пишут что иногда в ряд R,C,H,O,... между кватернионами H и октонионами O уместно добавить шестимерную алгебру секстонионов S (определение на картинке; U=R^2).
Например, можно определить проективную плоскость SP^2 — 12-мерное вещественное алгебраическое многообразие. Особые точки образуют RP^5, их дополнение — векторное расслоение ранга 4 над Gr(2,R^6). (а проективная прямая SP^1 — особая квадрика в RP^7)
А ещё так можно построить (не простую) алгебру Ли e_{7.5}, которая сидит между (исключительными простыми) алгебрами Ли e_7 и e_8 https://arxiv.org/abs/math/0402157
пишут что иногда в ряд R,C,H,O,... между кватернионами H и октонионами O уместно добавить шестимерную алгебру секстонионов S (определение на картинке; U=R^2).
Например, можно определить проективную плоскость SP^2 — 12-мерное вещественное алгебраическое многообразие. Особые точки образуют RP^5, их дополнение — векторное расслоение ранга 4 над Gr(2,R^6). (а проективная прямая SP^1 — особая квадрика в RP^7)
А ещё так можно построить (не простую) алгебру Ли e_{7.5}, которая сидит между (исключительными простыми) алгебрами Ли e_7 и e_8 https://arxiv.org/abs/math/0402157
That hurt tech stocks. For the past few weeks, the 10-year yield has traded between 1.72% and 2%, as traders moved into the bond for safety when Russia headlines were ugly—and out of it when headlines improved. Now, the yield is touching its pandemic-era high. If the yield breaks above that level, that could signal that it’s on a sustainable path higher. Higher long-dated bond yields make future profits less valuable—and many tech companies are valued on the basis of profits forecast for many years in the future. "Russians are really disconnected from the reality of what happening to their country," Andrey said. "So Telegram has become essential for understanding what's going on to the Russian-speaking world." If you initiate a Secret Chat, however, then these communications are end-to-end encrypted and are tied to the device you are using. That means it’s less convenient to access them across multiple platforms, but you are at far less risk of snooping. Back in the day, Secret Chats received some praise from the EFF, but the fact that its standard system isn’t as secure earned it some criticism. If you’re looking for something that is considered more reliable by privacy advocates, then Signal is the EFF’s preferred platform, although that too is not without some caveats. The perpetrators use various names to carry out the investment scams. They may also impersonate or clone licensed capital market intermediaries by using the names, logos, credentials, websites and other details of the legitimate entities to promote the illegal schemes. Russians and Ukrainians are both prolific users of Telegram. They rely on the app for channels that act as newsfeeds, group chats (both public and private), and one-to-one communication. Since the Russian invasion of Ukraine, Telegram has remained an important lifeline for both Russians and Ukrainians, as a way of staying aware of the latest news and keeping in touch with loved ones.
from kr