Signal Entropy: Any Change to the Carrier Creates Sidebands
Abstract
This paper explores an analogy between radio wave modulation and cosmological phenomena to illustrate complex concepts in physics. By comparing amplitude modulation (AM) to redshift/blueshift and frequency modulation (FM) to gravitational lensing, it provides a conceptual framework for understanding energy interactions and wave behavior in dynamic systems.
Introduction
Complex physical phenomena can often be better understood through relatable analogies. This paper presents a mind experiment that uses the principles of radio wave modulation to illustrate the intricacies of redshift, blueshift, and gravitational lensing.
Core Concept
The fundamental concept is the comparison of information transmission via radio waves to energy propagation in cosmological scenarios. In radio transmission, a signal is modulated onto a carrier frequency, occupying a specific portion of the electromagnetic spectrum. This modulation process generates sidebands—frequencies above and below the carrier frequency—which can be likened to how energy changes as it passes through varying conditions.
Discussion
Amplitude Modulation (AM) and Redshift/Blueshift: In AM, the sidebands of the carrier signal are analogous to its Fourier transforms, reflecting changes in the original signal’s characteristics as it interacts with the carrier signal. This is comparable to the production of redshift and blueshift sidebands when energy encounters variations in amplitude. Redshift and blueshift describe how the frequency (and wavelength) of light changes as the source and observer move relative to each other, or as light passes through a gravitational field.
Frequency Modulation (FM) and Gravitational Lensing: In FM, a multitude of sidebands is generated. This mirrors the complex effects observed during gravitational lensing, where the stretching and warping of waves around massive objects create a diverse spectrum. Gravitational lensing challenges the measurement of a single frequency due to the dynamic nature of gravitational interactions, particularly in regions dense with celestial bodies. The multiple sidebands in FM are analogous to the distorted and multiple images of distant objects produced by lensing.
Conclusion
This analogy between radio wave modulation and cosmological phenomena provides a valuable tool for conceptualizing complex physical processes. By drawing parallels between AM/FM and redshift/blueshift/gravitational lensing, we can gain a more intuitive understanding of how energy and waves behave in dynamic and complex systems.