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t s rtrs t - - PowerPoint PPT Presentation
t s rtrs t s s sts str rst s
❇❛❝❦❣r♦✉♥❞
❚❤❡♦r❡♠ ✭❙✐♥❝❧❛✐r✕❚✉❧❧♦ ✶✾✼✹✮✳ ▲❡t A ❜❡ ❛ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡❛❝❤ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❚❡r♠✐♥♦❧♦❣② ❇❛♥❛❝❤ ❛❧❣❡❜r❛✿ ❛ ❝♦♠♣❧❡t❡ ♥♦r♠❡❞ ❛❧❣❡❜r❛✱ ✉s✉❛❧❧② ✉♥✐t❛❧✱ ❛❧✇❛②s ❤❛✈✐♥❣ ❝♦♠♣❧❡① s❝❛❧❛rs❀ ❧❡❢t ✐❞❡❛❧✿ ❛ ♥♦♥✲❡♠♣t② s✉❜s❡t ♦❢ s✉❝❤ t❤❛t ✐s
❝❧♦s❡❞ ✉♥❞❡r ❛❞❞✐t✐♦♥✿ ❛ ❜ ❛ ❜ ❝❧♦s❡❞ ✉♥❞❡r ❛r❜✐tr❛r② ❧❡❢t ♠✉❧t✐♣❧✐❝❛t✐♦♥✿ ❛❜ ❛ ❜
✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✿ t❤❡r❡ ❡①✐st ♥ ❛♥❞ ❜✶ ❜♥ s✉❝❤ t❤❛t ❛✶❜✶ ❛♥❜♥ ❛✶ ❛♥
✷
❇❛❝❦❣r♦✉♥❞
❚❤❡♦r❡♠ ✭❙✐♥❝❧❛✐r✕❚✉❧❧♦ ✶✾✼✹✮✳ ▲❡t A ❜❡ ❛ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡❛❝❤ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❚❡r♠✐♥♦❧♦❣②
◮ ❇❛♥❛❝❤ ❛❧❣❡❜r❛✿ ❛ ❝♦♠♣❧❡t❡ ♥♦r♠❡❞ ❛❧❣❡❜r❛✱ ✉s✉❛❧❧② ✉♥✐t❛❧✱ ❛❧✇❛②s ❤❛✈✐♥❣
❝♦♠♣❧❡① s❝❛❧❛rs❀ ❧❡❢t ✐❞❡❛❧✿ ❛ ♥♦♥✲❡♠♣t② s✉❜s❡t ♦❢ s✉❝❤ t❤❛t ✐s
❝❧♦s❡❞ ✉♥❞❡r ❛❞❞✐t✐♦♥✿ ❛ ❜ ❛ ❜ ❝❧♦s❡❞ ✉♥❞❡r ❛r❜✐tr❛r② ❧❡❢t ♠✉❧t✐♣❧✐❝❛t✐♦♥✿ ❛❜ ❛ ❜
✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✿ t❤❡r❡ ❡①✐st ♥ ❛♥❞ ❜✶ ❜♥ s✉❝❤ t❤❛t ❛✶❜✶ ❛♥❜♥ ❛✶ ❛♥
✷
❇❛❝❦❣r♦✉♥❞
❚❤❡♦r❡♠ ✭❙✐♥❝❧❛✐r✕❚✉❧❧♦ ✶✾✼✹✮✳ ▲❡t A ❜❡ ❛ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡❛❝❤ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❚❡r♠✐♥♦❧♦❣②
◮ ❇❛♥❛❝❤ ❛❧❣❡❜r❛✿ ❛ ❝♦♠♣❧❡t❡ ♥♦r♠❡❞ ❛❧❣❡❜r❛✱ ✉s✉❛❧❧② ✉♥✐t❛❧✱ ❛❧✇❛②s ❤❛✈✐♥❣
❝♦♠♣❧❡① s❝❛❧❛rs❀
◮ ❧❡❢t ✐❞❡❛❧✿ ❛ ♥♦♥✲❡♠♣t② s✉❜s❡t L ♦❢ A s✉❝❤ t❤❛t L ✐s
❝❧♦s❡❞ ✉♥❞❡r ❛❞❞✐t✐♦♥✿ ❛ ❜ ❛ ❜ ❝❧♦s❡❞ ✉♥❞❡r ❛r❜✐tr❛r② ❧❡❢t ♠✉❧t✐♣❧✐❝❛t✐♦♥✿ ❛❜ ❛ ❜
✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✿ t❤❡r❡ ❡①✐st ♥ ❛♥❞ ❜✶ ❜♥ s✉❝❤ t❤❛t ❛✶❜✶ ❛♥❜♥ ❛✶ ❛♥
✷
❇❛❝❦❣r♦✉♥❞
❚❤❡♦r❡♠ ✭❙✐♥❝❧❛✐r✕❚✉❧❧♦ ✶✾✼✹✮✳ ▲❡t A ❜❡ ❛ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡❛❝❤ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❚❡r♠✐♥♦❧♦❣②
◮ ❇❛♥❛❝❤ ❛❧❣❡❜r❛✿ ❛ ❝♦♠♣❧❡t❡ ♥♦r♠❡❞ ❛❧❣❡❜r❛✱ ✉s✉❛❧❧② ✉♥✐t❛❧✱ ❛❧✇❛②s ❤❛✈✐♥❣
❝♦♠♣❧❡① s❝❛❧❛rs❀
◮ ❧❡❢t ✐❞❡❛❧✿ ❛ ♥♦♥✲❡♠♣t② s✉❜s❡t L ♦❢ A s✉❝❤ t❤❛t L ✐s
◮ ❝❧♦s❡❞ ✉♥❞❡r ❛❞❞✐t✐♦♥✿ ❛ + ❜ ∈ L
(❛, ❜ ∈ L ); ❝❧♦s❡❞ ✉♥❞❡r ❛r❜✐tr❛r② ❧❡❢t ♠✉❧t✐♣❧✐❝❛t✐♦♥✿ ❛❜ ❛ ❜
✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✿ t❤❡r❡ ❡①✐st ♥ ❛♥❞ ❜✶ ❜♥ s✉❝❤ t❤❛t ❛✶❜✶ ❛♥❜♥ ❛✶ ❛♥
✷
❇❛❝❦❣r♦✉♥❞
❚❤❡♦r❡♠ ✭❙✐♥❝❧❛✐r✕❚✉❧❧♦ ✶✾✼✹✮✳ ▲❡t A ❜❡ ❛ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡❛❝❤ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❚❡r♠✐♥♦❧♦❣②
◮ ❇❛♥❛❝❤ ❛❧❣❡❜r❛✿ ❛ ❝♦♠♣❧❡t❡ ♥♦r♠❡❞ ❛❧❣❡❜r❛✱ ✉s✉❛❧❧② ✉♥✐t❛❧✱ ❛❧✇❛②s ❤❛✈✐♥❣
❝♦♠♣❧❡① s❝❛❧❛rs❀
◮ ❧❡❢t ✐❞❡❛❧✿ ❛ ♥♦♥✲❡♠♣t② s✉❜s❡t L ♦❢ A s✉❝❤ t❤❛t L ✐s
◮ ❝❧♦s❡❞ ✉♥❞❡r ❛❞❞✐t✐♦♥✿ ❛ + ❜ ∈ L
(❛, ❜ ∈ L );
◮ ❝❧♦s❡❞ ✉♥❞❡r ❛r❜✐tr❛r② ❧❡❢t ♠✉❧t✐♣❧✐❝❛t✐♦♥✿ ❛❜ ∈ L
(❛ ∈ A , ❜ ∈ L );
✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✿ t❤❡r❡ ❡①✐st ♥ ❛♥❞ ❜✶ ❜♥ s✉❝❤ t❤❛t ❛✶❜✶ ❛♥❜♥ ❛✶ ❛♥
✷
❇❛❝❦❣r♦✉♥❞
❚❤❡♦r❡♠ ✭❙✐♥❝❧❛✐r✕❚✉❧❧♦ ✶✾✼✹✮✳ ▲❡t A ❜❡ ❛ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡❛❝❤ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❚❡r♠✐♥♦❧♦❣②
◮ ❇❛♥❛❝❤ ❛❧❣❡❜r❛✿ ❛ ❝♦♠♣❧❡t❡ ♥♦r♠❡❞ ❛❧❣❡❜r❛✱ ✉s✉❛❧❧② ✉♥✐t❛❧✱ ❛❧✇❛②s ❤❛✈✐♥❣
❝♦♠♣❧❡① s❝❛❧❛rs❀
◮ ❧❡❢t ✐❞❡❛❧✿ ❛ ♥♦♥✲❡♠♣t② s✉❜s❡t L ♦❢ A s✉❝❤ t❤❛t L ✐s
◮ ❝❧♦s❡❞ ✉♥❞❡r ❛❞❞✐t✐♦♥✿ ❛ + ❜ ∈ L
(❛, ❜ ∈ L );
◮ ❝❧♦s❡❞ ✉♥❞❡r ❛r❜✐tr❛r② ❧❡❢t ♠✉❧t✐♣❧✐❝❛t✐♦♥✿ ❛❜ ∈ L
(❛ ∈ A , ❜ ∈ L );
◮ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✿ t❤❡r❡ ❡①✐st ♥ ∈ N ❛♥❞ ❜✶, . . . , ❜♥ ∈ L s✉❝❤ t❤❛t
L = {❛✶❜✶ + · · · + ❛♥❜♥ : ❛✶, . . . , ❛♥ ∈ A }.
