #Simulation #FieldTheory #paperthread #NewPaper #science #research #ActiveGel #activeNematic #analytic #cytoskeleton #hydrodynamics #MPI #theory

#SoftMatter have just published the results of a project that Renato Assante, Davide Marenduzzo, Alexander Morozov, and I recently worked on together! What did we do and what’s new? Briefly…

The #hydrodynamic behaviour of inhomogeneous #activeNematic gels (such as extensile bundles of #cytoskeletal filaments or suspensions of low #ReynoldsNumber swimmers) can be described by the time evolution of three coupled #PDEs.

Standard #ActiveGel #theory concludes, from a #LinearStabilityAnalysis of these equations, that fluctuations in concentration don’t significantly affect emergent #phaseBehaviour. However, this leaves #experimental #observations of visible inhomogeneities in #microtubule–#kinesin mixtures unexplained. As we move away from the passive (quiescent) regime, past the onset of #SpontaneousFlow, and deeper into the active phase, #nonlinearities become more important. What role do concentration inhomogeneities play here?

Alongside #analytic techniques, we used an in-house #MPI-parallel code developed within the #Dedalus #spectral framework to investigate. We predict a #novel regime of #spontaneous #microphaseSeparation into active (nematically ordered) and passive domains. In this regime, active flow arrests macrophase separation, which is itself driven by the thermodynamic coupling between active matter concentration and #nematic order. As a result, domains do not #coarsen past a typical size, which decreases with increasing activity. This regime is one part of the #PhaseDiagram we mapped out.

Along with our other findings, you can read all about it here!

#CahnHilliard #ActiveMatter #NavierStokes #BerisEdwards #CondensedMatter #PhaseTransitions #TheoreticalPhysics #BioPhysics #StatisticalPhysics #FluidDynamics #ComputationalPhysics #Simulation #FieldTheory #paperthread #NewPaper #science #research

@empiricism That was my #theoreticalphysics answer. It may be interesting to ask: "Physicists, what to you think is at the very end of the world, and what's beyond! Please speculate!"

My own answer may be very different.

@empiricism Ok, that's a lot of aspects. Yes, my sphere is a "thought experiment". But my sphere exists theoretically (in some odd definition of "now"). However, the rocket will not reach the "crest", the "border" or whatever you may name it in my though experiment, says #theoreticalphysics.
In contrast, for your thought experiment #theoreticalphysics says nothing because of the single "faster than light" proposition.

@davidlrtb

"You are absolutely right! "

What? Then I definitely made an error somewhere.

"Sadly, no answer will be given.......Neither that you should not study physics and get proficient in #theoreticalphysics."

I have listened to many theoretical physicists discuss the subject (True). Plus I watched a Youtube video about it - so I now consider myself a world expert (another joke)

In science, it's OK to say "we don't know that! (yet?)"

However, it's not correct, and often hubris to say "we will never know that!". Some folks say "we will never know that!" as a form of pseudo-intellect-signaling - to suggest that they know, that we will never know that (and they don't know!). Basically, the same as OMG.

Ironically, psychology can also help in the study of theoretical physics.

@empiricism You are absolutely right!

And because of all of your arguments, the thought experiment is out of scope of #theoreticalphysics and #physics.

That means: even if your question is very interesting you can not find any answer in the realm of #physics. It's not that I'm not willing to give an answer. Neither that you should not study physics and get proficient in #theoreticalphysics. Sadly, no answer will be given.