Jump to content
Sign in to follow this  
  • entries
  • comments
  • views

Quantum Physics is Weird



You wouldn't have too big a problem believing that the past can affect the future, or that the present affects the future. We see it everyday. But if I told you that the future could affect the past, you'd probably be a bit skeptical.

Quantum physics is full of these weird thought experiments that are absolutely wild and mind-bending, and one of them is known as Wheeler's delayed choice experiment (prominent in the late '70s and early '80s). John Wheeler attempted to answer a very strange question in the following way. It uses Young's double slit experiment wherein light can either demonstrate wave-like or particle-like properties.blogentry-1405-0-61094100-1429142876_thu

But light does not demonstrate these properties both at once, and Wheeler states that the light when passing through these slits "senses" the detection mechanism for either particles or waves, and adjusts accordingly. But by the time the detection mechanism is used/altered, the photons have already entered through the slit. So, is it possible that changing the detection mechanism after the light has already entered the slits affects how the light entered the slit in the first place?

This causality doesn't make much immediate sense, but then again, neither does a lot of stuff in quantum physics, and that's what makes it so enthralling, even though experiments such as this one have their detractors.

I myself am greatly struggling with understanding this, so if you're as confused as I am and care enough to do so, look into it! It's really cool stuff.


Recommended Comments

There are no comments to display.

Add a comment...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Terms of Use

The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.

Copyright Notice

APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to info@aplusphysics.com. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.

  • Create New...