Cosmic LibrarianBack to the drawing board...
Physicists Say We Were Completely Wrong About How Gravity Works
They've come up with a new "theory of everything."
Joe Heafner[2412.01551] Cosmology and general relativity (GR) in upper secondary school through new targeted teaching materials: a study on student learning and motivation #ITeachPhysics #Cosmology #GeneralRelativity #SecondarySchool
Cosmology and general relativity (GR) in upper secondary school through new targeted teaching materials: a study on student learning and motivation
Cosmology and GR remain largely inaccessible to high-school teaching due to the advanced prerequisites to master these topics. Integrating them into upper secondary teaching is a significant challenge that remains unresolved. This contribution reports on an implementation study of a GR and cosmology course for upper secondary school students as part of an educational project launched during the centenary of GR and tested ever since for several years. The course aimed to expand students' knowledge to include current physics topics while highlighting their foundations in areas of classical physics such as Newtonian mechanics, electromagnetism, and waves. Targeted teaching and learning materials are focused on conceptual and qualitative understanding, while systematically combined with a mathematical treatment accessible at the upper secondary level, avoiding oversimplification. A key element is an active learning approach, incorporating activities and tasks such as engaging applications related to current research, reflective exercises, thought experiments, and hands-on tasks. The main research objective was to explore whether a conceptually deep and educationally effective GR and cosmology course could be successfully implemented for non-specialist upper secondary students. A pre-post study assessed both conceptual learning and affective outcomes, including interest, curiosity, self-concept, and perceived relevance of science. Results showed encouraging gains in both learning and motivation, with large to very large effect sizes for conceptual learning of core principles. Additionally, no or small effects of predictors such as gender were observed. We conclude that the integration of GR and cosmology into upper secondary physics teaching, in the form of courses and materials that are engaging, comprehensible, and impactful, is feasible.
Daniel PomarèdeOn the cover of tomorrow's issue of Nature: predicting with high precision what happens when two black holes scatter.
José - Luis Gutiérrez Villanue🌌 Space and ⏳ time don’t just exist.
They bend.
Einstein showed us how.
And nothing has been the same since.
This video explains the mind-bending truth about gravity and the fabric of the universe 🧠✨
General Relativity & Curved Spacetime Explained! | Space Time | PBS Digital Studios
David QuinteroI was recommended enthusiastically the book "Essential Relativity" by Wolfgang Rindler. It seems quite complete and original in its exposition, although it avoids very advanced topics like the Kerr solution. Has anyone read it? #physics #generalrelativity
C.Unifying general relativity and the electromagnetic force? (I presume this also includes the weak nuclear force at sufficiently high energies, but this summary doesn't say)
https://phys.org/news/2025-04-einstein-field-theory.html
I'm pretty much at the limit of my understanding of field theories and such just in this summary article, I don't think I'll even try their full journal article.
@cenobyte - Does Professor Skye or her research assistant have any comment on the matter?
#relativity #GeneralRelativity #electromagnetic #force #field #TOE #GUT
Einstein's dream of a unified field theory accomplished?
During the latter part of the 20th century, string theory was put forward as a unifying theory of physics foundations. String theory has not, however, fulfilled expectations. That is why we are of the view that the scientific community needs to reconsider what comprises elementary forces and particles.
Gravity GrinchFresh from the @j824h_arXiv_astro_ph : calculating (numerically) the impact of a wave hitting a spherical overdensity in the cosmos, the wave suffers from a Shapiro delay and thus shows interference patterns. So do we really need fuzzy dark matter to observe interference?! https://arxiv.org/abs/2504.08286
#astronomy #GeneralRelativity #DarkMatter #Cosmology #Gravity
Numerical evolution of Maxwell's equations for wavefronts propagating through a spherical gravitational potential
We present a scheme for numerically solving Maxwell's equations in a weakly perturbed spacetime without introducing the usual geometric optics approximation. Using this scheme, we study light propagation through a spherical perturbation of a stationary metric in the linear limit. Going beyond geometric approximation allows us to explore the wave optics effects that occur when the wavefront propagates through the gravitational potential. We find that the wavefront breaks on the gravitational potential due to the Shapiro time delay, i.e. due to the slowing down of light when propagating in an inhomogeneous spacetime. This again leads to constructive interference, resulting in a persistent frequency dependent amplification of parts of the wave amplitude. When the wave length is shorter than a certain threshold set by the induced gravitational mass, the waves are reflected on the curvature gradient.
[2504.01675] Einstein's elevator and the principle of equivalence https://arxiv.org/abs/2504.01675
Einstein's elevator and the principle of equivalence
We outlines here the design, execution, and educational outcomes of an intervention inspired by Einstein's elevator thought experiment, intended to introduce secondary school students to the principle of equivalence, which is at the basis of the theory of General Relativity. We build an experimental version of Einstein's elevator, which simulated the effects of free-fall in an accelerated reference frame: a detailed description of the experimental apparatus and its construction is provided, highlighting the challenges and innovations in creating a simple yet functional setup using everyday materials.
Mark Tyndall#totp if you're in the right frame of reference (it would be a non-inertial one), then the sun does indeed go around the moon #GeneralRelativity
CosmicRamiWhooooaaaa! The new #JWST image is so good! So much physics going on — physics Einstein himself thought about!
This is called an Einstein Ring. When a massive foreground galaxy (in this case, an elliptical galaxy) warps the space-time around it, light from behind it bends in our direction.
The JWST caught this fantastic example, where the background spiral galaxy is getting warped into our view. It appears as a ring, but we can see its structures like its spiral arms, gas features and star clusters.
Incredible science happening here!
📸 ESA/Webb/NASA/CSA/G. Mahler
I added the annotations in the second image.
#astronomy #astrophysics #generalrelativity #galaxies #science #gravitationallens #Astrodon
