This is what we found on Wikipedia regarding the TesseracT:

Tesseract (often stylised as TesseracT) are a British progressive metal band from Milton Keynes. The band, formed in 2003, consists of Daniel Tompkins (lead vocals), Alec "Acle" Kahney (lead guitar and producer), James Monteith (rhythm guitar), Amos Williams (bass, backing vocals) and Jay Postones (drums, percussion). The band is currently signed to Kscope. They are credited as one of the bands to pioneer the djent movement in progressive metal. As of 2023, Tesseract have released five studio albums: One, Altered State, Polaris, Sonder and War of Being, as well as three live albums, Odyssey/Scala, Portals, and Radar O.S.T, and the extended plays Concealing Fate, Perspective, Errai and Regrowth.