The history of physics is a fascinating journey of discovery, from early observations of the natural world to modern theories attempting to explain the universe in its entirety. Let me address your question in several parts, breaking down the evolution of physics, the medieval perspective on something like a mobile phone call, and your proposal about decoding past mobile calls using physical phenomena not yet understood.
1. Evolution of Knowledge in Physics
Physics has evolved through paradigms that reflect how humans have interpreted natural phenomena:
Antiquity: In ancient Greece, philosophers like Aristotle proposed ideas about motion and the structure of the cosmos based on qualitative observations. Their theories, while influential, lacked experimental rigor. For example, it was believed that objects fell at different speeds depending on their weight.
Middle Ages: During this period, physics was heavily influenced by religion and scholastic philosophy. Aristotelian ideas, adapted by the Church, dominated. Experimentation was limited, and phenomena were often explained in teleological terms (with a divine purpose). However, there were advances, such as Alhazen's studies on optics or the work of scholastics on motion (e.g., the Oxford school and the concept of "impetus").
Renaissance and Scientific Revolution (15th–17th centuries): With Copernicus, Galileo, and Newton, physics took a leap forward. Galileo introduced the experimental method, and Newton formulated the laws of motion and universal gravitation, laying the foundation for classical mechanics. Science began to rely on quantitative and mathematical observations.
18th–19th centuries: Classical physics expanded with the study of electromagnetism (Faraday, Maxwell), thermodynamics (Carnot, Clausius), and optics. Maxwell's equations unified electricity and magnetism, predicting electromagnetic waves, the basis for technologies like radio.
20th century: Einstein's relativity revolutionized our understanding of space, time, and gravity, while quantum mechanics (Planck, Bohr, Heisenberg) explained phenomena at atomic scales. These theories challenged classical intuition, introducing concepts like wave-particle duality and quantum entanglement.
21st century: Today, we explore unifying theories like string theory, quantum gravity, and phenomena such as dark matter and dark energy. Modern physics acknowledges that we don't understand all phenomena; gaps remain, such as reconciling general relativity with quantum mechanics.
2. Was a Mobile Phone Call Conceivable in the Middle Ages?
In the Middle Ages, the understanding of physics was limited to macroscopic observations and Aristotelian concepts. There was no knowledge of electromagnetic waves, electricity, or the principles enabling modern telecommunications. A mobile phone call requires:
Electromagnetic waves: Described by Maxwell in the 19th century, but unknown in the Middle Ages.
Electronics: Based on semiconductors, a 20th-century development.
Data encoding and transmission: Requiring knowledge of information theory (Shannon, 20th century).
For a medieval person, a mobile phone call would have been inconceivable within the framework of known physics. It might have been interpreted as magic or a miracle, as there were no concepts to explain the instantaneous transmission of voice over distance. Even the most advanced scholars, like Roger Bacon, who speculated about future technologies, could not have imagined something so specific without the theoretical foundations of electromagnetism or electronics.
3. Decoding Past Mobile Calls: Is It Possible?
Your proposal that we might one day decode past mobile phone calls raises a fascinating challenge. Let's analyze this from the perspective of current physics and the potential implications of yet-unknown phenomena:
Current Physics Perspective: According to known laws, the signals of a mobile phone call (electromagnetic waves) dissipate quickly in the environment. The energy of these waves scatters, is absorbed by materials, or gets lost in cosmic background noise. There is no known mechanism to "store" or "retrieve" these signals once emitted, unless they were recorded in a physical medium (e.g., a server). Thermodynamics (second law) and information theory suggest that recovering dissipated data is highly improbable, if not impossible, due to the increase in entropy. Additionally, causality (time flowing in one direction) implies we cannot access the past without violating fundamental principles like relativity.
Unknown Physical Phenomena: You suggest that current physics does not govern some phenomena that could make this possible. This is a valid possibility, as the history of physics shows that earlier paradigms were overtaken by new discoveries. Throughout history, what was considered impossible, magic, or science fiction—such as flying, communicating across distances, or exploring space—physics has gradually made possible through theoretical and technological advances. For example:
Quantum mechanics introduced non-intuitive phenomena like entanglement, which initially seemed impossible.
Speculative theories (e.g., wormholes, quantum retrocausality) suggest ways to interact with the past, though there's no experimental evidence.
There could be an unknown mechanism allowing the "capture" of dissipated information, perhaps a property of spacetime or an undiscovered field.
If a physical phenomenon existed that allowed decoding past signals, it would imply a radical shift in our understanding of time, information, and causality. For instance, it might require that information is never truly lost (as suggested by the holographic principle in black holes) or that spacetime stores data in some accessible form.
4. My Opinion
I don't rule out the possibility that unknown phenomena could enable things we currently deem impossible, like decoding past signals. The history of physics is full of examples where the "impossible" became possible with new knowledge (e.g., relativity challenged the notion of absolute time). However, with current physics, there's no evidence or plausible mechanism to achieve this. Your proposal would require a theoretical and experimental breakthrough that transcends our current laws, possibly related to the nature of time or information in the universe.
In summary, in the Middle Ages, a mobile phone call was unimaginable. Today, decoding past calls … seems impossible, but I cannot categorically claim it is, given that physics is an evolving field. What specific physical phenomenon do you imagine could enable this?