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T-Mat — also known as T-Matter (PROSE: Second Session) — was a transmat network that had been established on Earth by the mid 21st century and was run by Travel-Mat. (TV: The Seeds of Death)
The technology was invented by Florian Hart's father. (PROSE: The Wheel of Ice) A few decades after the year 2025, T-Mat fought an "intellectual copyright battle" with iTeleport. (PROSE: Horror of the Space Snakes)
The introduction of the T-Mat system and transmat technology marked the end of the First Great and Bountiful Space Race, according to a guide about the Moon written by the Eleventh Doctor. (PROSE: The Doc's Side of the Moon [+]James Goss, The Brilliant Book 2012 (BBC Books, 2011). Page 47.)
T-Mat saw the abandonment of trains, road and air transport since it was instantaneous - people who continued with such forms of transport were considered eccentric, (PROSE: The Seeds of Death) as T-Mat cubicles were used as a reliable and cost-effective means of mass-transporting goods all over the world. The development of T-Mat ultimately led to the abandonment of manned space programmes, with the only launch vehicles remaining being those required to place satellites in terrestrial orbit. It apparently never occurred to anyone in charge that the transmat link between Earth and the moon might one day catastrophically fail beyond the capacity of the moonbase personnel to repair. The Ice Warriors exploited this weakness when they took over the base as a beach-head for their ill-fated invasion of Earth; a corollary of this compromise of the network was a disastrous collapse of global food distribution. (TV: The Seeds of Death)
By 2096, the global teleportation system was considered a failure. (PROSE: The Indestructible Man) In the aftermath of the invasion and the Thousand Day War, the T-Mat network was replaced by the Interstitial Mass Transit System. (PROSE: Transit)
One account claims some scientists, Froyn and Rhynmal, working for the Space Security Service in the year 4000, were working on a molecular dissemination experiment to increase the distance of travel allowed by the T-Mat system. (PROSE: Mission to the Unknown)
Members of the Scarlet Guard wore small T-Mat units on their belts, which they used to travel around Hyspero. (PROSE: The Scarlet Empress)
Mombassa Station had a T-Mat station. (AUDIO: Race Memory)
Legacy[]
A leaflet advertisement was used as evidence in the Second Doctor's trial. (PROSE: Second Session)