Sikhism does not believe in a judgement day. We believe in the might of akal purakh, the creator who created the entire universe in the blink of an eye and can destroy it similarly. All we know is that akal purakh can do it....will, when, whether, what...all these questions we're too small to answer. Only the creator knows it.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=5787Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/showthread.php?t=5787
What Sikhism teaches us is this. We have been blessed with the human form after 84 lakhs
Joons, these joons are not just limited to living beings but rather rocks, water, celestial bodies...everything that is in this universe and beyond. Hence we should value this life and submit to akal purakh. We'll be judged when we leave this human form. If we have lived this life in his hukum or order then we'll be free from this endless cycle of
joons or else its again the same thing and who knows how long it lasts.
Now the question is what is the hukum. I am afraid I am too incompetent to tell this. You can listen to panth rattan giani sant singh maskeen ji in his katha over japji sahib. you'll easily get it on youtube. Please do listen to it, you'll find the way. Hope this answers all your questions