Related Experiment Video
Updated: May 14, 2026
11:41
Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Twisted radio waves and twisted thermodynamics
Laszlo B Kish1, Robert D Nevels
1Solid State Electronics, Photonics, and Nanoengineering Division, Department of Electrical and Computer Engineering, Texas A&M University, College Station, Texas, United States of America. Laszlokish@tamu.edu
Plos One
|February 21, 2013
Summary
A thought experiment shows that transmitting many information channels via twisted wave modes from a single-frequency antenna violates thermodynamic laws. Therefore, transmitting numerous independent channels to the far field is impossible.
Area of Science:
- Electromagnetism
- Thermodynamics
- Information Theory
Background:
- Antennas are crucial for wireless communication, transmitting information via electromagnetic waves.
- The capacity of communication channels is a fundamental limit in information theory.
- Twisted wave modes, associated with orbital angular momentum, offer potential for increased channel capacity.
Purpose of the Study:
- To investigate the theoretical limits of information transmission from antennas.
- To determine if multiple independent information channels can be transmitted using twisted wave modes at a single frequency.
- To analyze the compatibility of such transmission with the Second Law of Thermodynamics.
Main Methods:
- A gedanken experiment (thought experiment) was designed and analyzed.
- The analysis focused on the principles of electromagnetism and thermodynamics.
- The study considered the transmission of independent information channels via orbital angular momentum modes.
Main Results:
- The assumption that a single-frequency antenna can transmit more than two independent information channels to the far field was shown to be invalid.
- Such transmission was found to violate the Second Law of Thermodynamics.
- The study demonstrates the impossibility of transmitting a large number of channels using twisted wave modes in free space.
Conclusions:
- The number of independent information channels that can be transmitted by an antenna at a single frequency is fundamentally limited.
- The Second Law of Thermodynamics imposes constraints on the capacity of free-space communication channels.
- Advanced transmission schemes, like using twisted wave modes, must adhere to these fundamental physical laws.
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