Electron bands in the untwisted bilayer graphene flatten out in a transverse electric field, offering a promising platform for correlated electron physics. We predict that the spin/valley isospin magnetism, resembling that seen in moire bands, coexists with momentum-polarized phases occurring via a "flocking transition" in momentum space in which the electron distribution is spontaneously displaced in momentum space relative to the K or K valley centers. These phases feature unusual observables such as persistent currents in the ground state. Momentum-polarized carriers "sample" the Berry curvature of the conduction band, resulting in a unique behavior of the anomalous Hall conductivity and other effects that do not occur in previously studied systems.

Electron bands in Bernal-stacked (nontwisted) graphene bilayers in a transverse electric field feature field-tunable bandgaps and band dispersion that flattens out as the field increases. The effects of electron interactions are sharply enhanced in this regime, leading to a cascade of correlated phases exhibiting isospin (spin-valley) and momentum polarization orders. The momentum polarization, driven by exchange interactions, originates from a "flocking" effect, wherein all carriers condense into one, two or three pockets produced by the trigonal warping of the electron bands. The isospinpolarized phases mimic many aspects of the phases found in moiré graphene. The momentumpolarized phases, to the contrary, have symmetry lower than that of the isospin-polarized phases in moiré bands. We identify effects that can serve as probes of these orders, such as electronic nematicity, a B = 0 anomalous Hall response and orbital magnetization.

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