Quantcast
  • Register
PhysicsOverflow is a next-generation academic platform for physicists and astronomers, including a community peer review system and a postgraduate-level discussion forum analogous to MathOverflow.

Welcome to PhysicsOverflow! PhysicsOverflow is an open platform for community peer review and graduate-level Physics discussion.

Please help promote PhysicsOverflow ads elsewhere if you like it.

News

New printer friendly PO pages!

Migration to Bielefeld University was successful!

Please vote for this year's PhysicsOverflow ads!

Please do help out in categorising submissions. Submit a paper to PhysicsOverflow!

... see more

Tools for paper authors

Submit paper
Claim Paper Authorship

Tools for SE users

Search User
Reclaim SE Account
Request Account Merger
Nativise imported posts
Claim post (deleted users)
Import SE post

Users whose questions have been imported from Physics Stack Exchange, Theoretical Physics Stack Exchange, or any other Stack Exchange site are kindly requested to reclaim their account and not to register as a new user.

Public \(\beta\) tools

Report a bug with a feature
Request a new functionality
404 page design
Send feedback

Attributions

(propose a free ad)

Site Statistics

145 submissions , 122 unreviewed
3,930 questions , 1,398 unanswered
4,851 answers , 20,619 comments
1,470 users with positive rep
501 active unimported users
More ...

Is it possible to build a Backward Time Viewer?

+ 0 like - 2 dislike
1099 views

As everyone knows, there are many doubts if backward time travel can be possible, since it raises many paradoxes of which the most known is probably the Grandfather paradox.

My question is the following: "According to the current state of our Physics knowledge, there is something that prevents us to build a Backward Time Viewer?".

By Backward Time Viewer I mean a machine which can display events occurring in an arbitrary date in the past (not necessarily in an arbitrary location). Clearly, this is not a precise definition, but I think is better to leave you some freedom to choose a precise definition as part of your answer.

I am not a physicist, but I thought that a Backward Time Viewer can be in contradiction with Heisenberg uncertainty principle in such a way: We measure with arbitrary precision the position of a particle at time 0. Then, at time 1, with a Backward Time Viewer we measure with arbitrary precision the velocity at time 0 of the particle. Thus we can obtain the position and velocity of the particle at time 0 with arbitrary precision, in constrast with the uncertainty principle.

Closed as per community consensus as the post is popular physics question
asked Nov 17, 2014 in Closed Questions by Charwe (-10 points) [ revision history ]
recategorized Jun 21, 2015 by Dilaton

Hi Charve,

PhysicsOverflow is a graduate-level and above physics site, which means that it is for advanced students and physicists. This seems rather a popular physics question, targeted at a general audience. I am therefore voting to close.

Hi Dilaton,

actually I do not see how my question is not of interest for graduate-level or above physicists. Surely, to understand the question itself are not required any graduate-level knowledges. However, I think that the problem is not trivial and that a precise answer needs deep knowledges of a large spectrum of Physics.

A "backward time viewer" could be consistent with the uncertainty principle, if it was restricted by the usual limits to precise measurement. For example, if accurately measuring the position of the particle now, made it impossible to measure its velocity in the future, using the viewer.




user contributions licensed under cc by-sa 3.0 with attribution required

Your rights
...