✷
❚❤❡ ❉❛❧❡s✕➏❡❧❛③❦♦ ❝♦♥❥❡❝t✉r❡
❈♦♥❥❡❝t✉r❡ ✭❉❛❧❡s✕➏❡❧❛③❦♦ ✷✵✶✷✮✳ ▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡✈❡r② ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧✳ ❊✈✐❞❡♥❝❡✳ ❋❡rr❡✐r❛ ❛♥❞ ❚♦♠❛ss✐♥✐ ✭✶✾✼✽✮ ❤❛✈❡ ♣r♦✈❡❞ ❛ str♦♥❣❡r ❢♦r♠ ♦❢ t❤✐s ❝♦♥❥❡❝t✉r❡ ❢♦r ❝♦♠♠✉t❛t✐✈❡✳ ◆♦♥✲❝♦♠♠✉t❛t✐✈❡ ❝❛s❡✿ ♦♣❡♥✦ ◗✉❡st✐♦♥ ■✳ ■s t❤✐s ❝♦♥❥❡❝t✉r❡ tr✉❡ ❢♦r ❊ ✱ t❤❡ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ ♦❢ ❛❧❧ ❜♦✉♥❞❡❞✱ ❧✐♥❡❛r ♦♣❡r❛t♦rs ❛❝t✐♥❣ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊❄
✸
❚❤❡ ❉❛❧❡s✕➏❡❧❛③❦♦ ❝♦♥❥❡❝t✉r❡
❈♦♥❥❡❝t✉r❡ ✭❉❛❧❡s✕➏❡❧❛③❦♦ ✷✵✶✷✮✳ ▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡✈❡r② ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧✳ ❊✈✐❞❡♥❝❡✳ ❋❡rr❡✐r❛ ❛♥❞ ❚♦♠❛ss✐♥✐ ✭✶✾✼✽✮ ❤❛✈❡ ♣r♦✈❡❞ ❛ str♦♥❣❡r ❢♦r♠ ♦❢ t❤✐s ❝♦♥❥❡❝t✉r❡ ❢♦r A ❝♦♠♠✉t❛t✐✈❡✳ ◆♦♥✲❝♦♠♠✉t❛t✐✈❡ ❝❛s❡✿ ♦♣❡♥✦ ◗✉❡st✐♦♥ ■✳ ■s t❤✐s ❝♦♥❥❡❝t✉r❡ tr✉❡ ❢♦r ❊ ✱ t❤❡ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ ♦❢ ❛❧❧ ❜♦✉♥❞❡❞✱ ❧✐♥❡❛r ♦♣❡r❛t♦rs ❛❝t✐♥❣ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊❄
✸
❚❤❡ ❉❛❧❡s✕➏❡❧❛③❦♦ ❝♦♥❥❡❝t✉r❡
❈♦♥❥❡❝t✉r❡ ✭❉❛❧❡s✕➏❡❧❛③❦♦ ✷✵✶✷✮✳ ▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡✈❡r② ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧✳ ❊✈✐❞❡♥❝❡✳ ❋❡rr❡✐r❛ ❛♥❞ ❚♦♠❛ss✐♥✐ ✭✶✾✼✽✮ ❤❛✈❡ ♣r♦✈❡❞ ❛ str♦♥❣❡r ❢♦r♠ ♦❢ t❤✐s ❝♦♥❥❡❝t✉r❡ ❢♦r A ❝♦♠♠✉t❛t✐✈❡✳ ◆♦♥✲❝♦♠♠✉t❛t✐✈❡ ❝❛s❡✿ ♦♣❡♥✦ ◗✉❡st✐♦♥ ■✳ ■s t❤✐s ❝♦♥❥❡❝t✉r❡ tr✉❡ ❢♦r ❊ ✱ t❤❡ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ ♦❢ ❛❧❧ ❜♦✉♥❞❡❞✱ ❧✐♥❡❛r ♦♣❡r❛t♦rs ❛❝t✐♥❣ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊❄
✸
❚❤❡ ❉❛❧❡s✕➏❡❧❛③❦♦ ❝♦♥❥❡❝t✉r❡
❈♦♥❥❡❝t✉r❡ ✭❉❛❧❡s✕➏❡❧❛③❦♦ ✷✵✶✷✮✳ ▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ s✉❝❤ t❤❛t ❡✈❡r② ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✐s ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❤❡♥ A ✐s ✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧✳ ❊✈✐❞❡♥❝❡✳ ❋❡rr❡✐r❛ ❛♥❞ ❚♦♠❛ss✐♥✐ ✭✶✾✼✽✮ ❤❛✈❡ ♣r♦✈❡❞ ❛ str♦♥❣❡r ❢♦r♠ ♦❢ t❤✐s ❝♦♥❥❡❝t✉r❡ ❢♦r A ❝♦♠♠✉t❛t✐✈❡✳ ◆♦♥✲❝♦♠♠✉t❛t✐✈❡ ❝❛s❡✿ ♦♣❡♥✦ ◗✉❡st✐♦♥ ■✳ ■s t❤✐s ❝♦♥❥❡❝t✉r❡ tr✉❡ ❢♦r A = B(❊)✱ t❤❡ ❇❛♥❛❝❤ ❛❧❣❡❜r❛ ♦❢ ❛❧❧ ❜♦✉♥❞❡❞✱ ❧✐♥❡❛r ♦♣❡r❛t♦rs ❛❝t✐♥❣ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊❄
✸
❆ ♣❛rt✐❛❧ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ✇✐t❤ ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ✷c ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ❜✉t ♦♥❧② c ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ✇❤❡r❡ c = ✷ℵ✵✳ ❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥ ♦❢ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ❛ s❡q✉❡♥❝❡ ❊♥ ♥ ♦❢ ♥♦♥✲③❡r♦✱ ❝❧♦s❡❞ s✉❜s♣❛❝❡s ♦❢ ❊ s✉❝❤ t❤❛t✱ ❢♦r ❡❛❝❤ ① ❊✱ t❤❡r❡ ✐s ❛ ✉♥✐q✉❡ s❡q✉❡♥❝❡ ①♥ ✇✐t❤ ①♥ ❊♥ ♥ s✉❝❤ t❤❛t ①
♥ ✶
①♥ ✉♥❝♦♥❞✐t✐♦♥❛❧❧②✱ t❤❛t ✐s✱ t❤❡ ♥❡t
♥ ◆
①♥
◆ ✜♥✐t❡
❝♦♥✈❡r❣❡s t♦ ①✳ ❘❡♠❛r❦✳ ❚❤❡ ❛❜♦✈❡ t❤❡♦r❡♠ ❝❛♥ ❜❡ ❡①t❡♥❞❡❞ t♦ ♥♦♥✲s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✳
✹
❆ ♣❛rt✐❛❧ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ✇✐t❤ ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ✷c ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ❜✉t ♦♥❧② c ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ✇❤❡r❡ c = ✷ℵ✵✳ ❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥ ♦❢ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ❛ s❡q✉❡♥❝❡ ❊♥ ♥ ♦❢ ♥♦♥✲③❡r♦✱ ❝❧♦s❡❞ s✉❜s♣❛❝❡s ♦❢ ❊ s✉❝❤ t❤❛t✱ ❢♦r ❡❛❝❤ ① ❊✱ t❤❡r❡ ✐s ❛ ✉♥✐q✉❡ s❡q✉❡♥❝❡ ①♥ ✇✐t❤ ①♥ ❊♥ ♥ s✉❝❤ t❤❛t ①
♥ ✶
①♥ ✉♥❝♦♥❞✐t✐♦♥❛❧❧②✱ t❤❛t ✐s✱ t❤❡ ♥❡t
♥ ◆
①♥
◆ ✜♥✐t❡
❝♦♥✈❡r❣❡s t♦ ①✳ ❘❡♠❛r❦✳ ❚❤❡ ❛❜♦✈❡ t❤❡♦r❡♠ ❝❛♥ ❜❡ ❡①t❡♥❞❡❞ t♦ ♥♦♥✲s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✳
✹
❆ ♣❛rt✐❛❧ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ✇✐t❤ ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ✷c ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ❜✉t ♦♥❧② c ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ✇❤❡r❡ c = ✷ℵ✵✳ ❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥ ♦❢ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ❛ s❡q✉❡♥❝❡ (❊♥)♥∈N ♦❢ ♥♦♥✲③❡r♦✱ ❝❧♦s❡❞ s✉❜s♣❛❝❡s ♦❢ ❊ s✉❝❤ t❤❛t✱ ❢♦r ❡❛❝❤ ① ∈ ❊✱ t❤❡r❡ ✐s ❛ ✉♥✐q✉❡ s❡q✉❡♥❝❡ (①♥) ✇✐t❤ ①♥ ∈ ❊♥ (♥ ∈ N) s✉❝❤ t❤❛t ① =
∞
- ♥=✶
①♥ ✉♥❝♦♥❞✐t✐♦♥❛❧❧②✱ t❤❛t ✐s✱ t❤❡ ♥❡t
♥ ◆
①♥
◆ ✜♥✐t❡
❝♦♥✈❡r❣❡s t♦ ①✳ ❘❡♠❛r❦✳ ❚❤❡ ❛❜♦✈❡ t❤❡♦r❡♠ ❝❛♥ ❜❡ ❡①t❡♥❞❡❞ t♦ ♥♦♥✲s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✳
✹
❆ ♣❛rt✐❛❧ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ✇✐t❤ ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ✷c ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ❜✉t ♦♥❧② c ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ✇❤❡r❡ c = ✷ℵ✵✳ ❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥ ♦❢ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ❛ s❡q✉❡♥❝❡ (❊♥)♥∈N ♦❢ ♥♦♥✲③❡r♦✱ ❝❧♦s❡❞ s✉❜s♣❛❝❡s ♦❢ ❊ s✉❝❤ t❤❛t✱ ❢♦r ❡❛❝❤ ① ∈ ❊✱ t❤❡r❡ ✐s ❛ ✉♥✐q✉❡ s❡q✉❡♥❝❡ (①♥) ✇✐t❤ ①♥ ∈ ❊♥ (♥ ∈ N) s✉❝❤ t❤❛t ① =
∞
- ♥=✶
①♥ ✉♥❝♦♥❞✐t✐♦♥❛❧❧②✱ t❤❛t ✐s✱ t❤❡ ♥❡t
- ♥∈◆
①♥
- ◆⊂N ✜♥✐t❡
❝♦♥✈❡r❣❡s t♦ ①✳ ❘❡♠❛r❦✳ ❚❤❡ ❛❜♦✈❡ t❤❡♦r❡♠ ❝❛♥ ❜❡ ❡①t❡♥❞❡❞ t♦ ♥♦♥✲s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✳
✹
❆ ♣❛rt✐❛❧ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ✇✐t❤ ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ✷c ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ❜✉t ♦♥❧② c ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s✱ ✇❤❡r❡ c = ✷ℵ✵✳ ❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥ ♦❢ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ❛ s❡q✉❡♥❝❡ (❊♥)♥∈N ♦❢ ♥♦♥✲③❡r♦✱ ❝❧♦s❡❞ s✉❜s♣❛❝❡s ♦❢ ❊ s✉❝❤ t❤❛t✱ ❢♦r ❡❛❝❤ ① ∈ ❊✱ t❤❡r❡ ✐s ❛ ✉♥✐q✉❡ s❡q✉❡♥❝❡ (①♥) ✇✐t❤ ①♥ ∈ ❊♥ (♥ ∈ N) s✉❝❤ t❤❛t ① =
∞
- ♥=✶
①♥ ✉♥❝♦♥❞✐t✐♦♥❛❧❧②✱ t❤❛t ✐s✱ t❤❡ ♥❡t
- ♥∈◆
①♥
- ◆⊂N ✜♥✐t❡
❝♦♥✈❡r❣❡s t♦ ①✳ ❘❡♠❛r❦✳ ❚❤❡ ❛❜♦✈❡ t❤❡♦r❡♠ ❝❛♥ ❜❡ ❡①t❡♥❞❡❞ t♦ ♥♦♥✲s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✳
✹
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡ s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s
♣
✶ ♣ ❛♥❞ ❝✵ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣ ✵ ✶ ✶ ♣ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇ ♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼
♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶ ✵ ✶ t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s
♣
✶ ♣ ❛♥❞ ❝✵ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣ ✵ ✶ ✶ ♣ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇ ♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼
♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶ ✵ ✶ t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵;
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣ ✵ ✶ ✶ ♣ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇ ♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼
♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶ ✵ ✶ t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞);
t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇ ♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼
♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶ ✵ ✶ t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞); ◮ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇,♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼;
♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶ ✵ ✶ t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞); ◮ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇,♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼;
◮ ♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥
✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶ ✵ ✶ t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞); ◮ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇,♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼;
◮ ♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥
✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶[✵, ✶];
t❤❡ s♣❛❝❡ ❈ ❑ ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝ s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞); ◮ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇,♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼;
◮ ♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥
✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶[✵, ✶]; ◮ t❤❡ s♣❛❝❡ ❈(❑) ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝
s♣❛❝❡ ❑❀ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ ✶ ♣ ✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞); ◮ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇,♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼;
◮ ♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥
✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶[✵, ✶]; ◮ t❤❡ s♣❛❝❡ ❈(❑) ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝
s♣❛❝❡ ❑❀
◮ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ (✶ < ♣ < ∞)✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆♣♣❧✐❝❛t✐♦♥s ♦❢ t❤❡ t❤❡♦r❡♠
■♥ ❡❛❝❤ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ❝❛s❡s✱ t❤❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s s❡♣❛r❛❜❧❡ ❛♥❞ ❤❛s ❛ ❝♦✉♥t❛❜❧❡✱ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❞❡❝♦♠♣♦s✐t✐♦♥✿
◮ ❊ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s ✭t❤✐s ♠❡❛♥s t❤❛t ❡❛❝❤ ♦❢ t❤❡
s✉❜s♣❛❝❡s ❊♥ ❤❛s ❞✐♠❡♥s✐♦♥ ♦♥❡✮❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ❝❧❛ss✐❝❛❧ s❡q✉❡♥❝❡ s♣❛❝❡s ℓ♣ (✶ ♣ < ∞) ❛♥❞ ❝✵; ◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡s ▲♣[✵, ✶] (✶ < ♣ < ∞); ◮ t❤❡ ▲♦r❡♥t③ s❡q✉❡♥❝❡ s♣❛❝❡s ❞✇,♣ ❛♥❞ t❤❡ ❖r❧✐❝③ s❡q✉❡♥❝❡ s♣❛❝❡s ❤▼;
◮ ♠♦r❡ ❣❡♥❡r❛❧❧②✱ ❊ ❝♦♥t❛✐♥s ❛ ❝♦♠♣❧❡♠❡♥t❡❞ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥
✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ❡①❛♠♣❧❡s✿
◮ t❤❡ ▲❡❜❡s❣✉❡ s♣❛❝❡ ▲✶[✵, ✶]; ◮ t❤❡ s♣❛❝❡ ❈(❑) ♦❢ ❝♦♥t✐♥✉♦✉s ❢✉♥❝t✐♦♥s ♦♥ ❛♥ ✐♥✜♥✐t❡✱ ❝♦♠♣❛❝t ♠❡tr✐❝
s♣❛❝❡ ❑❀
◮ t❤❡ ♣t❤ q✉❛s✐✲r❡✢❡①✐✈❡ ❏❛♠❡s s♣❛❝❡ ❏♣ (✶ < ♣ < ∞)✳
❍❡♥❝❡ ♥♦t ❛❧❧ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊) ❛r❡ ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ✐♥ ❡❛❝❤ ♦❢ t❤❡ ❛❜♦✈❡ ❝❛s❡s✳ P❡rs♣❡❝t✐✈❡✳ ●♦✇❡rs✬s ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠✿ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡ ✐s ❡✐t❤❡r ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ♥♦♥❡ ♦❢ ✐ts ❝❧♦s❡❞ s✉❜s♣❛❝❡s ❝❛♥ ❜❡ ❞❡❝♦♠♣♦s❡❞ ✐♥t♦ t❤❡ ❞✐r❡❝t s✉♠ ♦❢ t✇♦ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲ ❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡s✮✱ ♦r ✐t ❝♦♥t❛✐♥s ❛ s✉❜s♣❛❝❡ ✇❤✐❝❤ ❤❛s ❛♥ ✉♥❝♦♥❞✐t✐♦♥❛❧ ❙❝❤❛✉❞❡r ❜❛s✐s✳
✺
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ ①✳ ▼♦r❡♦✈❡r✱
① ②
① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ ① ② ❊ ✵ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠
① ❢♦r s♦♠❡ ①
❊ ✵ ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ ❚ ❊ ❋ ❦❡r ❚ ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱
① ②
① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ ① ② ❊ ✵ ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠
① ❢♦r s♦♠❡ ①
❊ ✵ ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ ❚ ❊ ❋ ❦❡r ❚ ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠
① ❢♦r s♦♠❡ ①
❊ ✵ ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ ❚ ❊ ❋ ❦❡r ❚ ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠ ML ① ❢♦r s♦♠❡ ① ∈ ❊ \ {✵} ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ ❚ ❊ ❋ ❦❡r ❚ ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠ ML ① ❢♦r s♦♠❡ ① ∈ ❊ \ {✵} ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ ❚ ❊ ❋ ❦❡r ❚ ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠ ML ① ❢♦r s♦♠❡ ① ∈ ❊ \ {✵} ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ ❚ ❊ ❋ ❦❡r ❚ ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠ ML ① ❢♦r s♦♠❡ ① ∈ ❊ \ {✵} ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ → {❚ ∈ B(❊) : ❋ ⊆ ❦❡r ❚} ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠ ML ① ❢♦r s♦♠❡ ① ∈ ❊ \ {✵} ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ → {❚ ∈ B(❊) : ❋ ⊆ ❦❡r ❚} ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊) ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ ✐s ✜①❡❞✳
✻
❆ r❡✜♥❡♠❡♥t ♦❢ t❤❡ q✉❡st✐♦♥
❖❜s❡r✈❛t✐♦♥✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡✳ ❋♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✱ ML ① = {❚ ∈ B(❊) : ❚① = ✵} ✐s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ❣❡♥❡r❛t❡❞ ❜② t❤❡ s✐♥❣❧❡ ♣r♦❥❡❝t✐♦♥ ■ − P✱ ✇❤❡r❡ P ✐s ❛♥② ♣r♦❥❡❝t✐♦♥ ♦❢ ❊ ♦♥t♦ C①✳ ▼♦r❡♦✈❡r✱ ML ① = ML ② ⇐ ⇒ ① ❛♥❞ ② ❛r❡ ♣r♦♣♦rt✐♦♥❛❧ (①, ② ∈ ❊ \ {✵}). ❚❡r♠✐♥♦❧♦❣②✳ ❆ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ t❤❡ ❢♦r♠ ML ① ❢♦r s♦♠❡ ① ∈ ❊ \ {✵} ✐s ✜①❡❞✳ ◗✉❡st✐♦♥ ■■✳ ■s ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✜①❡❞❄ ❋❛❝t✳ ❚❤✐s ✐s tr✉❡ ❢♦r ❊ ✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ Pr♦♦❢✳ ❚❤❡ ♠❛♣♣✐♥❣ ❋ → {❚ ∈ B(❊) : ❋ ⊆ ❦❡r ❚} ✐s ❛♥ ❛♥t✐✲✐s♦♠♦r♣❤✐s♠ ♦❢ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧✐♥❡❛r s✉❜s♣❛❝❡s ♦❢ ❊ ♦♥t♦ t❤❡ ❧❛tt✐❝❡ ♦❢ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✳ ❍❡♥❝❡ ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊) ❝♦rr❡s♣♦♥❞s t♦ ❛ ✉♥✐q✉❡ ♦♥❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊✱ ❛♥❞ t❤❡r❡❢♦r❡ L ✐s ✜①❡❞✳ ✷
✻
◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ ❊ ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✳ ❋❛❝t✳ ❊
① ❢♦r ❡❛❝❤ ①
❊ ✵ ✳ Pr♦♦❢✳ ●✐✈❡♥ ① ❊ ✵ ✱ t❛❦❡ ❊ s✉❝❤ t❤❛t ① ✶✳ ❚❤❡♥ ❚ ② ② ① ❊ ❊ ❜❡❧♦♥❣s t♦ ❊ ✱ ❜✉t ♥♦t t♦
① ❜❡❝❛✉s❡ ❚①
① ✵✳ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
✼
◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ ❊
① ❢♦r ❡❛❝❤ ①
❊ ✵ ✳ Pr♦♦❢✳ ●✐✈❡♥ ① ❊ ✵ ✱ t❛❦❡ ❊ s✉❝❤ t❤❛t ① ✶✳ ❚❤❡♥ ❚ ② ② ① ❊ ❊ ❜❡❧♦♥❣s t♦ ❊ ✱ ❜✉t ♥♦t t♦
① ❜❡❝❛✉s❡ ❚①
① ✵✳ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
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◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ❊ ✵ ✱ t❛❦❡ ❊ s✉❝❤ t❤❛t ① ✶✳ ❚❤❡♥ ❚ ② ② ① ❊ ❊ ❜❡❧♦♥❣s t♦ ❊ ✱ ❜✉t ♥♦t t♦
① ❜❡❝❛✉s❡ ❚①
① ✵✳ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
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◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ∈ ❊ \ {✵}✱ t❛❦❡ λ ∈ ❊ ∗ s✉❝❤ t❤❛t ①, λ = ✶✳ ❚❤❡♥ ❚ ② ② ① ❊ ❊ ❜❡❧♦♥❣s t♦ ❊ ✱ ❜✉t ♥♦t t♦
① ❜❡❝❛✉s❡ ❚①
① ✵✳ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
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◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ∈ ❊ \ {✵}✱ t❛❦❡ λ ∈ ❊ ∗ s✉❝❤ t❤❛t ①, λ = ✶✳ ❚❤❡♥ ❚ : ② → ②, λ①, ❊ → ❊, ❜❡❧♦♥❣s t♦ F(❊)✱ ❜✉t ♥♦t t♦
① ❜❡❝❛✉s❡ ❚①
① ✵✳ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
✼
◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ∈ ❊ \ {✵}✱ t❛❦❡ λ ∈ ❊ ∗ s✉❝❤ t❤❛t ①, λ = ✶✳ ❚❤❡♥ ❚ : ② → ②, λ①, ❊ → ❊, ❜❡❧♦♥❣s t♦ F(❊)✱ ❜✉t ♥♦t t♦ ML ① ❜❡❝❛✉s❡ ❚① = ① = ✵✳ ✷ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
✼
◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ∈ ❊ \ {✵}✱ t❛❦❡ λ ∈ ❊ ∗ s✉❝❤ t❤❛t ①, λ = ✶✳ ❚❤❡♥ ❚ : ② → ②, λ①, ❊ → ❊, ❜❡❧♦♥❣s t♦ F(❊)✱ ❜✉t ♥♦t t♦ ML ① ❜❡❝❛✉s❡ ❚① = ① = ✵✳ ✷ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞✳ ❚❤❡♥ ❊ ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
