Masao Hirokawa

Learn More
Introduction s Future real-world computational systems are x Complex • " Non-linear, " or • Undecomposable into " independent " modules x Open and adaptive to real world (i.e., to humans and/or natural systems) • Adaptive to unexpected inputs (in a short period of time) — humans and natural systems are unpredictable because autonomous and nondeterministic.(More)
In the Nelson model particles interact through a scalar massless field. For hydrogen-like atoms there is a nucleus of infinite mass and charge Ze, Z > 0, fixed at the origin and an electron of mass m and charge e. This system forms a bound state with binding energy E bin = me 4 Z 2 /2 to leading order in e. We investigate the radiative corrections to the(More)
We derive a mathematical mechanism of infrared catastrophe from the idea for the proof in [22, 23] and generalize it so that we can apply it to several models in quantum field theory. We define the Carleman operator from the operator-theoretical pull-through formula on ground states. Characterizing infrared catastrophe by the Carleman operator, we study the(More)
We consider two kinds of stability (under a perturbation) of the ground state of a self-adjoint operator, being concerned with (i) the sector to which the ground state belongs and (ii) the uniqueness of the ground state. As an application to the Wigner-Weisskopf model which describes one mode fermion coupled to a quantum scalar eld, we prove in the massive(More)
according to Part I of the By-Laws we announce a meeting of the IAMP General Assembly. It will convene on Monday August 3 in the Meridian Hall of the Clarion Congress Hotel in Prague opening at 8pm. The agenda: 1) President report 2) Treasurer report 3) The ICMP 2012 a) Presentation of the bids b) Discussion and informal vote 4) General discussion It is(More)
according to Part I of the By-Laws we announce a meeting of the IAMP General Assembly. It will convene on Monday August 3 in the Meridian Hall of the Clarion Congress Hotel in Prague opening at 8pm. The agenda: 1) President report 2) Treasurer report 3) The ICMP 2012 a) Presentation of the bids b) Discussion and informal vote 4) General discussion It is(More)