physics4me

physicsgg

Time-Energy Uncertainty Relation for a Quantum Clock as a Control Device

leave a comment »

A quantum clock working as a control device is examined. The quality of the control process is characterized by the magnitude of deviation of perturbed state from unperturbed state of the controlled system. Uncertainty relations that relate the time duration of the process and energy of the clock to the quality of the control are presented.

We read a clock to know what time it is. While time is a classical external parameter in the equation of motion, we need to observe a physical object called a clock to know the time of occurrence of a certain event. In quantum theory, dynamics of any physical object, including a clock, is governed by the Schr¨odinger equation. Following the pioneering work by Salecker and Wigner [1], several versions of the quantum clock have been proposed and analyzed [2, 3]. In particular, properties of quantum clocks have been investigated in the context of the time-energy uncertainty relation [4–8]. In addition to basic roles, Peres [2] argued that a clock can be employed to control the duration of perturbation on a system. Such control dynamics is often described by introducing a time-dependent perturbation….
Read more: http://arxiv.org/PS_cache/arxiv/pdf/1108/1108.3518v1.pdf

Written by physicsgg

August 18, 2011 at 8:11 am

Posted in QUANTUM PHYSICS

Tagged with

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: