LONDON—The dollar slumped to a six-week low against major peers on Monday, with Treasury yields near their lowest in five weeks, after the U.S. Federal Reserve reiterated its view that any spike in inflation was likely to be temporary. The dollar was also held down by improved risk sentiment amid a rally in global stocks to record highs. Bitcoin stabilized after losses from Sunday, when it plunged as much as 14 percent to $51,541, which a report attributed to news of a power outage in China. The dollar index, which tracks it against six other currencies, fell to 91.079, not far from last week’s low of 91.484, a level not seen since March 18. The greenback’s weakness was pronounced across the board on Monday, with the currency hitting multi-week lows against major peers in the G10 group of currencies: the Japanese yen, the Swiss franc, the Australian dollar and the …