This is the Birmingham office where plans for the atom bomb were secretly drawn up – five years before Hiroshima.

And it has barely changed over the years, making it one of the city’s hidden spaces.

It can be found at the University of Birmingham , and was once home to professors Otto Frisch and Rudolf Peierls.

They may not be household names but their place in history is assured.

Because they were the authors of the first technical exposition of the atom bomb, the Frisch–Peierls memorandum.

Completed in March 1940, it providing the world with a document detailing the effects of a ‘super bomb’.

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At the time, of course, the document was top secret.

Now, their work is seen as one of the foundations of deterrence theory

The document suggested the best course of defence against Germany’s plans to build an atom bomb was to build one first.

It is a balance which continued into the dark days of the Cold War, and has existed ever since despite disarmament.

Jack Tasker, of the Colmore Business District, and one of the authors of the Hidden Spaces series, says the office’s past is still tangible.

“We visited the office where the pair had worked,” he said.

“It was fascinating to see the space in so many ways unchanged, its original doors, cupboards, windows and carefully preserved scientific instruments, sitting next to a modern heating system and a PC.

“This jarring effect reminds you that this is a university, not a museum – life moves on and so must we.”

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