ON THE DETERMINATION OF CRITICAL POINT IN HIGHER-ORDER VARIATIONAL CUMULANT EXPANSION
1996 ◽
Vol 10
(12)
◽
pp. 531-536
◽
Keyword(s):
To the lowest order approximation, the method of variational cumulant expansion has been successful in the determination of the critical point of a spin system on the Ising model. In the second order calculation, unphysical phase transition arises. In this letter, we first analyze the origin of unphysical phase transitions in high-order variational cumulant expansion calculations. We then explain the basis on which a conjecture is proposed that to any order m of the variational cumulant expansion, the critical point is given by the bifurcation point of the free energy. The theory is finally verified numerically for the two-dimensional case.
2010 ◽
Vol 19
(08n09)
◽
pp. 1570-1576
Keyword(s):
1988 ◽
Vol 49
(C8)
◽
pp. C8-1387-C8-1388
2021 ◽
Vol 128
◽
pp. 114632
Keyword(s):
2014 ◽
Vol 16
(12)
◽
pp. 123044
◽
Keyword(s):
2015 ◽
pp. 882-895
◽
Keyword(s):
2003 ◽
Vol 14
(10)
◽
pp. 1305-1320
◽
2019 ◽
pp. 205-222
Keyword(s):
2020 ◽
Vol 34
(13)
◽
pp. 2050129
2000 ◽
Vol 10
(01)
◽
pp. 251-256
◽
Keyword(s):