It is generally agreed upon that electromagnetic waves from an emitter does not

Question

It is generally agreed upon that electromagnetic waves from an emitter does not have to connect to a receiver, but how can we be sure this is a fact? The problem is that we can never observe non received EM-Waves, because if we observe them the instrument of observation becomes a receiver.

Electromagnetic waves have changing electric and magnetic fields and are both electric and magnetic. Electric current connects like from an anode to a cathode. Magnetic fields illustrated by flux lines connect from one magnetic pole to another, and no non connecting flux lines are observed.

So electric currents connect and magnetic fields connect, so why doesn

Explanation / Answer

Richard Feynman's PhD thesis was about just this topic, if I am understanding your question rightly. Here is an earlier question about Feynman's thesis that addresses some of the fascinating issues involved with this.

At the suggestion of his thesis adviser John Wheeler, Feynman explained photon emission as a two-way interaction in which the regular photon is emitted and follows the "retarded" solutions to Maxwell's equations. "Meanwhile" (in some rather abstract sense of the word indeed) a target atom or particle in the distant future emits its own photon, but a very special one that travels backwards in time -- a type of solution to Maxwell's equations that had been recognized since Maxwell's time but had been ignored. These solutions were called the "advanced" solutions. This advanced photon travels back in time and "just happens" to arrive at the source at the exact instant when the regular photon is emitted, causing the emitting atom to be kicked backwards a tiny bit.

Amazingly, Wheeler and Feynman were able to write a series of papers showing that despite how mind-boggling this scenario sounded, it did not result in violations of causality, and it did provide a highly effective model of electron-photon interactions. From this start, and with some important changes, Feynman eventually produced his Feynman-diagram explanation of quantum electrodynamics, or QED. The curious time relationship continue in Feynman's QED, where for example a positron or anti-electron simply become an ordinary electron traveling backwards in time.

Staying fully consistent with his own ideas, Feynman himself described photon interactions as always having an emission and a reception event, no matter how far apart those events occur in ordinary time. In his view, if you shone a flashlight into deep space, the photons could not even be emitted until they found their "partner" advanced photon emission events somewhere in the distant future. The proof of it is in the very slight push back on your hand that happens when you shine the light, that kick coming from the advanced photons arriving from that distant point in the future and nudging the electrons in your flashlight filament.

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