"If you can explain this using common sense and logic, do let me know, because there is a Nobel Prize for you.." Professor Jim Al-Khalili explains the experiment that reveals the "central mystery of quantum mechanics" - the double slit experiment. Watch the full lecture here: http://www.youtube.com/watch?v=wwgQVZju1ZM Sometimes called the "two-slit" or "Young's" experiment, it demonstrates that matter and energy can display the characteristics of both waves and particles, establishing the principle known as wave-particle duality. Furthermore, it questions the role of the observer in the outcome of events and demonstrates the fundamental limitation of an observer to predict experimental results. For this reason, Richard Feynman called it "a phenomenon which is impossible ... to explain in any classical way, and which has in it the heart of quantum mechanics. In reality, it contains the only mystery [of quantum mechanics]," (see more at http://en.wikipedia.org/wiki/Double-slit_experiment). The Ri is on Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution Subscribe for the latest science videos: http://richannel.org/newsletter

Comments

1. Super!
2. Misleading title. Data presented without compatible model. Nonetheless caught a like. Thank you
3. When measuring something that tiny, our instruments use and deliver certain amounts of energy. When you measure the electron, you pour energy into it, increasing its vibration, frequency and mass. When you increase the mass of a quantum wave enough, it breaks the quantum/general relativity barrier, and it becomes a solid particle and behaves as such. Our measuring devices are the culprit, yet there's no current, or perhaps even practical way to measure the quantum state without altering it. Our instruments, that is. Not our "consciousness". The double slit is comprehensive enough. Entanglement, and to a lesser extent, superposition are both far more bizarre than the double slit experiments.
   
   I believe the Nobel is $1,000,000 and all the prestige and bragging rites a genius of my caliber is heir to?
4. That was 9 minutes of my life that I can never get back
5. is there a cut off size in the particles used in this experiment say from a tennis ball down to the atom/electron size when this dual nature of the particle as wave and particle starts to show in the two slit experiment?
6. If you remove the screen that the electrons eventually hit, all of the bands disappear
7. This is just simply a case of -- our photoreceptors or in this case, the scientists' being able to or better yet, NOT ABLE TO "catch up" to the particles which supposedly are faster than light.
   
   Unless we can invent a camera or detector that can FULLY record images that are faster than light, WHICH IS NOT POSSIBLE. Or repeat the experiment on another dimension (haha!)... scientists will never duplicate this wave-like property under active observation.
   
   P.S.
   - This is a solid evidence of the existence of other dimension/s.
   - Physical science at present, is only discernable to as much as the speed of light.
8. Common sense and logic. OBVIOUSLY we are looking at something that does not fit into materialism. Can we please dismiss those theories that do not work instead of trying to make them work with magical, unprovable multi-verses? We ALREADY HAVE the answer. It is just not the answer people like. We are not living in a material world. We live in a world designed to follow the rules of materialism, but if we look very closely, we find that it looks very much like a created world; not a simulation, not a video game, but a created world that exists in a much greater universe that follows rules we are not immediately able to perceive. The world we see around us does exist. It simply isn't all there is. There is a greater "realm" that our universe exists in. If we could discover the outer realm's rules, we would be able to account for all our failed ideas like "dark matter" and "dark energy" or our expanding universe accelerating apart, or why we have data at the root of all life, or why particles seem to behave like a "probability wave" or get entangled. It all starts to make perfect sense. It does also mean the research that so many of our smartest people have been working on for all their lives is futile. It also exposes our pride when we claim we have none.
   Yes, it is common sense that has been dismissed by the keepers of the torch in academia. If more science would be done into discovering this greater realm, maybe that torch could shed some light on the truth.
9. P.S. rational-common-sense logic says mass-energy-equivalence implies all particles are energy convolved on itself at the perpetual speed-of-light, in quanta stable by the general impedance properties of space (hot aether) and thus have mass by internal Doppler shift spreads and (or exclusively) systematic linear-kinetic wavelength going somewhere, Etc.
10. Everyone in the comments seems to think that the detector, in order to observe the light, must actively interfere with it somehow. If everyone knows this, why is the video not downvoted as pseudoscience?
11. A FULL METAPHYSICAL CURSE AND A HEX ON YOU JIM
12. CURSE YOU JIM
13. I THINK I'VE BEEN SWINDLED..
14. so if someone can solve this , there is a Nobel Prize waiting for them. By the way has anyone been able to solve this yet ? any Physicist yet , the date he solved and how he/she did it ? anyone ?
15. maybe the beep was clearing the energy so each atom started afresh.
16. It's easy to explain this "using common sense and logic" when you think using the "de broglie-bohm" interpretation and assume that the spy/observation is in fact interacting with the pilot-wave, thus causing the different behaviour.
17. This is the worst, low-brow explanation ever, shoving science back to the 18th century. Why not just call it magick?
18. Jim Al-Khalili>Brian Cox
19. Eureka...I have found it...It all comes down to the three states of matter. Gas, Liquid and Solid, as represented by the cloudy electron state, the wave form of protons and the solid state of neutrons. Each particle can be in one of these states and instantly changes from one to the other according to the influences upon them. When an electron is fired from the gun it is in a solid state which quickly changes to a wave-form but as soon as it touches a pressure-switch the electron reverts back to a solid state. It then passes through the slits before diffracting into a wave once again, but reverts back to solid immediately before hitting the back wall because it feels the pressure of the wall just before it strikes it. What the observation equipment does is send out a magnetic-field pressure switch across the path of the electron wave and so it remains solid right up to striking the back-wall...Can I claim my Nobel Prize now??
20. What is the nature of the detector? It could be that the detector itself is the cause of the disparity.