Yes, reductionism can explain everything in the whole Universe

"There's a statement that one can make that would have been completely non-controversial at the end of the 19th century, but many people both in and out of science would argue against it today. Consider for yourself how you feel about it: "The fundamental laws that govern the smallest constituents of matter and energy, when applied to the Universe over long enough cosmic timescales, can explain everything that will ever emerge.""

"This means that the formation of literally everything in our Universe, from atomic nuclei to atoms to simple molecules to complex molecules to life to intelligence to consciousness and beyond, can all be understood as something that emerges directly from the fundamental laws underpinning reality, with no additional laws, forces, or interactions required. This simple idea - that all phenomena in the Universe are fundamentally physical phenomena - is known as reductionism."

"The alternative proposition is emergence, which states that qualitatively novel properties are found in more complex systems that can never, even in principle, be derived or computed from fundamental laws, principles, and entities. While it's true that many phenomena are not obviously emergent from the behavior of their constituent parts, reductionism should be the default position (or null hypothesis) for any interpretation of reality. Anything else should be treated as the equivalent of the God-of-the-gaps argument, and what follows is an explanation as to why."

Reductionism asserts that the fundamental laws governing the smallest constituents of matter and energy, when applied across cosmic timescales, can explain all emergent phenomena. Material structures from atomic nuclei through complex molecules, life, intelligence, and consciousness are described as arising directly from these underlying laws without additional forces or rules. Emergence challenges that claim by insisting qualitatively novel properties in complex systems cannot, even in principle, be derived from fundamental laws. Reductionism is presented as the default scientific null hypothesis, with alternatives likened to God-of-the-gaps explanations. Questions of fundamentality start with Standard Model particles and their interactions.

Read at Big Think