Javascript Infinite Loop with Delta Time

Infinite_loop_with_delta_time.js

var lastUpdate = Date.now();
var lastFixed = Date.now();
var fixedTimer=0.02;

var updateInterval = setInterval(tick, 0);
var fixedInterval = setInterval(fixedTick,fixedTimer);

function tick() {
 var now = Date.now();
 var dt = now - lastUpdate;
 lastUpdate = now; 
 update(dt);
 render(dt);
}

function fixedTick(){
 var now = Date.now();
 var dt = now - lastFixed;
 lastFixed = now; 
 fixedupdate(dt);
}