Non Standard Models

▶

▶ 15.2K ❤ 0 💬 0

Maryam Mirzakhani (1977-2017) was an Iranian mathematician and the first woman to ever win the prestigious Fields Medal. Her contribution to mathematics and to the fields of topology and geometry of Riemann surfaces in particular, can not be overstated. Here, Davide is drawing the so-called Mirzakhani recursion, a recursive technique to compute volumes of certain shapes associated to surfaces with boundaries and holes (like discs, etc). Quite surprisingly, these stunning results of imaginative mathematicians appear in physics as well! The unification of quantum field theory and gravity is one of the most challenging problems in modern theoretical physics. However, there exist some toy models where physicists can play with quantum effects of gravity at tiny scales. These simple models of quantum gravity are usually two-dimensional (1 time + 1 spatial dimensions), unlike our Universe, which is four-dimensional (1 time + 3 spatial dimensions). For these kind of theories, beautiful mathematics appears out of the geometry of spacetime and that’s exactly the mathematics of Maryam Mirzakhani. #mathematics #physics #theoreticalphysics #gravity #geometry #recursion #mirzakhani #fieldsmedal #phd #phdstudent #education #scicomm

▶

▶ 1.1K ❤ 0 💬 0

This is not at all a complete list so are there other problems that you find fascinating? ✨ Throughout the last century we understood a lot about our universe at the biggest and smallest scales, thanks to many physicists and mathematicians that one after the other developed tools to uncover the secrets of nature.  ‌Though there are still many open questions. Here are some of the most intriguing ones: -Quantum gravity: how do we quantize gravity meaning can we come up with a way to unify general relativity and quantum mechanics? -Black holes: what does it look like the inside of a bh? What happens when something falls inside of it? Where does the information go? -Dark matter: 26% of of universe is made of this mysterious type of matter? Is it a particle? Should we instead modify general relativity to account for it? -Dark energy: it composes 70% of our universe. What is this energy that is causing our universe to have an accelerated expansion? -Cosmological constant value: why there is such a big disagreement between the observed values of the vacuum energy density and the theoretical value suggested by quantum field theory? -Hierarchy problem: why is gravity is so weak compared to the other forces? What prevents quantities at the electroweak scale, such as the Higgs boson mass, from getting quantum corrections on the order of the Planck scale? -Color confinement: Quarks are the smallest components of the protons and neutrons constituting the nuclei of particles. Why can we only observe quarks confined inside the nuclei and not free? -Strong CP problem: The theory describing quarks called Quantum ChromoDynamics (QCD) should not be invariant under a combination of charge conjugation (C) and parity (P) but it is. Why? -Origin and destiny of the universe: How did the conditions for existence come about? Is the universe moving towards a Big Freeze, Big Rip, Big Crunch, or Big Bounce? Or is it part of an endlessly repeating cyclic model? #physics #theoreticalphysics #unsolved #questions #research #phd #phdstudent #scicomm #education

▶

▶ 1.8K ❤ 0 💬 0

What is a particle? A quantum mattress! In the introduction to his book on quantum field theory, physicist Anthony Zee explains how we can visualize the excitations or vibrations of quantum fields, namely particles, using a mattress. The vibrations of the mattress are just a collection of the vibrations of its springs. Now take an infinite and thick mattress that spans space and time, a quantum field, and its vibrations will be particles. All our Universe is then just tiny vibrations of everything everywhere all once! #physics #theoreticalphysics #quantumphysics #fields #quantum #particles #phd #phdstudent #research #education #scicomm