  The superconducting transition in High Temperature Superconductors(HTS) has
not been understood. Traditional Bose Einstein Condensation(BEC) theory
provides Tc estimates that are many times higher than the experimental values.
The proposed model of Bounded Bose Einstein Condensation(BBEC) assumes that the
energy of a superconducting carrier in condensate is bounded by Fermi energy.
BBEC theory predicts Tc from the energetic balance that neglects any carrier
pairing term and assumes 3 dimensional (3D) superconducting transport in Low
Temperature Superconductors(LTS), and 2D superconducting transport channeled
near the nodes of the Fermi arcs in HTS. BBEC produces Tc scaling relations
that are approximated by semi-empirical laws, and provides Tc in agreement with
experimental data. This agreement in HTS shows the role of BBEC as the main
mechanism of superconducting transitions, indicates transport channeling
(possibly related to the stripes, and demonstrates a minor contribution into
the energetic balance from pairing or pairing above Tc (possibly related to the
pseudogap.
