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How efficient is the bitcoin market? I am confused after comparing buy prices in exchanges operating in different currencies.
For instance, I see that 1 BTC amounts to 347 USD at the moment at one exchange in the US. In an exchange 'Localbitcoins', the lowest buy price I can find is 437 AUD.
Now, at the current exchange rate, 347 USD ~= 393 AUD. It seems to me even with some exchange fees that might be imposed, one can earn arbitrage profit by simply going long in one market and shorting in another. I am sure this is not the case. Am I missing something?