I Information content in electromagnetic or gravitational waves

AI Thread Summary
Electromagnetic and gravitational waves carry energy and momentum, raising questions about their information content. If the energy dissipates as heat, the information may be lost, suggesting that observation is crucial for information existence. The discussion highlights the importance of defining information, particularly in the context of entropy and thermal equilibrium, where minimal information is present. Complete spectral information from wave signals, such as those from merging neutron stars, can provide significant insights into physical phenomena. The conversation emphasizes the relationship between energy, information, and the necessity of observation in understanding wave signals.
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Information scenerio in electromagnetic and gravitational waves. Conditions under which information content is lost.
Electromagnetic or gravitational wave carries energy and momentum from place to place as,I understand.Does it imply that such waves only can carry information and if their energy gets dissipated as heat, the information contained is lost.
Is this information content is to be decoded by human?
If there was no one to observe, was there any information?
Please discuss.
 
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Thank you very much anorlunda for valuable article. Will study it with care.
 
Of course, if all you measure is the total energy of a wave in terms of heat produced by it in a calorimeter all you have as information is this energy. Thermal equilibrium is the state of minimal information (in the sense of the Shannon-Jaynes interpretation of entropy as a measure for the missing information, which in the equilibrium state is maximal).

If you have of course, say, the complete spectral information of your wave signal you can learn a lot from it. E.g., from the gravitational-wave signals due to merging neutron stars (or a black-hole neutron-star merger) you can learn a lot about the equation of state of the strongly interacting matter making up the neutron star(s).
 
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