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◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ∈ ❊ \ {✵}✱ t❛❦❡ λ ∈ ❊ ∗ s✉❝❤ t❤❛t ①, λ = ✶✳ ❚❤❡♥ ❚ : ② → ②, λ①, ❊ → ❊, ❜❡❧♦♥❣s t♦ F(❊)✱ ❜✉t ♥♦t t♦ ML ① ❜❡❝❛✉s❡ ❚① = ① = ✵✳ ✷ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s ❊ ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❄
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◗✉❡st✐♦♥ ■■ ✖ t❤❡ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❝❛s❡
▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥ F(❊) = {❚ ∈ B(❊) : ❞✐♠ ❚(❊) < ∞} ✐s ❛ ♣r♦♣❡r✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ F(❊) ✐s ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❋❛❝t✳ F(❊) ⊆ ML ① ❢♦r ❡❛❝❤ ① ∈ ❊ \ {✵}✳ Pr♦♦❢✳ ●✐✈❡♥ ① ∈ ❊ \ {✵}✱ t❛❦❡ λ ∈ ❊ ∗ s✉❝❤ t❤❛t ①, λ = ✶✳ ❚❤❡♥ ❚ : ② → ②, λ①, ❊ → ❊, ❜❡❧♦♥❣s t♦ F(❊)✱ ❜✉t ♥♦t t♦ ML ① ❜❡❝❛✉s❡ ❚① = ① = ✵✳ ✷ ❈♦r♦❧❧❛r②✳ ❆ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■ ✐♠♣❧✐❡s ❛ ♣♦s✐t✐✈❡ ❛♥s✇❡r t♦ ◗✳ ■✿ ▲❡t ❊ ❜❡ ❛♥ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ ❇❛♥❛❝❤ s♣❛❝❡✱ ❛♥❞ s✉♣♣♦s❡ t❤❛t ❡✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❚❤❡♥ B(❊) ❝♦♥t❛✐♥s ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ✇❤✐❝❤ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞✳ ◗✉❡st✐♦♥ ■■■✳ ■s F(❊) ❡✈❡r ❝♦♥t❛✐♥❡❞ ✐♥ ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)❄
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❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠
❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❚ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ■ − ❙❚ ✐s ❛ ❋r❡❞❤♦❧♠ ♦♣❡r❛t♦r✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❞✐♠ ❦❡r(■ − ❙❚) < ∞ ❛♥❞ ❞✐♠ ❊ (■ − ❙❚)(❊) < ∞, ❢♦r ❡❛❝❤ ❙ ∈ B(❊)✳ ❚❤❡ s❡t ❊ ♦❢ ✐♥❡ss❡♥t✐❛❧ ♦♣❡r❛t♦rs ♦♥ ❊ ✐s ❛ ❝❧♦s❡❞✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❊ ✱ ❛♥❞ ♣r♦♣❡r ✇❤❡♥❡✈❡r ❊ ✐s ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❆♥ ❡q✉✐✈❛❧❡♥t✱ ♠♦r❡ ❛❧❣❡❜r❛✐❝✱ ❞❡✜♥✐t✐♦♥ ✐s t❤❛t ❚ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ❚ ❊ ❜❡❧♦♥❣s t♦ t❤❡ ❏❛❝♦❜s♦♥ r❛❞✐❝❛❧ ♦❢ t❤❡ ❈❛❧❦✐♥ ❛❧❣❡❜r❛ ❊ ❊ ✳ ❊①❛♠♣❧❡✳ ❆ ❍✐❧❜❡rt✲s♣❛❝❡ ♦♣❡r❛t♦r ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐t ✐s ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ ✐s ✜①❡❞❀ ♦r ✭✐✐✮ ❝♦♥t❛✐♥s ❊ ✳
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❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠
❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❚ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ■ − ❙❚ ✐s ❛ ❋r❡❞❤♦❧♠ ♦♣❡r❛t♦r✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❞✐♠ ❦❡r(■ − ❙❚) < ∞ ❛♥❞ ❞✐♠ ❊ (■ − ❙❚)(❊) < ∞, ❢♦r ❡❛❝❤ ❙ ∈ B(❊)✳ ❚❤❡ s❡t E (❊) ♦❢ ✐♥❡ss❡♥t✐❛❧ ♦♣❡r❛t♦rs ♦♥ ❊ ✐s ❛ ❝❧♦s❡❞✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ❛♥❞ ♣r♦♣❡r ✇❤❡♥❡✈❡r ❊ ✐s ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❆♥ ❡q✉✐✈❛❧❡♥t✱ ♠♦r❡ ❛❧❣❡❜r❛✐❝✱ ❞❡✜♥✐t✐♦♥ ✐s t❤❛t ❚ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ❚ ❊ ❜❡❧♦♥❣s t♦ t❤❡ ❏❛❝♦❜s♦♥ r❛❞✐❝❛❧ ♦❢ t❤❡ ❈❛❧❦✐♥ ❛❧❣❡❜r❛ ❊ ❊ ✳ ❊①❛♠♣❧❡✳ ❆ ❍✐❧❜❡rt✲s♣❛❝❡ ♦♣❡r❛t♦r ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐t ✐s ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ ✐s ✜①❡❞❀ ♦r ✭✐✐✮ ❝♦♥t❛✐♥s ❊ ✳
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❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠
❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❚ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ■ − ❙❚ ✐s ❛ ❋r❡❞❤♦❧♠ ♦♣❡r❛t♦r✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❞✐♠ ❦❡r(■ − ❙❚) < ∞ ❛♥❞ ❞✐♠ ❊ (■ − ❙❚)(❊) < ∞, ❢♦r ❡❛❝❤ ❙ ∈ B(❊)✳ ❚❤❡ s❡t E (❊) ♦❢ ✐♥❡ss❡♥t✐❛❧ ♦♣❡r❛t♦rs ♦♥ ❊ ✐s ❛ ❝❧♦s❡❞✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ❛♥❞ ♣r♦♣❡r ✇❤❡♥❡✈❡r ❊ ✐s ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❆♥ ❡q✉✐✈❛❧❡♥t✱ ♠♦r❡ ❛❧❣❡❜r❛✐❝✱ ❞❡✜♥✐t✐♦♥ ✐s t❤❛t ❚ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ❚ + K (❊) ❜❡❧♦♥❣s t♦ t❤❡ ❏❛❝♦❜s♦♥ r❛❞✐❝❛❧ ♦❢ t❤❡ ❈❛❧❦✐♥ ❛❧❣❡❜r❛ B(❊)/K (❊)✳ ❊①❛♠♣❧❡✳ ❆ ❍✐❧❜❡rt✲s♣❛❝❡ ♦♣❡r❛t♦r ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐t ✐s ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ ✐s ✜①❡❞❀ ♦r ✭✐✐✮ ❝♦♥t❛✐♥s ❊ ✳
✽
❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠
❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❚ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ■ − ❙❚ ✐s ❛ ❋r❡❞❤♦❧♠ ♦♣❡r❛t♦r✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❞✐♠ ❦❡r(■ − ❙❚) < ∞ ❛♥❞ ❞✐♠ ❊ (■ − ❙❚)(❊) < ∞, ❢♦r ❡❛❝❤ ❙ ∈ B(❊)✳ ❚❤❡ s❡t E (❊) ♦❢ ✐♥❡ss❡♥t✐❛❧ ♦♣❡r❛t♦rs ♦♥ ❊ ✐s ❛ ❝❧♦s❡❞✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ❛♥❞ ♣r♦♣❡r ✇❤❡♥❡✈❡r ❊ ✐s ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❆♥ ❡q✉✐✈❛❧❡♥t✱ ♠♦r❡ ❛❧❣❡❜r❛✐❝✱ ❞❡✜♥✐t✐♦♥ ✐s t❤❛t ❚ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ❚ + K (❊) ❜❡❧♦♥❣s t♦ t❤❡ ❏❛❝♦❜s♦♥ r❛❞✐❝❛❧ ♦❢ t❤❡ ❈❛❧❦✐♥ ❛❧❣❡❜r❛ B(❊)/K (❊)✳ ❊①❛♠♣❧❡✳ ❆ ❍✐❧❜❡rt✲s♣❛❝❡ ♦♣❡r❛t♦r ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐t ✐s ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ ✐s ✜①❡❞❀ ♦r ✭✐✐✮ ❝♦♥t❛✐♥s ❊ ✳
✽
❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠
❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❚ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ■ − ❙❚ ✐s ❛ ❋r❡❞❤♦❧♠ ♦♣❡r❛t♦r✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❞✐♠ ❦❡r(■ − ❙❚) < ∞ ❛♥❞ ❞✐♠ ❊ (■ − ❙❚)(❊) < ∞, ❢♦r ❡❛❝❤ ❙ ∈ B(❊)✳ ❚❤❡ s❡t E (❊) ♦❢ ✐♥❡ss❡♥t✐❛❧ ♦♣❡r❛t♦rs ♦♥ ❊ ✐s ❛ ❝❧♦s❡❞✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ❛♥❞ ♣r♦♣❡r ✇❤❡♥❡✈❡r ❊ ✐s ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❆♥ ❡q✉✐✈❛❧❡♥t✱ ♠♦r❡ ❛❧❣❡❜r❛✐❝✱ ❞❡✜♥✐t✐♦♥ ✐s t❤❛t ❚ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ❚ + K (❊) ❜❡❧♦♥❣s t♦ t❤❡ ❏❛❝♦❜s♦♥ r❛❞✐❝❛❧ ♦❢ t❤❡ ❈❛❧❦✐♥ ❛❧❣❡❜r❛ B(❊)/K (❊)✳ ❊①❛♠♣❧❡✳ ❆ ❍✐❧❜❡rt✲s♣❛❝❡ ♦♣❡r❛t♦r ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐t ✐s ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ ❝♦♥t❛✐♥s ❊ ✳
✽
❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠
❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❚ ♦♥ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❊ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ■ − ❙❚ ✐s ❛ ❋r❡❞❤♦❧♠ ♦♣❡r❛t♦r✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❞✐♠ ❦❡r(■ − ❙❚) < ∞ ❛♥❞ ❞✐♠ ❊ (■ − ❙❚)(❊) < ∞, ❢♦r ❡❛❝❤ ❙ ∈ B(❊)✳ ❚❤❡ s❡t E (❊) ♦❢ ✐♥❡ss❡♥t✐❛❧ ♦♣❡r❛t♦rs ♦♥ ❊ ✐s ❛ ❝❧♦s❡❞✱ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ❛♥❞ ♣r♦♣❡r ✇❤❡♥❡✈❡r ❊ ✐s ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧✳ ❆♥ ❡q✉✐✈❛❧❡♥t✱ ♠♦r❡ ❛❧❣❡❜r❛✐❝✱ ❞❡✜♥✐t✐♦♥ ✐s t❤❛t ❚ ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ❚ + K (❊) ❜❡❧♦♥❣s t♦ t❤❡ ❏❛❝♦❜s♦♥ r❛❞✐❝❛❧ ♦❢ t❤❡ ❈❛❧❦✐♥ ❛❧❣❡❜r❛ B(❊)/K (❊)✳ ❊①❛♠♣❧❡✳ ❆ ❍✐❧❜❡rt✲s♣❛❝❡ ♦♣❡r❛t♦r ✐s ✐♥❡ss❡♥t✐❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐t ✐s ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ L ❝♦♥t❛✐♥s E (❊)✳
✽
❚❤❡ ❡q✉✐✈❛❧❡♥❝❡ ♦❢ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■
❘❡❝❛❧❧✿ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ L ❝♦♥t❛✐♥s E (❊)✳ ❘❡♠❛r❦s✳ ❚❤✐s r❡s✉❧t ✐s ❡ss❡♥t✐❛❧❧② ❦♥♦✇♥ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s✱ ❜✉t t❤❡ ❛♣♣r♦❛❝❤ ✐s ✈❡r② ❞✐✛❡r❡♥t ❢r♦♠ ♦✉rs✳ ■t ❝❛♥ ❜❡ ✈✐❡✇❡❞ ❛s t❤❡ ❛♥❛❧♦❣✉❡ ♦❢ t❤❡ ❢❛❝t t❤❛t ❛♥ ✉❧tr❛✜❧t❡r ♦♥ ❛ s❡t ▼ ✐s ❡✐t❤❡r ✜①❡❞ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ❝♦♥s✐sts ♦❢ ♣r❡❝✐s❡❧② t❤♦s❡ s✉❜s❡ts ♦❢ ▼ ✇❤✐❝❤ ❝♦♥t❛✐♥ ❛ ✜①❡❞ ❡❧❡♠❡♥t ① ▼✮✱ ♦r ✐t ❝♦♥t❛✐♥s t❤❡ ❋ré❝❤❡t ✜❧t❡r ♦❢ ❛❧❧ ❝♦✜♥✐t❡ s✉❜s❡ts ♦❢ ▼✳ ❈♦r♦❧❧❛r②✳ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■ ❛r❡ ❡q✉✐✈❛❧❡♥t✱ ✐♥ t❤❡ ❢♦❧❧♦✇✐♥❣ s❡♥s❡✿ ❊✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ♥♦ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦♥t❛✐♥s ❊ ✳
