Why Time Travel Isn't As Impossible As You Think

Hey guys! We’re now live on Spotify🎧 Listen here: https://open.spotify.com/show/5rqQFYd... Every satellite over your head runs on a clock deliberately built to keep the wrong time, because up there time genuinely runs faster. One kind of time travel is already industrial. The other rests on three separate claims stacked inside a single word — and almost nobody has ever taken them apart. What is actually forbidden, and what did we only assume? A slow walk through the physics of the past: the exact solutions nobody wanted, the paradox that dissolved in 1991, and the conjecture that named itself one. Settle in and let this long, quiet walk through the physics of time keep you company tonight. Subscribe to Sundown Science if you like the questions that take two hours to ask properly. CHAPTERS 0:00 Introduction 1:31 The clock built wrong on purpose 11:38 What the word is carrying 17:59 The end of the universal now 29:01 The past as a place 41:18 The theorem nobody wrote 52:10 The paradox that isn't 1:01:51 What is left of the word 1:07:44 The fixed point that always exists 1:17:27 The past that has not finished 1:29:20 Influence that runs backward 1:40:18 The bill 1:50:48 The conjecture 2:01:06 Three claims, one left SOURCES Chronology protection conjecture (Hawking, Phys. Rev. D 46, 603) — https://journals.aps.org/prd/abstract... Quantum Field Theory on Spacetimes with a Compactly Generated Cauchy Horizon (Kay, Radzikowski & Wald) — https://arxiv.org/abs/gr-qc/9603012 Quantum mechanics near closed timelike lines (Deutsch, Phys. Rev. D 44, 3197) — https://link.aps.org/doi/10.1103/Phys... Billiard balls in wormhole spacetimes with closed timelike curves (Echeverria, Klinkhammer & Thorne, Phys. Rev. D 44, 1077) — https://link.aps.org/doi/10.1103/Phys... Experimental simulation of closed timelike curves (Ringbauer et al., Nature Communications 5, 4145) — https://www.nature.com/articles/ncomm... Wormholes, Time Machines, and the Weak Energy Condition (Morris, Thorne & Yurtsever, Phys. Rev. Lett. 61, 1446) — https://link.aps.org/doi/10.1103/Phys... An Example of a New Type of Cosmological Solutions of Einstein's Field Equations of Gravitation (Godel, Rev. Mod. Phys. 21, 447) — https://ui.adsabs.harvard.edu/abs/194... The warp drive: hyper-fast travel within general relativity (Alcubierre, Class. Quantum Grav. 11, L73) — https://iopscience.iop.org/article/10... Delayed "Choice" Quantum Eraser (Kim, Yu, Kulik, Shih & Scully, Phys. Rev. Lett. 84, 1) — https://link.aps.org/doi/10.1103/Phys... Experimental Realization of Wheeler's Delayed-Choice Gedanken Experiment (Jacques et al., Science 315, 966) — https://www.science.org/doi/10.1126/s... Wheeler's delayed-choice gedanken experiment with a single atom (Manning et al., Nature Physics 11, 539) — https://www.nature.com/articles/nphys... Is a time symmetric interpretation of quantum theory possible without retrocausality? (Leifer & Pusey, Proc. R. Soc. A 473) — https://royalsocietypublishing.org/rs... Around-the-World Atomic Clocks: Predicted Relativistic Time Gains (Hafele & Keating, Science 177, 166) — https://www.science.org/doi/10.1126/s... Resolving the gravitational redshift across a millimetre-scale atomic sample (Bothwell et al., Nature 602, 420) — https://www.nature.com/articles/s4158... Real-World Relativity: The GPS Navigation System (Ohio State University) — https://www.astronomy.ohio-state.edu/... — Disclaimer: All videos are produced for entertainment and education. Factual claims are sourced from peer-reviewed research and official scientific institutions. Where a video explores speculation, fringe theories, or the creator's own analysis, it is clearly labeled as such. Sundown Science is not a news outlet. Watch at your own discretion. #ClosedTimelikeCurves #ChronologyProtection