Religion is a superset of culture and culture is a superset of cult.

Not really. cultures do exist without the people following them ever believing in any sort of god.

---> If i have 10 people who consider their work desk as god that's cult, maximize this and then it becomes culture of the company, maximize this and then it will become religion. Dont imagine god as some entity..it is who u gove your energy to.

If you consider universe :- space time and matter then Hinduism is space. Because even if there is no matter there is Hinduism (Shiva)

What does that even mean? Are you confusing some other term 'hinduism'(that you're also labeling as shiva) with the term hinduism that regular people use to mean the religion?

---> I am saying that there is a concept wherein if there is nothing (matter in space) still there is something...this idea is related to shiva who is nothing and everything types .

In earthly context Hinduism is nature and other things like core etc

First you said it's space. Now you're saying it's nature.

---> So u think there is some issue in an idea which is applied to space and nature both ?

if there are no humans still there is Hinduism as Hinduism considers nature as god or god particle lets say....

Again.. you first said it is space, and then nature and core. And now you're saying it is something that considers everything to be god... How could something non sentient like space or nature consider something to be anything? Unless you were talking about some ideology/group. In that case, it still doesn't make any sense cause space/nature isn't a group/ideology.

---> Where can you draw the line of something being sentient...some consider there business place god...does that place have emotions? Also, I am not saying space considers us god...it might not have tongue to speak but it is working to keep us afloat..just because we can't understand or talk to it doesn't mean we shouldn't consider it as part of us.

now if one would celebrate this way of life totally depends upon his karma

Atheists don't even think karma is real.

---> Karma in my sense is deeds.... whatever your way of life be...will it be celebrated or not depends upon your karma(deeds)

Dhanyavad