Whether the simplified shape is a sphere or a torus is determined by the behaviour of one-dimensional curves on its surface.

ECONOMIST: Proof of the truth of the Poincar�� conjecture

In this example, the surface is not simply connected and any smoothed-out object looks like a torus with at least one hole.

ECONOMIST: Proof of the truth of the Poincar�� conjecture

The reaction would also be carried out in a differently shaped apparatus not a torus, but a cylinder with a magnetic field running along its axis.

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Until recently he was Director of the United Kingdom Atomic Energy Authority (UKAEA) Culham, with responsibility for the UK fusion programme and operation of the Joint European Torus (JET).

UNESCO: THEMES

The newly identified torus is not only much broader and further out, it is also tilted at an angle of 27 degrees to the plane on which the more traditional rings sit.

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The Joint European Torus (JET) is located in Britain, which is the largest such facility in the world and may be regarded as a prototype for the International Thermonuclear Experimental Reactor (ITER) based in France.

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