✾
❚❤❡ ❡q✉✐✈❛❧❡♥❝❡ ♦❢ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■
❘❡❝❛❧❧✿ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ L ❝♦♥t❛✐♥s E (❊)✳ ❘❡♠❛r❦s✳
◮ ❚❤✐s r❡s✉❧t ✐s ❡ss❡♥t✐❛❧❧② ❦♥♦✇♥ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s✱ ❜✉t t❤❡ ❛♣♣r♦❛❝❤ ✐s ✈❡r②
❞✐✛❡r❡♥t ❢r♦♠ ♦✉rs✳ ■t ❝❛♥ ❜❡ ✈✐❡✇❡❞ ❛s t❤❡ ❛♥❛❧♦❣✉❡ ♦❢ t❤❡ ❢❛❝t t❤❛t ❛♥ ✉❧tr❛✜❧t❡r ♦♥ ❛ s❡t ▼ ✐s ❡✐t❤❡r ✜①❡❞ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ❝♦♥s✐sts ♦❢ ♣r❡❝✐s❡❧② t❤♦s❡ s✉❜s❡ts ♦❢ ▼ ✇❤✐❝❤ ❝♦♥t❛✐♥ ❛ ✜①❡❞ ❡❧❡♠❡♥t ① ▼✮✱ ♦r ✐t ❝♦♥t❛✐♥s t❤❡ ❋ré❝❤❡t ✜❧t❡r ♦❢ ❛❧❧ ❝♦✜♥✐t❡ s✉❜s❡ts ♦❢ ▼✳ ❈♦r♦❧❧❛r②✳ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■ ❛r❡ ❡q✉✐✈❛❧❡♥t✱ ✐♥ t❤❡ ❢♦❧❧♦✇✐♥❣ s❡♥s❡✿ ❊✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ♥♦ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦♥t❛✐♥s ❊ ✳
✾
❚❤❡ ❡q✉✐✈❛❧❡♥❝❡ ♦❢ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■
❘❡❝❛❧❧✿ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ L ❝♦♥t❛✐♥s E (❊)✳ ❘❡♠❛r❦s✳
◮ ❚❤✐s r❡s✉❧t ✐s ❡ss❡♥t✐❛❧❧② ❦♥♦✇♥ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s✱ ❜✉t t❤❡ ❛♣♣r♦❛❝❤ ✐s ✈❡r②
❞✐✛❡r❡♥t ❢r♦♠ ♦✉rs✳
◮ ■t ❝❛♥ ❜❡ ✈✐❡✇❡❞ ❛s t❤❡ ❛♥❛❧♦❣✉❡ ♦❢ t❤❡ ❢❛❝t t❤❛t ❛♥ ✉❧tr❛✜❧t❡r ♦♥ ❛ s❡t ▼
✐s ❡✐t❤❡r ✜①❡❞ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ❝♦♥s✐sts ♦❢ ♣r❡❝✐s❡❧② t❤♦s❡ s✉❜s❡ts ♦❢ ▼ ✇❤✐❝❤ ❝♦♥t❛✐♥ ❛ ✜①❡❞ ❡❧❡♠❡♥t ① ∈ ▼✮✱ ♦r ✐t ❝♦♥t❛✐♥s t❤❡ ❋ré❝❤❡t ✜❧t❡r ♦❢ ❛❧❧ ❝♦✜♥✐t❡ s✉❜s❡ts ♦❢ ▼✳ ❈♦r♦❧❧❛r②✳ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■ ❛r❡ ❡q✉✐✈❛❧❡♥t✱ ✐♥ t❤❡ ❢♦❧❧♦✇✐♥❣ s❡♥s❡✿ ❊✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ♥♦ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦♥t❛✐♥s ❊ ✳
✾
❚❤❡ ❡q✉✐✈❛❧❡♥❝❡ ♦❢ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■
❘❡❝❛❧❧✿ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ L ❝♦♥t❛✐♥s E (❊)✳ ❘❡♠❛r❦s✳
◮ ❚❤✐s r❡s✉❧t ✐s ❡ss❡♥t✐❛❧❧② ❦♥♦✇♥ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s✱ ❜✉t t❤❡ ❛♣♣r♦❛❝❤ ✐s ✈❡r②
❞✐✛❡r❡♥t ❢r♦♠ ♦✉rs✳
◮ ■t ❝❛♥ ❜❡ ✈✐❡✇❡❞ ❛s t❤❡ ❛♥❛❧♦❣✉❡ ♦❢ t❤❡ ❢❛❝t t❤❛t ❛♥ ✉❧tr❛✜❧t❡r ♦♥ ❛ s❡t ▼
✐s ❡✐t❤❡r ✜①❡❞ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ❝♦♥s✐sts ♦❢ ♣r❡❝✐s❡❧② t❤♦s❡ s✉❜s❡ts ♦❢ ▼ ✇❤✐❝❤ ❝♦♥t❛✐♥ ❛ ✜①❡❞ ❡❧❡♠❡♥t ① ∈ ▼✮✱ ♦r ✐t ❝♦♥t❛✐♥s t❤❡ ❋ré❝❤❡t ✜❧t❡r ♦❢ ❛❧❧ ❝♦✜♥✐t❡ s✉❜s❡ts ♦❢ ▼✳ ❈♦r♦❧❧❛r②✳ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■ ❛r❡ ❡q✉✐✈❛❧❡♥t✱ ✐♥ t❤❡ ❢♦❧❧♦✇✐♥❣ s❡♥s❡✿ ❊✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✐s ✜①❡❞ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ♥♦ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ❝♦♥t❛✐♥s ❊ ✳
✾
❚❤❡ ❡q✉✐✈❛❧❡♥❝❡ ♦❢ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■
❘❡❝❛❧❧✿ ▲❡t ❊ ❜❡ ❛ ♥♦♥✲③❡r♦ ❇❛♥❛❝❤ s♣❛❝❡✳ ❚❤❡♥✱ ❢♦r ❡❛❝❤ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ L ♦❢ B(❊)✱ ❡①❛❝t❧② ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ t✇♦ ❛❧t❡r♥❛t✐✈❡s ❤♦❧❞s✿ ✭✐✮ L ✐s ✜①❡❞❀ ♦r ✭✐✐✮ L ❝♦♥t❛✐♥s E (❊)✳ ❘❡♠❛r❦s✳
◮ ❚❤✐s r❡s✉❧t ✐s ❡ss❡♥t✐❛❧❧② ❦♥♦✇♥ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s✱ ❜✉t t❤❡ ❛♣♣r♦❛❝❤ ✐s ✈❡r②
❞✐✛❡r❡♥t ❢r♦♠ ♦✉rs✳
◮ ■t ❝❛♥ ❜❡ ✈✐❡✇❡❞ ❛s t❤❡ ❛♥❛❧♦❣✉❡ ♦❢ t❤❡ ❢❛❝t t❤❛t ❛♥ ✉❧tr❛✜❧t❡r ♦♥ ❛ s❡t ▼
✐s ❡✐t❤❡r ✜①❡❞ ✭✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ❝♦♥s✐sts ♦❢ ♣r❡❝✐s❡❧② t❤♦s❡ s✉❜s❡ts ♦❢ ▼ ✇❤✐❝❤ ❝♦♥t❛✐♥ ❛ ✜①❡❞ ❡❧❡♠❡♥t ① ∈ ▼✮✱ ♦r ✐t ❝♦♥t❛✐♥s t❤❡ ❋ré❝❤❡t ✜❧t❡r ♦❢ ❛❧❧ ❝♦✜♥✐t❡ s✉❜s❡ts ♦❢ ▼✳ ❈♦r♦❧❧❛r②✳ ◗✉❡st✐♦♥s ■■ ❛♥❞ ■■■ ❛r❡ ❡q✉✐✈❛❧❡♥t✱ ✐♥ t❤❡ ❢♦❧❧♦✇✐♥❣ s❡♥s❡✿ ❊✈❡r② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ♥♦ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ❝♦♥t❛✐♥s F(❊)✳
✾
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿
♣ ❛♥❞ ▲♣ ✵ ✶ ❢♦r ✶
♣ ✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ✮❀ ✭✐✐✐✮ ❊ ❝✵ ✱ ❊ ❍✱ ♦r ❊ ❝✵ ❍✱ ✇❤❡r❡ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿
♣ ❛♥❞ ▲♣ ✵ ✶ ❢♦r ✶
♣ ✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ✮❀ ✭✐✐✐✮ ❊ ❝✵ ✱ ❊ ❍✱ ♦r ❊ ❝✵ ❍✱ ✇❤❡r❡ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ✮❀ ✭✐✐✐✮ ❊ ❝✵ ✱ ❊ ❍✱ ♦r ❊ ❝✵ ❍✱ ✇❤❡r❡ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ✮❀ ✭✐✐✐✮ ❊ ❝✵ ✱ ❊ ❍✱ ♦r ❊ ❝✵ ❍✱ ✇❤❡r❡ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ ❝✵ ✱ ❊ ❍✱ ♦r ❊ ❝✵ ❍✱ ✇❤❡r❡ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ) ✱ ❊ ❍✱ ♦r ❊ ❝✵ ❍ ✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ)✱ ❊ = ❍ ✱ ♦r ❊ ❝✵ ❍ ✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ)✱ ❊ = ❍✱ ♦r ❊ = ❝✵(Γ) ⊕ ❍✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ)✱ ❊ = ❍✱ ♦r ❊ = ❝✵(Γ) ⊕ ❍✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ)✱ ❊ = ❍✱ ♦r ❊ = ❝✵(Γ) ⊕ ❍✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ε > ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ε✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ)✱ ❊ = ❍✱ ♦r ❊ = ❝✵(Γ) ⊕ ❍✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ ❈ ❑ ✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈ ❑ ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ε > ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ε✳
✶✵
P♦s✐t✐✈❡ ❛♥s✇❡rs t♦ ◗✉❡st✐♦♥ ■■
❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ▲❡t ❊ ❜❡ ❛ ❇❛♥❛❝❤ s♣❛❝❡ ✇❤✐❝❤ s❛t✐s✜❡s ♦♥❡ ♦❢ t❤❡ ❢♦❧❧♦✇✐♥❣ ✜✈❡ ❝♦♥❞✐t✐♦♥s✿ ✭✐✮ ❊ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s ❛♥❞ ✐s ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ✐ts ❜✐❞✉❛❧ ✭❡①❛♠♣❧❡s✿ ℓ♣ ❛♥❞ ▲♣[✵, ✶] ❢♦r ✶ ♣ < ∞✮❀ ✭✐✐✮ ❊ ✐s ❛♥ ✐♥❥❡❝t✐✈❡ ❇❛♥❛❝❤ s♣❛❝❡✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❊ ✐s ❛✉t♦♠❛t✐❝❛❧❧② ❝♦♠♣❧❡♠❡♥t❡❞ ✐♥ ❛♥② s✉♣❡rs♣❛❝❡ ✭❡①❛♠♣❧❡s✿ ℓ∞(Γ) ❢♦r s♦♠❡ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t Γ✮❀ ✭✐✐✐✮ ❊ = ❝✵(Γ)✱ ❊ = ❍✱ ♦r ❊ = ❝✵(Γ) ⊕ ❍✱ ✇❤❡r❡ Γ ✐s ❛ ♥♦♥✲❡♠♣t② ✐♥❞❡① s❡t ❛♥❞ ❍ ✐s ❛ ❍✐❧❜❡rt s♣❛❝❡❀ ✭✐✈✮ ❊ ❤❛s ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❊ ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t② ✭❡①❛♠♣❧❡s✿ ❤❡r❡❞✐t❛r✐❧② ✐♥❞❡❝♦♠♣♦s❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡s✮❀ ✭✈✮ ❊ = ❈(❑)✱ ✇❤❡r❡ ❑ ✐s ❛ ❝♦♠♣❛❝t ❍❛✉s❞♦r✛ s♣❛❝❡ ✇✐t❤♦✉t ✐s♦❧❛t❡❞ ♣♦✐♥ts✱ ❛♥❞ ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❈(❑) ✐s ❛ ✇❡❛❦ ♠✉❧t✐♣❧✐❝❛t✐♦♥✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ✐t ✐s ❛ str✐❝t❧② s✐♥❣✉❧❛r ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ ♠✉❧t✐♣❧✐❝❛t✐♦♥ ♦♣❡r❛t♦r✳ ❚❤❡♥ ❡❛❝❤ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊) ✐s ✜①❡❞✳ ❉❡✜♥✐t✐♦♥✳ ❆♥ ♦♣❡r❛t♦r ❙ ♦♥ ❊ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✐❢✱ ❢♦r ❡❛❝❤ ε > ✵✱ ❡❛❝❤ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ♦❢ ❊ ❝♦♥t❛✐♥s ❛ ✉♥✐t ✈❡❝t♦r ① s✉❝❤ t❤❛t ❙① ε✳
✶✵
❚❤❡ ❍✐❧❜❡rt✲s♣❛❝❡ ❝❛s❡
▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❈ ∗✲❛❧❣❡❜r❛✱ ✇✐t❤ ✐♥✈♦❧✉t✐♦♥ ❛ → ❛⋆✳ ❆ st❛t❡ ♦♥ ✐s ❛ ♥♦r♠✲♦♥❡ ❢✉♥❝t✐♦♥❛❧ ♦♥ s✉❝❤ t❤❛t ❛ ❛ ✵ ❛
- ✐✈❡♥ ❛ st❛t❡
♦♥ ✱ t❤❡ s❡t ❛ ❛ ❛ ✵ ✐s ❛ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ ✳ ■t ✐s ♠❛①✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐s ❛ ♣✉r❡ st❛t❡✱ t❤❛t ✐s✱ ❛♥ ❡①tr❡♠❡ ♣♦✐♥t ♦❢ t❤❡ ✇❡❛❦ ✲❝♦♠♣❛❝t✱ ❝♦♥✈❡① s❡t ♦❢ ❛❧❧ st❛t❡s ♦♥ ✳ ❙✉♣♣♦s❡ t❤❛t ❍ ❢♦r s♦♠❡ ❍✐❧❜❡rt s♣❛❝❡ ❍✱ ❛♥❞ ❧❡t ① ❍ ❜❡ ❛ ✉♥✐t ✈❡❝t♦r✳ ❚❤❡♥
① ✐❢ ❛♥❞ ♦♥❧② ✐❢
✐s t❤❡ ✈❡❝t♦r st❛t❡ ✐♥❞✉❝❡❞ ❜② ①✱ t❤❛t ✐s✱ ❚ ❚① ① ❚ ❍ ✇❤❡r❡ ❞❡♥♦t❡s t❤❡ ✐♥♥❡r ♣r♦❞✉❝t ♦♥ ❍✳ ❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s ❢♦❧❧♦✇s ❢r♦♠ t❤❡s❡ ❢❛❝ts ❜❡❝❛✉s❡ ❡❛❝❤ ♣✉r❡ st❛t❡ ♦♥ ❍ ✐s ❡✐t❤❡r ❛ ✈❡❝t♦r st❛t❡✱ ♦r ❍ ❦❡r ✱ ✐♥ ✇❤✐❝❤ ❝❛s❡ ❍ ✳
✶✶
❚❤❡ ❍✐❧❜❡rt✲s♣❛❝❡ ❝❛s❡
▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❈ ∗✲❛❧❣❡❜r❛✱ ✇✐t❤ ✐♥✈♦❧✉t✐♦♥ ❛ → ❛⋆✳ ❆ st❛t❡ ♦♥ A ✐s ❛ ♥♦r♠✲♦♥❡ ❢✉♥❝t✐♦♥❛❧ λ ♦♥ A s✉❝❤ t❤❛t ❛⋆❛, λ ✵ (❛ ∈ A ).
