Exploring Planck Scale Dynamics in High Energy Physics

This presentation explores the Planck scale and mind-bending theories like superstring theory & loop quantum gravity that attempt to unify gravity with quantum mechanics!

1. Exploring Planck Scale Dynamics in High Energy Physics DEPARTMENT OF PHYSICS GOVT POST GRADUATE COLLEGE SWABI SYED SIRAJ UR RAHMAN Session (2019 – 2023) SYED SIRAJ UR RAHMAN Session (2019 – 2023)

2. Outlines Introduction Planck Scale Why study Planck scale? Theoretical Frameworks Experimental Methods Conclusion 2

3. Introduction Our current understanding of the universe relies on two prominent frameworks: Quantum Field Theory (QFT) QED, QCD, and QFD. General Relativity ( GR) However , these frameworks become incompatible at the Planck scale . When we combine GR with QFT they converge at the Planck scale. 3 Quantum Field Theory General Relativity Spacetime Geometry Matter and Energy Successful QFTs Q - Electrodynamics (Electromagnetic) Q - Flavordynamics (Weak) Q - Chromodynamics (Strong) The Standard Model of Particle Physics Gives Mass to Elementary Particles

4. Planck Scale Planck scale is based on ħ, G, c Planck l ength ~ √ħG/c³ ~ 10 -35 m Planck mass ~ √ħc/G ~ 10 -8 kg Planck t ime ~ √ħG/c⁵ ~ 10 -43 s Quantum gravitational effects are dominant at Planck scale. Quantum Fluctuations in Vacuum Due to Heisenberg Uncertainty Principle Fluctuations are much violent at small scales . E nergy density of a vacuum is 10 56 to 10 120 times larger than the observed amount. 4 Heisenberg Uncertainty Relations Quantum Vacuum

5. Why study Planck scale? Q-Gravity and TOE Spacetime Fabric Continuous ? (as GR predicts) Quantized ? (as QFT expects) Fluctuations (Q-Foam) Black Holes & Singularities ? Dark Matter ? Dark Energy ? Advanced Applications We want to go beyond the pico and femto technologies and quantum computing era. 5 Quantum Foam (Quantized Spacetime) Energy Distribution of the Universe Black Hole Simulation

6. Theoretical Frameworks These theoretical frameworks aim to reconcile General Relativity (GR) with Quantum Field Theory (QFT) , offering potential avenues for understanding the fundamental nature of the universe. Ongoing research continues to explore these models : Superstring/M Theory Loop Quantum Gravity (LQG) Emergence/E8 Theory Causal Dynamical Triangulations (CDT) The Holographic Principle 6

7. Superstring/M Theory Fundamental entities are tiny, vibrating strings . String Varieties (Open and Closed ) Particles correspond to different vibrational modes. + Supersymmetry Symmetry between fermions and bosons. Higher Dimensions (10 + 1) Gravity is weak because it leaks to higher dimensions. Predicts Graviton (Spin 2) Multiverse Calabi - Yau Manifold String Vibrations 7

8. Loop Quantum Gravity Spacetime fabric is considered as l oops (spin networks ) not continuous and smooth. Background Independent Theory Spacetime itself originated from these loop fluctuations. Loops are of the order of Planck scale Intense gravity would cause the loops to become incredibly and collapse to form a white hole that spells out matter. No singularities Gravitons (Maybe) Big Bounce 8 Quantum Foam Fluctuations Big Bounce

9. Emergence/E8 Theory Unifies all Interactions The basic units are called simplices ( T etrahedra ). Quasicrystal: Long range order but not periodic like regular crystals. E8 Lattice (8D Crystal) It has 240 vertices and accurately corresponds to all particles and forces in our (3D) reality and their interactions. Derived 3D quasicrystal is more complex. Research is ongoing 9 8D Crystal Represented here in 2D Tetrahedron Planck length

10. Experimental Methods Particle Colliders Planck energy ~ 10 19 GeV (Too Much) LHC (Not able to probe such small scale ) Future Circular Collider (FCC ) China: Planning about the largest collider in Future Event Horizon Telescope (EHT) Tests of Loop Quantum Gravity from the EHT Results of Sgr A * E8 Crystal (LQG) Quantum Gravity Research (Los Angeles ) Dark Energy Spectroscopic Instrument (DESI) Quantum Computing 10 Large Hadron Collider (CERN) E8 Crystal 3D Print

11. Conclusion Current Understanding: Based on general relativity and Quantum Theory. Challenges at the Planck Scale : Demands a quantum theory of gravity. Diverse Theoretical Frameworks : Superstring/M theory , loop quantum gravity, Emergence/E8 theory, and causal dynamical triangulations (CDT). Unique Challenges : Extremely high energies and small distances, dimensionality , s pacetime structure, s imulations, etc. Applications : Energy technologies, quantum computing, material science, medical technologies, space exploration. Research Ongoing Ultimate Goal: Theory of Everything (TOE) 11

12. THANKS! 12