This 'no' vote self-imposes the spending cut that Greece hates to see but the 'yes' vote also imposes the spending cut. There is no way to avoid a spending cut for Greece.
Austerity is a strange word, it sounds sterile, it has strange connotations. The correct term is spending cuts.
You cut spending if you cannot afford what you are spending on and when you cannot borrow to spend either and in case of chronic offenders the sooner the creditors realize what they are dealing with the healthier for everybody. It's healthier for the spender, who has to come to terms of the impossible situation he is in and it is healthier for the creditor, who will avoid losing even more money. It is healthier for the overall economy not to have welfare State system in the first place, to have people consume based on what they produce and not based on what can be taken from somebody else without any form of repayment.
Real money does not come into being by magic, it is not printed into existence, it is not magically created on a computer. Real money is the result of productive activity, where the word 'productive' really means that something is being produced that others are voluntarily willing to trade for in a way that is sustainable for both, the producer and the consumer.
The world has been playing with fire for the last 100 years with everybody being on fiat, it's been playing with a gigantic fire since the USD became uncontrollably inflationary due to it not being backed by any production (USA has been running half a Trillion USD trade deficit for over a decade now) nor by any money reserves (USD is not backed by gold, Nixon defaulted on the dollar back in 1971, and that's how these problems of inflationary policies and welfare state accelerated).
USA has its own version of what is Greece experiencing right now, that's what 'debt ceiling' is. Many believe that USA can simply print bonds and sell them and get out of jail free, however this only works as long as somebody buys those bonds and the bond market is the biggest bubble of all. USA will have its own currency crisis and bonds are currency promised into the future, so that will also collapse.
As Germany now refuses to just pour money into this bottomless pit called Greece, people will refuse to just pour money into the bottomless pit called USA and that will be even more interesting to observe.
Everybody who tells you 'austerity does not work' are full of it. Austerity means you are not spending money you didn't earn and especially where it concerns consumption rather than investment, and ALL things that people want government to spend on are consumption and not investment, so the important distinction is this: government must be austere, only government austerity can reallocate the scarce resources to people, who will rebuild the economy.
In the long run Greece is better off because of this spending cut, it will learn to live within its means and maybe to produce more and it will have a healthy economy. But like any alcoholic or drug addict apparently it will have to hit the rock bottom before it will reform.