- ✐✈❡♥ ❛ st❛t❡
♦♥ ✱ t❤❡ s❡t ❛ ❛ ❛ ✵ ✐s ❛ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ ✳ ■t ✐s ♠❛①✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐s ❛ ♣✉r❡ st❛t❡✱ t❤❛t ✐s✱ ❛♥ ❡①tr❡♠❡ ♣♦✐♥t ♦❢ t❤❡ ✇❡❛❦ ✲❝♦♠♣❛❝t✱ ❝♦♥✈❡① s❡t ♦❢ ❛❧❧ st❛t❡s ♦♥ ✳ ❙✉♣♣♦s❡ t❤❛t ❍ ❢♦r s♦♠❡ ❍✐❧❜❡rt s♣❛❝❡ ❍✱ ❛♥❞ ❧❡t ① ❍ ❜❡ ❛ ✉♥✐t ✈❡❝t♦r✳ ❚❤❡♥
① ✐❢ ❛♥❞ ♦♥❧② ✐❢
✐s t❤❡ ✈❡❝t♦r st❛t❡ ✐♥❞✉❝❡❞ ❜② ①✱ t❤❛t ✐s✱ ❚ ❚① ① ❚ ❍ ✇❤❡r❡ ❞❡♥♦t❡s t❤❡ ✐♥♥❡r ♣r♦❞✉❝t ♦♥ ❍✳ ❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s ❢♦❧❧♦✇s ❢r♦♠ t❤❡s❡ ❢❛❝ts ❜❡❝❛✉s❡ ❡❛❝❤ ♣✉r❡ st❛t❡ ♦♥ ❍ ✐s ❡✐t❤❡r ❛ ✈❡❝t♦r st❛t❡✱ ♦r ❍ ❦❡r ✱ ✐♥ ✇❤✐❝❤ ❝❛s❡ ❍ ✳
✶✶
❚❤❡ ❍✐❧❜❡rt✲s♣❛❝❡ ❝❛s❡
▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❈ ∗✲❛❧❣❡❜r❛✱ ✇✐t❤ ✐♥✈♦❧✉t✐♦♥ ❛ → ❛⋆✳ ❆ st❛t❡ ♦♥ A ✐s ❛ ♥♦r♠✲♦♥❡ ❢✉♥❝t✐♦♥❛❧ λ ♦♥ A s✉❝❤ t❤❛t ❛⋆❛, λ ✵ (❛ ∈ A ).
- ✐✈❡♥ ❛ st❛t❡ λ ♦♥ A ✱ t❤❡ s❡t
Nλ = {❛ ∈ A : ❛⋆❛, λ = ✵} ✐s ❛ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✳ ■t ✐s ♠❛①✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ ✐s ❛ ♣✉r❡ st❛t❡✱ t❤❛t ✐s✱ ❛♥ ❡①tr❡♠❡ ♣♦✐♥t ♦❢ t❤❡ ✇❡❛❦ ✲❝♦♠♣❛❝t✱ ❝♦♥✈❡① s❡t ♦❢ ❛❧❧ st❛t❡s ♦♥ ✳ ❙✉♣♣♦s❡ t❤❛t ❍ ❢♦r s♦♠❡ ❍✐❧❜❡rt s♣❛❝❡ ❍✱ ❛♥❞ ❧❡t ① ❍ ❜❡ ❛ ✉♥✐t ✈❡❝t♦r✳ ❚❤❡♥
① ✐❢ ❛♥❞ ♦♥❧② ✐❢
✐s t❤❡ ✈❡❝t♦r st❛t❡ ✐♥❞✉❝❡❞ ❜② ①✱ t❤❛t ✐s✱ ❚ ❚① ① ❚ ❍ ✇❤❡r❡ ❞❡♥♦t❡s t❤❡ ✐♥♥❡r ♣r♦❞✉❝t ♦♥ ❍✳ ❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s ❢♦❧❧♦✇s ❢r♦♠ t❤❡s❡ ❢❛❝ts ❜❡❝❛✉s❡ ❡❛❝❤ ♣✉r❡ st❛t❡ ♦♥ ❍ ✐s ❡✐t❤❡r ❛ ✈❡❝t♦r st❛t❡✱ ♦r ❍ ❦❡r ✱ ✐♥ ✇❤✐❝❤ ❝❛s❡ ❍ ✳
✶✶
❚❤❡ ❍✐❧❜❡rt✲s♣❛❝❡ ❝❛s❡
▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❈ ∗✲❛❧❣❡❜r❛✱ ✇✐t❤ ✐♥✈♦❧✉t✐♦♥ ❛ → ❛⋆✳ ❆ st❛t❡ ♦♥ A ✐s ❛ ♥♦r♠✲♦♥❡ ❢✉♥❝t✐♦♥❛❧ λ ♦♥ A s✉❝❤ t❤❛t ❛⋆❛, λ ✵ (❛ ∈ A ).
- ✐✈❡♥ ❛ st❛t❡ λ ♦♥ A ✱ t❤❡ s❡t
Nλ = {❛ ∈ A : ❛⋆❛, λ = ✵} ✐s ❛ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✳ ■t ✐s ♠❛①✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ λ ✐s ❛ ♣✉r❡ st❛t❡✱ t❤❛t ✐s✱ ❛♥ ❡①tr❡♠❡ ♣♦✐♥t ♦❢ t❤❡ ✇❡❛❦∗✲❝♦♠♣❛❝t✱ ❝♦♥✈❡① s❡t ♦❢ ❛❧❧ st❛t❡s ♦♥ A ✳ ❙✉♣♣♦s❡ t❤❛t ❍ ❢♦r s♦♠❡ ❍✐❧❜❡rt s♣❛❝❡ ❍✱ ❛♥❞ ❧❡t ① ❍ ❜❡ ❛ ✉♥✐t ✈❡❝t♦r✳ ❚❤❡♥
① ✐❢ ❛♥❞ ♦♥❧② ✐❢
✐s t❤❡ ✈❡❝t♦r st❛t❡ ✐♥❞✉❝❡❞ ❜② ①✱ t❤❛t ✐s✱ ❚ ❚① ① ❚ ❍ ✇❤❡r❡ ❞❡♥♦t❡s t❤❡ ✐♥♥❡r ♣r♦❞✉❝t ♦♥ ❍✳ ❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s ❢♦❧❧♦✇s ❢r♦♠ t❤❡s❡ ❢❛❝ts ❜❡❝❛✉s❡ ❡❛❝❤ ♣✉r❡ st❛t❡ ♦♥ ❍ ✐s ❡✐t❤❡r ❛ ✈❡❝t♦r st❛t❡✱ ♦r ❍ ❦❡r ✱ ✐♥ ✇❤✐❝❤ ❝❛s❡ ❍ ✳
✶✶
❚❤❡ ❍✐❧❜❡rt✲s♣❛❝❡ ❝❛s❡
▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❈ ∗✲❛❧❣❡❜r❛✱ ✇✐t❤ ✐♥✈♦❧✉t✐♦♥ ❛ → ❛⋆✳ ❆ st❛t❡ ♦♥ A ✐s ❛ ♥♦r♠✲♦♥❡ ❢✉♥❝t✐♦♥❛❧ λ ♦♥ A s✉❝❤ t❤❛t ❛⋆❛, λ ✵ (❛ ∈ A ).
- ✐✈❡♥ ❛ st❛t❡ λ ♦♥ A ✱ t❤❡ s❡t
Nλ = {❛ ∈ A : ❛⋆❛, λ = ✵} ✐s ❛ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✳ ■t ✐s ♠❛①✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ λ ✐s ❛ ♣✉r❡ st❛t❡✱ t❤❛t ✐s✱ ❛♥ ❡①tr❡♠❡ ♣♦✐♥t ♦❢ t❤❡ ✇❡❛❦∗✲❝♦♠♣❛❝t✱ ❝♦♥✈❡① s❡t ♦❢ ❛❧❧ st❛t❡s ♦♥ A ✳ ❙✉♣♣♦s❡ t❤❛t A = B(❍) ❢♦r s♦♠❡ ❍✐❧❜❡rt s♣❛❝❡ ❍✱ ❛♥❞ ❧❡t ① ∈ ❍ ❜❡ ❛ ✉♥✐t ✈❡❝t♦r✳ ❚❤❡♥ Nλ = ML ① ✐❢ ❛♥❞ ♦♥❧② ✐❢ λ ✐s t❤❡ ✈❡❝t♦r st❛t❡ ✐♥❞✉❝❡❞ ❜② ①✱ t❤❛t ✐s✱ ❚, λ = (❚① | ①) (❚ ∈ B(❍)), ✇❤❡r❡ ( · | · ) ❞❡♥♦t❡s t❤❡ ✐♥♥❡r ♣r♦❞✉❝t ♦♥ ❍✳ ❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s ❢♦❧❧♦✇s ❢r♦♠ t❤❡s❡ ❢❛❝ts ❜❡❝❛✉s❡ ❡❛❝❤ ♣✉r❡ st❛t❡ ♦♥ ❍ ✐s ❡✐t❤❡r ❛ ✈❡❝t♦r st❛t❡✱ ♦r ❍ ❦❡r ✱ ✐♥ ✇❤✐❝❤ ❝❛s❡ ❍ ✳
✶✶
❚❤❡ ❍✐❧❜❡rt✲s♣❛❝❡ ❝❛s❡
▲❡t A ❜❡ ❛ ✉♥✐t❛❧ ❈ ∗✲❛❧❣❡❜r❛✱ ✇✐t❤ ✐♥✈♦❧✉t✐♦♥ ❛ → ❛⋆✳ ❆ st❛t❡ ♦♥ A ✐s ❛ ♥♦r♠✲♦♥❡ ❢✉♥❝t✐♦♥❛❧ λ ♦♥ A s✉❝❤ t❤❛t ❛⋆❛, λ ✵ (❛ ∈ A ).
