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

PO is now at the Physics Department of Bielefeld University!

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

205 submissions , 163 unreviewed
5,047 questions , 2,200 unanswered
5,345 answers , 22,709 comments
1,470 users with positive rep
816 active unimported users
More ...

  Proposed experimental cosiderations of a micro-mechanical oscilator in a superposition state

+ 0 like - 0 dislike
575 views

This question asks for the experimental result that is theoretically expected or is know already from experience, when one considers the following two scenarios for the micro-mechanical oscillator which can be put in an entangled quantum state with a qubit. See What exactly does Aaron D. O'Connell's experiment show?, for a basic theoretical overview.

Experimental Scenario-1

When the qubit and oscillator is in a coherent superposition of direct product states, we make an attempt to view the oscillator, which has dimensions only in the micrometer range, using a magnifying glass of high resolution, what do we see(or, if a similar operation has already been done, what was seen)? I know that for viewing the micro mechanical-oscillator using an optical device, we are required to irradiate the oscillator with visible radiation. But, I am not sure if that's always strong enough to break the coherence.

Experimental Scenario-2

This question also assumes the oscillator to be in the same state as that of the previous question. Consider a small massive bob, which is set up such that, any tiny changes in the gravitational field in it's immediate surrounding could be detected. It is assumed to be placed close to the micro-mechanical oscillator. Let this bob also be kept in an ultra-cold environment as the oscillator, so that one need not worry about environmental decoherence. In this context, we expect there to be a minuscule variation in the gravitational field experienced by the bob due to the varying distance between the bob and the center of mass of the oscillator. What does our measured value of gravitational field due to the oscillator look like as a function of time. Is it a smooth sine function?

Since these questions are experimental in nature, answers that are based on information about similar ideas that have been implemented in experiments of the past are appreciated more than speculations.

Note: In the first question, I am using the word 'see', as it's always in principle possible to observe a micro-meter sized object using an appropriate optical lens. To be more precise, let us say that we wish to see a tiny marking on the oscillator.

asked Jan 16, 2019 in Open problems by anonymous [ no revision ]

Before anyone gives an answer, let me mention a thought I had with regard to the second question. The following possibility appears to be ruled out: The measurement of gravitational field due to oscillator varies as a smooth function while at the same time the oscillator remains in the coherent superposition state, without assigning different physical meanings to 'vibration state of oscillator' in the context of gravitational field measurement and to the case in which the qubit-oscillator entangled system is subject to a measurement in the qubit's basis as was done in the original experiment.

Your answer

Please use answers only to (at least partly) answer questions. To comment, discuss, or ask for clarification, leave a comment instead.
To mask links under text, please type your text, highlight it, and click the "link" button. You can then enter your link URL.
Please consult the FAQ for as to how to format your post.
This is the answer box; if you want to write a comment instead, please use the 'add comment' button.
Live preview (may slow down editor)   Preview
Your name to display (optional):
Privacy: Your email address will only be used for sending these notifications.
Anti-spam verification:
If you are a human please identify the position of the character covered by the symbol $\varnothing$ in the following word:
p$\hbar$ysicsO$\varnothing$erflow
Then drag the red bullet below over the corresponding character of our banner. When you drop it there, the bullet changes to green (on slow internet connections after a few seconds).
Please complete the anti-spam verification




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

Your rights
...