Brain contains neural circuits (neuroclusters) which are responsible for modeling of the surrounding physical world. These neural circuits simulate the virtual copy of the real physical world.
The light bulb in a dream does not need "electricity" in order to shine, because it is just a model of the light bulb which is simulated by the cluster of neurons.
Neuroclusters in the brain usually store models of real-world-objects, however neuroclusters can also store models of non-real-world objects (a good example or non-real-world object is “chakras”).
Models of the objects can be copied from one human brain into another human brain in the similar way like computer files can be copied from one computer into another. The model of object X is copied from one human brain into another brain when man A tells to man B the features of object X, draws and shows the pictures of object X, makes statuette of object X and shows it, etc.
When two or more people have the same identical (or very similar) model of object X written in their brains – this phenomenon is called the “egregor X”.