But is there any proof that such dimension exists?

Question: But is there any proof that such dimension exists?
ANSWER: No there is not. But its existence can be inferred. If there is a dimension where time and space do operatic and there is such dimension— the world we experience — then We can infer that there is a dimension where time and space do not operate — Nirvana. Again, even though we cannot prove Nirvana exists, we have the Buddha’s word that it does. He told us:

we will know it when we attain it. Until that time, we can still practice.