- ✐✈❡♥ ❛ st❛t❡ λ ♦♥ A ✱ t❤❡ s❡t
Nλ = {❛ ∈ A : ❛⋆❛, λ = ✵} ✐s ❛ ❝❧♦s❡❞ ❧❡❢t ✐❞❡❛❧ ♦❢ A ✳ ■t ✐s ♠❛①✐♠❛❧ ✐❢ ❛♥❞ ♦♥❧② ✐❢ λ ✐s ❛ ♣✉r❡ st❛t❡✱ t❤❛t ✐s✱ ❛♥ ❡①tr❡♠❡ ♣♦✐♥t ♦❢ t❤❡ ✇❡❛❦∗✲❝♦♠♣❛❝t✱ ❝♦♥✈❡① s❡t ♦❢ ❛❧❧ st❛t❡s ♦♥ A ✳ ❙✉♣♣♦s❡ t❤❛t A = B(❍) ❢♦r s♦♠❡ ❍✐❧❜❡rt s♣❛❝❡ ❍✱ ❛♥❞ ❧❡t ① ∈ ❍ ❜❡ ❛ ✉♥✐t ✈❡❝t♦r✳ ❚❤❡♥ Nλ = ML ① ✐❢ ❛♥❞ ♦♥❧② ✐❢ λ ✐s t❤❡ ✈❡❝t♦r st❛t❡ ✐♥❞✉❝❡❞ ❜② ①✱ t❤❛t ✐s✱ ❚, λ = (❚① | ①) (❚ ∈ B(❍)), ✇❤❡r❡ ( · | · ) ❞❡♥♦t❡s t❤❡ ✐♥♥❡r ♣r♦❞✉❝t ♦♥ ❍✳ ❚❤❡ ❉✐❝❤♦t♦♠② ❚❤❡♦r❡♠ ❢♦r ❍✐❧❜❡rt s♣❛❝❡s ❢♦❧❧♦✇s ❢r♦♠ t❤❡s❡ ❢❛❝ts ❜❡❝❛✉s❡ ❡❛❝❤ ♣✉r❡ st❛t❡ λ ♦♥ B(❍) ✐s ❡✐t❤❡r ❛ ✈❡❝t♦r st❛t❡✱ ♦r K (❍) ⊆ ❦❡r λ✱ ✐♥ ✇❤✐❝❤ ❝❛s❡ K (❍) ⊆ Nλ✳
✶✶
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ ❆r❣②r♦s✕❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡
❚❤❡♦r❡♠ ✭❆r❣②r♦s✕❍❛②❞♦♥ ✷✵✶✶✮✳ ❚❤❡r❡ ✐s ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ✇❤✐❝❤ ❤❛s t❤❡ ❢♦❧❧♦✇✐♥❣ t❤r❡❡ ♣r♦♣❡rt✐❡s✿ ✭✐✮ ❳❆❍ ❤❛s ✈❡r② ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❳❆❍ ✐s ❛ ❝♦♠♣❛❝t ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t②❀ ✭✐✐✮ ❳❆❍ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❳❆❍ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✷
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ ❆r❣②r♦s✕❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡
❚❤❡♦r❡♠ ✭❆r❣②r♦s✕❍❛②❞♦♥ ✷✵✶✶✮✳ ❚❤❡r❡ ✐s ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ✇❤✐❝❤ ❤❛s t❤❡ ❢♦❧❧♦✇✐♥❣ t❤r❡❡ ♣r♦♣❡rt✐❡s✿ ✭✐✮ ❳❆❍ ❤❛s ✈❡r② ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❳❆❍ ✐s ❛ ❝♦♠♣❛❝t ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t②❀ ✭✐✐✮ ❳❆❍ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❳❆❍ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✷
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ ❆r❣②r♦s✕❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡
❚❤❡♦r❡♠ ✭❆r❣②r♦s✕❍❛②❞♦♥ ✷✵✶✶✮✳ ❚❤❡r❡ ✐s ❛ ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ✇❤✐❝❤ ❤❛s t❤❡ ❢♦❧❧♦✇✐♥❣ t❤r❡❡ ♣r♦♣❡rt✐❡s✿ ✭✐✮ ❳❆❍ ❤❛s ✈❡r② ❢❡✇ ♦♣❡r❛t♦rs✱ ✐♥ t❤❡ s❡♥s❡ t❤❛t ❡❛❝❤ ♦♣❡r❛t♦r ♦♥ ❳❆❍ ✐s ❛ ❝♦♠♣❛❝t ♣❡rt✉r❜❛t✐♦♥ ♦❢ ❛ s❝❛❧❛r ♠✉❧t✐♣❧❡ ♦❢ t❤❡ ✐❞❡♥t✐t②❀ ✭✐✐✮ ❳❆❍ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❳❆❍ ✐s ✐s♦♠♦r♣❤✐❝ t♦ ℓ✶✳
✶✷
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ ✷ ✷ ✲♠❛tr✐❝❡s ❚✶ ✶ ❳❆❍ ❳❆❍ ❚✶ ✷ ❳❆❍ ❚✷ ✶ ❳❆❍ ❚✷ ✷ ❑❡② ♣♦✐♥t✿ ❚✶ ✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t
✶
❚✶ ✶ ❚✶ ✷ ❚✷ ✶ ❚✷ ✷ ❊ ❚✶ ✶ ✐s ❝♦♠♣❛❝t ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ ❊ ✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶ ✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t
✶
❚✶ ✶ ❚✶ ✷ ❚✷ ✶ ❚✷ ✷ ❊ ❚✶ ✶ ✐s ❝♦♠♣❛❝t ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ ❊ ✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶,✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t
✶
❚✶ ✶ ❚✶ ✷ ❚✷ ✶ ❚✷ ✷ ❊ ❚✶ ✶ ✐s ❝♦♠♣❛❝t ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ ❊ ✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶,✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t K✶ = ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✶,✶ ✐s ❝♦♠♣❛❝t
- ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ B(❊)
✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶,✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t K✶ = ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✶,✶ ✐s ❝♦♠♣❛❝t
- ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ B(❊)✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛
♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶,✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t K✶ = ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✶,✶ ✐s ❝♦♠♣❛❝t
- ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ B(❊)✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛
♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞ ✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶,✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t K✶ = ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✶,✶ ✐s ❝♦♠♣❛❝t
- ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ B(❊)✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛
♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r
▲ ✵ ✵ ❱❯ ❲ ✇❤❡r❡ ❳❆❍ ❳❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯
✶
❳❆❍✱ ❱
✶
✷ ✶ ❛♥❞ ❲ ✷ ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❆ ♥❡❣❛t✐✈❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■■✿ t❤❡ ❡①❛♠♣❧❡
▲❡t ❊ = ❳❆❍ ⊕ ℓ∞✳ ❲❡ ✐❞❡♥t✐❢② ♦♣❡r❛t♦rs ❚ ♦♥ ❊ ✇✐t❤ (✷ × ✷)✲♠❛tr✐❝❡s ❚✶,✶ : ❳❆❍ → ❳❆❍ ❚✶,✷ : ℓ∞ → ❳❆❍ ❚✷,✶ : ❳❆❍ → ℓ∞ ❚✷,✷ : ℓ∞ → ℓ∞
- .
❑❡② ♣♦✐♥t✿ ❚✶,✷ ✐s ♥❡❝❡ss❛r✐❧② str✐❝t❧② s✐♥❣✉❧❛r✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ s❡t K✶ = ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✶,✶ ✐s ❝♦♠♣❛❝t
- ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❝♦❞✐♠❡♥s✐♦♥ ♦♥❡ ✐♥ B(❊)✱ ❛♥❞ ❤❡♥❝❡ ❛❧s♦ ❛
♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧✳ ■t ✐s ♥♦t ✜①❡❞✱ ❜✉t ✐t ✐s s✐♥❣❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳ ▼♦r❡ ♣r❡❝✐s❡❧②✱ K✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ ♦♣❡r❛t♦r ▲ =
- ✵
✵ ❱❯∗κ ❲
- ,
✇❤❡r❡ κ: ❳❆❍ → ❳ ∗∗
❆❍ ✐s t❤❡ ❝❛♥♦♥✐❝❛❧ ❡♠❜❡❞❞✐♥❣✱ ✇❤✐❧❡ ❯ : ℓ✶ → ❳ ∗ ❆❍✱
❱ : ℓ∗
✶ = ℓ∞ → ℓ∞(✷N − ✶) ❛♥❞ ❲ : ℓ∞ → ℓ∞(✷N) ❛r❡ ✐s♦♠♦r♣❤✐s♠s✳
✶✸
❍♦✇ ❛❜♦✉t ◗✉❡st✐♦♥ ■❄
❘❡❝❛❧❧✿ ❊ = ❳❆❍ ⊕ ℓ∞✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ ✐❞❡❛❧ K✶ ✐s t❤❡ ✉♥✐q✉❡ ♥♦♥✲✜①❡❞✱ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ ❚✶ ✶ ❚✶ ✷ ❚✷ ✶ ❚✷ ✷ ❊ ❚✷ ✷ ✐s str✐❝t❧② s✐♥❣✉❧❛r ✇❤✐❝❤ ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ ❊ ✱ ✐s ♥♦t ❝♦♥t❛✐♥❡❞ ✐♥ ❛♥② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ ❊ ✳ ■♥ ♣❛rt✐❝✉❧❛r✱ t❤❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■ ✐s ♣♦s✐t✐✈❡ ❢♦r ❊✳
✶✹
❍♦✇ ❛❜♦✉t ◗✉❡st✐♦♥ ■❄
❘❡❝❛❧❧✿ ❊ = ❳❆❍ ⊕ ℓ∞✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ ✐❞❡❛❧ K✶ ✐s t❤❡ ✉♥✐q✉❡ ♥♦♥✲✜①❡❞✱ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✷,✷ ✐s str✐❝t❧② s✐♥❣✉❧❛r
- ,
✇❤✐❝❤ ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ✐s ♥♦t ❝♦♥t❛✐♥❡❞ ✐♥ ❛♥② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ■♥ ♣❛rt✐❝✉❧❛r✱ t❤❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■ ✐s ♣♦s✐t✐✈❡ ❢♦r ❊✳
✶✹
❍♦✇ ❛❜♦✉t ◗✉❡st✐♦♥ ■❄
❘❡❝❛❧❧✿ ❊ = ❳❆❍ ⊕ ℓ∞✳ ❚❤❡♦r❡♠ ✭❉❑❑❑▲✮✳ ❚❤❡ ✐❞❡❛❧ K✶ ✐s t❤❡ ✉♥✐q✉❡ ♥♦♥✲✜①❡❞✱ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ❍❡♥❝❡ ❚✶,✶ ❚✶,✷ ❚✷,✶ ❚✷,✷
- ∈ B(❊) : ❚✷,✷ ✐s str✐❝t❧② s✐♥❣✉❧❛r
- ,
✇❤✐❝❤ ✐s ❛ ♠❛①✐♠❛❧ t✇♦✲s✐❞❡❞ ✐❞❡❛❧ ♦❢ B(❊)✱ ✐s ♥♦t ❝♦♥t❛✐♥❡❞ ✐♥ ❛♥② ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧ ♦❢ B(❊)✳ ■♥ ♣❛rt✐❝✉❧❛r✱ t❤❡ ❛♥s✇❡r t♦ ◗✉❡st✐♦♥ ■ ✐s ♣♦s✐t✐✈❡ ❢♦r ❊✳
✶✹
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡
◗✉❡st✐♦♥✿ ■s t❤❡r❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ s✉❝❤ t❤❛t B(❊) ❝♦♥t❛✐♥s ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧❄ ✭❘❡❝❛❧❧✿ ✐♥ t❤❡ ❡①❛♠♣❧❡✱ ❛❜♦✈❡✱ ❊ ❳❆❍ ✳✮ ❆♥s✇❡r✿ ②❡s✦ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ❆r❣②r♦s ❛♥❞ ❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ❝♦♥t❛✐♥s ❛ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ❨ ♦❢ ✐♥✜♥✐t❡ ❝♦❞✐♠❡♥s✐♦♥ s✉❝❤ t❤❛t✿ ✭✐✮ ❡❛❝❤ ♦♣❡r❛t♦r ❢r♦♠ ❨ ✐♥t♦ ❳❆❍ ❤❛s t❤❡ ❢♦r♠ ❏ ❑ ❢♦r s♦♠❡ ❛♥❞ s♦♠❡ ❝♦♠♣❛❝t ♦♣❡r❛t♦r ❑✱ ✇❤❡r❡ ❏ ❨ ❳❆❍ ❞❡♥♦t❡s t❤❡ ✐♥❝❧✉s✐♦♥❀ ✭✐✐✮ ❨ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❨ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✺
