Attention at all passengers. You can now book your train tickets on Uber and get 10% back in Uber credits to spend on your next train journey.

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The Economist. Hello, I'm Andrew Palmer, the Business Affairs Editor,

and this week on Money Talks, our Asia Economics Editor warns that China may be doomed to a debt crisis.

It's very difficult, very rare for a country to amass that amount of debt and that's short of the time

without encountering a serious problem.

We'll hear from a specialist on Game of Thrones about how the

books author deals with the realities of banking and economics. He really has

thought a lot about how finance underpins the quest for power which is what really lies at the heart of the novels.

First though will the real Satoshi Nakamoto please stand up.

Craig Stephen Wright and Australian computer scientist

said this week that he in fact is the author of the white paper published in 2008

on Bitcoin, a cryptocurrency and the writer of its first software.

Ludwig Siegel A, our technology editor, joins me now to discuss our take on whether or not

Mr Wright's claims stack up.

Ludwig Craig Wright talked to you for an economist piece this week. What did you make of his claims?

So when I met him he walked me through his cryptographic proof, the proof that shows that he has certain type of data that only Satoshi Nakamoto could have.

That's the proof basically.

And it looked very legit. I mean, it looked as if it checked out.

I got a bit suspicious when I then put it to him, why don't you kind of take, I send you a message of an article of mine and you kind of sign this a message with your key and thus prove that you are Satoshi Nakamoto because that's kind of a more independent, a better quality proof.

He said no he wouldn't do that because it was too complicated.

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