A hypothesis requires no evidence.

Correct

It’s then tested through repeatable controlled experiments

repeatable controlled experiments are only one aspect of evidence gathering to falsify a hypothesis. Here are a few other methods:

• Observational Astronomy
• Modeling and Simulations
• Indirect Experiments
• Lab Experiments
• Historical Data Analysis

By combining these methods we can still falsify a hypothesis, thus allowing "science to happen".

The events leading to the Big Bang have no evidence.

Correct! There is no evidence for what lead to the big bang because we can't gather any data before it started. But we have mountains of evidence that all point to a "big bang" happening - down to a fraction of a second shortly after it started! [1] [2] [3] [4] [5] [6] [7] [8] .

If science can hypothesize, why can’t religion?

Science is willing to discard ideas that lack evidence or aren't falsifiable. Is religion ready to stop preaching because faith, by definition, is a lack of evidence?

Have you read string theory? It’s no different than Spinoza’s god.

The difference between string theory and Spinoza's god is the falsifiable part. String Theory, being a scientific theory, makes predictions that should be able to be tested through experiments (although testing will likely be a challenge much like Astrophysics and will instead depend on other scientific methods to gather evidence for/against it). Spinoza's God is a philosophical concept and not directly falsifiable through scientific methods. Spinoza's god is the equivalent of me claiming I'm friends with a telepathic unicorn from another dimension, both useless and irrelevant.

[1] Gravitational Waves: https://www.smithsonianmag.com/science-nature/new-cosmic-discovery-could-be-closest-weve-come-beginning-time-180950109/

[2] Redshift: https://socratic.org/questions/how-does-a-redshift-give-evidence-to-the-big-bang-theory

[3] Cosmic Microwave Background Radiation: https://bigthink.com/starts-with-a-bang/cosmic-microwave-background-proves-big-bang/

[4] Abundance of Light Elements: https://map.gsfc.nasa.gov/universe/bb_tests_ele.html

[5] Expansion: https://map.gsfc.nasa.gov/universe/bb_tests_exp.html](https://www.space.com/52-the-expanding-universe-from-the-big-bang-to-today.html

[6] Olbers' Paradox: https://en.wikipedia.org/wiki/Olbers%27s_paradox

[7] Quasars Existence: https://www.astronomy.com/science/60-years-of-quasars/

[8] WMAP Survey: https://en.wikipedia.org/wiki/Wilkinson_Microwave_Anisotropy_Probe](https://www.britannica.com/topic/Wilkinson-Microwave-Anisotropy-Probe