From: mk_thisisit
The concept of traveling at speeds greater than light, or faster-than-light (FTL), has been a significant topic of discussion in physics for decades [00:00:09] [00:00:21].
Apparent Faster-Than-Light Phenomena
While direct FTL travel for objects with mass is prohibited by Einstein’s theory of relativity, certain phenomena appear to exceed the speed of light:
- Expanding Space The oldest galaxies observed are moving away from us at speeds many times greater than the speed of light, as evidenced by their shift towards the infrared spectrum [00:00:30] [00:18:31]. This does not violate Einstein’s laws because it is space itself that is expanding at these higher speeds, not the objects moving through space [00:18:42] [00:18:47].
Historical Attempts and Misconceptions
Around a dozen years ago, there was considerable excitement about the possibility of achieving speeds greater than light [00:11:31] [00:12:22].
- OPERA Neutrino Anomaly An experiment between CERN and San Grasso involving neutrinos seemed to indicate they arrived slightly faster than light [00:12:27]. However, this was later identified as a technical error due to an incorrectly calculated length of optical fiber [00:12:37]. This incident reaffirmed that the laws of physics, specifically Einstein’s theory of relativity, still apply [00:12:11] [00:14:16].
Theoretical Approaches to Faster-Than-Light Travel
While direct FTL travel is not possible under current understanding, theoretical concepts offer potential avenues:
Wormholes and Spacetime Tunnels
- Theoretical Acceptance A few years ago, wormholes were considered purely theoretical objects, possibly existing but beyond human reach [00:01:17]. Today, physicists are more theoretically willing to accept that travel using space-time tunnels might be possible [00:01:30] [00:01:37].
- Connection to Quantum Entanglement A space-time tunnel formed from the merger of two black holes would require these black holes to be completely entangled [00:02:12] [00:03:00]. Entanglement is an inexplicable phenomenon where two particles behave consistently; if one changes its quantum state, the other will also change [00:02:28]. In laboratory conditions, particles must interact for entanglement to occur [00:02:47] [00:02:50].
- Stability and Challenges Historically, space-time tunnels were believed to be unstable, making passage impossible due to disruptions of time and space inside [00:03:09] [00:03:23]. However, recent progress in the quantum theory of the gravitational field suggests that with the right amount of information, the stability of entangled black holes could be maintained for passage [00:04:31] [00:04:47] [00:04:55]. Exiting from the other side remains beyond current civilization’s technical capabilities [00:04:57].
Quantum Computers
Quantum computers utilize the phenomenon of entanglement for error correction in experiments and theoretical models of quantum field theory and gravity [00:05:17]. This practical implementation of entanglement serves as an experimental testing ground before dreaming of traveling through space-time tunnels [00:05:57].
Conclusion
While exceeding the speed of light for physical objects remains elusive, the expansion of space itself and the theoretical possibilities offered by wormholes and quantum entanglement continue to be areas of active scientific inquiry. The progress in quantum theory and the development of quantum computing hint at potential future breakthroughs, even if direct FTL travel remains a distant dream [00:05:07] [00:19:14].