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡
◗✉❡st✐♦♥✿ ■s t❤❡r❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ s✉❝❤ t❤❛t B(❊) ❝♦♥t❛✐♥s ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧❄ ✭❘❡❝❛❧❧✿ ✐♥ t❤❡ ❡①❛♠♣❧❡✱ ❛❜♦✈❡✱ ❊ = ❳❆❍ ⊕ ℓ∞✳✮ ❆♥s✇❡r✿ ②❡s✦ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ❆r❣②r♦s ❛♥❞ ❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ❝♦♥t❛✐♥s ❛ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ❨ ♦❢ ✐♥✜♥✐t❡ ❝♦❞✐♠❡♥s✐♦♥ s✉❝❤ t❤❛t✿ ✭✐✮ ❡❛❝❤ ♦♣❡r❛t♦r ❢r♦♠ ❨ ✐♥t♦ ❳❆❍ ❤❛s t❤❡ ❢♦r♠ ❏ ❑ ❢♦r s♦♠❡ ❛♥❞ s♦♠❡ ❝♦♠♣❛❝t ♦♣❡r❛t♦r ❑✱ ✇❤❡r❡ ❏ ❨ ❳❆❍ ❞❡♥♦t❡s t❤❡ ✐♥❝❧✉s✐♦♥❀ ✭✐✐✮ ❨ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❨ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✺
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡
◗✉❡st✐♦♥✿ ■s t❤❡r❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ s✉❝❤ t❤❛t B(❊) ❝♦♥t❛✐♥s ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧❄ ✭❘❡❝❛❧❧✿ ✐♥ t❤❡ ❡①❛♠♣❧❡✱ ❛❜♦✈❡✱ ❊ = ❳❆❍ ⊕ ℓ∞✳✮ ❆♥s✇❡r✿ ②❡s✦ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ❆r❣②r♦s ❛♥❞ ❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ❝♦♥t❛✐♥s ❛ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ❨ ♦❢ ✐♥✜♥✐t❡ ❝♦❞✐♠❡♥s✐♦♥ s✉❝❤ t❤❛t✿ ✭✐✮ ❡❛❝❤ ♦♣❡r❛t♦r ❢r♦♠ ❨ ✐♥t♦ ❳❆❍ ❤❛s t❤❡ ❢♦r♠ ❏ ❑ ❢♦r s♦♠❡ ❛♥❞ s♦♠❡ ❝♦♠♣❛❝t ♦♣❡r❛t♦r ❑✱ ✇❤❡r❡ ❏ ❨ ❳❆❍ ❞❡♥♦t❡s t❤❡ ✐♥❝❧✉s✐♦♥❀ ✭✐✐✮ ❨ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❨ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✺
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡
◗✉❡st✐♦♥✿ ■s t❤❡r❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ s✉❝❤ t❤❛t B(❊) ❝♦♥t❛✐♥s ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧❄ ✭❘❡❝❛❧❧✿ ✐♥ t❤❡ ❡①❛♠♣❧❡✱ ❛❜♦✈❡✱ ❊ = ❳❆❍ ⊕ ℓ∞✳✮ ❆♥s✇❡r✿ ②❡s✦ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ❆r❣②r♦s ❛♥❞ ❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ❝♦♥t❛✐♥s ❛ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ❨ ♦❢ ✐♥✜♥✐t❡ ❝♦❞✐♠❡♥s✐♦♥ s✉❝❤ t❤❛t✿ ✭✐✮ ❡❛❝❤ ♦♣❡r❛t♦r ❢r♦♠ ❨ ✐♥t♦ ❳❆❍ ❤❛s t❤❡ ❢♦r♠ α❏ + ❑ ❢♦r s♦♠❡ α ∈ C ❛♥❞ s♦♠❡ ❝♦♠♣❛❝t ♦♣❡r❛t♦r ❑✱ ✇❤❡r❡ ❏ : ❨ → ❳❆❍ ❞❡♥♦t❡s t❤❡ ✐♥❝❧✉s✐♦♥❀ ✭✐✐✮ ❨ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❨ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✺
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡
◗✉❡st✐♦♥✿ ■s t❤❡r❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ s✉❝❤ t❤❛t B(❊) ❝♦♥t❛✐♥s ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧❄ ✭❘❡❝❛❧❧✿ ✐♥ t❤❡ ❡①❛♠♣❧❡✱ ❛❜♦✈❡✱ ❊ = ❳❆❍ ⊕ ℓ∞✳✮ ❆♥s✇❡r✿ ②❡s✦ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ❆r❣②r♦s ❛♥❞ ❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ❝♦♥t❛✐♥s ❛ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ❨ ♦❢ ✐♥✜♥✐t❡ ❝♦❞✐♠❡♥s✐♦♥ s✉❝❤ t❤❛t✿ ✭✐✮ ❡❛❝❤ ♦♣❡r❛t♦r ❢r♦♠ ❨ ✐♥t♦ ❳❆❍ ❤❛s t❤❡ ❢♦r♠ α❏ + ❑ ❢♦r s♦♠❡ α ∈ C ❛♥❞ s♦♠❡ ❝♦♠♣❛❝t ♦♣❡r❛t♦r ❑✱ ✇❤❡r❡ ❏ : ❨ → ❳❆❍ ❞❡♥♦t❡s t❤❡ ✐♥❝❧✉s✐♦♥❀ ✭✐✐✮ ❨ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❨ ✐s ✐s♦♠♦r♣❤✐❝ t♦
✶✳
✶✺
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡
◗✉❡st✐♦♥✿ ■s t❤❡r❡ ❛ s❡♣❛r❛❜❧❡ ❇❛♥❛❝❤ s♣❛❝❡ ❊ s✉❝❤ t❤❛t B(❊) ❝♦♥t❛✐♥s ❛ ✜♥✐t❡❧②✲❣❡♥❡r❛t❡❞✱ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧❄ ✭❘❡❝❛❧❧✿ ✐♥ t❤❡ ❡①❛♠♣❧❡✱ ❛❜♦✈❡✱ ❊ = ❳❆❍ ⊕ ℓ∞✳✮ ❆♥s✇❡r✿ ②❡s✦ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ❆r❣②r♦s ❛♥❞ ❍❛②❞♦♥✬s ❇❛♥❛❝❤ s♣❛❝❡ ❳❆❍ ❝♦♥t❛✐♥s ❛ ❝❧♦s❡❞✱ ✐♥✜♥✐t❡✲❞✐♠❡♥s✐♦♥❛❧ s✉❜s♣❛❝❡ ❨ ♦❢ ✐♥✜♥✐t❡ ❝♦❞✐♠❡♥s✐♦♥ s✉❝❤ t❤❛t✿ ✭✐✮ ❡❛❝❤ ♦♣❡r❛t♦r ❢r♦♠ ❨ ✐♥t♦ ❳❆❍ ❤❛s t❤❡ ❢♦r♠ α❏ + ❑ ❢♦r s♦♠❡ α ∈ C ❛♥❞ s♦♠❡ ❝♦♠♣❛❝t ♦♣❡r❛t♦r ❑✱ ✇❤❡r❡ ❏ : ❨ → ❳❆❍ ❞❡♥♦t❡s t❤❡ ✐♥❝❧✉s✐♦♥❀ ✭✐✐✮ ❨ ❤❛s ❛ ❙❝❤❛✉❞❡r ❜❛s✐s❀ ✭✐✐✐✮ t❤❡ ❞✉❛❧ s♣❛❝❡ ♦❢ ❨ ✐s ✐s♦♠♦r♣❤✐❝ t♦ ℓ✶✳
✶✺
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡ ✭❝♦♥t✐♥✉❡❞✮
▲❡t ❊ = ❳❆❍ ⊕ ❨ ✳ ❚❤❡♥ ❡❛❝❤ ❚ ∈ B(❊) ❤❛s t❤❡ ❢♦r♠ ❚ = α✶,✶■❳❆❍ + ❑✶,✶ α✶,✷❏ + ❑✶,✷ ❑✷,✶ α✷,✷■❨ + ❑✷,✷
- ,
✇❤❡r❡ α✶,✶, α✶,✷, α✷,✷ ∈ C ❛♥❞ t❤❡ ♦♣❡r❛t♦rs ❑✶,✶, ❑✶,✷, ❑✷,✶, ❑✷,✷ ❛r❡ ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ✭✐✮ ❚❤❡r❡ ❛r❡ ❡①❛❝t❧② t✇♦ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ ❊ ✱ ♥❛♠❡❧②
✶
❚ ❊
✷ ✷
✵ ❛♥❞
✷
❚ ❊
✶ ✶
✵ ✭✐✐✮
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ t✇♦ ♦♣❡r❛t♦rs
■❳❆❍ ✵ ✵ ✵ ❛♥❞ ✵ ❏ ✵ ✵ ❜✉t
✶ ✐s ♥♦t ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② ❛ s✐♥❣❧❡ ♦♣❡r❛t♦r ♦♥ ❊
✭✐✐✐✮
✷ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳
✶✻
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡ ✭❝♦♥t✐♥✉❡❞✮
▲❡t ❊ = ❳❆❍ ⊕ ❨ ✳ ❚❤❡♥ ❡❛❝❤ ❚ ∈ B(❊) ❤❛s t❤❡ ❢♦r♠ ❚ = α✶,✶■❳❆❍ + ❑✶,✶ α✶,✷❏ + ❑✶,✷ ❑✷,✶ α✷,✷■❨ + ❑✷,✷
- ,
✇❤❡r❡ α✶,✶, α✶,✷, α✷,✷ ∈ C ❛♥❞ t❤❡ ♦♣❡r❛t♦rs ❑✶,✶, ❑✶,✷, ❑✷,✶, ❑✷,✷ ❛r❡ ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ✭✐✮ ❚❤❡r❡ ❛r❡ ❡①❛❝t❧② t✇♦ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✱ ♥❛♠❡❧② M✶ = {❚ ∈ B(❊) : α✷,✷ = ✵} ❛♥❞ M✷ = {❚ ∈ B(❊) : α✶,✶ = ✵}; ✭✐✐✮
✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ t✇♦ ♦♣❡r❛t♦rs
■❳❆❍ ✵ ✵ ✵ ❛♥❞ ✵ ❏ ✵ ✵ ❜✉t
✶ ✐s ♥♦t ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② ❛ s✐♥❣❧❡ ♦♣❡r❛t♦r ♦♥ ❊
✭✐✐✐✮
✷ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳
✶✻
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡ ✭❝♦♥t✐♥✉❡❞✮
▲❡t ❊ = ❳❆❍ ⊕ ❨ ✳ ❚❤❡♥ ❡❛❝❤ ❚ ∈ B(❊) ❤❛s t❤❡ ❢♦r♠ ❚ = α✶,✶■❳❆❍ + ❑✶,✶ α✶,✷❏ + ❑✶,✷ ❑✷,✶ α✷,✷■❨ + ❑✷,✷
- ,
✇❤❡r❡ α✶,✶, α✶,✷, α✷,✷ ∈ C ❛♥❞ t❤❡ ♦♣❡r❛t♦rs ❑✶,✶, ❑✶,✷, ❑✷,✶, ❑✷,✷ ❛r❡ ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ✭✐✮ ❚❤❡r❡ ❛r❡ ❡①❛❝t❧② t✇♦ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✱ ♥❛♠❡❧② M✶ = {❚ ∈ B(❊) : α✷,✷ = ✵} ❛♥❞ M✷ = {❚ ∈ B(❊) : α✶,✶ = ✵}; ✭✐✐✮ M✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ t✇♦ ♦♣❡r❛t♦rs ■❳❆❍ ✵ ✵ ✵
- ❛♥❞
✵ ❏ ✵ ✵
- ,
❜✉t
✶ ✐s ♥♦t ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② ❛ s✐♥❣❧❡ ♦♣❡r❛t♦r ♦♥ ❊
✭✐✐✐✮
✷ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳
✶✻
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡ ✭❝♦♥t✐♥✉❡❞✮
▲❡t ❊ = ❳❆❍ ⊕ ❨ ✳ ❚❤❡♥ ❡❛❝❤ ❚ ∈ B(❊) ❤❛s t❤❡ ❢♦r♠ ❚ = α✶,✶■❳❆❍ + ❑✶,✶ α✶,✷❏ + ❑✶,✷ ❑✷,✶ α✷,✷■❨ + ❑✷,✷
- ,
✇❤❡r❡ α✶,✶, α✶,✷, α✷,✷ ∈ C ❛♥❞ t❤❡ ♦♣❡r❛t♦rs ❑✶,✶, ❑✶,✷, ❑✷,✶, ❑✷,✷ ❛r❡ ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ✭✐✮ ❚❤❡r❡ ❛r❡ ❡①❛❝t❧② t✇♦ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✱ ♥❛♠❡❧② M✶ = {❚ ∈ B(❊) : α✷,✷ = ✵} ❛♥❞ M✷ = {❚ ∈ B(❊) : α✶,✶ = ✵}; ✭✐✐✮ M✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ t✇♦ ♦♣❡r❛t♦rs ■❳❆❍ ✵ ✵ ✵
- ❛♥❞
✵ ❏ ✵ ✵
- ,
❜✉t M✶ ✐s ♥♦t ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② ❛ s✐♥❣❧❡ ♦♣❡r❛t♦r ♦♥ ❊; ✭✐✐✐✮
✷ ✐s ♥♦t ✜♥✐t❡❧② ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧✳
✶✻
❆ s❡♣❛r❛❜❧❡ ❡①❛♠♣❧❡ ✭❝♦♥t✐♥✉❡❞✮
▲❡t ❊ = ❳❆❍ ⊕ ❨ ✳ ❚❤❡♥ ❡❛❝❤ ❚ ∈ B(❊) ❤❛s t❤❡ ❢♦r♠ ❚ = α✶,✶■❳❆❍ + ❑✶,✶ α✶,✷❏ + ❑✶,✷ ❑✷,✶ α✷,✷■❨ + ❑✷,✷
- ,
✇❤❡r❡ α✶,✶, α✶,✷, α✷,✷ ∈ C ❛♥❞ t❤❡ ♦♣❡r❛t♦rs ❑✶,✶, ❑✶,✷, ❑✷,✶, ❑✷,✷ ❛r❡ ❝♦♠♣❛❝t✳ ❚❤❡♦r❡♠ ✭❑❛♥✐❛✕▲✮✳ ✭✐✮ ❚❤❡r❡ ❛r❡ ❡①❛❝t❧② t✇♦ ♥♦♥✲✜①❡❞✱ ♠❛①✐♠❛❧ ❧❡❢t ✐❞❡❛❧s ♦❢ B(❊)✱ ♥❛♠❡❧② M✶ = {❚ ∈ B(❊) : α✷,✷ = ✵} ❛♥❞ M✷ = {❚ ∈ B(❊) : α✶,✶ = ✵}; ✭✐✐✮ M✶ ✐s ❣❡♥❡r❛t❡❞ ❛s ❛ ❧❡❢t ✐❞❡❛❧ ❜② t❤❡ t✇♦ ♦♣❡r❛t♦rs ■❳❆❍ ✵ ✵ ✵
- ❛♥❞
✵ ❏ ✵ ✵
- ,