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Electromagnetic fields are quantized in manifestly covariant way by means ofa class of reducible representations of CCR. $A_a(x)$ transforms as a Hermitianfour-vector field in Minkowski four-position space (no change of gauge), but inmomentum space it splits into spin-1 massless photons (optics) and two masslessscalars (similar to dark matter). Unitary dynamics is given by point-forminteraction picture, with minimal-coupling Hamiltonian constructed from fieldsthat are free on the null-cone boundary of the Milne universe. SL(2,C)transformations and dynamics are represented unitarily in positive-norm Hilbertspace describing $N$ four-dimensional oscillators. Vacuum is a Bose-Einsteincondensate of the $N$-oscillator gas. Both the form of $A_a(x)$ and itstransformation properties are determined by an analogue of the twistorequation. The same equation guarantees that the subspace of vacuum states is,as a whole, Poincar\'e invariant. The formalism is tested on quantum fieldsproduced by pointlike classical sources. Photon statistics is well defined evenfor pointlike charges, with UV/IR regularizations occurring automatically as aconsequence of the formalism. The probabilities are not Poissonian but of aR\'enyi type with $\alpha=1-1/N$. The average number of photons occurring inBremsstrahlung splits into two parts: The one due to acceleration, and the onethat remains nonzero even if motion is inertial. Classical Maxwellelectrodynamics is reconstructed from coherent-state averaged solutions ofHeisenberg equations. Static pointlike charges polarize vacuum and produceeffective charge densities and fields whose form is sensitive to both thechoice of representation of CCR and the corresponding vacuum state.

Automatic regularization by quantization in reducible representations of CCR: Point-form quantum optics with classical sources