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I want to know can QED can explain this image,like why there are someplaces with low light (shadows) like behind the chair, and why there are some places that are bright(rest of the floor).

I know that this depends on the scene that we are investigating but given a scene like the one in the image below,can QED explain why some places are bright and dark (shadows), or I have to use the classical model of light (Light travels in straight lines) to explain why some places are dark (shadows) and bright.

Like classical model of light can tell, light coming form the light source travels in straight lines and reaches the floor with no obstacles in between so they are more bright, and light behind the chair reaches after bouncing many times, so it has less energy and so the place behind the chair is not so bright.

Can QED explain this, that why some places are dark (behind the chair) and some bright (rest of the floor)?

enter image description here

Qmechanic
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Inder Gill
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1 Answers1

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Would you dig a ditch with a surgeons scalpel?

Yes, quantum mechanics ultimately underlies all physical observations but the mathematical expressions for large dimensions with respect to $\hbar$ become cumbersome and are replaced by the simplest ones for the appropriate study.

Thermodynamics, for the study of bulk matter, blends smoothly with quantum statistical mechanics, and for most engineering uses thermodynamics is by far the simplest and more useful mathematical tool.

Classical electrodynamics for the study of light, blends mathematically with quantum field theory, but its mathematical formulation is appropriate for the large numbers and dimensions we live and observe in.

See this link on how classical fields emerge from the underlying quantum mechanical framework.

DanielSank
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anna v
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